Study on Dynamic Characteristics of Single-Phase Grounding Fault of 1000 MW Hydro Generator under Different Grounding Modes

The continuous operation of 1000 MW large hydro generators in China is great value to the implementation “double carbon strategy” and power grid safety. However, with increase single unit capacity generator, problems fault grounding current neutral point voltage drift become more prominent, traditional analysis methods cannot accurately obtain dynamic data. Therefore, starting from mode taking a generator as research object, this paper establishes single-phase model under condition three-phase parameter asymmetry stator winding analyzes characteristics current, transient overvoltage, different modes by using method; influence frequency offset on are also obtained. Finally, according results, selection optimization method parameters proposed, which provides reference for protection strategy generator.