Injection of Balanced Three-Phase Currents with Fuzzy Control of Three-Phase Bidirectional Csc Under Unbalanced Grid Voltage Condition

Abstract

In this paper proposes a control of three phase bidirectional current source converter with fuzzy controller is proposed to inject the balanced currents in different conditions. In this paper we are using the fuzzy controller compared to other controllers i.e. The fuzzy controller is the most suitable for the human decision-making mechanism, providing the operation of an electronic system with decisions of experts. In this topology, under a balanced grid voltage condition, the DC-link inductor current can be regulated over a wide range from zero to rated value while the AC-side current has low harmonic distortion. The AC-side currents will be unbalanced due to the presence of a negative sequence component. The FLC comprises of three parts: fuzzification, interference system and defuzzification. Various control loop structures for the operation of voltage source converter under unbalanced grid voltage conditions are reported in the literature. However, use of similar control loop structures for CSC may lead to unstable operation. Therefore, a control scheme to inject balanced three- phase currents into the AC grid under an unbalanced grid voltage condition is proposed in this paper. The stability of the proposed control scheme is studied using a small-signal model of the converter.