Reliability Assessment On Power System With Large-scale Wind Power Penetration

With the growing scale of power system and the increasing depletion of fossil fuel resources, the development and utilization of renewable energy is attracting more and more attention. Due to the rapid development of wind generation technique and sharply drop of wind power cost, wind power has become an important alternative to traditional power generation sources. As the random and intermittent inherent characteristic of wind energy, the output of the wind turbine is of great fluctuation and difficult to control. The large-scale integrated wind power has an important effect on the security and stability of power system, especially on the reliability of power system.The characteristic of wind power system is analyzed. The element reliability model of power system is established based on the randomness of wind power and the uncertainty of power system operation state. Based on Monte Carlo simulation, the reliability evaluation method of power system considering wind power is proposed. Then, the influence of wind power on power system reliability is studied by the proposed model and method.The main content and research conclusion of this paper are as follows:(1) Background topics. The importance and necessity of studying the effect of wind power on system reliability is pointed out. The current studies of reliability assessment on power system with large-scale wind power penetration are summarized. The main contents of the full text are listed.(2) Power system reliability model. Reliability model is the basis of power system reliability assessment. The Weibull probability distribution model is used to generate wind speed. The output of wind turbines is achieved by using the mathematical relationship between wind speed and active power output. The reliability model of wind turbines is established based on the random characteristic and forced outage rate of wind turbine. Besides, the flow calculation model of wind farm is also established.(3) Basic theory of power system reliability assessment based on Monte Carlo simulation. Monte Carlo simulation is a widely used mathematical method for assessing the reliability of the power system. The basic principles and features of these methods of reliability assessment based on sequential and non-sequential Monte Carlo simulation are introduced. Besides, the advantages and shortcomings between these two methods are compared. The common indicators and calculation methods of these indicators of power system reliability assessment are described. Based on Monte Carlo simulation, the reliability evaluation method of power system considering wind power is proposed. The specific assessment content, procedures and evaluation process of the proposed method is also given.(4) The influence of wind power on power system reliability. By use of the modified IEEE-RTS79 system involving wind power, the influence of the location, mode, capacity of wind power penetrating power system and so on is analyzed. The relevant conclusions are obtained.