The Fixed Cost Allocation Method Of Time-sharing Benefits For Wind Power Grid-connection Based On Probability Power Flow

The power industry in China is developing rapidly,the power system is reforming constantly,and the fairness and reasonableness of fixed cost allocation of transmission system is closely related to the future sound development of power industry.In this paper,we focus on the fixed cost allocation of wind power grid-connected environment transmission system.This paper is devoted to study the fixed cost allocation method of power transmission system under large-scale wind power grid-connection environment.The work is mainly divided into three parts.I In the first part,considering the conventional thermal power is easy to control and wind power's volatility,this paper proposes a biggest trend tracking method efficiently,first using the monte carlo sampling method to simulate the wind farm scene,using the method of synchronous cutting back to generation number cut scene,then the system network condition,downstream tracing method and the reverse flow tracing method is used to calculate each wind farms in power system and conventional load to the power supply,each coal-fired plants and conventional load on monthly comprehensive benefits,according to the monthly comprehensive benefit define a maximum efficiency coefficient,Then,each load is removed from the load power supplied by the wind power station,and optimal transaction is conducted according to the maximum benefit coefficient of each pair of thermal power plants and the conventional load pairs.Finally,a 7-node system analysis with wind power station shows that this method makes the wind power grid-connected system save part of the transmission cost.In the second part,considering the different period wind power and load demand fluctuations,especially in the larger fluctuation of period of time,this paper proposes a tracking algorithm,the trend of time-sharing were taken into account to determine wind farms(days,years)with conventional load each time a typical trend data,using trend tracking parsing algorithm for each hour tracking the trend of wind power and conventional load as a result,be determined by the trend tracking results wind farms with the load of each line at the time of peak and valley of maximum allocation of power,to calculate the peak and valley load on the circuit cost allocation proportion coefficient,The cost allocation of each wind power generation and conventional load to each line is determined,while the fixed cost allocation of conventional power supply and conventional load is calculated by the maximum effective trend tracking method.Finally,a wind farm IEEE30 node system is used to verify the fairness,rationality and efficiency of the method.In the third part,considering a single moment of static trend tracking is not fully reflect the uncertainty factors including wind power transmission system,this paper proposes a time-sharing benefit tracking method based on probability wave,wind of probability model is established firstly,using the method of time-sharing benefit trend tracking of line power allocation is calculated for each node.Secondly,the power distribution data of each node is used to calculate the semi-invariants of each order.Finally,the probability density function of tracking results is calculated by Cornish-Fisher series,and the output value of all tracking results is obtained.This method can not only reflect the uncertain factors of wind power transmission system,but also track the power flow data in the whole period.