Energy Storage System Control Strategy for Restraining Overvoltage Caused by Switching Non-Load Power Transmission Lines

Abstract

During the switching operation of the non-load power transmission lines, the undisired switching overvoltage issue is inevitable, causing grid voltage oscillations, waveform distortion and other phenomena at the end of the non-load power transmission lines, and even lead to the insulation breakdown, all above phenomena probably make the power transmission failure. To avoid the above harmful cases, the formation mechanism of the undisired switching overvoltage issue caused by switching non-load power transmission lines is first analyzed in detail. Based on this mechanism analysis, the energy storage system (ESS) based overvoltage suppression method and corresponding ESS voltage command synthesis algorithm are developed. The method can quickly and effectively restrain the voltage change rate and reduce the voltage difference between the initial value and the steady state value of the power transmission lines, so that the line voltage during the switching operation can be kept within the safety limit range. Finally, a simulation model was built by using MATLAB/Simulink software, and the simulation results verified the effectiveness of the proposed overvoltage suppression strategy.