Low harmonic suppression method for four-quadrant converter device of electric locomotive

Abstract

The invention belongs to the field of control, relates to a control algorithm for current low-order harmonic suppression of a four-quadrant converter, and specifically relates to a low harmonic suppression method for a four-quadrant converter device of an electric locomotive. The method is a harmonic suppression method fused in a four-quadrant control algorithm. The problem that the current low-order harmonic of a four-quadrant converter influences the control of the converter and pollutes the power quality of a power grid is solved. The problem of influence caused by low-order harmonic filtering by adopting a software filter method is solved. The problem of certain influence on four-quadrant control dynamic performance and harmonic suppression capability due to low calculation precision of the fundamental wave phase angle and the low-order harmonic phase angle of a power grid voltage signal is also solved. According to the method, harmonic extraction and suppression functions are added to a four-quadrant converter control algorithm, the method has high adaptability and flexibility, and the purpose of high-precision harmonic suppression can be achieved.

Description

technical field [0001] The invention belongs to the field of control, in particular to a control algorithm for suppressing low-order current harmonics of a four-quadrant converter, in particular to a method for suppressing low-order harmonics of a four-quadrant converter for electric locomotives. Background technique [0002] Four-quadrant rectifiers are widely used in electric locomotives because of their high power factor and the ability to realize bidirectional flow of energy. Due to the low switching frequency of the four-quadrant rectifier, its AC side current usually has poor harmonic characteristics, which brings harmonic pollution to the power supply network, thereby affecting the power quality of the power supply network and the grid environment when other locomotives are running. [0003] In practical applications, four-quadrant converters usually use various methods to reduce the pollution caused by current harmonics. The main circuit topology of four-quadrant con...

AI Technical Summary

Problems solved by technology

[0006] The invention provides a harmonic suppression method integrated in the four-quadrant control algorithm, which solves the problem that the low-order harmonics of the current of the four-quadrant converter affect the control of the converter and pollute the power quality of the power grid, and at the same time It solves the problem of using the software filter method to filter out the influence of low-order harmonics, and also solves the problem of low calculation accuracy of the fundamental wave phase angle and low-order harmonic phase angle of the power grid network voltage signal, which causes the four-quadrant control dynamics Issues that have a certain impact on performance and harmonic rejection

Images