Protection and Control of Modern Power Systems

The floating nuclear power plant is a moving nuclear power station at sea, it is the combination of marine engineering and nuclear engineering. It can provide safe and effective energy supply for remote islands, offshore oil exploitation and seawater desalination etc. Since it is compact in structure, and the ship hull is directly used as the ground loop, it is prone to generating different fault forms. Thus, the fault line selection protection should be accurate, sensitive and adaptive. In order to give consideration to the operation safety and the protection sensitivity in case of various ground faults, a fault line selection method in cooperation with multi-mode grounding control is presented. Based on the maximum united energy entropy ratio (MUEER), the optimal wavelet basis function and decomposition scale are adaptively chosen, while the fault line is selected by wavelet transform modulus maxima (WTMM). For high-impedance faults (HIFs), to enlarge the fault feature, the system grounding mode is switched by multi-mode grounding control, and the fault line is selected by comparing phase differences of zero-sequence current mutation and fault phase voltage mutation before and after the fault. Simulation results show the effectiveness of the proposed method in solving the protection problems. Read more.