Power quality is a growing concern on electric power systems. Customers are requiring a higher quality of service as a result of more sensitive electronic and computer-controlled loads. Capacitor switching events and voltage sags associated with remote faults that never caused problems in the past now cause equipment tripping and even failures within customer facilities. Also, customer loads are generating increasing amounts of harmonic currents that can be magnified on the distribution system due to resonance conditions. This paper presents an overview of three important power quality concerns: harmonics; transients; and voltage sags.

This paper describes capacitor bank design, transient studies, protective relaying considerations, and operating experience. Associated with an application of high voltage capacitor banks. A 500 kV capacitor application and a 230 kV fuseless capacitor bank are presented as examples of developments in the design and protection of shunt capacitor banks. In addition, this paper presents the most significant findings of a large transient study completed to evaluate the impact of the 500 kV application. Operation experience is presented for a 500 kV zero voltage closing relay in combination with a preinsertion resistor used for transient suppression during closing. Analysis of a restrike failure of a 500 kV arrester is discussed along with field testing of a fuseless capacitor bank

This paper describes a concern for nuisance tripping of adjustable-speed drives caused by capacitor switching on the utility distribution system. The characteristics of the drive system, the customer electrical system, and the utility distribution system that affect this phenomena are analyzed using sensitivity analysis simulations. Possible solutions to the nuisance tripping problem are also presented.