The Development of a Lightweight, Modular, Sinewave Inverter System Eliminating Common Control and Low Frequency Transformation

The British Post Office (BPO) and ERA Technology Ltd have developed a new concept in modular inverter systems by combining expertise from an earlier development with inverters to a novel ERA design. Modules can be paralleled to suit different loads, and reliability can be increased by the further addition of active redundant modules. The new inverters produce a high efficiency 50 Hz sinewave output without the use of iron-cored components. The modules do not require a master control for synchronisation and also incorporate a facility to switch the load between the inverter output and an alternative a.c. supply.