Grid-connected Wind Power Modeling And The Evaluation Of Capacity Credit

With scientific and technological progress and economic development, people’s demands for electric power supply expand increasingly. At the same time, shortage of conventional source of energy and deterioration of greenhouse effect are caused. Thus, the great mass fervor that new energy power generation technology is developed and used energetically in the whole world appears. As a result, wind energy becomes a type of energy that has been developed early. Because wind energy is featured by intermittent nature and randomness, we cannot simply use installed capacity to express contribution of wind electricity to electricity generation in the electrical power system. Therefore, discussions about effectiveness of wind power generation uses credible capacity as a yard stick. In this process, reliability analysis is an important component of credible capacity calculation. As wind power integration is a link that goes through the whole process of this research, mathematical, it is necessary to build its mechanical and electrical models successively and make an appropriate balance in the aspects of operating rate and accuracy in order that following researches can be finished.First of all, this thesis introduces some basic models about wind pov/er generation, such as wind speed model, air kinetic model of wind turbine, electromechanical model inside units, wake effect model in a wind power plant and the unit outage model that can be applied to reliability analysis to give a theoretical basis for the following content. Secondly, it centers on an overall aggregation model of the wind power plant, introduces the theory of loss apportionment from tide tracing field, and puts forward the method that inner loss in the aggregation model can be distributed to each unit accurately by the principle of loss distribution. In doing so, an equivalent impedance model which is more convincing can be obtained. At the same time, it has proposed a computing method of cascade models for the first time. In addition, it uses simulink software that is sensitive to aggregation errors to implement simulation, and observes and compares simulations of a single unit aggregation model and a parallel aggregation model in order that more selectable schemes for simulation about large-scale integration of the wind power plant and the modeling field can be provided and people can find optimum models for researches in future. Later, it introduces common ways to compute reliability and credible capacity of wind electricity, gives a brief introduction to sequential and non-sequential Monte Carlo simulation methods, applies the aggregation theory to reliability analysis and puts forward selection modes about probabilistic contribution of aggregation units. Finally, by MATLAB programming, it carried out wind power integration for IEEE RTS24node standard model and calculates reliability of the aggregation process, and figures out credible capacity by equivalent conversion to compare credible capacity under different conditions. It is this thesis that has applied the theory of loss apportionment to the modeling field of wind power plants and put forward the theory about cascade models that can be used at an experimental stage for the first time. In addition, it applies the aggregation theory which uses wake effect as a partition standard to the field of reliability analysis. Undoubtedly, this thesis provides theoretical reference for future researches.