Research On Probabilistic Box Power Flow Model And Algorithm Considering Wind Power Uncertainty

In the actual operation of power system with wind farms,the uncertainty of parameters in the system may lead to the deviation and change of wind power output,thus affecting the accurate calculation of power flow,which makes it difficult to evaluate the steady-state operation of power system.Due to the lack of strict regularity of uncertain parameters in traditional uncertain power flow c alculation methods,the distribution and fluctuation range of uncertain parameters are not fully considered.It is easy to cause the problem of lack of information by using the distribution of approximate function or the interval of uncertain parameters.Therefore,in order to explore the impact of uncertain factors on power system operation,this paper uses uncertain parameters wind speed and load as the research object,introduces probability box theory in power flow calculation,and proposes a wind power uncertain power flow model and algorithm based on probability box theory,which improves the accuracy of power flow calculation,Furthermore,the model and algorithm are applied to power flow optimization to seek the best economic benefits,and the effect iveness of the proposed model and algorithm is verified by experiments on IEEE30 standard test system.The main research work of this paper is summarized as follows:(1)According to the distribution and drift range of wind speed,the probability box modeling method of wind speed is designed,which makes the description of wind speed more comprehensive and reduces the complexity of traditional uncertainty modeling.(2)For the power system with wind farms,the random fluctuation of wind speed and load will cause the uncertainty of power flow calculation.Aiming at this problem,the probability box theory is applied to power flow analysis,and a probabilistic interval power flow model with both probability and interval is established.The parameters in t he power flow model are expressed in the form of probability box,The distribution and the change range of power flow can be obtained intuitively,which reflects the overall distribution trend of power flow and improves the accuracy of information expressi on.(3)A power flow calculation method based on probability box is proposed,which makes use of the advantage of discrete calculation of probability box.It not only improves the calculation efficiency,but also reflects the drift of power flow,overcomes the shortcomings of approximate calculation,and achieves the purpose of accurate calculation.(4)In order to better evaluate the security operation,reliability,economic dispatch and operation cost of power system,the power flow optimization of power system is analyzed.Under the condition of the lowest power cost,the uncertain power flow system is optimized.The experimental results show that the probability box method can solve the power flow problem accurately,and compared with the traditional uncertain power flow calculation method,it has better calculation performance.