Analysis of Market Equilibrium Based on Co-evolution in Electricity Spot Market

Abstract

By solving the Nash equilibrium of the electricity market, it is possible to observe the game process of market entities under different boundary conditions and predict the future trend of the market. In order to study the state of market equilibrium in the power spot market, firstly we constructed a bi-level equilibrium model. The upper layer is the problem of maximizing the profit of power generation enterprises under the bidding constraint, and the lower layer is the security constraint economic dispatch with the goal of maximizing social welfare. The traditional solution transforms the bi-level model into MPEC or EPEC through optimal conditions, but they are generally non-convex and difficult to solve. In this regard, the coevolution algorithm is used to solve the bi-level model, and it is proved that the result of co-evolution under a limited strategy set is equivalent to the Nash equilibrium. Finally, an example of PJM 5 machine with 5 nodes is used to analyse the power market equilibrium in the spot market.