Permanent magnet synchronous motor discrete domain current loop control method introducing advanced beat current

Abstract

The invention belongs to the field of permanent magnet synchronous motor control and relates to a permanent magnet synchronous motor discrete domain current loop control method introducing advanced beat current. According to the method, a current controller is designed by utilizing a coefficient matrix F and an input matrix G of a discrete domain mathematical model of a permanent magnet synchronous motor under a rotating dq coordinate system, and the problem of angle lag caused by compensation digital control one-beat delay is considered. When a permanent magnet synchronous motor current loopis affected by disturbance signals, the oscillation amplitude in a dynamic process is reduced, the adjustment time is shortened, the anti-interference performance of a control system is improved, andthen the operation quality of the permanent magnet synchronous motor current control system is improved.

Description

technical field [0001] The invention belongs to the field of permanent magnet synchronous motor control, and provides a discrete-domain current loop control method of a permanent magnet synchronous motor that introduces an advanced beat current. Background technique [0002] Permanent magnet synchronous motors are widely used in high-performance drive applications such as new energy vehicles and industrial servo systems due to their high efficiency, high power density, specific power, and high starting torque. For many years, the proportional-integral (PI) controller based on the rotor field-oriented synchronous rotating coordinate system has been the industry standard for AC motor current control because of its wide speed range and zero steady-state error. However, the current commonly used current controllers will have the following problems when facing the high-speed and low-carrier ratio operation state: 1) The cross-coupling disturbance term introduced by the rotation c...

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Problems solved by technology

However, the current commonly used current controllers will have the following problems when facing the high-speed and low-carrier ratio operation state: 1) The cross-coupling disturbance term introduced by the rotation coordinate transformation between the d and q-axis subsystems increases with the increase of the operating speed However, the increase in height even becomes the main determinant factor of the d and q axis current components, which brings great disturbance to the control performance of the d and q axis subsystems; 2) limited by the allowable switching frequency and heat dissipation conditions of power devices, the corresponding The carrier ratio is low, which makes the discretization error prominent, the influence of sampling and control delay is aggravated, and even leads to system instability in severe cases

[0008] 1. The uneven air gap of the built-in permanent magnet synchronous motor makes the AC and direct axis inductance unequal, and the complex vector technology cannot be used to simplify the permanent magnet motor voltage model into a single-input single-output model. Based on the single-input and single-output control object described by the vector, the discrete domain design scheme of the current controller is not suitable for the built-in permanent magnet synchronous motor;

[0009] 2. The design of the discrete-domain current controller for the built-in permanent magnet synchronous motor reported in reference 3 has the problem that the current loop following performance and the anti-disturbance performance cannot be taken into account at the same time. When the current loop following performance remains unchanged, the disturbance signal When it works, the current will oscillate, the oscillation amplitude is large, and the adjustment time is long

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