An energy-fed three-phase four-wire power electronic load compatible with multiple load requirements

This paper proposes an energy-fed three-phase four-wire power electronic load that can achieve compatibility with single-phase, three-phase three-wire, and three-phase four-wire load simulation requirements. The main circuit uses an AC/DC/AC back-to-back structure, and the front stage is a three-phase four-bridge-arm rectifier, which is used to simulate different types of loads, while the back stage is a three-phase three-wire inverter, which achieves energy feedback. Firstly, comparing with the traditional three-phase three-wire power electronic load, each phase of the four-bridge-arm system is independent, and the input current of each phase can be tracked independently to its respective command current under the appropriate control method, so the system can simulate loads under a variety of operating conditions such as three-phase three-wire, three-phase four-wire, and single-phase. Then the three-phase four-wire power electronic load is compatible with the simulation of three-phase balanced, three-phase unbalanced and single-phase loads are analysed. Finally, a power electronic load simulation platform with a rated capacity of 200KVA is built in MATLAB/Simulink. The simulation structure verifies the effectiveness, feasibility and advancement of the power electronic load proposed in this paper.