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Vector control and vf control what is the difference, many novices are not very clear about this, in order to help you solve this problem, the following editor will explain in detail for you, people with this need can come to learn, I hope you can gain something.

The differences between vector control and vf control are as follows: (1) the characteristics of vector control are different, the speed or position of motor needs to be measured in vector control, and the accuracy of VF control torque is related to the motor parameters used in the control system; (2) the action mechanism of them is different; (3) the overview of the two is different.

First, the characteristics of the two are different:

1. The characteristics of vector control: the speed or position of the motor needs to be measured (or estimated). If the speed of the motor is estimated, parameters such as motor resistance and inductance are required. If it is possible to cooperate with a variety of different motors, automatic debugging programs are required to measure motor parameters. By adjusting the target value of the control, the torque and flux can be changed quickly, which can be completed in 5-10 milliseconds.

2. The characteristics of VF control: the accuracy of torque is related to the motor parameters used in the control system, so if the motor temperature changes, the error will increase when the rotor resistance increases.

Second, the action mechanisms of the two are different:

1. Vector control mechanism: speed control (ASR) in vector control makes the deviation between speed instruction and speed detection value (feedback of PG or speed estimation value) 0 by operating torque instruction.  

2. The action mechanism of VF control: the speed control with PG makes the deviation between speed instruction and speed detection value (feedback of PG or speed estimation value) 0 by operating the output frequency.

3. The overview of the two is different:

1. Summary of   vector control: the technology of using frequency converter (VFD) to control three-phase AC motor, by adjusting the output frequency of frequency converter, the magnitude and angle of output voltage, to control the output of motor. Its characteristic is that it can control the magnetic field and torque of the motor respectively, which is similar to that of the other excited DC motor. Because the three-phase output current and voltage are expressed as vectors during processing, it is called vector control.

2. Summary of VF control: VF control means that the ratio of output frequency to output voltage of frequency converter is constant or proportional. For example, when the output voltage of 50HZ is 380V and 25Hz, the output voltage of 190V is constant flux control; the torque is not controllable, the system is only a single closed-loop control system with speed physical quantity as closed loop, and it can only control the speed of the motor.

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