摘要
大电网的发展及用户供电质量的提高要求智能变电站提供更加灵活、快速、可靠地保护。利用智能变电站信息共享的优势,提出了基于电流差动原理的集成保护新方案。该方案集成了变压器和母线为保护对象,根据其处于制动状态或者差动状态来实现故障定位;对集成保护方案的电流差动保护进行了改进,采用修正的差动电流补偿励磁电流的影响,不需要附加制动或闭锁技术,消除了内部故障时二次谐波制动导致的延时。利用PSCAD仿真软件构建了变电站仿真模型,对不同运行情况进行了全面仿真,验证了该方案的正确性。
Intelligent substations need to provide faster, more flexible and reliable protection to catch up with the development of the large power system and the improvement of the power supply for users. By taking advantages of information sharing between intelligent substations, we put forward a new scheme of integrated protection based on current differential protection principle. The scheme integrates the transformer and bus as the target of protection, and realizes the fault location according to whether the target is in the braking condition or the differential state. And we use the modified differential current compensate effect of excitation current to improve current differential protection of integrated protection. Thus, without additional brake or lock technology, we eliminate the delay caused by second harmonic restraint when internal fault occurs. Using PSCAD we build a typical simulation model to completely simulate different operating state, and finally prove the accuracy of this scheme.
出处
《东北电力大学学报》
2016年第6期25-29,共5页
Journal of Northeast Electric Power University
关键词
智能变电站
集成保护
电流差动保护
磁化电流
Intelligent substation
Integrated protection
Current differential protection
Magnetization curren
