Balanced Current Control Strategy for Current Source Rectifier Stage of Indirect Matrix Converter under Unbalanced Grid Voltage Conditions

Abstract

This paper proposes a balanced current control strategy for the current source rectifier (CSR) stage of an indirect matrix converter (IMC) under unbalanced grid voltage conditions. If the three-phase grid connected to the voltage source inverter (VSI) of the IMC has unbalanced voltage conditions, it affects the currents of the CSR stage and VSI stage, and the currents are distorted. Above all, the distorted currents of the CSR stage cause instability in the overall system, which can affect the life span of the system. Therefore, in this paper, a control strategy for balanced currents in the CSR stage is proposed. To achieve balanced currents in the CSR stage, the VSI stage should receive DC power without ripple components from the CSR stage. This is implemented by controlling the currents in the VSI stage. Therefore, the proposed control strategy decouples the positive and negative phase-sequence components existing in the unbalanced voltages and currents of the VSI stage. Using the proposed control strategy under unbalanced grid voltage conditions, the stability and life span of the overall system can be improved. The effectiveness of the proposed control strategy is verified by simulation and experimental results.

Blackbox Large-Signal Modeling of Grid-Connected DC-AC Electronic Power Converters

“…(3) Finally, it has been mentioned that this work assumes that the converter is balanced. However, in applications such as microgrids, the analysis of unbalanced systems has become an important issue [37][38][39]. In case unbalanced systems should be taken into account, the positive and negative sequences should be considered in the model structure.…”

Harmonic Analysis and Attenuation Strategy for a Two-Stage Matrix Converter Fed by Dual-Inverter Based on Pulse Barycenter Method

“…The topology of TSMCs can be divided into the rectifier stage and inverter stage. There is no energy storage element in TSMCs, compared with AC-DC-AC converters, which reduce the volume and weight, improve the reliability, and prolong the life of the system [1][2][3]. TSMCs have great superiority in the field of aerospace and military equipment, where the requirement of the converter volume is strict.…”