High Frequency Resonant Inverter System With Stacked Architecture and Merging Network

In this article, a high frequency resonant inverter system with stacked architecture and merging network is analyzed. The design method of multi-resonant circuit is given in detail. The parameter is designed by time domain analysis method which is more accurate than frequency domain method. Based on the single resonant circuit, a stacked topology is analyzed which can greatly reduce the switch voltage stress to almost around the input voltage. Meanwhile, the passive component can be merged to further reduce the number of inductor. Also the soft switching characteristics can be extended from rated resistive load to a range of resistive load by the merged passive network. The detailed operating principle and parameters design method are introduced. A 6.78 MHz experimental prototype is built to verify theoretical analysis and soft switching characteristics can be maintained between 25% to 100% load range and the peak efficiency can be 92.85%.