An open-winding permanent magnet synchronous motor drive system and its control method

Abstract

The invention discloses a low-cost open-winding permanent magnet synchronous motor drive system. A three-phase nine-switch converter comprises three phase bridge arms, which are connected with one another in parallel, wherein each phase bridge arm comprises an upper tube, a middle tube and a lower tube, which are sequentially connected with one another; the upper tubes and the middle tubes form an upper three-phase power output port; the middle tubes and the lower tubes form a lower three-phase power output port; a DC side of the three-phase nine-switch converter is connected with a DC power supply in parallel; the upper three-phase power output port and the lower three-phase power output port are connected with two ends of three phase windings A, B, C of an open-winding permanent magnet synchronous motor respectively; two ends of any phase winding of the open-winding permanent magnet synchronous motor are connected with different bridge arms; a current signal and a voltage signal of the open-winding permanent magnet synchronous motor are collected respectively and transmitted into a control module to achieve rotating speed current double closed-loop control; and a drive module outputs a PWM signal to achieve control on the three-phase nine-switch converter. The system is low in cost and good in speed control performance. The invention further discloses a control method for the low-cost open-winding permanent magnet synchronous motor drive system.

Description

technical field [0001] The invention belongs to the field of motor systems and controls, in particular to an open-winding permanent magnet synchronous motor drive system and a control method thereof. Background technique [0002] The open-winding structure motor opens the neutral point of the traditional three-phase AC motor to form an open winding structure with two ports. The magnetic circuit and structure of the motor do not change. The open-winding structure motor does not change the basic performance of the traditional motor, and After the neutral point is opened, the constraint relationship between the traditional motor windings of each phase no longer exists, and the windings of each phase are independent, which can improve the reliability of the motor body to a certain extent, and its two ports can be connected to the converter respectively. The coordinated control of the converters at the ports can make each converter bear half of the power, and the converters at bo...

AI Technical Summary

Problems solved by technology

At present, the permanent magnet synchronous motor is the first choice for the motor drive system with high power density, high efficiency, and high performance. The open-winding structure permanent magnet synchronous motor combined with the corresponding power converter can constitute a drive system with excellent characteristics. However, the existing The dual-inverter and its derivative multi-level inverter topology suitable for motors with open-winding structure, although the drive control function can be well realized, but the converter topology with more than 12 switching devices greatly increases the drive system The cost of the open-winding permanent magnet synchronous motor drive system is relatively high, and the complexity of the control system is relatively high. Therefore, it is an important way to promote its application field by studying its simplified converter topology and its control technology.

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