Dual-sliding mode control based speed regulating system and method for direct torque of permanent magnet synchronous motor main axis

Abstract

The invention provides a dual-sliding mode control based speed regulating system and method for direct torque of a permanent magnet synchronous motor main axis. The speed regulating method comprises the following steps: calculating the torque of the motor main axis according to the difference value of the actual rotating speed of the permanent magnet synchronous motor main axis and the given rotating speed of the permanent magnet synchronous motor main axis as a given value of a PI regulator; detecting the stator current and voltage of the motor main axis by using a sensor, observing the fluxlinkage and torque of the motor main axis under a stator coordinate system, comparing observed values with the torque calculated by the PI regulator and the given flux linkage respectively, obtainingdirect axis voltage and quadrature axis stator voltage by using the difference value through a dual-sliding mode controller, acting on a power switch device on a main circuit inverter through coordinate conversion and SVPWM conversion, and thus realizing direct torque control of the permanent magnet synchronous motor main axis. The speed regulating system is simple in structure, easy to realize and good in robustness, and has the advantages of high torque response speed and small tracking error, so that the stability of the system and the machining precision of parts are improved.

Description

technical field [0001] The invention belongs to the technical field of numerical control machining, and in particular relates to a permanent magnet synchronous electric spindle direct torque speed regulation system and method based on double sliding mode control. Background technique [0002] As one of the core components of high-precision CNC machine tools, permanent magnet synchronous electric spindle has the advantages of simple structure, high power factor, good low-speed performance, and low loss. It is widely used in occasions requiring high precision and high reliability. Direct torque control is a comprehensive control of flux linkage and torque centered on torque. Unlike vector control, direct torque control does not require decoupling. It adopts the concept of stator flux orientation and space vector, and through the stator voltage Carry out integration, directly observe the flux linkage and torque of the motorized spindle in the stator coordinate system, and compa...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the large flux linkage and torque pulsation caused by the traditional direct torque control strategy of the existing permanent magnet synchronous electric spindle, the system is difficult to accurately control at low speeds, and the noise and chattering caused by flux linkage and torque pulsation etc., the present invention provides a permanent magnet synchronous electric spindle direct torque speed regulation system and method based on double sliding mode control, which is used to reduce the fluctuation of flux linkage and torque, improve the dynamic and static performance of the system, and ensure the CNC machining accuracy

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