3E - Electric HR-V

3E is Street Legal!

2010-10-19T23:21:00.006+03:00

I am happy to announce that my 3E, electric Honda HR-V is street legal!
It is the first converted street legal electric vehicle in Lithuania. And I'm proud of it.
The process was challenging and quite work consuming but I was working with good willing people from different institutions and we together were turning problems into solutions. Big thanks to them.
One of the results is 118 pages long technical documentation of converted vehicle containing lots of photos, diagrams and tables with the emphasis on compliance to EU standards for electric vehicles. I believe this work will help other EV builders in Lithuania to make the process much simpler.

Now I'm preparing for CO2 Green Drive initiative show which will happen in Vilnius on October 23rd. My 3E will be among other participants which can be seen here http://www.vilniusco2.lt/en/cars/

I'll put more info about CO2 Green Drive and details of recent work that was done on the car to make it finally street legal EV.

Video of driving 3E - Electric Honda HR-V

2010-08-27T12:07:00.010+03:00

I have recently posted a video of driving my EV on YouTube. Put some music on it from local electronic music band "Mind Engineers" . Enjoy.

I am still working to make the car street legal. We had preliminary inspection with transportation experts and agreed on several main points to be done before final certification:
- Emergency disconnect "Red Button"
- Comparing information of cabin air heater element, brake booster and power steering between original components and new replacements
- Protection cover of power cables underneath the car from physical damage (stones, etc.)
- Marking on high voltage cables with with bright colour (orange or similar)
- Informing driver by sound if he's leaving a drive-active car
- Safety procedures modification for starting and running the car in accordance to EN-1987 standards
- Check the charging connector for compliance to EN IEC-62196
- Preparation of technical documentation of the modification
- Some other smaller ones

As I am the first one to go through such certification in my country it is a bit of learning curve for all of us. But I work with people who have good willing approach and we are gradually solving the problems in our way.
So I am quite busy to finalise these things and finaly get my car certified. I will update the blog with new posts of modifications as I go.

Electromagnetic disturbances tests passed!

2010-07-02T12:23:00.030+03:00

I have been working on paperwork to get my EV street legal recently. One of important tests required by state transport inspection is to pass required electromagnetic disturbances test in accordance to European Economic Comission (EEC) Regulation 10. Specifically relevant requirements are stated in sections 6.2 and 6.3 of this regulation.
The test was conducted by local state Communications Regulatory Authority. The tests done according to ENECE Addendum 9 to the 1958 Agreement E/ECE/324, E/ECE/TRANS/505: Regulation No. 10 - Revision 3.

Both narrowband and wideband tests Passed!

Now I am working with state transport inspectorate to complete the inspection of vehicle and register it as street legal electric car.

3E - Ecologic, Economic, Electric; electric Honda HR-V in exhibition

2010-05-15T22:10:00.007+03:00

I had 2 busy weeks lately: first - preparation for showing the car on exhibition BaltTechnika 2010, second - participation in exhibition itself. My friend Marius, professional designer, has prepared the design for the car and materials for exhibition. During that the new name for this car has developed - 3E - Ecologic, Economic, Electric which has become a logo of this car. So my working project name "HR-EV" is now 3E.
New web site has started http://www.emobilis.lt/ for the car and activity which is just basic info about the car and the controller for it which is named EVMS - Electric Vehicle Management System. This is the name for the development the management system which previously called BCMS (until I included the motor controller in it as well). Info in lithuanian was put first.
The exhibition was quite successful with a lot of attention from visitors and media. This might inspire further development of the product or some more EV conversions in our country.
Here are some photos from Exhibition.

Some more photos of the car outside:

The photos of components arrangement inside:

And here are some pictures of EVMS (Controller, BMS, safety systems in one) touchscreen display which is implemented on Windows mobile device Ipaq hx4700.
The display graphical user interface software is flexible so it can be arranged in many different pages with different indicators on each page showing the parameters sent from main controller module. The layout, indicators, colours, graphics can be adjusted to liking and match the interior of the car.
Here is the Main page showing battery voltage, current, power, energy, momentary and average consumption, distance traveled today and estimated distance left.

Here is the battery cells status screen showing voltage, temperature and balancing voltage of each cell plus average and total voltage of all cells.

Here is the consumption screen showing battery charge, estimated distance left, distance, energy consumption of this trip and today plus average and momentary consumption.

Here is the screen voltages. It shows voltage, current and power of main battery, motor and 12V battery plus position of accelerator pedal at the bottom.

This Charging screen shows charging stage. It shows voltage, current and power set for charger and actual. It also shows cells minimum, average and maximum voltages. Two buttons at the bottom allow you to select the charging rate: slow for 220V/10A socket and fast for 220V/16A socket.

Here is Temperatures screen which shows temperatures of controller (IGBTs power stage), motor, battery minimum and maximum, interior and exterior.

And lastly the main menu which allows to select you the information page you want. The time on stock car clock is wrong as I forgot to set it right :). Note the small card at bottom left? That is the SD card which carries the screen configuration and recorded parameters log files. It records the files constantly producing one file per day.

Here is a short movie of display in action:

Electric car is finished, final touches and bureaucracy left

2010-04-30T20:44:00.000+03:00

Well, I can say that my electric car conversion is finished. It is running fine, controller working well, BMS managing the batteries during charge well, display showing main car and batteries parameters on touchscreen, stock RPM, fuel and temperature gauges on stock dashboard show meaningful values, drive-testing does not show any more quirks to be fixed. There are cosmetic touches left to be done here and there. They would be done during the preparation for this car presentation to the public on May 11th. This is the main activity now. Of course there is no limit to perfection but I'll need to stop myself at some point of "good enough". When car is prepared for presentation I'll make a video of it from all possible aspects I will think of. Until then I would ask for your patience and staying tuned.
Oh, yeah, another important thing after presentation is to go through bureaucracy to get finally registered as roadworthy electric car. This part could be interesting. I think it would be still the first one converted in Lithuania regardless of these big delays I had.

Power Steering

2010-03-03T20:29:00.004+02:00

Power steering is also part of this EV conversion project and I was looking for some time through feasible options from direct electric power steering like in Honda S2000 to traditional hydraulic pump driven by some electric motor. I decided to use the electric power steering pump from Peugeot 307 or Citroen C4. These are integrated motor-pump units. In essence you have to connect it to 12V on one end and hydraulic hoses to the other.
I connected this unit to my Honda's stock power steering column using Honda's own old high pressure hoses. Of course the hose mating adapters needed to be manufactured as all the dimensions of Honda and Peugeot don't match. My friend Gytis helped in it.
The electric connectivity is slightly more complicated than just connecting to 12V. This is because the pump is quite intelligent beast made by Siemens. It has two connectors: 2 thick pins connector (ground and 12V battery - no brain needed here), other is 9 pins connector which was a bit more of fun. If you just connect +12V battery on 2 pin connector nothing happens, and pump does not start. It surely waits for some signals on another 9 pin connector.
After looking through all info I could find on Peugeot on Google I found next to nothing of something useful how these pins are used. I only found that one red wire (5) goes to ignition switch, other two blue (1) and beige (6) to main control block under steering wheel, then other red (4) goes to ABS, other beige (9) goes to block BSI which is controlling the engine and the last white is diagnostic. No info about how are these signals are behaving. In essence this power steering pump is able to adjust its power in reaction to what steering wheel and ABS do but no info how.
So I've done some experimenting with the pump I found that to start you need to connect and keep connected +12V to ignition (5) and make a short +12V pulse on pump enable (9). Then the pump just runs at full power continuously. It is ok for me as Honda's stock hydraulic power steering also operates at full power when engine is running.
So to make long story short to use Peugeot 307 power steering pump you need to connect it's fat 2-pin connector's pin 1 to 12V battery +, pin 2 to 12V battery - (chassis) and 9 pin connector's pins 5 and 9 tied together car's to ignition key's wire Ign1 which becomes +12V when key is turned to "On" position. This way the pump runs when you need it.
Below are some bad quality mobile photos of the pump itself and manufacturing of it's top mounting bar and lower holding arm.

After putting everything together I got nice and smooth power steering feel of the steering wheel.
Mission accomplished.

Mounting battery boxes

2010-02-27T19:37:00.002+02:00

It has been a long pause again in my blog - again. The main reason is that blog update stands not on the top of my priorities list among family, main job, and actually working on HR-EV. I reckon if I would have worked normal working hours it would have taken me around 4 months. But now we are approaching 2nd anniversary of the project. Anyway, it's good that it is moving.

This time I want to show the mounting of battery boxes. Apologies for bad quality photos taken from my mobile because camera died when I needed it and I've been to busy to look for another camera.
The battery boxes are mounted on two 20x20x3 stainless steel angles: one in front bottom and one in rear top.

I used most of the car's stock bolt places on the chassis to fasten front rail using just one additional which was welded in. Rear rail was fastened to bottom sheet of the car where the spare tire is placed.
Here is the picture of one box mounted on the rails.

As you may possibly see the front rail is basically hanging on 4 20x3mm stainless steel bars bolted on top to chassis and bent around the angle bar at the bottom and welded to it. This construction allows the angle to swing a bit which is good as you don't have to be dead precise when making these rails. Being very precise in garage conditions is quite difficult. Lateral stability of this bar is achieved by the fact that boxes are bolted to it and boxes themselves are fastened at rear. The other stability element is the 0.8mm steel cover which is bolted to car and to small legs which were formed from the 20x3 bars bent around the angle ( you can see these three legs on the photo above).
Here is the picture showing the rear of the box and I hope you can see the angle bar in dark top left corner of the photo.

Here is the view from inside the car's trunk where the spare wheel is placed.

You can see 4 bolts caps in a row. That's how the rear bar is attached. Simple, isn't it? Well there are 2 additional long bolts on both sides securing the very ends of the rear rail angle. These are not visible on this photo.
On the above photo there are 4 cut opening providing access to boxes terminals to interconnect them together. You can see couple of LEDs lit up on the left which were shot when BCMS was scanning the cells.

Below are couple of very crappy photos which taken with the same mobile camera. The sad fact for the hobby project is that it is rarely possible to work in daylight as in winter night is starting early and job is usually done after main work. I will re-take with proper camera and place here. I promise :)
Here is the view from front left with all battery boxes in place. You can see the thick cable running prepared to be connected.

Here is dark view from the back bottom view of the batteries (that's how you define darkness :)

Here is the dark view of the batteries on the front rail when viewed from the car front.

Here should be photo of the boxes with protective steel sheet installed but I was too tired to remember to take a picture with it. Next time, when I bring the car on the lift again.

Kelly KDH14651B post-mortem

2009-10-21T14:44:00.002+03:00

There were quite a few things happening since last time and I was so busy working on them that I could not spare time to update the blog timely. My excuse finishes here :)

OK, the main thing was that my Kelly controller KDH14651B blew up in smoke. The good thing about it that after all reading all comments from around the net I was kind of expecting it. In a way I felt a relief that I don't have a doubt about its reliability.
Actually it happened at the end of September when I was drive-testing my HR-EV. I was driving it around for a day to test the power consumption and battery capacity. After fresh charge it scored 53km and 203Wh/km consumption in Vilnius city-like driving profile (quite a few ups and downs) which was quite good comparing to standard 250Wh/km as a benchmark. The main parameters during this event were following: speed ~70km/h, slight up-slope driving for around 2-4 previous minutes, battery voltage ~124V, battery current ~180A, controller heatsink temperature ~+29C. So it blew up while continuously delivering around 22kW power for last few minutes. Just to note that the highest power possible I recorded with Kelly was 43kW.
Kelly were not willing to provide me some money compensation. Only offer was a notable discount on new controller which would be basically the same one as just blew up. This was not an acceptable option. Here I'll put some photos what I found investigating its failure.

Disclaimer: Of course it is not proper engineering failure analysis so I reserve my right to be wrong at some of my conclusions. I am basing my findings on my own electronics knowledge and experience.

First I took out my control box from the car. Looking closely you may see the Kelly's cover is slightly popped open from inside explosion.

And here is the photo to see it closer. The cover was just glued to aluminum chassis.

When taken the controller out of my control box I could open the cover more widely. A lot of black ash inside.

Some ash left on inside of control box where the controller was sitting:

Of course the controller like many products of China was built in such way that it would not be possible to disassemble normally for repair. That is a reason that I have not heard of any repaired Kelly Controller. You just scrap the old one and pay Kelly for the new one. That did not stop me :). I sawed off the two sides of aluminum chassis to split top and bottom parts apart to have access to the whole board. And below is the photo how it looks with the top off.

Hmmm, first impression is bad. Not just because of black ash all over. The layout of components is really bad if you are dealing with multi-hundred A currents switching. The electrolytic capacitors sit on one side and power connectors on the other with many switching transistors in between. This layout is a recipe for uneven current and voltage spikes, temperature distribution and stress on the components. There are 42 IRFB4227 transistors in this controller connected in a half-bridge configuration: 21 on lower arm and 21 on upper. The basic rule of paralleling is to keep the conditions as equal as possible for every paralleled part. This rule was clearly taken carelessly.
In addition to that there is really "interesting" solution to increase the power of the controller taken closely in the picture below.

As you can see there are two 10x1.5mm copper bars connecting the bigger and longer row of power transistors on the left to smaller row on the right. This gives me a clear hint that originally the controller was designed to handle maximum currents of up to "400A" and needing a more powerful model they added this section to extended the current by ~200A-ish to total "650A". That would be OK if design approach was taken properly and wide connector plates were used to ensure small inductance and, again, even distribution. Having a long bar with 15mm2 cross-section would certainly not help to achieve that. In hundreds Amp currents every 0.1uH counts.

Closer look at possible failure cause indicated that the epicenter of explosion was first transistor which was closest to bar connectors. Based on previous observations this surely looked like a most probable place to fail: closest to the load and furthest to filter circuits.

It was clear that this transistor was producing majority of bang and smoke.

The PCB track beneath it was also severely damaged. I reckon that after it's failure all other transistors failed in avalanche fashion which is quite normal for paralleled designs. Out of 42 I found possibly 3 that were showing good initial parameters.

Another point is that it is very important to place good filter capacitors on power lines of such switching devices which could help to reduce voltage spikes and even the conditions for paralleled designs. For that you would need good film capacitors. I didn't find them. I only found ceramic SMD capacitors stacked in several places. These usually not good enough for high current spikes filtering.

The next thing was looking at the attachments of these transistor for heat transfer. For that I was taking off bus bars from the transistors. The bus bars are 3x16mm giving 48mm2 cross-section. This is usually good enough for transferring currents from A to B of 600A from which could potentially be drawn from battery. But on controller itself this should be by a margin bigger to allow more even conditions distribution (again) due to smaller resistance and inductance. Anyway I found that each 7 H-lower arm transistors were attached on L shape 3mm thick aluminum plate which is in turn bolted to the chassis base through PCB. Notice anything wrong? Yes, the PCB was used as a heatsink transfer element! OK, the PCB has perforation with metallisation to build many heat transfer channels but still it is not sufficient to drain the excessive heat from transistors down to the base plate at good rate. Below is the photo of PCB what I found under plate and bus bar.

This makes the excess temperature be the main contributor to failure. Remember, I was driving for few minutes in slight uphill. This allowed the transistor temperature to rise but transfer to baseplate and heatsink was not sufficient to keep transistor in normal operating temperature range.

Here is how the PCB looks from below.

Taking into account MOSFET's increased heat dissipation at increasing temperatures this heat transfer certainly does not look enough to me.

Here is how the aluminum case base plate from below PCB looks.

After these findings I certainly would not buy another one from Kelly even at half the cost because I know it would blow up again. It might work well in golf-kart or similar but it is not suited for high currents.

After that I left without controller. As there are no acceptable options (reliable, not overpriced, flexible, powerful enough, with easy integration, available within 1-2 week lead time, etc) I decided to build my own which would be based on IGBTs. But that is the topic for different post...

Motor RPM Sensor

2009-09-20T19:57:00.002+03:00

I have built motor RPM sensor from Melexis MLX90217 chip and door magnet. The Melexis chip was ordered from DigiKey a while ago and cylindrical magnet has taken from door magnet and reed switch pair which is used in house alarm systems.
I made an enclosure of the sensor from 30x30x2 square steel tube of approx 60mm length. I welded on the 2 mm sheet cover on one end and two holder arms with holes on other end. Then made a 14mm hole on one side and welded in a piece of steel tube. Then I glued in the magnet with MLX sensor on its end directed to the inside of the box with three short wires running out to the outside. These wires are connected to shielded microphone cable which is running from the sensor to control box. I've painted the sensor with hammered black Hammerite, let it dry for a day and attached to motor on accessory axis side. Here are couple of photos of finished sensor. Sorry - didn't have time to capture whole manufacturing process.

The sensor serves second purpose too - it covers the shaft from dirt and moisture to prevent its corrosion.

Intermediate Shaft Holder

2009-09-16T01:00:00.003+03:00

HR-V's ICE engine had a fastening place where the front left driveshaft's intermediate shaft was attached to with three bolts making sure that intermediate shaft sits firmly in it's place in gearbox and is in steady position at the junction with front left driveshaft.

As the ICE is gone this intermediate shaft did not have its attachments position so it had to be manufactured. I took 2mm steel sheet and welded a sort of box with on side concave following Warp 9's contour and the other side flat with three M10 bolts welded in for intermediate shaft bracket attachment.

On concave side there is one hole. This hole is used to firmly attach the holder to the Warp's 5/8" lift eye-hole with one bolt

I painted the part with hammered-black Hammerite, let it dry for a day and attached to the motor and intermediate shaft.

Now this intermediate shaft is not going anywhere.

Rack for Control Box and Charger

2009-09-05T00:56:00.000+03:00

Behind the scenes I was doing occasional test drives of my HR-EV for last few weeks. I don't have video of myself but I have video of my wife's EV-grin when she was first driving it which I'll edit and post it at some near time.
Testing was involving a lot of wiring and parameter tweaking to make more and more features of BCMS and car working. For temporary drives I placed control box on two wooden blocks across longerons of the car which worked quite ok but I don't have the photo of them - sorry :) Then I got to the point when I needed to have control box and charger fixed under the hood firmly for longer drives.
To fix control box and charger firmly I designed and built the rack from stainless steel square tubes. I didn't prepare any drawings or sketches for it since it seemed to be quite trivial task from design point of view.
The rack is basically two 30x20x2 stainless steel tubes across car's longerons connected with two bars and fastening loops for bolts at the end to fix it to the longerons. I used 3 stock bolt places on the car's body for fastening the rack and I had to weld in the fourth nut place where no other suitable option was possible. I drilled and welded in 8 bolts for places where Control box and charger will be fixed
The rack came out quite nice. Here are some photos of it.

The control box is almost finished. Next I'll need to make a cover for it. As you can see at the bottom on the sides are two bars with bolt holes for fastening control box to the rack.

The end of the box has all the connectors and cables. I can disconnect all the cables and take the box out for maintenance of itself or the motor underneath.

Here is the picture of rack placed with charger on it.

And here is the rack with control box on it. Of course control box and charger will normally sit together.

The whole construction came out sturdy but at the same time easily dismantable if maintenance would be needed. The intervention into chassis structure is minimum.

Building Electric Heater

2009-08-13T21:48:00.137+03:00

Hello folks! It's been a while I didn't post any updates. But that does not mean I wasn't doing anything. There are many things that you need to take care of and building a heater for coming winter is one of them.
The heater cores are taken from cheap household ceramic heater-blower.

I've dismantled two heaters to get two ceramic heater elements as I learned from other EV builders that one element is not enough. Here is the picture of them side by side.

I needed to get the HR-V's stock heater radiator out of the car to measure it's dimensions and to build an adequate substitute. It seemed to be a fairly easy task but I found out that I have to completely dismantle cabin dashboard to access the ventilation box, take it off and get the heating radiator out.
Here is how the car cabin looked when I finally took the ventilation box.

Once I opened the ventilation box I got access to liquid heater radiator.

I placed 2 ceramic heater elements on liquid radiator where the best airflow is expected and marked the dimensions outline of them so I would know their location when building heater elements box.

Next I took 0.8mm stainless steel sheet and built the heater box by marking, cutting, bending and riveting it to resemble the dimensions of stock liquid heater radiator. To hold the elements I used the plastic holders that were originally in electric heater. I sawed them off to take the shape and fit side by side. It fastened them to the box using two bent steel sheet retainers which are riveted to the bottom plane of the box. I connected the heater elements through over-temperature protection switches that were in stock electric heaters. I run a 2.5mm2 wires cable through plastic cable-through holder in the same place where one of water pipes is going out on stock liquid heater. This way the heater cable goes out into the engine bay where the liquid heating pipe used to come in. Here is box view from top.

Must admit that initially box came a bit over-dimensioned because stock radiator had round corners while mine had square ones. So to fit it in I had to grind corners a bit and adjust bends. After that it lost a bit of it's tidy look. Here is the view from bottom.

I then placed the newly made electric heater box into ventilation box. Had to make a bit wider openings in ventilation box plastic where white cable holder goes out.

Then I've assembled back the ventilation box and ran a short test by connecting the fan to 12V battery and heater elements to 220V socket. After few brief moments I had around 50 degree Celsius hot air blowing out - should be ok in a car on a cold day. Of course car's nominal voltage is around 140V so out of two 1500W@220V AC rated each heater elements I should be getting around 1900W. I also placed a small DS18B20 temperatures sensor into the box airflow path to be able to measure the air temperature and regulate the heater element temperature from a control box BCMS.

Then I put assembled ventilation box back into the car and started assembling the cabin dashboard again.

This dashboard disassembling and assembling served another purpose too - wiring the additional cables. Cabling took quite some time to do as I was only taking out unneeded cables that were going to ICE and leaving the useful ones. I also had to wire some additional cables to be able to control RPM, fuel level and temperature gauges of Honda's stock dashboard instruments from BCMS. The whole process took about a week working on evenings after the work.

Real characteristics of Kelly KP Series 0-5V Throttle

2009-07-10T22:49:00.000+03:00

As I made the control box and most of its wiring I started experimenting with it on the the desk with 1kW lights connected as the load instead of the motor. I found that I can control the lights with the throttle quite ok but sometimes they go off and sometimes they don't when I release the throttle. I thought that it might be Kelly controller glitches as I didn't trust it.
But then I looked at the voltage of throttle output signal through oscilloscope. And I didn't like what I saw - at released throttle was sometimes producing rippled voltage of sawtooth shape oscillating between 0.9 and 1.2 V at around 30Hz frequency. Sometimes it was stable at 0.9V. I suspected that 5V supply to the pedal could be noisy causing hall chip to generate this ripple but when analyzed it with oscilloscope I found it pretty normal 5V power supply noise ripple of only around 0.1mV which should not be an issue at all. Anyway I added extra 0.1uF capacitor to measured the 5V supply voltage which didn't change anything - I was still seeing the nasty ripple on released throttle. In addition to that the movement range from low throttle to the moment when the output voltage started rising was quite big - around 6 degrees out of ~35 degree range. I also noticed that full open throttle was giving only around 3.8V. This is certainly not even close to 5V stated by Kelly.
After finding that I contemplated on two options: send the throttle back to Kelly for repair or repair it myself. First option looks logical when you are dealing with respectable company in your country which will provide good customer support to resolve the problem. With Kelly it is different story - I've read many posts about terrible support of Kelly in the forums and it could be likely that I would spend additional money and time for shipments of repair/replacement with likely the same end result - throttle not working in full range. It would also be little use trying to claim the money back as Kelly is in China where business ethics in some companies could be close to jungle and their government does nothing to protect foreign customers. So I decided to look what's inside and correct the throttle box myself.
I opened the box using Dremel-style grinder cutting through black potty on the bottom to get to the bottom cover. Finally I opened the bottom cover. I found crudely hand-made marginal quality mechanics that is typical for Chinese products with magnet rotating against hall sensor. The hall sensor is AH49E which is produced by several manufacturers with similar characteristics. Datasheet could be found on http://www.bcdsemi.com/upload/datasheet/AH49E%20P1.1%2020080619.pdf. Datasheet shows that this device has output operating voltages range from around 0.9V to 4.2V so it can never output the voltages close to 0-5V range. This confirms that trying to send the throttle for repair would be waste of time and money as they would likely be replacing it with another AH49E. Replacement could possibly fix auto-generation sawtooth ripple on the output but not the total range.
I understand that the range of 0.9 to 3.8V could also work by adjusting the throttle lower and upper dead limits but such solution was not appealing to me at all.
So I replaced the AH49E with Melexis MLX90215 programmable hall effect sensor. I calibrated the sensor's gain and offset by programming it's parameters and I got stable voltage in 0.2V-4.8V range for full throttle movement range from moment when throttle switch clicks from idle till the throttle is full open. This is what I would expect from product which states that it's range is 0-5V

Conclusion: Kelly KP Series 0-5V Throttle can only give you voltage ranges from 0.9V to 4.2V in best case if you are lucky getting the one which was somehow adjusted to give these voltages range over full throttle movement. But in reality I would expect the range of usable movement and voltages to be even worse. In addition I am not sure self-generation of ripple would not be seen on other units as well. If I was a manufacturer I would not dare to put such specifications for cheating customers. I wish I read something like that before buying anything from Kelly.

BMS Charging System Works!

2009-06-23T20:57:00.011+03:00

I've been working intensively on my battery modules, BMS and charger to get them working together. So here's the story in sequence.

Fun with SMD microbs

My battery modules are made from small SMD components which I was never working with before. My previous electronics experience was with bigger sized and DIP components. So it was a new learning experience as I had with many other areas on this project - a lot of fun and satisfying moments.
On the first PCB I tried soldering these components with fine tip soldering iron which worked but I wanted to try a different way. Popular way which is also used in industry is placing components on the PCB with SMD soldering paste and treating it with heat at which solder melts. In serial manufacturing the boards are soldered by putting them in special owens.
Alternative for manual soldering is soldering with hot air. I used the hot air way although owen method should work too if had an owen. In the beginning I used some small Portasol gas soldering iron with air blower tip. It worked fine but I was not happy that I cannot control the temperature of the air and I can only have a rough estimate of this temperature. So I bought a hot air soldering station which I know I'll use in future too. Soldering the boards with it was an easy job. The tedious but not difficult part of the process was putting SMD paste and placing the components on the boards before blowing them with hot air. No problem with shaky hands and sight. Surprisingly to myself I found it easiest to do it without any magnifying goggles although I had them. My wife said I could be a surgeon. I guess I could :-)
Anyway I liked the process and I think it would have taken me notably longer with traditional components with all legs bending, sticking, soldering and crimping. It has taken me around 2-3 hours for soldering each board consisting of 10 battery modules. So manufacturing 45 modules was not bad at all.

Here is one batch of 10 manufactured boards

And here is a massive array of 36 as 9 others were already sitting on the cells as I was taking this photo :)

Battery module features

I'd like to list features that my designed battery modules have. It was quite long and iterative design and development process and I am happy I finished it. I like the final result.

Here is the list of battery module version 1 features:
- Balancing type: shunting current controlled by microcontroller
- Microcontroller: ATMEL ATtiny25V
- Operating voltage range: 2...5V
- Shunting resistance: 2.35Ohm 10 Watt
- Shunting current control: Pulse Width Modulation
- Communication protocol: custom serial protocol with LIN style sync frame
- Comm. bit rate: 2400bps (may work up to 9600bps or more)
- Comm. line: 1 wire going from module to module in chain - very easy and tidy installation
- Communication isolation: 1 Optocoupler on first module on the 2-wire input from BMS and 1 on the output to BMS over 2 wires back
- Measured parameters: Cell voltage, Cell temperature and shunting PWM value
- Voltage measurement accuracy: +/- 0.01V
- Temperature measurement accuracy: +/- 5C
- Parameter read commands: Read Voltages from all cells, Read Voltage from specific cell, Read Temperatures from all cells, Read Temperature from specific cell, Read PWM values from all cells, Read PWM value from specific cell
- Parameter write commands: Write balancing voltage to all cells, Write balancing voltage to specific cell, Write temperature calibration to all cells, Write temperature calibration to specific cell, Write max allowed temperature to all cells, Write max allowed temperature to specific cell, Write max allowed PWM to all cells, Write max allowed PWM to specific cell, Write cell IDs to all cells and read back the cell count.
- Automatic cell enumeration and counting via Write cell IDs command from BMS
- Automatic microcontroller sleep on idle (no comm from BMS for some time - like 60 seconds) to save power
- Automatic shunting current control via PWM to keep preset balancing voltage
- In-circuit microcontroller reprogamming capability via 1-wire debugWire interface
- LED indication of communication activity and PWM balancing mode
- Voltage spikes protection of the circuit supply, input and output signals
- Low cost due to carefully selected components and their count on each module

BCMS prototype board upgrade with CAN bus and Real-Time clock

I've added Microchip's MCP2515 CAN controller with Philips PCA82C260 CAN interface to be able to communicate with my new PFC 3kW charger from www.hztiecheng.com. My ATmega640 talks to MCP2515 over SPI interface. After few evenings of programming I made CAN bus work and my BCMS started talking to the charger. I can set charger voltage and current and enable charging. Charger returns me actual voltage and current plus the status with info such as overtemperature or battery fault flags. The charger model I have is named 144V/16A but as I learned it is capable of producing currents up to 20A.
Then I worked on programming the charging algorithm which would be suitable for my battery pack. It was done quite quickly to the point where I needed to have some reliable timekeeping. So I decided to finaly implement the real time clock (RTC) into my BCMS.
The RTC is made on Maxim DS1307 chip which is talking to my main processor over I2C interface. It has a Lithium backup button battery to keep the clock running when all the batteries are disconnected.

Here is the photo of the board with the processor off

And here is with the processor on

BMS charging demo

Finally here is a short movie demonstrating my BMS working with charger to charge and balance the battery pack

At this point I will be starting to put all electronics into control box, test it and then put into the car and connect to the motor. I'll put battery boxes with batteries in the back trunk first to have test drives and tune the system. Later I'll put them under car's belly as intended.

Battery Boxes Nearly Finished; PCBs, Components and Charger Arrived

2009-05-26T22:58:00.009+03:00

I've done several things since last update. None of them are finished yet but the goal is getting closer and closer.
Metal works on battery boxes are finished. Boxes and their metal retainer parts are welded, grinded and sanded to the final look. Here is the photo of them stacked together as they would be placed under the car. Only plastic battery retainers and covers left to do before putting the batteries in.

I received manufactured PCBs of my battery modules. The quality is good and boards look nice.

I placed them on the batteries in one box to see how it would look just for fun.

I also received a package of ordered SMD components for my modules - almost 800 items. It would be interesting experience to manufacture 45 boards :) So far I had time just to solder essential components to start the module working. You can see the LED lit on the center of the board that is controlled by ATtiny25V microcontroller which is placed on the center of other side of PCB. It now just runs basic test controlling the shunting current running through two big white 5W resistors. It controls the current using PWM signal switching the big black MOSFET. With 4V voltage shunting current can reach up to 1,7A and resistors get so hot that it is just bearable to touch them with the finger. With this voltage they can dissipate up to 7W of power but I think I'll use about half of that and will have longer balancing stage when charging.

I also received the charger from China. I like the quality and the look. I like that it is sealed it does not have any fans - no worries about moisture and dust getting inside. It came with AC socket and European AC cable. It has couple of meters of thick cable that should go to the batteries on the other side. It also came with CAN bus interface adapter - small black box with white label. I asked for this model because my BCMS will be able to control the charging voltage and current through all charging stages and also receive the status from the charger - cool. Of course I'll have to implement the CAN interface electronics and software of my BCMS. But that is worth it as at the end I will have a well-integrated flexible BMS system.

I also started discussion with local transport inspection and transport experts company regarding registration of my EV to make it street legal. They said they don't have any paperwork prepared yet and I would be the first to do it in Lithuania. So I'll have to work with them to prepare the technical requirements for registration and then arrange my EV inspection according to these requirements. It means more paperwork for me and I would need to push the process forward but I will be able to influence the requirements to better suit my own needs and possibly make them good for other EV converters here. So I reckon it's not that bad.
There are many things waiting to be done but step by step I'm slowly doing them to get closer to the goal.

BCMS and Battery Boxes

2009-05-10T23:48:00.004+03:00

I caught some nasty flu on Thursday and needed to sit at home during almost whole weekend. Luckily wife with baby were out during it - visiting parents, so they were safe. Once I was feeling better I resumed some works on electronics and programming. I sent an order for battery module 45 PCBs. I expect to have them on Friday.

I've started programming the PDA graphical user interface. I'll use IPAQ or similar PDA with PocketPC 2003 system which will be mounted in the dashboard and give all information about car, batteries, temperatures, etc. For starters I just made it read the serial output sentences which are generated by BCMS. The protocol is NMEA which is widely used in GPS devices. I've created some custom sentence names which are used in my BCMS. The idea is that I'll have all parameters information along with GPS position of the car which will help car performance analysis after. Below is PDA emulator's program's simple screen which reads the data from serial port and displays in simple text fields. The parameters displayed are actually measured by BCMS.

When I got better on Sunday afternoon I went to garage and made a short session working on battery boxes. I welded the top mounting flange with one hole for initial mounting of the box. I also welded a M8 bolt part at the botom of the box where the batteries are being put. This bolt will be used to secure and press the batteries with V-shaped frame shown below. This will prevent any possible swelling of the cells.

Next will be a lot of grinding of the boxes to remove excess metal from the welds and improve aesthetic view. Nasty part will be cleaning the welds in inner corners of the boxes as it is not yet done properly. Then I will put stainless steel sheet into the boxes walls and they will be almost finished. Almost... There will be plastic retainer bars inside to stop cells from bouncing in the box. And also some plastic or maybe metal sheet cover on top of the boxes with openings at both ends to allow access for boxes interconnections.

Battery boxes and Control box

2009-05-04T23:34:00.007+03:00

Battery boxes

As mentioned earlier I decided to place all the batteries underneath the car where the fuel tank used to be. After making measurements thinking and modeling I chose to make battery boxes to be fitted from underneath the car thus preserving most of the body structure and not weakening it with serious modifications. The reason is that I am thinking ahead about how I would present the car to inspectors who would be checking it to make street legal. Less modifications to the frame - less problems and questions asked.
So, I will make batteries trays/boxes fit and secure from underneath making only few openings from inside to complete the wiring once the boxes are placed in. There will be 5 battery boxes each holding 9 cells. Each box gross weight will be approx 32kg so it will be manageable to lift it to the car from underneath and secure it by hands of two persons. So you will be able put the whole 160kg of batteries box by box.
Here is the sketch of the battery boxes made with Google SketchUp:

Each box is a frame of stainless steel angle 20x20x3 with 0.8mm stainless steel sheet walls protecting the batteries from outside elements like water, sand and stones (remember they will be hanging under car's belly).
The production of boxes has started. I have made the welding jig to make their geometry solid. Without it would be very difficult to weld the steel boxes with decent precision and correct geometry.

Here is one of the boxes fit test with 9 ThunderSky cells. The cells have their contacts covered with tape - you don't want to short circuit expensive cell, don't you?

Control box

Control box is designed to hold all electronic equipment inside and provide a heat sink for controller and down converter. First of all I don't want any sensitive electronics or high voltage circuit hang outside where the could be touched by water, dirt or anyone's non-careful hands. Safety first. For example a session in car wash could lead to serious components damage or even fire in unfortunate circumstances. Therefore I decided to put all such pieces in one safe place - control box.
The control box will hold Kelly controller, controller cooling fans, DC 144V/13.8V down-converter, main contactor, circuit breaker, shunt resistor, throttle hall converter, multiple 12V control relays and fuses and BCMS master board. It will have two thick cables coming in from batteries, two going to the motor and low voltage signal cables going to many places.
The box is made from 10mm aluminium plate which makes base, 3 walls and internal spacer. The plates are bolted together by M5 bolts. The cover will be from 0.8mm stainless steel sheet.
The inside is divided by internal spacer wall into two sections: high voltage/power section and low voltage section. The sketch is shown in picture. There are two big black fans on top which are placed on the opposite side of the wall where the motor controller is placed for maximum heat dissipation effectivenes. The black box on the opposite side of the controller is DC down-converter. Both controller and converter terminals are placed so that they go out to the high voltage connections subsection on the upper right side of the box. This subsection is separated by plastic spacer plate which isolates the connections subsection to prevent any water or dirt entering there. Contactor, shunt and fuse are shown in this subsection. The subsection below contains BCMS board on the left and throttle pot on the right. Throttle handle is attached on the outside of the box. There will be gas cable connected to it.
The box will be put in the car above the motor in approximate location shown in sketch below. I hope you have enough imagination to see the yellow front of the car, black tire, red motor below and gray brakes cylinder assembly :).

Production of the box has started. The aluminium plates were cut (believe me it is daunting when you don't have the disk saw powerfull enough). A lot of drilling and threading was made.

Some power wiring was made with thick copper bars covered in yellow heat-shrink tubing. Production of each bar to about 1 hour - it looks small but eats your time very quickly.

A bit closer view. Note the two big holes drilled in the base - that's where the thick cables will go to the motor.

That's it for now. Some progress, not too much as I am really struggling to find time to sneak into garage and do some work on my HR-EV.

Electric vehicle brake arrived!

2009-03-24T20:54:00.004+02:00

It's been a while since my last post about HR-V conversion and have you been questioning why? It is because the "Electric vehicle brake" has arrived on Feb 21st. The brake is 53cm long and 3.56kg heavy :)

That's right- I have a firstborn child, a boy whose name is Herkus!

Here is my son Herkus first days of his life in this world.

Here is Herkus and me. No, I'm not Chinese - it is less sleep that I got during these days.

He is an EV brake but he is not an EV stopper and I believe the day will come when he will be an EV accelerator. I continue working on EV although naturally the speed is less with the brake on :)
I've done good progress on several things, which I will post more pictures and detail in new posts shortly:
- Battery Voltage and Current measurement circuit is made and programmed which is communicating to BCMS master module to report measured voltages and currents. Voltage measurement step is 0.2V up to 204V. Current is measured up to 512A with 0.5A steps.
- Made measurements and brainstorming about battery placement in the car. Decided to put all batteries in 5 trays with 9 cells each where the fuel tank used to be - plenty of space there in HR-V. The trays will be fit from below so car lift would be needed. Made one battery tray frame from stainless steel angles to verify the concept.
- Designed the box where controller, contactor, accessory charger, shunt, accelerator pot and other electronics components will be placed securely and safely without any potential of high and low voltages to be touched by water or uncareful hands. Already built the main parts of the box and ready to place the components in. Now working to finish the controller box and start fitting the components inside.
- As Gytis has moved from his garage I now continue working in my small garage below my apartment block. It is small, much less equiped but is much easier to come down to work in the evenings.

Will put more info and pictures in upcomming posts. Stay tuned!

Batteries are home!

2009-01-23T21:20:00.006+02:00

Long waiting is over - batteries arrived to where they belong :) I've received 45 TS-LFP90AHA batteries for my HR-EV after more than two months waiting. They've been sailing from Shenzhen in China to Hamburg in Germany and then to Klaipeda in Lithuania - a long trip.

I've taken them from warehouse after customs clearance in my trusty Subaru.

Shortly after I've opened the boxes to see what's inside. I found nicely printed manual and quality certificate. Quality certificate has lots of useful information in Chinese :) User nice manual was the same as pdf available from ThunderSky site. Beneath white cover I found a surprise - batteries :).

Here's a video shot from breathtaking moment :-D

The look at the battery itself.

All the batteries read voltage of 3.30V or 3.31V - GOOD!

The road to the future :)

While I was waiting for the batteries I've been working a lot on BCMS prototype electronics and programming. Here's a brief update about the progress:
- RealTime OS launched on ATmega640
- Serial communications programming wired and programmed - talking to PC now
- Connected to battery modules (at bottom) via opto-coupled serial port and launched battery voltages reading for BMS operation. It ballances Lithium Polymer cells within 0.02V of each other.
- Wired and programmed MLX90215 sensor (small board assembled on the left) so I can measure current of up to 10 Amps to test the concept. The finished sensor will be able to measure up to 700A from batteries and to the motor.
- Wired a contactor control circuit (simple IRL3705 MOSFET switch) and programmed its control
- Wired and programmed 12V line voltage measurement using mega's ADC
- Wired and programmed DS18B20 sensors for BCMS, Controller, Motor, Outside, Inside and Batteries temperature sensing.
- Started wiring a slot for SD/MMC card where the HR-EV's parameters log would be stored
- Some small stuff...

There are many things left to do on electronics until I start the first test of the car:
- Finalize battery module schematics, programming and PCB design, try final prototype on real battery and then order parts and PCBs
- Make schematics/wiring and programming of opto-isolated battery voltage measurement
- Make motor RPM sensor using MLX90217, wire it and program RPM calculation
- Wire gearbox speed sensor and program the speed calculation
- Make throttle sensing and control schematic and programming
- Wire digital inputs like key switch, charger on, throttle idle, gearbox neutral etc.
- Program the safety and control. Basically it should shut off main contactor if any important parameter goes critically off.

Well, there is much much more. One thing - I still haven't got the charger. In the beginning I thought about Zivan NG3 but now I'm not so sure. Still have to decide... and order it.

Of course there are lots of mechanics works to do as well. I'll update as I progress.

Motor holder made and installed

2009-01-06T22:31:00.005+02:00

Last couple days I've spent manufacturing the motor holder from accessory end to remove any temporary hanging arrangements. The part is quite simple but to make it right took some time. As I am using native rubber pads to attach the gearbox and motor to the car body frame. I've seen some builders attach the motor with hard parts but I don't like such approach. Even if there is virtually no vibration from electric motor the rubber pads help to remove the stress from holding parts and dampen torque shocks which should give even smoother operation.
This decision complicated the task of deciding on holder's measurements. The rubber parts stretch and you cannot be sure what measurement of the holder would be the best. Even if this is not critical I want to build things as right as possible from engineering point of view for this conversion without cheap shortcuts.
I decided that I would trust Honda engineers to determine electric motor fitting position. The removed 1.6l Honda IC engine weighted over 90kg. The electric Warp 9 is around 80kg which is quite similar. So I took measurements from ICE native holder part picking crankshaft center at the front as position reference. Then I used Warp9's CE shaft center to calculate the required part dimensions which would hold the electric motor in the same attitude as original petrol one. This measuring and design drawing alone took few hours. After that there were series of operations of metal measuring, cutting, grinding, drilling, sanding, welding, trial-fitting, grinding, sanding, painting and assembling (this is simplified procedure :).

The part turned out ok - approved by sleepy Baja below.

And here ar some photos of it installed - no more temporary attachments. View from car front.

From below

And from top.

Looks alright. We had some debate about thickness of the flat steel plate. But after trying to mentally model the forces applied to this part we came to conclusion that this thickness is definitely enough as the load is distributed through bigger area of it.

That's it for now - motor is installed safely. It gets to -20 Celcius at nights and its no fun working the garage. I'll focus on BCMS electronics now until it gets warmer or I need to remove the dashboard for instruments connection to BCMS.

Motor installed, HR-EV has made her first run!

2009-01-01T20:41:00.011+02:00

The end of 2008 was really busy working on my HR-EV. I've reached one major milestone of the project! But let's go in sequence.
I picked up the shaft coupler disk and spacers from workshop where they've been thermally hardened.
I've marked the spots for two fixing nuts on motor's shaft and drilled two dimples on both sides where the coupler disk's fixing bolts would sit in.
Next we put adapter plate spacer disk on the motor and pressed on the shaft adapter disk onto Warp9's motor shaft. We used 20-ton garage press to press it on. It was going stiffly but smoothly - it wouldn't go anywhere. Below Gytis is happy with the result :)

Here is the closer view

Then I assembled the shaft coupler on it and locked the coupler disk on motor's shaft with two hex fixing bolts. I used thread locking glue to make fixings bear the vibration.

And then I bolted on the gearbox adapter plate using the imperial/metric threaded studs and secured everything with thread locking glue.

A closer view

Then I've put the gearbox on and secured it with the bolts. The shafts and alignment rings fit like a glove without a fight. Phew, what a relief ... :)

Then my photo camera battery died and I used the video camera to shoot the further process. On this occasion I've compiled a small video from latest material together with some old video footage from the progress on HR-EV. If they say a picture is worth a thousand words then video should be worth a million. This is my first published video for this project. Have fun :)

In short later that night I've installed motor and gearbox in Honda and did the trial again using battery charger.
Then next day I took 100Ah 12V lead acid deep cycle battery and put it in HR-EV. I've wired it to motor via contactor relay. The relay is activated with simple pushbutton switch pressed by the driver :) No controller yet. This allowed to make the first ride in HR-EV and it will be used to drive the car into garage on its own power when needed. This is because Gytis' garage has to earn money working on other customers cars while HR-EV is an after-work hobby activity slotting in when car lift is free, etc.
And of course this allowed to have some taste of EV grin :)
This is quite symbolic as it was done on the last day of 2008 and I have had really nice feeling meeting the new year.

Happy New 2009 Year to All!

Motor and gearbox mated, shafts not yet

2008-12-28T10:50:00.008+02:00

I've done some good progress on motor and gearbox works. There was a great deal of help from my friend Gytis who runs the garage I'm working in on my HR-EV!
I've got the manufactured parts from workshop: gearbox adapter plate spacer disk, shaft coupler flange disk, 8 spacer rings for clutch parts assembly and 4 studs for motor which have 3/8 abnormal thread on one end and normal M10 on the other :) Manufacturing cost me around $250 which was not cheap but much less than original quote I've received. Although I couldn't avoid quirks which I'll have to sort with the workshop guys tomorrow.
The quirk was manufactured shaft coupler disk. It looked alright at first glance.

But when trying to bolt it to clutch parts the holes were not aligning by some 2mm! Initially I thought I've made an error making measurements or the drawing which was given to the workshop. I've measured clutch holes positions again and got 47mm from the center. I took my drawing and it said 47mm too.

The holes on actual part were 45mm from the center. So I'll have to bring it workshop for re-drilling the holes in correct places offsetting them by 45 degrees. I could have done this myself but I paid healthy money for it so I should expect the work to be done for it. That is not counting the semi-damaged part. This stopped the works on it for the weekend but we could still progress with gearbox adapter plate.

We finished the thick motor spacer disk holes and studs for them so they fit tight in their places. For now just placed them on copper grease for easier work while working on center alignment. Later we'll put them on bolt glue in the motor so they stay firmly in their places in motor.

Next we drilled the holes in thinner gearbox adapter plate and mated it to gearbox.

After this we attached a circular our own assembled drawing device to gearbox shaft and drew the circle rotating the gearbox shaft by clutch part.

Then according to drawn outer line placed the thick motor spacer disk and aligned to match the center position. Our estimated centering error with this method should be something like 0.1-0.3mm which should be fine for this assembly using clutch spring damper. The thick spacer holes were used as drill guides for drilling the holes in exact locations for thinner one.

After that we put motor vertically and put gearbox on it.

You can see that gearbox shaft goes inside motor's shaft end hole as was designed leaving 2mm space. Shafts centers alignment looks ok. We'll have to check it once we have the shaft adapter disk corrected tomorrow.

And from a bit different angle

Next we'll finish shaft parts and mate the shafts together. Then it should be fairly easy to put the gearbox and motor into the HR-EV. I hope we can do this before the New Year to have a stronger reason to celebrate :)

Adapter and BCMS works ongoing

2008-12-23T11:17:00.004+02:00

The gearbox adapter production is in progress although not as fast as I would have liked. The gearbox plate was cut to gearbox contour with UHP water cutter. Spacer produced on lathe. Adapter disk production is on final. The gearbox was brought to workshop for all parts mating. Sorry - no pictures yet. I hope I'll collect it before Christmas and install motor straight after Christmas.
I was fighting with BCMS Atmega640 over the weekend and could not get it running stable - it was driving me nuts. And yesterday night I just came with fresh view and approached the problem from different angle. I found the root cause which was quite silly that I don't want to talk about. I should get it running OS performing basic comm tasks in few days now. I'd like to get it talking to my battery modules prototypes and to PC. Then I'll focus on building the main contactor control, temperature, voltage and current measurement circuits as these would be required soonest to measure main parameters for safe testing.

Motor adapter and BMS works ongoing

2008-12-18T20:42:00.005+02:00

Last few days been involved in other activities and little time was left for the EV project. Anyway I had time to arrange all activities for gearbox adapter and shaft coupler. I've purchased the materials and brought them to workshops. Realistic timing is to have the parts made for the beginning of next week.
There was some progress on Battery Module PCB design. I've made it to the point where it is nearly finished and I could finalize it and send the design files to PCB manufacturers. But I've decided to wait until my batteries arrive and make a final fit check on actual cell before ordering PCBs production. My batteries are still sailing to me and according to the documents I should expect them around December 26th.
So far my nearly finished design is shown below. Just top copper is shown for clarity.

For now I'll put it asside and will resume work on master module on recently received ATmega640 MCU and various sensors. I've decided that I won't produce any PCB for master until I have fully functioning prototype working in the car. Only then I'll produce the PCB mostly with SMD components for the car computer.
Below is the initial board with MCU on adapter board. It will start growing with various components around it quickly and and I'll adapt the Real-Time Operating Systerm (RTOS) for it as I did for ATmega16.

Motor adapter design homework

2008-12-15T21:38:00.011+02:00

After disappointment with quoted workshop all-inclusive services price I took the adapter production process control to myself. I've disassembled the clutch by taking the outer friction disk off and grinding off the pins holding three metal pieces together. You can see the angle grinder marks around these holes.

These three pieces will be bolted with M8 bolts to the Warp 9 shaft adapter steel disk which will be manufactured in different workshop according to my drawing.

The whole assembly will look like this:

The two simplified clutch parts are yellow with orange spacers keeping them apart. They are bolted by four M8 bolts to the green shaft adapter disk.
The light blue are the motor-gearbox adapter plates. The thinner one is 16mm durable aluminum that bolts to the gearbox following its contour. The thicker one is the 25mm spacer disc to provide required spacing between my HR-V's gearbox shaft (purple) and Warp 9 shaft (red). The thicker one is quite simple round disk part and I've prepared the engineering drawing for its manufacture.
The thinner one must follow the contour of gearbox so I have to prepare a template for it.

Template was taken by putting the A2 size thick white sheet of drawing paper on the gearbox, making the guide holes so it does not move and then hammering on the edges with a rubber mallet so it left clear imprint of edges. As you can see the gearbox is still unwashed and it left clearly visible marks on the paper. I've then drawn the required plate contour along these edges making clear where will I need the cut. I've also marked 18cm opening in the center around shaft position. I've tried to make quite precise but the precise location is not of high importance as it would be corrected after motor and gearbox shafts center alignment. And I've got a bit dirty but clear template for adapter plate.

Next I'll take the required materials from supplier and bring these pieces along with drawings and templates to various workshops for manufacture. The gearbox adapter plate will be likely cut with UHP water jet cutter. Other parts are easily done on lathe bench.
If I'm lucky I might be able to collect all manufactured pieces this week and start motor installation on the weekend.

Shock from workshop!

2008-12-10T20:21:00.003+02:00

Just got the quote from metal workshop about motor-gearbox adapter plate and shaft coupler production. They've quoted the sum equivalent to around $700-800 for materials and works for this not so complicated product! I really hate when someone is trying to rip me off just because they see that the project is not cheap and quality is needed. I'll skip their offer. Anyway I'll have to look for another workshop or other option to produce the adapter plate and coupler.

More progress on battery module

2008-12-09T23:09:00.004+02:00

Battery module design is being finalized with additional details for final production which were not needed in prototypes. Added the parts such as optional pulldown resistors, optional shunt LED, optional optocouplers and connector for master. Few minor changes still remaining but it is almost there and PCB design is half-finished.
If someone's watching this blog I know they'll have questions about two serial connectors and optocouplers. So I'll explain it now.
Two serial connectors are designed in such a way that wiring the the boards should be easy with single short wire going from cell to cell. You'll get the idea when I finish and post PCB design.
Optocouplers are not needed on all cells except the lowest and the highert in the chain. The lowest cell (the one having minus terminal running to the controller) will have the board with U2 optocoupler and J2 connector for serial input. The highest cell (with plus to controller) will have U3 uptocoupler and J2 connector for serial output. This saves the cost by needing just one PCB design and fewer components on it and the area of the PCB as connector J2 is shared.

Sensor chips arrived

2008-12-08T18:09:00.004+02:00

My Melexis MLX 90215, 90217 and Allegro ACS754LCB-100-PFF sensor chips arrived:

They are kind of urging me to finish the work on battery modules and get back to BCMS master module design and prototyping. The functions of these received chips will be following:

MLX 90215 will measure the high currents (up to 650A) from batteries and to the motor.
MLX 90217 will measure the RPM of the motor on teethed gear mounted on the accessory shaft of my Warp 9
ACS754 will measure the charging current, DC/DC converter current and accessory battery draw current

Motor arrived and works started, BMS prototype in progress

2008-12-05T13:52:00.004+02:00

My Warp 9 motor arrived in November - heavy beast. I've taken the ICE out from Honda. The gearbox and Warp9 were taken to metal workshop to produce the adapter plate with perfect center alignment. Adapter plate will be produced from 12mm aluminum sheet with the 30mm spacer for the motor flange. No clutch. Shaft adapter will be done from original clutch disk part bolted on steel disk mounted on Warp9 shaft.

As told earlier I will make my own integrated Battery management and Car management system with instruments. So far made following progress on it:

Battery Module prototype made and programmed.Tests ongoing on model Lithium Polymer batteries. It is nicely balancing the 3-cell pack controlled by PC software via serial link. One module schematic is shown here:It is derived from a nice project being developed by Peter Perkins at http://www.batteryvehiclesociety.org.uk/forums/viewtopic.php?t=1245 .
Once I finish testing I'll design and order PCBs along with all electronic parts needed for them.

Master module prototyping started with real-time OS launched. Comms and several sensors tested. The core system will be based on ATmega 640 microcontroller. Interface will be provided on Pocket PC display running the GUI software which communicates to master module and displays graphical result. The screen will be integrated in the dashboard to blend into interior design.
Ordered more sensors chips to have various measurement inputs.

45 TS 90AH batteries were ordered and sailing to me.

Equipment arrived since last post:
Motor: NetGain Warp 9
BMS: various chips and sensors

Ordered:
Batteries: 45 Thundersky 90Ah LiFePO4s
Vacuum pump: Mes-Dea ( haven't arrive yet)
BCMS: various sensors

Need to decide and order:
Battery charger: haven't decided yet
BCMS: haven't decided which cheap Pocket PC to take as a basis for dashboard screen
Power steering: would like to find an electric steering actuator similar to used in MGs

Work done:
ICE taken out. Warp9 adapter plate started. BMS battery module schematics design and programming almost finished. BCMS design guidelines decided. BCMS master module prototype started. Simple PC software for managing batteries made.

To-Do list: (Long... but main things are generaly listed in no particular order. Later smaller subtasks would be put in detail)

Install the gearbox and motor when adapter plate finished
Make battery boxes once batteries arrive
Design the platform for controller and electronics installation
Decide about charger ( might design my own 2kW charger...)
Finish BMS battery modules design and order PCBs and components, build the modules
Make a BCMS master prototype to perform basic functions to make a first drive-test safe for me and for equipment
Design and laydown all the power and signaling cabling in the car
Make a dashboard design change to integrate the BCMS Pocket PC screen
Develop a software for Pocket PC to indicate main parameters
Build a cabin heater
Build power brakes system
Decide upon and build a power steering system

Starting my HR-V to HR-EV conversion blog

2008-10-15T20:19:00.003+03:00

This is my first entry to log my experiences on conversion of Honda HR-V to electric vehicle. I've decided to do it since my current Subaru is quite old and I want my next car to be electric. There are no affordable electric cars available yet so I've decided to do my own conversion in similar way as many people around the world already done. In the beginning I estimated this conversion to take about 3 months but now I see it would take much longer since I decided to take more expensive components than initially thought and that makes funding the project stretched longer in time.

It is nice golden yellow 3-door 4WD SUV

I like the look from the back too

The hood opened before starting to take all unneeded mechanical parts

At this moment I have following components:
Donor car: Honda HR-V '99 4WD
Controller: Kelly KDH16501
DC-DC converter: Kelly 144V to 13.8V, 25A
Throttle: Kelly hall throttle pedal 0-5V
Contactors: Kelly 400A
Shunt: 500A 50mV
Instrument: Westach ammeter

Ordered:
Motor: NetGain Warp 9
Vacuum pump: Mes-Dea

Need to decide and order:
Batteries: most likely TS LiFePO4
Battery charger: haven't decided
BMS: will make my own...
Car management system / instruments: will make my own integrated to BMS...

Work done:
Not much yet. Bought the donor car, started stripping it down, bought some components. More information on progress should come in next posts as I make bigger steps.