PRODUCT DEVELOPMENT ASSOCIATES, INC. — Department of Defense SBIR Phase I: N171-075

Description

The Navys submarine fleet uses 3 phase delta power per MIL-STD-1399/300B. The power distribution system is driven from two power busses and automatically transfer loads between the busses when one loses power. During bus transfer, a 70 100 msec power interrupt may occur which can create upset in the loads. PDAs proposed rack mounted 40 kW Power Supply Bridge (PSB) is installed between the power distribution system and the loads to provide power to the loads during the interrupt period hence preventing upset in the loads. The PSB uses a novel Bidirectional Inverter circuit to convert DC energy stored in a capacitor bank to AC to power to the load when power is interrupted, and to efficiently charge the capacitors when power is normal. Precise Sensing & Control is included to direct the operation of the Bidirectional Inverter and the remainder of the PSB circuits in a manner that blocks backflow of current to the power distribution system during interrupt, or excessive inrush currents from the power distribution system at any time. The Bidirectional Inverter approach meets SBIR requirements and provides size, weight, efficiency, reliability, and cost characteristics superior to other alternatives.