Three-phase voltage type rectifier and control method thereof

Abstract

The invention provides a three-phase voltage type rectifier and a control method thereof. Through providing the high-robustness three-phase voltage type rectifier, a better inhibition effect on both overshooting and steady state error of a system is achieved while the high utilization rate of the voltage of an electric grid is guaranteed. The three-phase voltage type rectifier and the control method thereof have the following advantages: 1, the utilization rate of the electric grid can be increased by 15.4% through adopting an SVPWM (Space Vector Pulse Width Modulation) method compared with that achieved by an ordinary PWM (Pulse Width Modulation) method; 2, a voltage loop adopts a sliding-mode variable structure control (VSC) algorithm to replace the traditional PID (Proportion Integration Differentiation) control algorithm, thus the three-phase voltage type rectifier can rapidly respond to the voltage change of a direct current side; and 3, the voltage loop adopts a PID and VSC combined control method to replace the traditional PID control algorithm, so that the three-phase voltage type rectifier can rapidly respond to current change and can output stable control signals, and then, the overshooting and steady state error of the direct current side are reduced.

Description

technical field [0001] The invention relates to a rectifier, in particular to a three-phase voltage rectifier and a control method thereof. Background technique [0002] Most of the converter devices widely used in various fields of the national economy require a rectifier to obtain a stable DC voltage. Harmonics and reactive power have caused serious grid pollution. The most fundamental measure to control this kind of grid pollution is to make the grid-side current of the converter device sinusoidal and the power factor to be 1. [0003] The application and development of PWM control technology provide revolutionary ideas and means for the improvement of rectifier performance. The new rectifier combined with PWM control technology is called PWM rectifier. Since the PWM rectifier realizes the sinusoidalization of the input current and operates at unity power factor, the energy can be transmitted bidirectionally, thus truly realizing the "green power conversion". [0004] ...

AI Technical Summary

Problems solved by technology

The control target of the vector control method is mainly the control of the current signal. The current control module in the vector control method has a high control sensitivity. The circuit parameters of the rectification system, the measurement delay and the performance of the phase-locked loop all have a great influence on the current control. , these factors cause the low robustness of the vector control method

[0006] The voltage loop and current loop of the usual three-phase voltage type rectifier mainly use PID regulators. When the circuit parameters, measurement delay and other factors change, the stability of the regulator will change significantly, increasing the regulator parameters. Difficulty in debugging, which brings practical difficulties to the debugging and implementation of rectifier applications

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