Isolating DC Grounds in Modern Power Plants

摘要

Most hydro project owners have converted from relay logic and/or pneumatic control and protection systems to microprocessor-based systems. However, many have retained a significant portion of the old DC control systems, specifically the devices controlled by discrete output relays in the new systems to allow safe shutdowns of equipment from the stored energy in station batteries. These systems generally provide uninterruptible power to emergency lube oil pumps, auxiliary power system draw-out breakers, and generator and line breakers.