Abstract：The parameters of the stator winding capacitance to ground are the basis for the design of various earthing devices, and whether the earthing device meets the requirements needs to be verified through testing. For small-capacity generators with small capacitance currents, the grounding device parameters are designed by means of the centralized capacitance of the stator winding to ground, and almost no tests are carried out to verify this. For large and medium sized hydro generators, the capa- citance current is large and the measured concentrated capacitance has an error of more than 17% compared to the distributed equivalent capacitance, which may cause safety accidents due to improperly designed earthing device parameters if not verified through tests. The paper proposes test methods for four parameters: generator neutral asymmetric voltage, displacement voltage, single-phase grounding maximum capacitance current and single-phase grounding maximum fault current. Before and after the neutral point of the generator is connected to the grounding device, the parameter test of the generator neutral grounding system is carried out by simulating faults to determine whether the generator neutral grounding method and the parameters of the grounding device meet the engineering requirements. This has been verified on several large and medium-sized hydro generators and individual turbine generators, and the earthing devices designed with the test parameters of this test method are stable and reliable in operation.
江建明. 发电机接地系统参数试验方法现场应用[J]. 电气技术, 2023, 24(4): 63-68.
JIANG Jianming. Field application of test methods for generator grounding system parameters. Electrical Engineering, 2023, 24(4): 63-68.
2023, Vol. 24 
