Power measuring in two-output resonant inverters for induction cooking appliances

In induction cookers efficiency and service quality are improved with an appropriate power control. In this paper three power measuring methods are presented and analysed. These methods are designed to measure power at medium/high frequencies (tens of kilohertzs). In the first method the general expression of power is applied. Others need a previous knowledge of application and exploit some characteristics of the power topology, in this case a two-output full-bridge series resonant inverter. The methods are compared in order to select an implementation for commercial induction cookers.