The Study Of The Uncertain Factors In The Power Networks Planning

This paper proposes several novel and applied methods for Power Networks Planning from four aspects in dealing with uncertain factors. The first aspect applies the fuzzy set theory, gray system principle and unascertained number to improve the original load forecasting models; the second aspect applies the fuzzy synthetic evaluation and evidential theory to solve the problem of the uncertain factors ,when choosing the address of the transformer substation; the third aspect introduces the concept of the net present value and the fuzzy set theory, and proposes the a model for the evaluation of the power network planning.; the last aspect presents some new theory to judge rationality of the scheme of the network planning.The significance of the research is given, according to the characters of the uncertain factors. This paper sets forth the feasibility and the advantage of the fuzzy set theory, gray system principal, evidential theory and unascertained number in the aspect of solving the problem of the uncertain factors.Because of the influence of the uncertain factors to the long-term and medium-term load forecasting, this paper applies some new methods to improve the original models, and presents some new models. The examples tell that these models are more applicable for the long-term and medium-term load forecasting.The paper introduces the net present value to evaluate the scheme of the power network planning. Considering the existence of the uncertain factors, the paper introduces the sensitive analysis method to analyze the uncertain factors. The example tells that these methods can solve the problem of the uncertain factors.In order to solve the influence of the uncertain factors to the judgment of the scheme of the network planning, the paper introduces the evidential theory and the fuzzy synthetic evaluation method. The example tells that the methods are applicable for solving these kinds of problems.