LAUSR

With the rapid development of dc system, the residual current in dc system has become an urgent problem to be solved. However, the type B residual current devices (RCD) for ac systems could not be directly used in dc systems. In the dc system, the voltage fluctuation generated by the rectifier and the system circulating net currents generated by the line with different positive and negative parameters would interfere with the detection of RCD. In this paper, the residual current experimental platform was built firstly. Then the residual current detection prototype was developed and its operating characteristics were tested. The impedance model of human body was built for different electric shock conditions secondly. Thirdly, the influence of system factors on circulating net currents and the detection of residual current was analyzed. Finally, the configurations of RCD in dc system were proposed finally, protecting human body from electric shock and preventing electric fire accident threats.