1500 AMP Homemade Motor Controller Test 2

This time I have a much larger motor Advanced DC motor and better battery cable connections and the motor controller doesn't seem to be phased at all.

Category:

Science & Technology

Tags:

• robomo
• robomo.com
• robot
• electric
• car
• truck
• homemade
• motor
• controller
• high
• amperage
• voltage
• arduino
• microcontroller
• linux

[Chuechco93]

What is your PWM frequency? Looks like its right within the range of human hearing. but seems to work well;)

[anewlow23]

@Chuechco93 Actually its 1khertz its about all these bipolar transistors can handle.Have you worked with arduino?

[Chuechco93]

@anewlow23 Yes I have. My plan is to build an electric go kart. I already bought a large DC forklift motor (maybe a bit overkill). next thing I want to do is to make the controller for it. 400 Amps is fine. Are you using IGBTs or MOSFETs? Do you have a schematic for the power unit?

[anewlow23]

@Chuechco93 They are darlingtons powerex model ks621k30 they were pretty cheap on ebay and I was surprised by the amount of current they could handle when driving my truck the only thing was you had to keep them at 1.5 khertz or below. Have you ever worked with micro controllers? I wanted to either use a pwm circuit out of a scooter or perfect the programming with arduino then use hardware overcurrent. 

[anewlow23]

@Chuechco93 I did not use overcurrent but for the hardware overcurrent I planned on using a nand gate and a latch. The PWM signal goes through the nand gate until a signal come from either the shunt or a hall effect at a certain voltage say 5v to the latch. Both leads of the nand receive a postive signal and the pwm stops for a brief time resetting the duty cycle when the amps are too high. I don't know how you would set different current limits though b/c of the latch.

[Chuechco93]

@Chuechco93 Yesterday I built up a 555 oscillator circuit and testet it with a simple NPN transistor that enables current flowing to a motor. It works pretty good although there are only 200mAmps flowing through the circuit. I think I won't be able to controll large motors with a simple 555 circuit since I need to watch current, voltage etc. I also have an arduino lying around here. It could defently do the job. Or I will buy an ATMEGA8 microcontroller which are very cheap.