Motor Controller - What might be the purpose of these resistors?
I was looking at the video of the Tesla Model 3 motor controller(400VDC, 500A) disassembly and noticed a resistor network as in the picture below. They are 2k resistors(SMD code 202).
See the picture below:
I was wondering what might be the reason for putting these resistors in a motor controller unit?
Some of the reasons I have been thinking of:
- Bleeding resistors for the input bulk capacitance when the controller is disconnected from the main battery
- Dissipative brake when the motor is acting as a generator in order to mitigate the overvoltage on the bus.
Here is the video if you are interested video link - I've linked the part where resistors are zoomed in.
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