Research On Optimal Reactive Power Of The Power System Considering Wind Uncertainty

As an important problem in the field of power system analysis,the research of reactive power optimization has undergone many years of development and accumulated a lot of rich research results,which is of great significance to save energy,improve voltage quality and improve the reliable operation of power grid.However,with the continuous development of wind power,the wind power penetration rate of the grid continues to grow rapidly.Based on the traditional research work carried out by the deterministic model,it has been unable to cope with the huge challenge of the power system reactive power and voltage problem,which makes it more necessary to consider the influence of wind power uncertainty more deeply in the study of reactive power optimization.Therefore,this paper takes optimal reactive power method of the power system considering wind uncertainty as the research focus,carries on the wind power uncertainty analysis,research of the power system reactive power optimization model considering wind uncertainty,research of random variable processing and model solving method,and other four aspects of research work.Firstly,based on the actual operation data,analyzing the uncertainty of wind power output and grid voltage,the correlation between wind power output and voltage fluctuation.By obtaining the 95%confidence interval of the wind power fluctuation rate and the grid voltage fluctuation rate,the possible fluctuation range of the wind power output and the grid point voltage at different time scales can be grasped for a certain period of time.At the same time,the correlation analysis between wind power output and voltage fluctuation shows that with the increase of wind power output level,the greater the fluctuation of grid voltage and the increase of system uncertainty.Based on the stochastic programming model with stochastic programming theory,a two-stage reactive power optimization model of power system with wind power uncertainty is proposed.The model takes the safe operation of the system as a constraint and considers different types of reactive power Compensating the adjustment characteristics of the equipment to minimize the operating cost of the discrete reactive power compensation equipment as the first stage optimization target,and making a decision on the discrete reactive power compensation equipment such as the capacitor before the random variable occurs to avoid discretization when the random variable occurs Type reactive power compensation equipment to the frequent or unreasonable action;to optimize the cycle of the average loss of the network as a second stage optimization target,not only can compensate for the first stage of the decision-making caused by the reactive power shortage,but also can respond to random variables rapid fluctuations or In the event of a fault,a large amount of reactive demand is generated in a short time.On the basis of comparing several random variable processing methods,the three-point estimation method is used to deal with the random variables in the model,and the stochastic optimization problem is transformed into the deterministic optimization problem.The simulation results verify the accuracy of the three-point estimation method and Simplicity.The improved particle swarm optimization algorithm is used to solve the model.Firstly,the adjustment of the inertia weight parameter and the initial operation are improved by combining the cloud model theory and the chaos theory.Secondly,in the direction of guiding the global optimal particle flight,a migration operation is introduced The results show that the improved particle swarm optimization algorithm has a high quality.Finally,an example is given to demonstrate the effectiveness of the proposed method.The method takes into account the randomness of the wind power during the cycle and avoids the frequent or unreasonable action of the discrete reactive power compensation equipment caused by the random fluctuation of the wind power.The voltage quality of the wind farm is reduced,the network loss in the optimization period is reduced,and the effective cooperation of the discrete and continuous reactive power compensation equipment is realized,and the reactive power and voltage caused by the rapid fluctuation of the wind power in the optimization period are reasonably dealt with.