Evaluation Of Power System Security In Electricity Markets

In electricity market, the dispersed and separated management has replaced the centralized management. In each part of power system, economics have became the first consider factor. These changes increase the possibility of some uncertain affairs and bring tremendous influence to security and reliability of power system.The traditional power system security analytical method is research each point in parameter space of system, but it can't bring enough information of whole system's security. Security region method can conquer this disadvantage and bring the whole information of system to the controllers. In this paper, we study the use of the security region to research the applied power steady-state security region with fuzzy loads and the optimal preventive control based on voltage security in electricity markets.1 Research several modes of electricity market especially the pricing of security.2 Proposes a mathematical model and algorithm for the computation of applied active power steady-state security region (SSR) with fuzzy loads in electricity market. The object function of the model is minimization total payments of energy in the spot balance market. The model utilizes the concept of fuzzy confidence intervals to calculate SSR under various fuzzy confidence levels.3 Proposes the model of optimal preventive control based on voltage security in electricity markets. The objective function is the minimization of total payments of preventive control and must ensure each bus have enough voltage security margin. This paper also introduces the sensitive index of voltage security based on L index and the concept of equivalent reactive power compensation of generator. Given the pricing of each reactive power compensation based on their contribution in voltage security and the decrease of reactive power which should be bought from generators.