Electric motors play important roles in many industrial fields, such as packaging, food, beverages, manufacturing, pharmaceuticals, robots, etc. We can choose different performance, size, torque, accuracy, and speed from different motor models.
As the core component of driving and control, the motor test bench has shifted its application from simple driving to precise control with the advancement of technology, especially in accurately controlling the speed, position, and torque of the motor. But the structure and driving method of motors are also different. From the appearance, their selection is very complex, so they are divided into several categories according to their uses. Next, we will gradually introduce typical, commonly used, and basic electric motors – control motors, power motors, and signal motors. The control of the motor is mainly used for accurate speed and position control, and is the “actuator” of the control system. It can be divided into servo motors, stepper motors, torque motors, switched reluctance motors, DC brushless motors, etc.
1. Servo motors have been widely used in various control systems. They can convert input voltage signals into output power of the motor and control the motor by dragging the controlled components. Usually, servo motors need to control the speed of the motor, and with changes in voltage signals, the speed of the motor can be continuously adjusted; The torque can be controlled by the output current of the control device. The motor should have a fast response, small size, and low control power. Servo motors are widely used in various motion controls, especially in servo systems.
Servo motors are divided into two types: DC and AC. Servo motors are ordinary DC motors, but due to their low control accuracy, only ordinary DC motors can be used.
2. Stepper motor
A stepper motor is a mechanical device that converts a stepper motor into angular displacement. Simply put, it drives the motor to rotate in a certain direction when the stepper driver receives a pulse signal. The number of pulses can be used to control the angular displacement of the motor, achieve accurate positioning of the motor, and adjust the speed and rotation speed of the motor by controlling the pulse frequency. At present, stepper motors mainly include reactive stepper motors, permanent magnet stepper motors, hybrid stepper motors, single-phase stepper motors, etc.
The difference between stepper motors and general motors lies in their pulsation mode, while stepper motors can be combined with modern digital technology. However, stepper motors have poor control accuracy, speed variation range, low-speed performance, etc., so they are used in situations where accuracy requirements are low. Stepper motors have a simple structure, high reliability, and low cost, so they have been widely used in practical production, especially in CNC machining. Stepper motors do not require A/D conversion and can directly convert digital pulse signals into angular displacement. Therefore, they are known as the best actuators on CNC machine tools.
The motor test bench can be used not only for CNC machining, but also for other machines, such as automatic feeders, motors for general floppy disk drives, and printing and drawing machines.