分布式发电智能电网的充分式保护原理与方法

分布式发电技术在智能电网中被广泛应用。针对采用分布式发电技术的智能电网保护安全性问题,提出充分式保护原理。新原理与传统保护原理的最大区别在于并不针对同一类故障的所有可能发生形式,而是只针对那些在绝大多数情况下更可能发生的故障形式,提取具有充分代表性的故障特征,并以此为保护方案着力点。传统保护方案对全部理论上即可能发生的故障要求同等的选择性,因此作用前提要求较高,往往表现在过分强调通信及同步环境,多数情况下甚至难以应用。而充分式保护原理则针对实际运行中更容易发生的普遍性故障,首先解决,要求更低,实用性更强。针对分布式发电技术的网络分析了大多数线路故障下均反映出的线路电流幅值特征,在此基础上提出了基于充分式原理的保护方案。仿真证明新方案更适应分布式发电智能电网的保护环境,相比传统保护原理要求更低但可靠性更高。

Sufficient criterion protection theory and method for distributed generating smart grid

Distributed generating technology has been widely used in smart grid. A new sufficient criterion protection strategy is proposed to solve the protection problems in distributed generating smart grid. The largest difference between sufficient criterion protection and traditional ones is that it is based on the selected representative fault characteristic which is widely seen in almost every actual fault condition, yet not lay equal strength on those theoretically might happen but hardly seen ones. Traditional protection theory emphases selectivity on any theoretically fault, thus requires rigid prerequisite, such as the communication and synchronization requirements. On contrast, the new sufficient criterion protection is more practicable. In this paper, a sufficient criterion of fault current amplitude characteristic is analyzed, and then a new protection method is proposed based on this sufficient criterion. Simulation shows the new strategy is more adaptable in distributed generating smart grid, and more reliable than traditional protection strategy.