Generator Neutral Grounding Resistor Cabinet

Baoding Ao Zhuo Electrical Equipment Manufacturing Co., Ltd. is a high-tech enterprise. The AZ-FNR generator neutral point grounding resistance cabinet it produces is a complete set of equipment for high-resistance grounding of 0.4kV to 24kV generator sets.

When a single-phase ground fault occurs during generator operation, if the fault current reaches a certain value, arcing grounding occurs at the fault point, creating specific "critical" conditions for the emergence of grounding overvoltage, leading to the generation of arc grounding overvoltage. Due to the weak voltage resistance of generators, their insulation is prone to damage. This can further expand the scope of stator winding insulation damage, even burn the iron core, and generate mechanical stress on the generator and its circuit higher than under normal conditions. If the fault is not detected and quickly eliminated in time, it may develop into an inter-phase or inter-turn short circuit. For these reasons, high-resistance grounding of the generator neutral point is widely adopted. When a single-phase ground fault occurs in its circuit, this method limits arc grounding overvoltage, reduces damage to the iron core, and decreases mechanical stress on the generator and its circuit.

Grounding the neutral point through resistance can limit the fault current to an appropriate value. On one hand, it provides sufficient sensitivity and selectivity for relay protection, while on the other hand, it ensures that only minor local damage occurs at the fault point. It limits the transient overvoltage to 2.6 times the normal line-to-neutral voltage, suppresses arc reignition, prevents arc gap overvoltage from damaging the main equipment, and also plays a significant role in preventing ferromagnetic resonance overvoltage.