A common-mode voltage suppression method for dual inverters based on 60-degree coordinate system

Abstract

The invention discloses a common-mode voltage suppression method based on a 60-degree coordinate system open-winding dual-inverter space vector modulation, which achieves the effect of common-mode voltage suppression by changing the duty cycle of a specific vector combination. In this method, every time the switching state is changed, the switching tube only changes once and the mutual difference of the common-mode voltage generated by adjacent switching sequences is the minimum value of the generated common-mode voltage value, which reduces the switching frequency of the system and reduces the current and torque ripple. , to achieve the effect of dynamic common-mode voltage suppression, which essentially solves the problems of common-mode voltage in the open-winding dual-inverter topology, and reduces the current harmonic content and torque ripple when the permanent magnet motor is running.

Description

technical field [0001] The invention relates to a common-mode voltage suppression method of open-winding double inverters based on space vector modulation, and belongs to the field of permanent magnet motor control. Background technique [0002] Compared with the topology of the traditional three-level NPC inverter and the leap capacitor inverter, the open-winding dual-inverter topology reduces the number of switching devices, and there is no such problem as the capacitor midpoint voltage offset; at the same time, Compared with the traditional single-inverter structure, the fault-tolerant performance is also greatly improved. When a single-tube fault occurs in the inverter, the fault-tolerant control strategy can be implemented without online reconfiguration, which greatly improves the reliability of the drive system and also The utilization rate of the DC side voltage is greatly improved. These advantages make open-winding dual inverters widely used in electric vehicle dri...

AI Technical Summary

Problems solved by technology

[0003] Technical problem: The present invention is based on the open-winding dual-inverter driving system for electric vehicles, and aims at the common-mode voltage suppression problem of the open-winding dual-inverter driving system, and proposes a common-mode voltage based on the 60-degree coordinate system SVPWM The suppression method solves the problem of large system switching loss in the traditional common-mode voltage suppression method, improves the sine degree of the current, reduces the torque ripple, and solves the low DC voltage utilization rate of the specific vector suppression common-mode voltage method At the same time, the control algorithm can be greatly simplified, the corresponding speed can be improved, and the effect of dynamically suppressing the common-mode voltage can also be achieved.

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