| Abstract: |
| The Floating nuclear power plant grid is composed of power generation, in-station power supply and external
power delivery. To ensure the safety of the nuclear island, the in-station system adopts a special power supply
mode, while the external power supply needs to be adapted to different types of external systems. Because of
frequent single phase-ground faults and various fault forms, the fault line selection protection should be accurate,
sensitive and adaptive. This paper presents a fault line selection method in cooperation with multi-mode grounding
control. 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 can be
switched by the multi-mode grounding control. Based on the characteristic of HIFs, the fault line can be selected
by comparing phase differences of zero-sequence current mutation and fault phase voltage mutation before and
after the fault. Simulation results using MATLAB/Simulink show the effectiveness of the proposed method in solving
the protection problems. |
| Key words: Floating nuclear power plant, Multi-mode grounding control, Wavelet transform modulus maxima
(WTMM), Maximum united energy entropy ratio (MUEER), Phase difference, Single phase-ground fault |
| DOI：10.1186/s41601-020-00160-0 |
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| Fund: |
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