Fuzzy control method of direct current transmission converter based on command filtering

Abstract

The invention discloses a fuzzy control method of a direct current transmission converter based on command filtering. A fuzzy logic system is employed to approach unknown nonlinear terms in a power grid side converter system of a voltage source type direct current transmission converter system. A command filtering technology is introduced to solve the inevitable problem of 'calculation explosion'in the back-stepping control technology, the error of the filter is reduced by introducing a filtering compensation mechanism, and the command filtering technology has good inhibition effect on higherharmonics; the problems of unknown system parameters and uncertain disturbance intervention can be solved by introducing a self-adaptive control technology; under the control method of the invention,only one self-adaptive parameter exists in the controller, thereby reducing the on-line calculation burden and facilitating engineering practice. Simulation results show that the method can achieve quick and stable response to power and can achieve control of the power grid side converter.

Description

technical field [0001] The invention belongs to the technical field of direct current transmission converter control, and in particular relates to a command filter-based fuzzy control method for direct current converters. Background technique [0002] Since the 1950s, high-voltage direct current transmission technology has developed rapidly. High-voltage direct current transmission has the advantages of fast adjustment, small transmission loss, stable operation and strong self-protection ability. A voltage source DC transmission converter will be used to connect to the grid. Due to the existence of a large number of nonlinear components in the power system, the high-voltage direct current transmission system is a nonlinear system. Non-linear components are often used in power equipment, which leads to high-order harmonics in the power grid. In actual engineering, in order to suppress high-order Sub-harmonics are often added by means of adding filters, and at the same time, ...

AI Technical Summary

Problems solved by technology

Due to the existence of a large number of nonlinear components in the power system, the high-voltage direct current transmission system is a nonlinear system. Non-linear components are often used in power equipment, which leads to high-order harmonics in the power grid. In actual engineering, in order to suppress high-order Sub-harmonics are often installed by means of adding filters, and at the same time, there are uncertain disturbances in the converter system. The above conditions make the traditional system controller design method often unable to meet the actual engineering requirements.

Images