PROJECT TITLE :

A Decoupled Control Strategy of Modular Multilevel Matrix Converter for Fractional Frequency Transmission System - 2017

ABSTRACT:

Fractional frequency transmission system (FFTS), also referred to as low-frequency ac transmission system, is a promising solution to offshore wind power integration. The ac/ac converter is the foremost necessary equipment in FFTS. The modular multilevel matrix converter (M3C) is widely thought to be the subsequent-generation ac/ac converter, however its complicated control remains a problem. A novel management strategy is proposed that includes its decoupling algorithm during this paper. Totally different from previous research, the proposed current management regulates current parts of various frequencies separately in star-figure subconverters underneath their synchronous rotating frames (SRFs), where this is remodeled to dq-axis dc signals for a higher performance. A unique algorithm named “cross-SRF decoupling algorithm” is proposed to beat the tight coupling between the circulating currents of two completely different frequencies. The effectiveness of the proposed control strategy has been verified by the simulation results obtained from a 110 kV, four hundred MW M3C system implemented in MATLAB /Simulink.