Design and testing of a 5 MW battery-based inductive power supply

A 5 MW battery-based inductive power supply (IFS) was designed and tested. The battery consisted of 636 low-resistance, sealed, lead-acid batteries organized in strings that are connected to busbars via small-size contactors. A vacuum breaker serves as a closing switch, while an explosively driven opening switch interrupts the circuit, transferring the coil current to the load. In case of load malfunction, the energy stored in the coil is dumped into a dissipative load. The systems for control and measurement are decoupled from the high-current carrying conductors. In this paper, optimization of the battery-coil matching is discussed. The current sharing between the strings is analyzed. IFS parasitic inductance for different arrangements was calculated and reduced by careful design to 4 μH. PSpice simulations of the IFS accounting for nonlinearity in the components are presented. Main components, such as batteries, contactors, and protective equipment were tested under high current conditions. The IFS was evaluated both with a resistive and an electro-thermal load with stored energy up to 0.5 MJ. Power amplification of 100 was obtained. It was found that the experimental results agree closely with calculations, and the IFS performs according to the design specifications. Methods of developing a more compact IFS using advanced battery technology are analyzed