Distribution Network With Distributed Power Protection Relay

As tension of conventional energy sources and increasingly serious environmental problems, more and more attentions are given to the development and utilization of renewable energy and combined heat and power (CHP) technologies. Also, because some of the inherent shortcomings of the large power system, the diversity of users and the increasing power demand high reliability requirements, making the unique advantages of distributed generation has been rapid development. As the number and capacity of the distributed generation increasing, the protection system of distribution network is affected, security and stability of the system being tremendous challenged. In this context, in-depth analysis of the impact of distributed generation on protection of distribution network, proposing the corresponding protection scheme and the corresponding strategy to reduce their impact on system protection and rapid removal of faults, to improve the utilization of distributed power and reduce the power loss that is important theoretical significance and application value.Firstly, the basic concept of distributed power generation and distribution network the basic principles of protection are introduced and analyzed. Then, the impact of distributed generation on protection of distribution network is analyzed, particularly it analyzes the impact of current protection and automatic reclosing to the system. It is focus on the impact of the one or more distributed generation brings to current protection of distribution network, and propose corresponding countermeasures; At the same time, according to the impact of automatic reclosing, it propose the protection programs to avoid failed reclosing.According to research of the impact of the capacity of distributed generation brings to distribution network, it discusses the problems of distributed generation basing on the coordination and reliability of the relay protection. Basing on the principle of short-circuit distribution mechanism, it proposes the best access locations and the best program of the order of several distributed generation.By using the electromagnetic transient simulation software PSCAD/EMTDC to build the model of distribution network and simulation, the simulation data processing by MATLAB to verify the theoretical results and the corresponding scheme is correct.Finally, the paper summarizes the research work and discusses the future research directions of next step work.