Method to reduce common mode voltage of svpwm motor

Abstract

The invention discloses a method for reducing the common-mode voltage of an SVPWM motor. S1: Obtain the voltage under the static voltage coordinate system from the previous stage control link; S2: Apply the voltage under the static voltage coordinate system in step S1 to select the action vector voltage; S3 : select the inverse vector voltage; S4: recalculate the inverse vector voltage time according to the inverse vector voltage determined in step S3; S5: determine the switching point of the sector vector. In the present invention, the voltage opposite to the action vector in SVPWM is used to replace the zero vector, which is used to suppress the excessively high common-mode voltage of SVPWM. When the SVPWM is driving the motor, the excessively large common-mode voltage exists to break down the insulating oil film and cause a short circuit between shafts, even burning The hidden danger of bad motors, rapid common-mode voltage changes will also produce strong electromagnetic interference, affecting the stable operation of other nearby devices, reducing the size of the common-mode voltage can effectively prevent the motor from being damaged when the common-mode voltage is too high. The damage of the motor can prolong the life of the motor, improve the operating efficiency of the motor, and reduce the failure rate.

Description

technical field [0001] The invention relates to the technical field of SVPWM motors, in particular to a method for reducing the common-mode voltage of the SVPWM motor. Background technique [0002] Nowadays, motors are instruments that we often come into contact with in our lives. Whether it is a spacecraft or a submarine that dives tens of thousands of meters deep under the sea, motors are needed to execute the parts that need to move in the equipment, so the requirements for motor control technology are very important. Among them Three-phase motors are widely used in industrial and military fields. The main method of controlling three-phase motors is Space Vector Pulse Width Modulation (SVPWM) technology. SVPWM has a common-mode voltage when driving the motor, which will make the motor aging, Heat generation, noise aggravation, excessive common-mode voltage may even break down the insulating oil film and cause a short circuit between shafts, and even burn out the motor. Ra...

AI Technical Summary

Problems solved by technology

[0004] 1. Increase the cost of use and reduce production efficiency;

[0005] 2. The failure rate of devices has been increased. The increase of devices will lead to more failure points, because transistors are often used in complex situations and are easily affected by the external environment. Device damage;

[0006] 3. Increased the difficulty of troubleshooting. Due to the large number of devices, it is impossible to quickly check whether it is a problem with the main control device or an auxiliary device.

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