Integration of renewable energy sources in power system has increased rapidly in recent years due to environmental effects such as climate change and global warming. Renewable sources provide clean and sustainable energy but it has some negative effects on power system. Renewable sources are mostly inertia-less sources and they increase instability in system. Frequency deviations are main indicator of their fluctuation because of their variable energy nature. To stabilize frequency, spinning reserves are there. Most of generators providing spinning reserves are fossil fuel generators, their operation is costly and not environment friendly. To minimize dependence on spinning reserves, demand side response is a method, which can provide frequency reserves cheaply and have a fast response. Demand side response is to shift loads of end users from peak hours to off-peak hours in response to frequency deviations or any contingency in power system with agreement with end users. This paper proposes the use of demand response through load management. Direct control method is used to control loads of end users. In response to frequency deviations, loads are ON/OFF to stabilize the frequency. For that purpose, a simple microgrid is designed in MATLAB/SIMULINK comprises of Solar PV and diesel generation sources. Loads are controlled through simple controller, which monitor frequency and act accordingly. Different scenarios are simulated, with demand side response and without demand side response. The results showed that with demand side response, frequency can be stabilizing quickly and system can be prevented from instability.
Syed Afzal Shah Zafar Ahmad Israr Uddin and Muhammad Nazeer Active Power Control In Modern Power System Through Demand Side Response International Journal of Engineering Works Vol. 6 Issue 12 PP. 521-524 December 2019
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