Research On The Grid’s Adopt Capacity For Wind Power Considering Security,Stability And Wind Power Efficiency

As the most competitive low carbon energy, wind power has a significant effect on lowering levels of system energy consumption, reducing greenhouse gases and pollutants emissions. With the world energy structure adjusting, China’s wind power industry has sustained a strong growth momentum, and the scale of wind power also showed an overall upward trend year after year. Due to the strong fluctuation of wind, on the premise of meeting the requirements of the safe and stable operation of power grid, integrated wind power will cause conventional thermal unit deviates from the area of economic operation, start and stop frequently, which leads to system cost rising, greenhouse gases and pollutants increasing. Power grid has to pay additional costs to absorb a high level of wind power. At present, renewable energy law endows wind power with scheduling priority in China to guarantee its complete absorption. With the expansion of the scale of wind power planning and construction, the capacity of integrated wind power increases rapidly. Promoting wind power absorption by means of policies and regulations is worth reflection.Complete absorption of wind power brought pressure to bear on Shandong power grid dispatching operation until the renewable energy law revised in 2010. Considering the grid condition,network structure,load characteristics and the characteristics of wind power in Shandong province,it is impossible for power grid dispatching institutions to absorb integrated wind power completely.The proportion of thermal power installed is very big. Subject to the peak shaving capacity, acceptance of wind power has been difficult. Especially during the heating period in winter, it is frequent to limit the output capacity of wind power in the off-peak load period, in order to ensure the security of system. According to historical operation data, wind power is seriously limited in Shandong power grid. It is necessary to conclude the adopt capacity of wind power constrained by transmission capacity and the peak shaving capacity in Shandong power grid.Wind power is intermittent, unpredictable and uncontrollable, so dispatching of power grid with large-scale wind must be considered in the process of designing power market mechanism. With the planning and construction of millions of kilowatt wind power bases, the adjustment ability of the conventional units may not be enough to cover the fluctuations of wind power. It is more meaningful to design effective mechanisms to make the units outside the province participate in the operation inside and build an unblocked scheduling and the market-oriented relations around the surrounding provinces, and it will lead to a good coordination of the peak shaving capacity within a wide range. In this way, wind energy can be used more efficiently in a larger range.Based on the power supply condition, network construction, load characteristics and wind characteristics of Shandong province, a power system transient simulation model is established in PSASP, analyzing the influence of large-scale wind power on grid’s safe and stable operation. It cooperates with Shandong Power gird for short circuit test in Rongcheng to reassess the short circuit capacity ratio method of guiding the construction of wind farms centralized access to one point; Secondly, in view of the factors limiting wind power adopt capacity for provincial power grid, adopt capacity for wind power calculation model is built based on peak shaving capacity. The peak shaving capacity conventional thermal power unit, pumped storage power plant and tie line will be taken into account. In addition, coincidence factor between load and wind power as well as coincidence factor among wind plants will be considered. Wind power adopt capacity of Shandong province is calculated month by month, considering power grid peak shaving capacity constraint at the same time. Finally, in order to solve the sharp contradiction between complete absorption of wind power and the economics, keep the flexibility of dispatching wind power in the practical operation with Renewable Portfolios Standards (RPS).In this case, we can make full use of the resources of neighboring provinces to reduce wind curtailment and improve the utilization rate of wind power.