Analysis Of Bidding Equilibrium Of Energy And Ancillary Service Based On Supply Function Model

The new round of power system reform has set off a surge throughout the country in the construction of the spot market and ancillary service market,and the provinces have adopted relevant policies to respond actively.In the deregulated market,generators won't generate according to unified dispatching schedule plan,but by the way of bidding in market.In such an environment,the income of each generator depends on its own bidding strategy and the opponent's bidding strategy,and each rational participant wants to take strategic bidding to maximize their own income.For this purpose,what kind of bidding behavior will the participants have and whether there are potential risks in the market? ……It is very important to predict the bidding behavior of participants in advance.In order to solve this problem,this paper establish a competitive price model of power and ancillary service market based on linear supply function.From the perspective of equilibrium results,the quotation behavior of the participants and the market mechanism are analyzed.The main contents include:First of all,the introduction of Nash equilibrium theory in game theory lays a theoretical foundation for solving market equilibrium.On this basis,several classic market equilibrium models in economics are introduced,and the equilibrium solutions of each model are simply derived by mathematical analysis,and the model is reviewed from the applicability.Then,based on the linear supply function model,a bidding equilibrium model of the power market is established considering the network congestion.On the basis of summarizing the existing solving methods,a bi-level particle swarm optimization(PSO)algorithm is proposed as a supplement.Standard 3-node and IEEE 30-node test system are used to simulate the proposed algorithm,with obtained results similar to the nonlinear complementarity algorithm.Simulation results verify effectiveness of the proposed bi-level PSO algorithm.Compared with the nonlinear complementarity algorithm,the algorithm proposed is more simplified by the cost of time under the premise of ensuring the accuracy of the result,and avoid solving the semismooth nonlinear equations.Then,on the basis of the above model and the solution algorithm,the equilibrium models of bidding sequentially and bidding simultaneously in energy and ancillary market are built respectively,and the bidding behavior of the participants is compared from the perspective of equilibrium solutions.Among them,the objective function is written in the form of expected returns considering the probability of reserve being dispatched.The reserve compensation considers capacity compensation and the power compensation after the dispatched,and the reserve cost is considered as the increase of fuel cost after the dispatched.The simulation results of the above models show that the equilibrium strategy of the energy market is not affected by the reserve market because of the priority transaction in the independent bidding mode.And generator only consider the current market returns and will not consider the potential returns of the future market in the long run.In the joint bidding mode,there is strong coupling between the energy market and the reserve market,and the reserve dispatched rate will affect the quotation coefficient of the generator in energy market.The generator will consider the bid portfolio in the two markets to maximize revenue.Finally,the joint bidding equilibrium model of power and ancillary service market is established considering the participation of extraneous power and interruptible load.Considering the influence of the uncertainty of extraneous power to the additional reserve of the system and the uncertainty of the reserve dispatched.Sensitivity analysis of participants' bidding behavior has been done from three aspects: the characteristics of extraneous power,the demand of load and the mode of reserve cost allocation,and put forward reasonable suggestions on the design of the market mechanism.The results show that the worse the extraneous power' characteristics is,the smaller the quotation coefficient is in the energy market,the higher the quotation coefficient of the inside unit is in the energy market,and the higher the price of the power is.In addition,under the mode of reserve cost is borne by the generator,the increase in cost will stimulate the generator to quote higher prices in the energy market.The excessive energy clearing price causes users to pay more,and the reserve cost is more appropriate borne by users.