Monitoring Power Quality in Small Scale Renewable Energy Sources Supplying Distribution Systems

The integration of renewable sources within the existing power system affects its traditional principles of operation. The renewable energy sources (RES) can be used in small, decentral‐ ized power plants or in large ones, they can be built in small capacities and can be used in different locations [1]. In isolated areas where the cost of the extension of the power systems (from utilities point of view) or the cost for interconnection with the grid (from customer’s point of view) are very high with respect to the cost of the RES system, these renewable sources are suitable. The RES systems are appropriate for a large series of applications, such as standalone systems for isolated buildings or large interconnected networks. The modularity of these systems makes possible the extension in the case of a load growth.