دانلود رایگان مقاله انگلیسی اثر مولد توزیع شده در محافظت از سیستم های قدرت - IEEE 2017

Abstract

Day by day demand of Electricity is increasing so, in order to fulfill this demand we need to increase generation of power. Because of this increasing demand, nonrenewable energy sources are on the verge of extinction so the solution is to use renewable energy sources. One such solution is to connect DG having renewable energy sources in power system. But the insertion of DG has some impact on a power system. This paper deals with the evaluation of the impact of DG on the protection of power system. The work presented in this paper consists of a simulation of a radial power system in PSCAD /EMTDC software. Monitoring of both fault current and the load current is done in the simulation. The impact of DG on fault current under the influence of LG, LL and LLLG fault with and without protection is studied. Maximum magnitude of fault current is found in case of LLLG fault. Also, the impact of resistive fault current limiter on the magnitude of fault current is studied. Both DG and source is protected from fault current by using overcorrect protection with pick up value of 2kA and 4kA respectively.

VIII. CONCLUSION

The presence of Distributed Generation may cause higher fault currents that are over the breaking capacity of circuit breakers. Therefore, existing protection devices are exposed to more electrical stress than normal. The cases presented in this paper shows that by adding DG the current drawn by the induction motor is contributed by both source and DG. Also, the DG contributes to the fault so it is found that magnitude of fault current increases with the insertion of DG. By providing instantaneous overcurrent protection both source and DG are protected. The presence of DG increases fault current levels and lead to protection problems. For solving these problems a solid state FCL is proposed to connect in series with DG. The main advantages of the proposed FCL are simplicity in structure and control, fast response. Also, this type of FCL has no effect on utility voltage and current at normal system operation.