Renewable Energy Source Based Microgrid: Control and Dynamics
Sangeeta Modi PESU EEE2020, Lecture Notes in Electrical Engineering
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Abstract
The major challenge for world's power sector is varying load, low energy efficiency, environmental issues, and low power quality. Microgrid, a smart grid key technology, offers a promising solution to these issues to some extent. By using the renewable energy sources, the generation efficiency can be increased up to 90% without any loss for transmission. This paper presents the performance analysis of a hybrid microgrid under islanded mode. Microgrid under consideration consists of an array of 33 parallel strings of 5 modules connected in series, and maximum power delivered with this combination is 50 KW at 1000 W/m 2 irradiance, and wind turbine of nominal output power of 50 KW at wind speed 12 m/s, a battery of 500 V, 40 Ah rating, an AC load of rating 150 KW, 50 KVAR and a DC load of 200 kW have been considered for the microgrid. Utility grid of three-phase, 25 kV, 50 Hz is connected via three-phase two-winding Star-Delta transformer of 100 kVA, 25 kV/260 V, 50 Hz. In this paper, decoupling PQ control method turns to voltage/frequency (V/f) control for islanded mode of operation. With distributed generation sources supplying loads, a proper load sharing is the objective without overloading the system. Maximum power point tracking (MPPT) controller based on incremental conductance algorithm has been employed.
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