Evaluation on chamber volume and performance for simple calorimetric power loss measurement by two chambers

In this paper, a calorimetric power loss measurement (CPLM) which is low cost and a simple structure using two cheap chambers. A feature of the proposed method is that the power loss of the power converter is measured from the transient state of the rise in temperature. As a result, the measurement time of the power loss using heat conduction equation formulas is reduced by 86.1% compared with a conventional method which uses the steady state of the temperature due to the power loss. In addition, another method that can reduce the measurement time is discussed. In particular, the temperature in one of two chambers is controlled to follow the temperature in another chamber for the transient stat of the rise in temperature. As a result, the measurement time of the power loss is reduced by 87.5% in compared with the conventional method. In order to confirm the validity of the proposed method for actual applications, a switching power supply is used for an objective of the power loss measurement. Moreover, the relationship among the measurement error rate, the measurement time and the chamber volume. As a result, all of the maximum errors of the measured power loss were within 10%.