The Research Of The Pre-warning Of The Economic Risks In Power Svstem And Medium/Long-term Unit Commitment With Dynamic Cycling Costs

With the progressive development of power industry restructuring, the operation environment of a power grid company changes constantly, and more and more uncertain factors are involved. As a result, the economic risk associated with a power grid company increases. Given this background, it is of emergent importance to systematically investigate the economic risks encountered by a power grid company under different policy environments, build pre-warning and the management strategy for mitigating the economic risks. At the same time, as for the integration of variable renewable energy sources, the frequent cycling of thermal plant is a growing concern and an important problem which can’t be ignored for plant owners and system operators. The study of unit commitment with dynamic cycling costs is necessary to realize the purse of optimizing the dispatch economically subject to security constraints.Given the above background, this thesis is organized as follows:Chapter one summarizes the basic concepts of the economic risk associated with a power grid company and current situations of the studies of it, briefly introduces the assessment methods of risks. Chapter Two presents the main situations of the studies of the unit commitment problems, details the formulation of security constrained unit commitment (SCUC) with Benders decomposition method, so laying a good foundation for the following works. Chapter Three briefly introduces the basic applications of dynamic cycling costs. Chapter Four describes the economic risk pre-warning model, evaluation targets of risks and cordons for each and also describes the test system. Chapter Five details the formulation of the medium and long-term unit commitment with dynamic cycling costs and the results of the case study. Chapter Six summarizes the findings and new problems which are worth of studying.