Research On Clearing Strategy Of Supply And Demand Participating In Reserve Market Under The Condition Of Wind Power Integration

With the accelerated pace of China’s energy transition,the installed capacity and gridconnected ratio of wind power is rising,and its randomness and volatility significantly increase the risk to the smooth operation of the power system,which needs to maintain a sufficient amount of standby.However,the traditional way of determining standby capacity according to the fixed proportion of system load does not take into account the impact of wind power grid connection,and is no longer applicable to the determination of standby capacity of current wind power systems with high proportion.In addition,China continues to promote the construction process of the electricity market,and the importance of the standby auxiliary service market as one of the key links is self-evident.In the dual-side open market,both supply-side thermal units and demand-side interruptible load can be used as standby resources to improve system reliability and economy.Therefore,it is significant to study the optimal clearing strategy for both supply and demand side participation in the standby market under grid-connected wind power conditions.In this paper,uncertainties affecting operational standby demand are addressed and a standby demand determination method based on reliability indicators is proposed.Based on this,we construct a model of the standby market clearing strategy with both supply and demand participation and set up various comparison scenarios to analyze the results.Specifically,the main work of this paper is as follows.First,for the problem of determining the optimal standby capacity of wind powercontaining systems,this paper deals with the uncertainties affecting the standby demand(unit failure outage,load and wind power forecast errors,and wind power volatility)and quantifies the relationship between the probability of loss of load and system upward standby,and the probability of wind abandonment and system downward standby.A reliability index-based standby requirement determination method is proposed to set the loss of load probability and wind abandonment probability values so that the system meets the desired risk level.The minimum system standby demand under this desired risk level is then obtained,which is used as the basis for the subsequent study of the standby market clearing strategy involving both supply and demand sides.Secondly,for the optimization problem of supply and demand side participation in standby market clearing,the supply side thermal power units and demand side interruptible loads are considered to jointly provide standby auxiliary services,and the lowest combined cost of system power supply and standby is taken as the objective function,and the system power balance,thermal power units and interruptible loads characteristics,the minimum standby capacity limit of the system under the specified reliability level,and the line tide safety are taken as the constraints to construct the model of supply and demand side participation in standby market clearing strategy,and the improved chaotic adaptive firefly algorithm and algorithm flow are given for the model solution.Finally,the system standby demand and the results of the supply and demand side participation in the standby market are solved through the simulation of the algorithm.On this basis,three comparison scenarios,namely,single supply-side participation in the standby market,single demand-side participation in the standby market,and dual supply-side participation in the standby market without considering the impact of grid-connected wind power,are set up to compare and analyze the system reliability and economics with the dual supply-side and demand-side participation in the standby market clearing strategy constructed in this paper.The results of system standby demand determination show that the reliability index-based system standby demand determination method proposed in this paper can reserve reasonable standby according to the level of wind power uncertainty.The higher the uncertainty of wind power output,the more reserve capacity the system needs to reserve to meet the same reliability level.The results of the supply and demand side participation in the standby market clearing show that the joint supply and demand side participation in the standby market can make the system more economical than the single supply side or single demand side participation in the standby market while meeting the system reliability.Considering only supply-side thermal units to provide standby,the overall system economy decreases at the same reliability level(0.05 probability of load loss and 0.05 probability of wind abandonment),with unit operating cost increasing by 6.94%,supply-side standby cost increasing by 23.87%,and overall system cost increasing by 1.68%.Considering only the demand-side interruptible load to provide backup,the lack of system backup capacity leads to a lower reliability level,and the comprehensive system economy decreases,with the cost of wind abandonment penalty and outage compensation cost accounting for 9.1%of the comprehensive system cost,and the comprehensive system cost increases by 1.72%.The main innovation points of this paper are as follows.(1)A comprehensive consideration of the fourfold uncertainty of forced outage of generating units,load forecast error,wind power output power forecast error and wind power volatility,and the construction of a reliability index-based system standby demand determination model,which can better reserve reasonable standby capacity according to the level of wind power uncertainty.(2)Constructed a standby market clearing strategy model with both supply and demand participation to meet the specified reliability level,and gave an improved chaotic adaptive firefly algorithm and algorithm flow for model solving.