Simultaneous power sharing and protection against faults for DGs in microgrid with different loads

Document Type : Research Paper


1 Department of electrical engineering, Songhor Branch, Islamic Azad university, Songhor, Iran

2 Department of electrical engineering, Kashan university, Kashan, Iran

3 Department of electrical engineering, Kermanshah university of technology, Kermanshah, Iran


The LVRT (Low Voltage Ride Through) is the main characteristic of every power system in faulty conditions. When fault occurs, it is essential for power system such as microgrid to control the voltage and frequency normally. Naturally in fault status, the unbalanced voltage and current are inevitable, but with the aid of LVRT technique, microgrid can keep stability in main system parameters such as voltage and current of each phase. In this paper, the microgrid is proposed in islanded state and using the reactive power injection in faulty conditions, and the LVRT technique is applied. When reactive power is inserted, simultaneously the active power must be reduced, and so the current is limited, and overcurrent is controlled. Simulation results indicate that this strategy enhances the presentation of the structure in symmetric and asymmetric faults. That is noticeable declaring that the suggested approach has not degraded the power sharing among DGs both in faulty and faultless status and also plug and play property is kept using this suggested LVRT strategy.


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