Current detection method based on fault tolerance and alternating-current motor servo control method

Abstract

The invention discloses a current detection method based on fault tolerance and an alternating-current motor servo control method. The current detection method comprises the following steps: two current sensors are installed in a three-phase full-bridge inverter circuit, and each current sensor detects the current values of two lines at the same time, wherein the two lines detected by one sensor are respectively a connecting line of phase-A and phase-B upper bridge arms and a connecting line of phase-B and phase-C lower bridge arms, and the two lines detected by the other sensor are respectively a connecting line of phase-A and phase-B lower bridge arms and a connecting line of phase-B and phase-C upper bridge arms; and switching-on / off of power tubes in the three-phase full-bridge inverter circuit is controlled, and the current values of three-phase windings are obtained according to current values detected by the two current sensors at the same time or current values detected by the same current sensor at different times and the Kirchhoff's current law. According to the invention, fault tolerance control of alternating-current motor winding phase current detection can be completed on the premise of not increasing the cost of the hardware circuit, the structure is simple, and cost is reduced.

Description

technical field [0001] The invention relates to the field of drive control of AC motors, in particular to a current detection method based on fault tolerance for AC motors and a servo control method for AC motors. Background technique [0002] In recent years, with the development of power electronics technology, microcontroller technology, motor manufacturing process and the emergence of new materials, the servo system with AC motor as the actuator has made great progress, and has gradually replaced the traditional hydraulic and DC systems as servo systems. mainstream of the system. AC servo systems can be divided into induction motors and permanent magnet synchronous motors according to the actuators. Among them, permanent magnet synchronous motors have gained more and more scientific research because of their simple structure, small size, high efficiency, high control accuracy, and good reliability. It is favored by personnel and widely used in occasions that require hig...

AI Technical Summary

Problems solved by technology

[0004] The present invention provides a current detection method based on fault tolerance and an AC motor servo control method to solve the problem that the phase current detection of the existing AC motor winding has no fault tolerance or the number of sensors is large, the structure is complex, and the cost is high due to fault tolerance. technical issues

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