Design And Application Of DC Insulation Monitoring System In Substation

DC power supply system is to ensure that all types of substation equipment, an important part of safe and stable operation, in addition to its sub-closing circuit breaker operation, signal equipment, protection equipment and emergency lighting and other equipment and facilities to provide power, but also in the station AC power loss Case, by the battery to provide adequate power to protect the normal operation of the above equipment.Therefore, the safe and reliable operation of DC power supply is essential for the safe and reliable operation of substations. However, due to the large number of DC power supply equipment and complex feeder cables, the DC power supply is often long, DC insulation grounding, AC into DC, Battery voltage abnormalities and other failures, and with the construction of a strong smart grid, the user demand for power supply reliability increased continuously, to improve substation DC power supply system operation and maintenance capacity is necessary.The type, principle and harm of DC ground faults are analyzed in the light of actual operation and typical cases of substation. Through analyzing the insulation failure of DC system, the DC insulation detection system is designed.The system includes insulation monitoring device, insulation line selection device, DC leakage current sensor, battery on-line monitoring device and AC channeling DC monitoring device to achieve the exchange of the DC system into the substation, insulation, grounding, DC mutual channeling, Battery ground and a series of fault detection, but also can achieve direct grounding of the DC line selection.Network communication for information transmission, and remote control software, remote control, remote real-time automatic control, collaborative interaction, constitute an integrated network monitoring system, the establishment of a safe DC system operating environment.Substation DC insulation monitoring system to achieve the battery internal resistance, DC insulation and grounding, battery intelligent discharge, AC into the DC on-line monitoring and DC system status assessment, fault warning.Battery performance comprehensive analysis to improve the battery failure to determine the accuracy of the battery failure to achieve early warning and the remaining capacity of the estimate;The system not only measures the battery voltage, internal resistance and other parameters, but also provides a switch volume acquisition and control output function, in order to achieve intelligent battery check the laying of the foundation;DC fault detection and positioning, to solve the DC ground fault monitoring and line selection problems; on-line real-time monitoring of DC bus AC component of the AC fleeing into the slip of the line selection, Timely elimination of exchange fleeing into failure.DC insulation monitoring system to realize the real-time monitoring of the running status and influencing factors of the various DC equipments in the substation, so that the DC system of the substation can be controlled and controlled to ensure the DC system of the substation is in good operation and safe and stable for the whole power network. Operation has laid a solid foundation.