Power Loss Evaluation of 2.5 MHz High Frequency Inverter Based on Frequency Multiplying Method

Inhalt:
This paper describes a 2.5 MHz high frequency inverter based on a frequency multiplying method. A proposed circuit consists of a five-phase inverter and multi-core transformers. An operation frequency of the five-phase inverter and multi-core transformer is 500 kHz which is one-fifth of an output frequency of 2.5 MHz. Therefore, the proposed circuit can realize high efficiency by utilizing available semiconductor switches and magnetic materials. In this work, a principle of suppression of iron loss is experimentally clarified by measuring B-H curves of a single transformer without a load when sinusoidal voltage is applied. Next, power losses of semiconductor switch and multi-core transformer are formulated. Finally, a power loss distribution is clarified based on theoretical analysis and the measured efficiency of the prototype circuit.