2009-01-23

Batteries are home!

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
video

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.

2009-01-06

Motor holder made and installed

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.

2009-01-01

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

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!