Market Power Risk Assessments Of Multi-type Markets Participants Considering Reliability In Electricity Markets

The power industry has the characteristics of natural public utilities and services.The reform of the power system effects the national economy and the people's livelihood,which should take the potential market power risks into account.Market power abuse will decrease the efficiency of market operation,distort price signal and do harm to both the reasonable benefits of market participants and wealth of whole society.Plenty of current researches on market power assessment and market power management mechanisms have already formed.They are rich in content and different in emphases.In addition,the deepening penetration of renewable energies(RES)and flexible demand resources(FDRs)bring inherent variability and uncertainty to system operation,and it is re-shaping the way in which market are operated.The emerging electricity markets,such as Chinese,are springing up nowadays.They are at different development stages and having distinctive features.The expression of market power is changing along with the rapid development of electricity.Considering large-scale penetration of RES,the increase of peak-to-valley difference in demand side,the complex risks,the reliability of power systems,and the higher proportion of FDRs in smart grid,this paper proposes market power assessement methods both in supply and demand side.The subjects in this study include the traditional generation units,distributed pumped-storage units,electricity retailers,and the FDRs.In supply side,a bi-level optimization market power assessement model for traditional generation units is proposed.Taking wind power as an example,the market power is quantified with high proportion of RES.In addition,this paper analyses the realistic problems such as high proportion of intermittent energy fluctuations,equipment failures,large fluctuations in load,and slow climb of large units.The typical mechanism of market power of the distributed pumped-storage units is clarified.Based on the system network reliability,optimal power flow(OPF),and probability method,the market power of the distributed pumped-storage units is quantitatively evaluated.In demand side,based on the centralized market models and the interconnection between day-ahead and real-time market,this paper summarizes the beha'viors of retailers,which can be divided into three categories.The behaviors could further constitute four typical scenes.Models and indicators are proposed to quantify the market power of electricity retail oligarches.Furthermore,based on the network topology,random failures,and the probabilistic multi-state system operation states,four market power evaluation indicators for FDRs are proposed,which realizes the effective identification of the key FDR nodes.