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I want to perform a speed control for a 1500W brushless DC motor. The documentation and videos I've seen use arduino uno and are for smaller engines. I would like to carry out this project without using arduino uno.

Could someone recommend me books with examples of controls for brushless DC motors?

On the other hand I have found contradictions between PWM and ESC. Are the ESCs for brushless DC motors and the PWM for brushed DC motors? Or is it indistinct?

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  • \$\begingroup\$ ESC is a device ... PWM is a form of signal encoding \$\endgroup\$ – jsotola Feb 13 '20 at 19:18
  • \$\begingroup\$ PWM is a type of voltage waveform that can be used for all motors. ESC is a specific device that uses such a waveform for brushless motors, specifically for RC hobby brushless motors. You don't hear the term ESC anywhere outside of RC. \$\endgroup\$ – DKNguyen Feb 13 '20 at 20:19
  • \$\begingroup\$ @DKNguyen There are ESC for brushed motors as well, maybe more then for brushless, until just a few years ago \$\endgroup\$ – Maple Feb 15 '20 at 6:43
  • \$\begingroup\$ @Maple Ah, yes. Before my time. But my main point was you don't hear ESC anywhere outside the RC hobby industry. If you use the term ESC, an engineer who has no experience with the hobby industry might not know what you're talking about. Motor driver is the more commonly understood term (as well as a myriad of more specific ones). \$\endgroup\$ – DKNguyen Feb 15 '20 at 17:26
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ESCs are used for brushless DC motors (BLDC). But PWM is used in both DC and BLDC. The topology of a ESC consists of a 3-phase inverter with back emf feedback to know when to switch (complicated circuitry).

Commercial ESCs are designed with a PWM signal input. This happens to be the same as per the servo motors. They take a 50Hz PWM that ranges from 5% to 10% Duty Cycle. 5% being the motor is off and 10% the motor is going at max rpm.

Brushed DC motors have a minimum operating voltage, so the minimum duty cycle must be chosen carefully as it may lead you to waste power when the motor is not moving. Usually brushed DC motors have 2 signal wires and an enable pin. The PWM would be connected to the enable pin. Every IC is different so always look at the datasheet of your chosen motor driver.

I can't help with book recommendations but you may want to have a look in a library for "electrical machines" with "drivers" and "fundamentals" or "principles" as your main keywords.

Summarizing: PWM is used in both BLDC and DC motors for speed control.

Hope this answer your question about PWM.

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PWM means Pulse Width Modulation, which is a method used in many power electronics applications to get a variable output voltage from a fixed input voltage. ESC means Electronic Speed Controller, the thing that converts the battery DC voltage to the Ac voltage your motor needs using PWM.

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