Servo systems use torque control in two ways: one where the servo speed decreases as torque increases, and another where the servo speed increases as torque increases, maintaining the speed once the set torque is reached. There are two types of loads for torque control: one where torque increases with speed (in which case torque control would automatically reduce the speed to lower the output torque to the set level); and another where torque decreases with speed (in which case torque control would automatically increase the speed to lower the torque to the set level).
1. Torque control is the control of motor current. The magnitude of the motor current determines the load torque, and it is controlled by the motor itself when driving the load.
2. When dealing with loads that have lower torque at higher speeds, the load torque decreases as the speed increases, and the motor current will automatically decrease.
3. Speed control refers to the control of the motor power supply frequency and voltage, which can be manually controlled via a frequency converter;
4. For loads with higher speeds and greater torque, such as water pumps and fans, the torque increases and the current automatically increases with the speed.
5. It is particularly important to note here that when the load torque is small, the motor current decreases, which reduces the motor torque and drives the load. This process is the motor's inherent ability and cannot be controlled by anyone else!
6. It is particularly important to note here that when the load torque is large, the motor current increases, which in turn increases the motor torque and drives the load. This process is the motor's inherent ability and cannot be controlled by anyone else!
7. During closed-loop current control of the motor, when the load torque is small, the current cannot be lower than the given value. The motor frequency and voltage will automatically increase, and the load speed will increase the load torque.
8. During closed-loop current control of the motor, if the load torque is large and the current cannot exceed the given value, the motor frequency, voltage, and speed will automatically decrease to reduce the load torque;
9. If a load with increased deceleration torque is encountered, the result of current closed-loop control will definitely be stopping the vehicle;
10. If the load with decreasing speed torque is encountered, the result of the current closed-loop control will definitely be that the motor reaches its maximum synchronous speed or the generator operates.
