Method for obtaining multiple-wind farm capacity credit based on Copula function

Abstract

The invention discloses a method for obtaining multiple-wind farm capacity credit based on a Copula function. The method comprises converting a wind speed time sequence into a wind farm power output time sequence by considering the wake effects of wind farms, performing state merging on the sequence according to numerical values and then performing nonlinear fitting to obtain the edge distribution of the power outputs of the individual wind farms, descripting the correlativity of the power outputs of the individual wind farms by selecting a Clayton Copula function for describing lower fat tail characteristics, performing parameter estimation on the selected Copula function by use of a two-stage maximum likelihood method according to the historical power output data of the wind farms to obtain the related parameters of multiple-wind farm power output joint probability distribution, making the multiple-wind farm power output joint probability distribution of the Clayton Copula function equivalent to a multi-state units which are integrated with a power generation system, and obtaining the wind farm capacity credit by use of chord length iteration based on an equal reliability criterion. The method for obtaining the multiple-wind farm capacity credit based on the Copula function is capable of assessing the significance of wind power generation in the aspects such as system reliability, economic efficiency and environmental pollution reduction quickly and accurately in a better way.

Description

technical field [0001] The invention belongs to the technical field of power system operation including wind farms, and more specifically relates to a method for obtaining capacity reliability of multiple wind farms based on a Copula function. Background technique [0002] With the increasing maturity of wind power technology and the effective incentives of national policies for the development of clean and environmentally friendly new energy, China's abundant wind energy resources are gradually being developed, and the installed capacity of wind power continues to grow. By the end of 2012, the cumulative installed capacity of wind power in China had reached 75.32 million Kilowatts, compared to 2007, an increase of about 13 million kilowatts, is expected to exceed 100 million kilowatts by the end of the "Twelfth Five-Year Plan". Due to the randomness and intermittent nature of the output of wind farms, wind power was initially regarded as a completely unreliable form of powe...

AI Technical Summary

Problems solved by technology

Due to the randomness and intermittent nature of the output of wind farms, wind power was initially regarded as a completely unreliable form of power generation, which only provided energy and could not provide power generation capacity.

In fact, no power generation method is completely reliable. There is only a quantitative difference between wind power and conventional power generation in terms of equipment availability, and there is no essential difference

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