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Discussion Starter · #1 ·
Sorry if this has been discussed before. I have an Alta electric motorcycle. The standard charger is basically an Elcon/TCCH PFC 2500, with Can bus controller, in a different case. Right now to charge, when owners can't connect to the grid, people are using generators or a battery pack with an inverter. In the past I have powered Vicor power supplies with DC. The input basically goes right into the rectifier, so if you hook it up right, DC will just passes through the rectifier and moves on. I was wondering if I could do the same with an Elcon/TCCH charger? It would basically save the step of converting from DC to AC and then back to DC.

Thanks for the help.

Bluefxstc
 

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Sorry if this has been discussed before. I have an Alta electric motorcycle. The standard charger is basically an Elcon/TCCH PFC 2500, with Can bus controller, in a different case. Right now to charge, when owners can't connect to the grid, people are using generators or a battery pack with an inverter. In the past I have powered Vicor power supplies with DC. The input basically goes right into the rectifier, so if you hook it up right, DC will just passes through the rectifier and moves on. I was wondering if I could do the same with an Elcon/TCCH charger? It would basically save the step of converting from DC to AC and then back to DC.

Thanks for the help.

Bluefxstc
I don’t believe it will work but I can take a look at the code later and verify. The software is looking for 120v AC on the input before it will turn on as I remember it. Maybe kennybob or coulomb would know off the top of the head.
 

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Thanks, I appreciate the help
Out of curiosity why would you use DC? AC is everywhere. DC sources are hard to come by..... That being said, the TCCH charger is power factor controlled. It uses an L4981AC Power Factor control chip https://www.google.com/url?sa=t&rct...ctronics.pdf&usg=AOvVaw0fMaGeFFJeMThldGVxvlF1

I am not a real good analog designer so not sure how this chip would work on DC. It doesn't appear the software would stop you its looking at this voltage with an op amp through an optocoupler. The schematics are on this site,

 

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Discussion Starter · #5 ·
The Alta is an electric dirt bike with a 5.8kw pack. As a dirt bike, a lot of the areas they are ridden doesn't have AC power available. Places like motocross tracks, back woods trails, middle of the desert... If I can power it from DC it will save me having to have an inverter or a generator to charge the bike. I already have 10kw and 27kw CALB packs so if I can just use DC it saves me from using an inverter and would be more efficient.

Not sure I understand your circuit description. I did aviation electronics, but that was 40 years ago, so calling me rusty would overstate my circuit analysis capabilities. As for software, very little experience and I didn't even think about it when I asked the question. I did look at the schematics I found here. It looks like it may work, but the transformer on the input may stop it from working, but not sure. With DC it may just act as an inductor and smooth out the ripple that is not there. Other than the transformer it seems to dump right into the rectifier which should pass the DC, but again that is 40 year old rusty electronic knowledge and without thinking about the software.

Thanks for the help, I appreciate it.

Bluefxstc
 

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The Alta is an electric dirt bike with a 5.8kw pack. As a dirt bike, a lot of the areas they are ridden doesn't have AC power available. Places like motocross tracks, back woods trails, middle of the desert... If I can power it from DC it will save me having to have an inverter or a generator to charge the bike. I already have 10kw and 27kw CALB packs so if I can just use DC it saves me from using an inverter and would be more efficient.

Not sure I understand your circuit description. I did aviation electronics, but that was 40 years ago, so calling me rusty would overstate my circuit analysis capabilities. As for software, very little experience and I didn't even think about it when I asked the question. I did look at the schematics I found here. It looks like it may work, but the transformer on the input may stop it from working, but not sure. With DC it may just act as an inductor and smooth out the ripple that is not there. Other than the transformer it seems to dump right into the rectifier which should pass the DC, but again that is 40 year old rusty electronic knowledge and without thinking about the software.

Thanks for the help, I appreciate it.

Bluefxstc
Well, I don't understand what you are saying. You plan to hook a battery to the charger to charge the motorcycle? I still don't believe it will work because of the L4981AN powerfactor controller chip. It is looking for AC voltage.
 

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Well, I don't understand what you are saying. You plan to hook a battery to the charger to charge the motorcycle? I still don't believe it will work because of the L4981AN powerfactor controller chip. It is looking for AC voltage.
Why don't you use a DC to DC converter?
 

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Discussion Starter · #8 ·
Why don't you use a DC to DC converter?
I don't think a DC to DC converter will work without substantial modifications to the bike due to the bikes BMS and various control units. The charger and the bike are connected via CAN. They are all are talking to each other so removing any component stops the process.

Yes, the goal if it would work would be to hook the charger directly to DC. In the charger everything past the rectifier is DC anyway and I have done this in the past with Vicor power supplies. Now we either use a generator (gas fuel and noise) or a battery pack and an inverter (less efficient and more cost). I was hoping that maybe we could bypass the inverter and just use the DC at a suitable voltage. The charger has a voltage range of about 85-280 AC or about 65-195 RMS. I was hoping to be able to supply a 150-200 VDC pack to the charger and have it work. If it would work then the CAN communication between all the bike components and charger would continue to operate normally.

Thanks again for all the help and input.
 

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I don't think a DC to DC converter will work without substantial modifications to the bike due to the bikes BMS and various control units. The charger and the bike are connected via CAN. They are all are talking to each other so removing any component stops the process.

Yes, the goal if it would work would be to hook the charger directly to DC. In the charger everything past the rectifier is DC anyway and I have done this in the past with Vicor power supplies. Now we either use a generator (gas fuel and noise) or a battery pack and an inverter (less efficient and more cost). I was hoping that maybe we could bypass the inverter and just use the DC at a suitable voltage. The charger has a voltage range of about 85-280 AC or about 65-195 RMS. I was hoping to be able to supply a 150-200 VDC pack to the charger and have it work. If it would work then the CAN communication between all the bike components and charger would continue to operate normally.

Thanks again for all the help and input.
That same company makes can controlled dc to dc converters. DC/DC_Products_TIECHENG Technolgoy
 

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Discussion Starter · #10 ·
That same company makes can controlled dc to dc converters. DC/DC_Products_TIECHENG Technolgoy
All the DC to DC converters I saw on the site were 13.8Vdc output. The bike has a 350 Vdc pack so I don't think those will work, but I have sent them an email to ask if they do have a charger that would work.

Good idea, thanks for the link.
 

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Out of curiosity why would you use DC? AC is everywhere. DC sources are hard to come by..... That being said, the TCCH charger is power factor controlled. It uses an L4981AC Power Factor control chip https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjuwOOYqPHtAhUPwFkKHfBMBtoQFjACegQIBhAC&url=https://www.st.com/resource/en/application_note/cd00003936-designing-a-high-power-factor-switching-preregulator-with-the-l4981-continuous-mode-stmicroelectronics.pdf&usg=AOvVaw0fMaGeFFJeMThldGVxvlF1

I am not a real good analog designer so not sure how this chip would work on DC. It doesn't appear the software would stop you its looking at this voltage with an op amp through an optocoupler. The schematics are on this site,

I have done this numerous times with small 120vac-5 or 12vdc power adapters to operate temp gauges and other accessories from 50-80vdc battery packs. Saves the cost of buying a dc-dc converter. I tried to do this with a nice 3kw Brusa EV charger but no luck. Too much intelligence on the ac sensing side. The reason to do this is if try to charge from another battery pack or directly from solar. I do so at an off-grid cabin in the Sierras.
 
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