Research On Robust Peak Shaving For Power System With Integration Of A Large Scale Of Wind Power Generation

In order to solve the problem of energy shortage and environmental pollution,wind power generation develops rapidly due to its non-pollution and abundance of wind resources.However, since wind energy is influenced by variational weather conditions, wind power generation possesses obvious intermittent, randomness and anti-peaking nature. As a large scale wind power generation was integrated into power system, the uncertainty of wind power output would increase the difficulty of peak shaving, even threaten the safe and stable operation of power system. The robust optimization method does not need to assume the distribution function of a random variable and the optimization result possesses high stability. Therefore, the article has study peak shaving for power system with integration of a large scale of wind power generation based on robust optimization theory.Large-scale wind power access will put forward higher requirements for peak shaving of power system. Because pumped storage units possess the characteristics of fast start-up and shut-down and increasing or decreasing the load quickly, a model was proposed for peak shaving for power system considering the pumped storage power stations. It uses primal dual interior point method to get solutions. Based on AMPL simulation platform, through the example of improved IEEE-14 bus system analysis, the results showed that peak-valley difference rate of the equivalent load declines, the number of boot units reduces and operation cost of power system decreases when the pumped storage power station participated in output distribution.In allusion to the randomness of wind power generation, deviation between estimated and actual value of wind power output was defined as the wind disturbance power. Based on robust optimization theory, perturbation scope of wind power output was depicted by cassette uncertain set and line power flow constraints contained uncertain wind power output was fabricated. A model was proposed for robust peak shaving with cassette set for power system considering uncertain wind power output. For the purposes of solving the proposed model conveniently, it is simplified by optimized duality theory to a normal nonlinear programming problem. Finally, through the example of improved IEEE-14 bus system analysis,the simulation shows that when perturbation scope increases to a certain extent, thermal power units need to retrim generated output to ensure the safety of line power flow, so operational cost raises.By further consideration to the randomness of load, based on robust optimization theory, perturbation scope of wind power output and load was depicted by cassette uncertain set and line power flow constraints contained uncertain wind power output and load was fabricated. A model was proposed for robust peak shaving with cassette set for power system considering uncertain wind power output and load. The paper has got output of generating units and operational cost within different perturbation scope of wind power output and load by simulating calculation, and has provided an important reference for peak shaving for power system with integration of wind power generation.