Document Type : Original Research Paper


1 Faculty of Electrical and Robotics, Shahroud University of Technology, Semnan, Iran

2 Department of Electricity and Power, Shahroud University of Technology, Semnan, Iran


Embedded generation is a developed generation form in modern power systems. Many of embedded generators are working in parallel with the modern power networks. On the other hand, the power systems are designed based on centralized generation, not to work with embedded generators. Therefore, the embedded generators may be lead to some control and protection problems in these systems. The embedded generator protection against loss of main network (LOM) is one of the most important of these problems. A practical protection procedure must be able to recognize the differences between the LOM and similar conditions such as load switching, ordinary faults, etc. In this paper, a new method based on synchronous generator sequence Impedances was developed that has an improved performance. The MATLAB/SIMULINK based system simulation shows the validity of the proposed method.


Main Subjects

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