Equilibrium Analysis of Microgrids in Renewable Portfolio Standard-Constrained Spot Market Considering Source-load-storage Interaction

Because of the uncertainty and volatility of renewable energy generation, and the renewable energy curtailment ratio remained stubbornly high, the renewable energy portfolio standard (abbr. RPS) was proposed to promote the development of renewable energy by stipulating the accommodation responsibility of main electricity buyers and consumers to ensure the economic operation of the main part of renewable energy generation. For this reason, it became especially important to analyze the source-load-storage operation strategy and the market equilibrium in electricity market under RPS. Based on RPS rule and electricity spot market a bi-level model was established to analyze source-load-storage interaction equilibrium in the electricity market under RPS: the model of the lower layer contained a day-ahead spot market clearing model an excess consumption trading model, in which the uncertainty of renewable energy generation was considered; based on the time-of-use nodal price and the excess accommodated quantity trading price of the lower layer model the microgrid in the upper layer model optimized the investment, transaction, and operation strategies. The diagonalization algorithm was used to iteratively solve the above-mentioned bi-level equilibrium problem, and taking IEEE 14-bus system for example the feasibility of the established models and algorithm were verified. Results of the verification show that the investment, operation and transaction strategy of microgrid significantly change under RPS, and the accommodated quantity of renewable energy in microgrid is significantly promoted.