A Three-Phase Adjustable-Voltage-Ratio Transformer Based on Magnetic Flux Valves

This paper presents a new three-phase adjustable-voltage-ratio (AVR) transformer. The AVR transformer uses a new voltage-controlled magnetic device called the magnetic flux valve (MFV) to control the magnetic flux through the core of the transformer. In this way, the amplitude of the three-phase output voltages can be adjusted continuously with the range designed when the amplitude of the three-phase input voltages and turn ratio of the transformer are fixed. The configuration and working principle of the proposed three-phase AVR transformer are introduced. A prototype is designed and constructed. Experimental results on the prototype are provided to validate the AVR concept of the transformer.