The invention discloses an ocean
nuclear power platform
power grid grounding fault line selection protection method and an ocean
nuclear power platform
power grid grounding fault line selection
protection system, belonging to the field of ocean
nuclear power platform
power grid protection. The ocean nuclear power platform power grid grounding fault line selection protection method comprises the following steps of: when a single-phase earth fault occurs in the
system, if a fault
current amplitude is higher than a given threshold, keeping a neutral point in a high-resistance grounding mode, selecting an optimal
wavelet basis and a
decomposition scale based on a maximum energy joint entropy ratio, and performing earth fault line selection by utilizing a
wavelet transformation method based ona modulus maximum value; when a high-transition resistance grounding fault occurs in the
system, switching the neutral point to a small-resistance grounding mode, and constructing a
branch zero-sequence current and fault phase
voltage break variable phase comparison line selection protection method based on features of the high-resistance grounding fault to perform grounding fault line selection.The ocean nuclear power platform power grid grounding fault line selection protection method can be effectively matched with the
operation mode and the grounding fault features of an ocean nuclear power platform power
system, is high in line selection accuracy rate, is suitable for various grounding fault
modes possibly happening to the platform system, and effectively improves the safety defensecapacity of the ocean nuclear power platform.