Current Predictive Control Method of Permanent Magnet Motor Based on Zero-Order Preserving Discretization Model

Abstract

The invention discloses a permanent-magnetism motor current predication control method based on a zero-order holding discrete model. The method comprises the following steps that on the basis of the zero-order holding discrete model of a permanent-magnetism motor, a time delay item as well as a disturbance item is introduced and calculated, and a permanent-magnetism motor time delay model and a permanent-magnetism motor disturbance model are obtained; on the basis of the permanent-magnetism motor disturbance model, an expansion state observer is designed in a state space method; the current change rate and the current change amount caused by a voltage vector are obtained according to the expansion state observer, a control law is obtained according to the current change rate, the current change amount and the voltage vector, and a controller is further obtained; and according to the permanent-magnetism motor time delay model and the controller, a state equation of an electric tractionclosed-loop system when the observer is not taken into consideration is calculated, and a feedback coefficient of the observer is designed. According to the invention, the discrete current predictioncontroller and observer are designed via the state space method, and a current control performance of the permanent magnetism motor is improved.

Description

technical field

[0001] The invention relates to the technical field of motor control, in particular to a current predictive control method of a permanent magnet motor based on a zero-order hold discretization model. Background technique

[0002] The ever-increasing application requirements put forward higher requirements for the permanent magnet motor control technology, requiring it to have excellent dynamic and static response characteristics and strong robustness under complex working conditions. Different from traditional vector control, model predictive control seeks the optimal control quantity in each sampling period, and has a good application prospect in the field of permanent magnet motor current control. Model predictive control is based on the mathematical model of the motor and inverter, combined with the current given value and the actual current sampling value at the current moment, and calculates the optimal control quantity according to the cost function and...

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