Dynamic Economic Dispatch And Energy-saving Dispatch Consider Wind/Hydro/Thermal Combined System

With the inereasing requirement of energy demand and depletion of fossil oi1resources gradually, the more and more environmental problems are increasinglyprominent, wind power generation has been paid more attention as a generationapproach of the greatest economic development prospects in renewable energy sources.However, different from conventional generation, wind power brings about a newdemand and challenge for the dispatching of power system due to its uncertainty andvariability. Therefore, the research on the economic dispatch in the power system withwind power plant has importantly theory significance and applied value.Base on the state of power system economic dispatch, the dynamic economicdispatch and energy-saving dispatch considering wind farm、cascade hydroelectricstations and thermal power plants are researched. The main work are as follows:①The dynamic economic dispatch of power system must considers the coupling ofdifferent time sections, it will be more complex when wind power integration intopower system. Base on the dynamic economic dispatch in the power system with windpower and thermal power, this paper considers the influence of cascade hydroelectricstations, the single-object model of dynamic economic dispatch in the power systemwith wind/hydro/thermal is established. The model considers the thermal powers’output and the cascade hydroelectric stations’ flow as controlling variables, withminimize the the generating cost or purchasing cost as the function， the constrainsinclude the output constraints and the ramp speed constraints of thermal power unit、theoutput constraints and the generating flow of cascade hydroelectric stations, the waterbalance constrains of the coupling of different time sections in cascade hydroelectricstations and so on. And the problem is solved by particle swarm optimization (PSO)algorithm. The thermal powers and the cascade hydroelectric stations share the spinningreserve capacity demand brought by wind power forecasting error together; thethermal power unit output range is adjusted dynamically according to the ramp speedconstraints, it distributes the particle around the boundary for improving the globalsearching ability.②With the implementation of the policy of energy conservation and emissionreduction，the operation and scheduling of the power system should not only considerthe economic factors，should also consider reduce coal consumption and pollutants as far as possible. This paper taking the purchasing cost minimum，the coal consumptionand pollution emissions minimum as the objective function, establish themulti-objective model of power system dynamic energy-saving scheduling includingwind/water/thermal power. To avoid the problem which using a weighted methodmerge the multi-objective optimization into the single objective problem existingdimensions are not uniform and it’s too hard to set weight, this paper based on the thenon-dominated sorting genetic algorithm-Ⅱ to solve the model.In the process ofoptimization, determine the dominating relations among individuals through thecalculation of the total limits value of all constraint conditions,to realize the populationof fast non-dominated sorting and congestion calculating thus obtains the pareto optimalsolution set. Then this paper uses fuzzy logic evaluating method select the bestcompromise solution from the set as the final schedule scheme.③Base on the programming environment of MATLAB, the paper calculates thebenchmark instances and actual power system. The results indicate the method ofthermal powers and cascade hydroelectric stations share the spinning reserve capacitytogether.can reducing additional costs significantly, than the method of only thermalpowers undertake the spinning reserve capacity; clean energy resources such as wind、hydro power have the priorities, it can maximize reduces energy consumption andpollutant emission, and optimize the resource collocation.