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The universal power demand is increasing every day because of population growth, industrial revolution and high standards of living. The renewable energy technologies (RETs) are environmental and cost‐effective solutions to satisfy dynamic load profile based on the application of multiple components of a standalone microgrid system that encompasses photovoltaic (PV), diesel generator (DG), electric storage system and wind turbine generator (WTG). This study reveals more insight into various research questions that have not been completely addressed in past investigations. The contributions of the study are expressed: (i) analyse the effects of RETs on the total cost, (ii) test the total benefits, (iii) estimate the market benefit share of the unit that reflects the benefit of one generation unit in proportion to the whole power system, (iv) maximise and minimise the yearly average power generated by (PV and WTG) and DG. This research work presents the application of fmincon optimising tool to accomplish the objectives of the study owing to some significant characteristics. The outcomes of the work show the validity of the model and can assist the utilities to minimise the costs that are identified with the optimal operation of their power systems. [ABSTRACT FROM AUTHOR]

Summary: The addition of photovoltaic (PV)‐based distributed generators introduces several challenges to power system protection and control engineers. In a multi‐source distribution network, power flow becomes bi‐directional, and conventional overcurrent and earth fault protection schemes are threatened. Addition of PV‐based distributed generation could lead to protection blinding, sympathetic tripping, and loss of coordination in conventional overcurrent protection. This paper evaluates the general concerns regarding protection in a PV‐based distributed generation network, by modeling a power system with sequence networks for different types of faults. The power system is simulated with Digsilent PowerFactory. The results show that many of the general concerns can be mitigated by using sequence components to identify faults. A method is presented to adapt conventional overcurrent protection schemes without the need for communication‐assisted protection. [ABSTRACT FROM AUTHOR]

This review paper is focused on common protection challenges related to the integration of distributed generation (DG) into medium voltage (MV) distribution power systems. Protection challenges, as indicated by the general scientific community, are explained and discussed. Based on these challenges, several alternative centralized and decentralized protection alternatives are explained and critically evaluated. Photovoltaic (PV) based distributed generators are connected to the utility grid through inverters, which are able to control active and reactive parts of their output and also limit their fault current contribution. Research is proposed to quantify the risks to protection in conventional power systems with increasing presence of distributed generation. Since the positive, negative and zero sequence current output from PV inverters can be controlled, conventional overcurrent protection using negative and zero sequence current is proposed to increase the protection reliability and maintain coordination in the presence of distributed generators. [ABSTRACT FROM AUTHOR]