I am using a Trampa Vesc 6.4 for an efoil with a 12S battery. The vesc is rated 80Amp continuous and the motor detection wizard gave me 100 amp, so that vesc 6.4 seems to match pretty well the set up.
The motor is supposed to be rated at 150A/50V so about 7.5kW, but I am happy to use it at a max of 4kW.
I have program the Vesc with the motor wizard detection as FOC using a PWM signal in current no reverse mode.
The issue I have is that the motor current is so much higher than teh battery one, like I am getting 100amp output with 40 amp input so the max power I can draw is about 2kW, and the Mosfet heats pretty quickly. (see below logging). The Trampa Vesc works very well as it reduces by itself the power to avoid overheating, but I was wondering if there is a set up that would reduce the motor current for the same power (I guess increasing the motor voltage) in order to potentially get more power out of the motor as well as generating less heat on the mosfet as even at 1kW with no specific cooling outside the factory heatsink, I quickly reach the max temperature .
https://vesc-project.com/sites/default/files/imce/u20439/test-motor.JPG
Hi,
VESC amper rating is referring to the motor amperage afaik. Brushless controllers are basically a sophisticated DC-DC converters that make the output current very much like an AC curernt. So the 2 currents rarely match, its completely normal.
Power input*efficiency=power output. High battery voltage requires low batt amperage to achieve high current at the motor at slow speeds. At high speeds and high motor current the battery current will be high too. So if you would like to utilize vesc better you may need a gearing to increase motor speed for the same vehicle speed. Or smaller prop.
You are mechanically limited here, not electrically. Use gearing or smaller / lower pitch prop.