1. Magnetic flux adjustment control
Flux adjustment control is to achieve the purpose of controlling the speed and torque by changing the strength of the stator flux of the motor. In fact, the flux is generated by the stator current, so the flux strength is directly related to the motor power supply. If the power supply voltage is reduced, the magnetic flux density decreases, and the speed and torque of the motor also decrease. If you increase the supply voltage, the magnetic flux density increases, and the speed and torque of the motor increase accordingly. Therefore, flux regulation is one of the simplest but imprecise motor control methods.
2. Resistance control
Resistance control is a control method designed for the characteristics of DC motors under different voltages. By adding a rheostat in the line, the voltage supplied to the motor can be reduced, reducing the voltage at which the motor is turned on. When the motor voltage decreases, its speed and torque will also decrease. While this control is simple, it's still one of the least precise.
3. Potential modulation control
Potential modulation is the most common control method for DC motors. Its principle is to change the duty cycle of the output voltage of the computer board through PWM modulation to achieve the purpose of changing the motor speed and torque. PWM is a modulation method, which will control the electric pulse generated by the chip through the combination of different periods and duty cycles, and finally generate an output equivalent to the voltage. By adjusting the duty cycle of the PWM, the speed and torque of the motor can be controlled, so the potential modulation has become a main method of motor control.
4. Conveyor belt control
Conveyor belt control is a control method designed for the rotation or transportation of objects supplied by the motor. This control method is to affect the speed and position of the object by changing the voltage and speed of the motor, making it stop, adjust or displace in a specific area. The advantage of this control method is that the circuit control of the motor is very precise, and a very accurate control effect can be obtained, focusing on controlling the transportation of objects and preventing wear and tear.
Generally speaking, the control principle of DC motor involves many aspects. The control methods listed above are only the most basic principles. In practical applications, these control methods often achieve wider control range and effects through compound applications. However, for DC motor control design, we always choose the most suitable control method. In fact, because of the reliability, high efficiency and flexibility of DC motors, controlling DC motors has become the mainstream of current motor design.
