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.
Showing posts with label Charger. Show all posts
Showing posts with label Charger. Show all posts
2009-09-05
Rack for Control Box and Charger
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.
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.
2009-06-23
BMS Charging System Works!
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.
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.
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.
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.
2009-05-26
Battery Boxes Nearly Finished; PCBs, Components and Charger Arrived
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.
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.
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.
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 :).
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.
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.
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.
2008-10-15
Starting my HR-V to HR-EV conversion blog
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.
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 partsAt 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.
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