Microgrids: modelling and control

Abstract

The global warming and other environmental hazards of conventional sources of electrical energy push the energy sector continuously towards distributed energy resources (DERs), especially renewable sources [1]. The fluctuating power produced by renewable sources such as wind and solar photovoltaic (PV) systems may bring challenges in generation/load power balance. With increasing penetration of renewable energy, the function of such distributed generation (DG) is changing from an auxiliary role to a primary role in the energy sector. DERs, renewable or non-renewable, and energy storage systems (ESSs) are integrated into what is known as a microgrid (MG). An MG deals mainly with the issues associated with the integration of such intermittent renewable energy sources (RES s) and ESSs. It gives many advantages not only for power balance but also for environmental challenges, economic benefits and grid reliability requirements [2]. Moreover, MG handles many technical issues in decentralized form [3,4]. There are intensive interests to develop and study the future horizon of MG concept throughout the world [4]. Generally, MG is a small -size, discrete electricity framework consisting of a collection of DG units and loads. It may operate in grid -connected or islanded mode and provide seamless transition between the two modes. MG may also include conventional generators such as diesel -based synchronous generators to mitigate the effects of the intermittency nature of RESs. Furthermore, many RESs act as inverter -based sources as inverters are used to interface them with the host grid or AC loads.