Sampling Test and Comparative Analysis of Insulation Monitoring Device in DC Power System for Station

The insulation monitoring device is an important equipment in the station power supply system, which monitors the insulation of DC circuit in real time during operation. In order to fully grasp the performance of the insulation monitoring device of the DC power supply system in the substation, this paper carries out spot check test on 16 typical products of ten companies, and makes a comparative analysis. The test results show that the basic function of insulation monitoring and the function of grounding line selection of each product meet the requirements. However, the functions of the old models are not complete, and there are basically no AC and DC voltage intrusion alarm, voltage balance, ground capacitance detection and other practical functions, which affect the reliable operation of the station DC power system. It should be updated and reformed in time. By comparison, the new model products have more functions and the overall performance is obviously better than the old model products. The test products of different companies have their own characteristics and shortcomings. It is suggested to further improve the performance of the products to provide reliable equipment support for the station power system.