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C Type USB and Power Delivery 3.1

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Rarikao
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C Type USB and Power Delivery 3.1

Hello VESC community,

Do you think possible to add Power Delivery 3.1 (up to 240W 5Ax48V) management by the VESC STM32 processor?

Same connector for charge battery or VESC tool communication in case of USB connection.

I saw on ST web site that it should be possible without external component but I must check deeper this topic.

The final objectif will be to use this type of charger for charge battery using CC/CV procedure.

Target voltage and current can be received through CAN.

Negotiation result must be also sent over CAN for any external BMS system. 

Will be quite nice. Thanks in advance for any answer.

 

 

 

Rarikao
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Hi again, I saw another post asking for charger features and also USB C charger (20V 5A). This last is PD3.0 and is limiting to 20V and 100W

PD3.1 allow up to 48V 5A (connector current limit) so 240W. 48V can charge a lot of battery on many project without need of boost converter.

However, keeping boost converter management option is useful in case of low power USB charger as PD3.0 limiting to 20V.

We must check deeper the PD3.1 but as I remember, voltage can be set  with step of at least 0,1V enough for manage charge current regulation.

We have a project where this feature will be a big advantage and we are ready to economically contribute if the community is agree to do it.

As evaluation, I am using the free VESC tool with old VESC6. There is any information regard other versions? (Platinum, Gold,....) 

 

 

Rarikao

vadicus
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Good idea. Kind of a gimmick at 100w max charging output, but, well, people like small features like these. I will likely add this USB-C charging feature to my design very soon, it would be easy to do, just not the way it's described above. It would have to be a separate USB-C connector dedicated to charging wired directly to the ground and one of the phases with the USB-C pre-configured to always negotiate the highest voltage from the source (20v) for best efficiency (assuming battery voltage will always be above 20v). No need to tap into CAN or BMS, as the controller itself detects the connected source and starts charging. 

 

 

NextGen FOC High voltage 144v/34s, 30kw (https://vesc-project.com/node/1477)

Rarikao
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Hi Vadicus. I have already do this with external chip making charger negotiations with a preset value of 20V. The problem is that you can't know the charger power, it can be 45W, 60W, 96W, 100W,... and this make impossible to know with which current you can charge the battery you must set it manually. Also, I have add a stepUp DCDC stage because the battery is 8S and 20V is not enough. Actually the BMS don't manage the charge with CC (Constant Current) but CP (Constant power). In fact, due to step Up stage, I draw a constant power that the charger can deliver and the Step Up output current is decreasing when battery voltage is increasing.

Using PD3.1, the charge will be quite more efficient and faster because the 5A max current can be battery charge current adjusting the charger voltage in close loop and this up to max battery voltage. I also would like to keep the set Up stage in case of PD3.0 charger used (max 100W).

 

 

 

Rarikao

vadicus
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In my case, the controller doesn't care if it it's getting 5, 12, 20, or 48v. It only needs to know how much current it's allowed to pull, so I set let's say 5A max and forget about it. At 48v x 5A, that's going to be 240w, at 20v x 5A, that's 100W, etc. In fact, the only usable voltage would be really 20v and 48v in this case. I wouldn't even bother with charger that can't go over 5v or 12v.

 

 

NextGen FOC High voltage 144v/34s, 30kw (https://vesc-project.com/node/1477)