Method for reducing common-mode voltage of SVPWM motor

Abstract

The invention discloses a method for reducing the common-mode voltage of an SVPWM motor. The method comprises the steps of S1, obtaining the voltage under a static voltage coordinate system from a preceding-stage control link; S2, selecting an action vector voltage by applying the voltage under the static voltage coordinate system in the step S1; S3, selecting an inverse vector voltage; s4, recalculating the inverse vector voltage time according to the inverse vector voltage determined in the step S3; and S5, determining a switching point of the sector vector. According to the invention, the voltage opposite to the action vector in the SVPWM is adopted to replace a zero vector to inhibit the over-high common-mode voltage of the SVPWM, the over-high common-mode voltage of the SVPWM breaks through an insulating oil film to cause an inter-shaft short circuit when the SVPWM drives the motor to cause the hidden danger of burning out the motor, and the rapid common-mode voltage change can also generate stronger electromagnetic interference, which affects the stable operation of other nearby devices, reduces the common-mode voltage, so that the motor is effectively prevented from being damaged under the condition that the common-mode voltage is too high, and the effects of prolonging the service life of the motor, improving the operation efficiency of the motor and reducing the failure rate are achieved.

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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