Neutral Point Treatment in Three-Phase Networks
Ismail Kasikci · 2017
The short-circuit currents are determined by the voltage sources present in the network and by the network impedances. The requirement of an optimum and inexpensive network can lead to different neutral point treatments. The main faults are the single-phase short circuit and the short circuit to ground. If the short-circuit currents are identical in all three conductors with a three-phase short circuit, then the fault is symmetrical. The short-circuit currents are determined by the voltage sources present in the network (generators and motors) and by the network impedances. The requirement of an optimum and inexpensive network can lead to different neutral point treatments. This chapter briefly discuss the principles of grounding systems and then deal with the different methods of neutral point grounding in high-voltage networks. The ground potential rises and touch voltages of a grounding system can be calculated from known data. The fault current frequently divides in the system.