A New Application of Transient Recorder to Magnetic Measurements (Part I: Core Loss Measurement at Very Low Frequencies)

A new method have been developed based upon analogue-to-digital conversion techniques and memories. The method involves the scaling of operating frequency from "real" to "optimum" for the power loss measurement. The advantages of using this techniques are as follows: (1) extreme availability at lower frequency region, (2) high accuracy and high stability, (3) simple measuring procedure, (4) digital indication. This method can be measured the power losses over the frequency range 0.1Hz to 1kHz for magnetic circuit and d.c. to 1kHz in such a purely resistive circuit. We estimate the accuracy of this core loss measuring system within 1.0% over all these frequency range. Using this system, specific core losses of the various grades of silicon iron have been measured in the frequency range 0.1Hz to 200Hz.