Abstract
Shunt Capacitor Banks play a vital role in improving power system capacity. They do so primarily through power factor corrections that increase voltage support to improve the overall system voltage profile. Shunt Capacitor Banks are the most economical devices to increase system capacity by reducing power loss. The economic benefit of Shunt Capacitor Banks is well appreciated because they are inexpensive to install and commission and they can be deployed at any point in the distribution system to enhance voltage profile.
Since Shunt Capacitor Banks are very important power system components, they need to be protected from faults that occur within the bank or anywhere else in the system that can affect them. Faults in Shunt Capacitor Banks must be monitored and an alarm or trip initiated to prevent a catastrophic event that follows a cascading failure of capacitor elements or units.
The protection method should trip the faulty unit and remove it from the system to save damage to the entire bank that could cause system instability. In Shunt Capacitor Bank protection, a recently developed solution that has grown in popularity identifies faulted phases or sections so a utility crew can pinpoint faulted location for speedy maintenance.The faulted phase or section identification solution for Shunt Capacitor Bank was introduced to power systems within the last decade but only limited to locating single-phase fault.
This research presents a multiphase multisection fault location identification for ungrounded double-wye capacitor banks with neutral voltage and neutral current protection. The proposed multiphase multisection fault location identification solution operates on the phase angle of neutral unbalance voltage or current. The unbalance phase angles of the currents and voltages at the neutral are already available from the protection method. The theoretical and mathematical derivations for the proposed solution will be presented and Real-Time Digital Simulator (RTDS) will be used to demonstrate and verify the solution.