The reductive effect of battery charger filters and supercapacitors against voltage spikes in auxiliary DC power systems

摘要

The DC power systems of power stations and substations provide the power supply for the key consumers of the auxiliaries, such as are the protection and automation systems that provide faults localization in primary circuits of the electrical installation. Nowadays the protection devices replacement process keeps going. Traditional electromechanical relays are replaced by the modern multifunctional intellectual electronic devices (IED). Such devices are the miniPC itself and require the power supply with the higher quality than electromechanical relays. Voltage surges, caused by the short-circuit inductance load commutation, like a high voltage breaker drive, could cause the IED restart and the protection outage for a particular period of time. To avoid such cases it is highly important to consider the requirements of the electromagnetic compatibility in terms of allowable voltage surges [1]. The problem of the extreme voltage surges can be solved by battery charger filters or EDLC introduction in DC power systems. Voltage surges damping is performed due to EDLC's or battery charger filters energy and it's dissipation to the short-circuit fault. The battery charger filters or EDLC introducing shows double effect - speeding-up the fuse tripping in faulted line and voltage surges damping.