Implementation Technology of DC Current Step Standard Based on TMR Sensor

Abstract:
The study of transient step characteristics is very important for the transmission characteristics of DC transformers and the evaluation of the operation state of DC control and protection systems. Aiming at the problems existing in the step response test of the current transient standard in the transient closed-loop test technology, a realization technology of the DC current step standard based on the TMR sensor is proposed. And puts forward an implementation technology of DC current step standard based on TMR sensor. It used a Wheatstone bridge through the TMR sensor and output the voltage signal through the modulation circuit to realize the rapid step and accurate acquisition of current in the process of transient step, corrected the output current amplitude of TMR sensor by the steady-state transmission accuracy of the high precision resistor, then fitted the transient data of TMR sensor with the steady-state data of high precision resistance, which through the data fitting technology of AD conversion, output the complete standard data of the current transient step. Finally, the feasibility of the current step standard technology is verified by its application in the step response test of DC current transformer.