Research And The Countermeasures To The Problems Of Substation DC System

According the2011-2012defect analysis report of Foshan Power supply bureau thesecond substation management, the defects of DC system equipment accounted for a largeproportion in secondary equipment, the main defects include: insulation reduced (groundingfault, loop fault), battery failure, the charging module failure. Since the DC system is mainlyfor the control circuit, signal circuit, relay automatic device, circuit breakers, etc. to providereliable and stable of uninterrupted power supply, the frequently happen of defects of DCsystem pose a great threat to the safe and stable operation of power grid.Based the actual running situation of the DC system equipment in Foshan Power SupplyBureau the second substation management, carry out the following researches, and putforward the corresponding countermeasures:(1)For the DC system grounding fault, analyze the cause of the DC system groundingand the resulting harm, sum up the dc system grounding screening method, and applies to500kV cang jiang substation and other important substation grounding troubleshooting, withremarkable results.(2)For the DC system loop fault, analyze the cause of the DC system loop fault and theresulting harm, put forward to solve the loop fault, develop online DC power supply loopalarm installations and electric circuits for equipment.(3)For the DC system battery failure, analyze the relationship between battery capacityand the resistance, battery online monitoring automation and its realization are put forward.Finally, standardized management of substation DC system work is put forward, andseven aspects has carried on the detailed elaboration, such as the status evaluation and therisk assessment of DC power supply device, accounting Substation DC power supplies, DCload distribution, draw DC feeder network and differential configuration diagram, the DCpower supply device parameter settings, periodic examination of the DC power supply, DCpower equipment acceptance. Through the implementation of the standardization work, thesecurity personnel further clear the substation secondary circuit DC power supply, to helpquickly find the defects of DC power supplies, in order to avoid accidents. Meanwhile, the working content and working behavior of DC power supply equipment effectivelyspecification the DC power supplies work content and work regulate behavior, effectivelyraise the level of DC power supplies management, and ensure safe and stable operation of DCpower supply.