Need to know the motor characteristics:
1) The current of the motor under the same voltage, different loads and different speeds, inductively understand the influence of the back EMF of the motor on the current.
2) Understand the phase relationship between the electric phase and the current of the motor, and how the motor itself can achieve commutation.
Motor hardware: PWM frequency selection, N-tube model selection, etc. If it involves an H-bridge, it is recommended to learn how to build an H-bridge and the selection of key components. Motor control: software overcurrent protection, how PWM is generated, and the influence of different PWMs on the motor can be added.
2. Stepper motor control (5 wires) It is recommended to use a 5-wire stepper motor (with a common line) in this process, because the circuit is simple and easy to drive, and it can be driven by using a Darlington tube (UNL2003). This process should be able to realize motor speed control, overcurrent protection, etc. Motor: The principle and stepping principle of multiphase motor Hardware: MCU is no longer controlled by an IO port, and 4 IOs are needed to control the motor.
Software: Realize motor speed regulation to ensure that the motor does not lose steps.
3, stepper motor control (4 wires) This process mainly learns H bridge, motor winding, to achieve motor forward and reverse rotation and speed control, motor: mainly learn motor winding hardware: H bridge and key device selection, at this time to start paying attention to the dead zone software: H bridge PWM generation, dead time and so on.
4. The main part of the three-phase motor square wave control is to learn: motor: the winding of the motor. To understand the difference between BLDC and PMSM, it is recommended to use PMSM.
Hardware: How to build and understand the 3 half-bridges, it is recommended to learn the drive circuit of the high bridge, understand the principle of pre-charging, etc. Of course, it is possible that using a PN tube does not require pre-charging. Software: 1) For sensing: commutation can be realized according to the information feedback from Hall. Realize the normal operation of the motor.
2) For non-inductive: 1> learn 3-stage start, 6-step commutation method 2> learn freewheeling shielding 3> understand the principle of motor position detection, and can realize the motor 4 > and sensible comparison, understand the commutation point, the relationship between the motor back EMF and the Hall position (motor rotor) 5, FOC control is good, the first 4, even if you do not have any mathematical knowledge, you can also achieve the operation of the motor through simple perceptual understanding. But when you get to the FOC, you start to enter modern automatic control, and you will use the advanced numbers, linear algebra, differential equations, and automatic control principles you learned in undergraduate. The previous control was basically a black box control, and basically a PID control could solve all control problems. But when you enter FOC, you begin to enter modern automatic control (some people call it advanced automatic control). The most basic feature of modern automatic control is model-based control. We want to model every object we control. How to build a model? Differential equation. How to solve differential equations: numerical analysis, various observers. Is the control object stable? Whether there can be a solution to a differential equation. Let's start introducing FOC (Background Knowledge of Modern Control)