Study On Risk Based Congestion Management And Price Control Scheme In Electricity Market

Traditional monopoly has been changed by market deregulation in power industry. Open accesses to all market participants and effective price signals from competition optimize the resource allocation. However, electricity is special merchandise not only in consuming, but also in the transport. After market deregulation, power system reliability has been challenged because of the economic profit maximization,which causes grid congestion, reduced security margin, even instability and blackout. In addition, market competition brings more uncertainty to electricity price and potential risk to market participants. Therefore, enhancing system reliability, improving economy efficiency and avoiding security and price risk are the cores to the market reform.This paper provides a deep discussion on how to incorporate grid security into market price signal and keep price stable. Traditional congestion management is based on deterministic security analysis, which is not able to quantify event probability and severity, and so comprehensive congestion control is not available. In this paper, system congestion risk, which quantify the congestion extent, is defined and applied in the congestion management and nodal price calculation. The result from test system shows risk based congestion management is a flexible way and sends out reasonable price signal.In additional, this paper gives a detail analysis to all factors which have impact on market price and performance. A price control scheme incorporating price forecast is proposed. It suggests that preventive actions should be taken when a big price disturbance is detected in the market, which is supposed to stabilize the market price, reduce risk to market participants. The application of this technique will make market run in a better price performance.