Guodian Nanzi RP-1 Rotor Protection Device

Rotor Single-Point Grounding Protection
Depending on the field wiring method of the rotor winding, either a dual-end injection or single-end injection rotor grounding protection principle can be selected. The injection power supply is applied between the positive and negative ends (or negative end) of the rotor winding and the shaft. The switching cycle of the injection power supply can be adjusted based on the capacitance of the sub-winding to ground, enabling real-time calculation of the rotor single-point grounding resistance. The protection responds to the decline in insulation resistance between the generator rotor and the shaft. The working circuits for dual-end injection and single-end injection rotor grounding protection are shown in Figure 1 and Figure 2, where Rx is the measurement loop resistance, Ry is the high-power injection resistance, US is the injection power supply module, and Rg is the insulation resistance between the rotor winding and the shaft.