IGDT-based Research On Power System Scheduling Considering Demand Respond And Flexible Ramp

Wind power can effectively cope with energy and environmental problems.But wind power has strong randomness and uncertainty.Under the background of changing electricity policy to set up competitive electricity market,decision makers do not have access to the complete wind data.In addition,there are limitations of forecasting techniques and cognitive ability,which makes wind power be more characteristics of Knightian Uncertainty in electric dispatching decision-making field.The traditional solution can’t adapt to this new form of uncertainty.Therefore,this paper conducts specific research on how to deal with the uncertainty of wind power and improve the flexibility of power system.(1)A power system scheduling model based on Information Gap Decision Theory(IGDT)is established.Compared to the previous model,the proposed model simultaneously considers the uncertainty of wind power and load,and the power flow and line safety constraints are considered in this paper.Different decision models are provided for decision makers with different intentions.Specifically,a robust IGDT scheduling model is provided for decision makers with conservative intention in risk aversion strategy,and an opportunistic IGDT scheduling model is provided for decision makers with speculative intention in opportunity seeker strategy.On the premise of guaranteeing the expected scheduling cost,the corresponding uncertainty level and the unit scheduling are obtained,which quantifies the system’s tolerance for uncertainty.Finally,the analysis is examined on Modified IEEE-39 bus system,and the effectiveness and superiority of IGDT model is proved by result analysis and simulated contrast test.(2)The IGDT scheduling model of power system considering demand response(DR)is established.The pricing strategy,response method and uncertainty of DR were analyzed in the process of modeling.IEEE-39 bus system was used to analyze the impact of pricing strategy and response method on IGDT scheduling model,including Real-Time Price(RTP),Time-of-Use Price(TOU),Price-based Demand Response(PDR)and Incentive-based Demand Response(IDR).The results show that DR can effectively improve the robustness and the speculativeness of IGDT.In general,the improvement effect of RTP or IDR was better than that of TOU or PDR,respectively.IEEE-118 bus systems were used to compare the differences between IGDT methods and probabilistic methods in dealing with DR uncertainties.The results show that the computational efficiency of the former is obviously better than that of the latter,especially in considering power flow constraints,which indicates that the IGDT method is more suitable for complex large-scale power systems.(3)The IGDT robust scheduling model considering the flexible ramping is established.The uncertainty of wind power is taken into account in the calculation of flexible ramping requirement,and relating flexible ramping constraints are formulated.In the modified IEEE-118 bus system,first of all,the influence of flexible ramping on robustness of IGDT model is analyzed.And the results show that since the uncertainty of wind power is taken into account when calculating the flexible ramping requirement,the unit can adjust the output power in advance,which absorbs part of the wind power uncertainty,so that the overall uncertainty that the system can accommodate is improved,i.e.the robustness is enhanced.In the next place,the influence of flexible ramping requirement and wind power permeability on the results is studied.The analysis shows that with the increase of uncertainty of net load,the unit operation cost increases accordingly,however,the flexible ramping can significantly reduce the operating cost of the system.Flexible ramping mainly deals with power imbalance in a short time,so there may be large demand for flexible climbing even in the case of low wind power permeability.Finally,reliability evaluation and comparative analysis were conducted.The results show that flexible ramping can improve the reliability of the system.Compared with the deterministic model and the stochastic model,the economics of the established model is better than the former and slightly lower than the latter,but the reliability is the best.