Modeling and assessment of energy management challenges for distributed wind farms

Abstract

The advent of deregulation of electricity to meet the increasing load demands and the call for more efficient sustainable energy practices have dominantly amplified the need for incorporation of renewable energy systems in today’s power networks. Wind energy systems can be a leading source of renewable energy with adequate exploration into the uncertainty surrounding its dependency on climatic changes. The aim of the thesis is to analyze the potential of energy savings through the inclusion of wind energy in the already existing network. Wind, in conjunction with the conventional power generators, needs to meet the continuously varying load demand while considering the technical real-time constraints imposed by the system. The output from conventional generators is deterministic while in the case of wind, due to its stochastic nature, the output is intermittent. This is modeled by Weibull probability distribution function due to its discontinuous behavior. The first step involved in planning and operating the power system with a wind farm, is providing a load flow solution. Among various techniques, Newton-Raphson is one of the most widely used methods to calculate the total generation and line losses involved in transmission. The next step is to use the load flow solution to optimize the economic dispatch of the real power in the system. The optimal allocation of the generated power among conventional and wind units are based on the operating cost of the units and the cost of wind power. The cost of wind units accounts for various scenarios such as the penalty cost due to overestimation and underestimation of wind power and the direct cost pertaining to the issue of ownership of the wind generators. The research involved in this thesis provides a novel model for power system operation combining conventional and renewable energy along with remote energy storage systems, which are validated effectively for the proposed system. Furthermore, with the help of the Newton-Raphson load flow technique followed by economic dispatch, an efficient and economical solution is provided to determine the optimal output at the lowest cost while keeping the transmission and other operational constraints in check.