Study Of The Principle Of A Novel Sensor For DC Measurement Application

Heavy direct current (DC) measurement is a very important part of modern electric measurement. With more and more direct current power absorption, it is very urgent to develop the methods and instruments for heavy DC measurement to meet such requirement. This treatise is ground on the item of National Natural Science Fund "the research of multiplex Rogowski coils intelligent heavy DC sensors". According to our comprehension on the main principia of heavy DC measurement, we determine to study the theory of DC modulation comparator., for making a good foundation in theoretically and experimentally. After lucubrated the electrocircuit of magnetic core and the method of modulation comparator, we founded the simulation model of the magnetization curve and the modulation comparator under the environment of MATLAB SIMULINK to study the principle of magnetic modulation comparator. The model can exactly simulate the saturation of B-H curve of permalloy core. The model takes into account the influence of the self-resistance of stimulation winding, direct winding and measurement winding. The presented method can give great help to know the principle of magnetic modulation comparator, which also is important to design the comparator with satisfactory performance. On the other hand, According to the simulation result, we brought forward a new measurement scheme by comparing the difference of the output wave's virtual value from the detect coil. In order to validate the simulation model, we carry out a feasible experimentation. By analysing the result ,we arrive at a conclusion that the simulation model of the magnetization curve and the modulation comparator is accurate ,also the new method of DC measurement we brought forward is basically viable.