Experimental setup for inductive efficiency measurements of domestic induction systems based on energy balance

In an induction heating system the energy delivered into the work piece for heating purposes with respect to the self-heating of the windings is quantified by means of the induction efficiency. This parameter can be measured by using an energy balance, for example the ratio between the boiled water weight and the electrical energy supplied into the windings considering a period of time. In this paper an experimental setup for measurements of the induction efficiency in domestic systems is presented. In order to reduce errors in the electrical power measurements, which involve voltage and current signals at frequencies up to 100 kHz with harmonics, a method using differential measurements of the boiled water weight is proposed. Experimental results of the induction efficiency of a commercial induction system operated in real conditions are presented.