Design of High Power Regenerative Battery Discharger System for Nuclear Power Plant

Abstract

In a Nuclear Power reactor, safety loads are backed by standby battery system. The healthiness of the battery is very essential requirement and prominent attention is given to availability and reliability of battery supply in nuclear plants. Hence regular monitoring and testing the performance of the battery is a prime requirement. The capacity and load cycle discharge testing of the battery is done annually and the current system employed is to discharge the battery current through resistor banks, which results in unusable power consumption and is uneconomical. The growing trend in power electronics field has given the new technology of regenerating the dissipated power to grid. This paper proposes a high power electronic regenerative technology with high efficiency, low harmonics to pump the dc power to the grid. Though, it is available at lower rating in industry, the paper proposes a high power regenerative discharge system. The topology selected is interleaved boost converter interfaced to a three phase grid connected inverter. The challenges involved are high power operation, steep current discharges with a minimal interference to the normal plant operation power supplies during the regeneration. This paper also presents the system design and simulation results.