Study On Long-and Mid-term Operation Strategies And Schedules Of Hydro-dominated Power System In Electricity Markets

The latest electricity market reform brings new challenges to the power system operation.For hydro-dominated power system,how to carry out the market transactions for large and small hydropower stations effectively,how to reduce the effect of inflow uncertainty on market profit,how to guarantee the safe and stable operation of the system under market mechanisms are main challenges.This dissertation takes electricity transaction in Yunnan as the research background,and focuses on key issues of potential market power abuse of giant cascaded hydropower stations,profit analysis of large-scale small hydropower stations,safe and stable operation of the hydro-dominated power system,and effect of different market mechanisms on market operation situations.Four researches are carried out from the viewpoint of long-and mid-term operation strategies and schedules of hydro-dominated power system in electricity markets,which are operation regulation of giant cascaded hydropower stations,profit analysis of large-scale small hydropower stations,contracted generation security check,and simulation modeling of market operation situations.Main contents are introduced as follows:(1)Operation regulation strategy of cascaded hydropower stations in electricity markets.A comprehensive indicator composed of market prices and electricity consumption is proposed to evaluate the situation of hydro-dominated market operation.The two-level operation and regulation model is then proposed to achieve the optimal market operation regulation in hydro-dominated electricity markets.Moreover,an iterative algorithm is proposed to investigate the strategic behaviors of power suppliers and simulate the operation of the market.Furthermore,an integrated solution methodology based on market simulation and multi-core parallel tabu genetic algorithm is proposed to provide optimal regulation strategy for policy makers.Results from case studies with real data based on Yunnan' s electricity market demonstrate that the proposedmethod is effective and efficient.(2)Market operation profit model of lareg-scale SHP considering correlation.The proposed method takes large-scale small hydropower stations in one area as a coalition,first analyze the correlation between different areas,and then create Copula function to describe and produce generation capacity simulation and prediction.Then reconstruction based on typical generation capacity is used to make the simulation and prediction satisfies the actual characteristic of small hydropower generation capacity.Based on that,two potential transaction mechanisms for small hydropower are introduced,and profit analysis models under different market mechanisms are built to study the profit of large-scale small hydropower stations in the market.Moreover,market profit and non-market profit are calculated and compared based on Yunnan's electricity market.(3)Security check strategy of contracted generation and transaction schedules analysis method.In the security check of monthly generation contracts,security check and multistage coordination strategy are proposed to check whether safe and stable power system operation is satisfied,and to determine upper limits of contracts for different stations.After that,an integrated method is presented for making transaction schedules for balancing stations.Monthly load curve is simulated based on the typical daily load curve and weekly proportion coefficient.An improved load shedding method coupled with knowledge rules and load reconstruction strategy is proposed to analyze transaction schedules for balancing stations.The proposed methods are effective and efficient for verifying the feasibility and the executability of the contracted generation,as demonstrated in the case studies.(4)Modeling and Analysis of market operation situation under different market mechanisms.This study focuses on the effects of different market mechanism and parameters on market clearing price and electricity production based on the background of China's latest power industry reform.Firstly,the competition in the combination market of pool and listing is describe as a two-dimensional non-cooperative game with complete information.Then,agent-based model is introduced to simulate the operation of the market and obtain the optimal bidding strategies of power suppliers.Moreover,unconstraint two-dimensional game model is used and the analytic solutions of the model is derived to study the effect of different market mechanisms on market operation,and the effect of different market parameters on market clearing price and electricity production in the market.