Constant direct-axis current control method and system of embedded permanent magnet synchronous motor

Abstract

The invention discloses a constant direct-axis current control method and system of an embedded permanent magnet synchronous motor, and belongs to the technical field of motors. According to the constant direct-axis current control method and system disclosed by the invention, a coordinate original point O and an intersection point A of a limited current circle and a quadrature-axis current form constant direct-axis current control of a constant torque output region, an intersection point of a straight line perpendicular to a direct-axis current and extending from a center C of a voltage limited oval of a control region of the embedded permanent magnet synchronous motor and a center point B of the voltage limited oval form constant direct-axis current control of a constant power output region, a phase current, a phase voltage and a rotational speed of the embedded permanent magnet synchronous motor are detected according to a target rotational speed of the embedded permanent magnet synchronous motor, and the embedded permanent magnet synchronous motor is driven to work by utilization of the constant and invariable direct-axis current and an inverse relation between the quadrature-axis current and the rotational speed of the motor. The constant direct-axis current control method and system have the characteristics of fast response speed, high reliability and no speed limit control, and have good application prospects in the fields of new energy automobiles and the like.

Description

technical field [0001] The invention relates to an operation control system in the constant torque region and constant power region of a motor, more specifically, to a method and system for controlling a constant direct axis current of an embedded permanent magnet synchronous motor. Background technique [0002] The embedded permanent magnet synchronous motor can use the reluctance torque component to improve the speed regulation performance. It has the characteristics of high torque density, high efficiency, and wide speed regulation range. It can be used as a drive motor and has a wide range of applications in new energy vehicles and other fields. prospect. The existing control methods include the maximum output power control method and the maximum torque-to-voltage ratio control method, which are all nonlinear control methods. The maximum output power control method aims at the maximum power output. Although the decoupled direct-axis and quadrature-axis currents can be o...

AI Technical Summary

Problems solved by technology

The maximum output power control method aims at the maximum power output. Although the decoupled direct-axis and quadrature-axis currents can be obtained, the formula is very complicated and difficult to use in practical applications.

The maximum torque-to-voltage ratio control method has the direct-axis current and the quadrature-axis current cross-linked with each other, which is difficult to be applied in practice, so it greatly limits the speed regulation performance of the embedded permanent magnet synchronous motor in the constant torque region and constant power region

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