Research Of The Grid Energy-saving Scheduling Based On Thermoelectric Load Conversion

The detailed rules for the implementation of energy-saving power generationscheduling approach indicate that the power load of coal-fired cogenerationunit(CHP) is arranged by the principle of hot determining power and the wind powerwithout adjustment ability has the first generation priority. But the power grids of"Three North"(Northeast, North China, Northwest) areas are mainly constituted bycoal power and cogeneration units occupy a larger proportion while thehydroelectric power with a good regulation performance is severely lacking.InWinter as the increasing of peak-vale difference and the capacity of wind powerintegration the drought period of hydropower unit, the heating period of thethermoelectric unit, the blow period of wind turbines and the anti peakingcharacteristics of the wind power superimpose on each other, leading to thedifficulty of the peak-load regulation of the power system and the phenomenon ofabandonding the wind frequently. As a result, how to increase the wind powerconsumptive capacity of "Three North" areas power grids is the urgent problem oftheir energy-efficient scheduling.Firstly, considering the existing scheduling method which simulates all coalunits with condensing units can’t realize the combination optimization ofthermoelectricity load and the problem that the heat load influences the wind powerconsumptive capacity, the paper investigates modeling methods of large thermalpower units. Based on detailed analysis of the operating characteristics of varioustypes of cogeneration units such as condensing,unit back-pressure unit andcondensate pumping unit,as well as relations between the thermoelectric load andoperating condition figures, the paper establishes the model of the consumption oflarge thermal power units.Secondly, based on the above model, the paper constructed a new type ofenergy-saving scheduling model whose electrical load is balanced by the wholenetwork unit while the heat load is balanced by the thermal power plants, themaximum output of the wind turbine is the forecast output and the abandoned windpower is punished. The paper studys an algorithm using application tracking centertrajectory interior-point method to solve the new energy-saving scheduling methodand improves the solving process in order to enhance the convergence speed of thealgorithm.Thirdly,In this paper,we give a new explanation of the grid wind powerconsumptive rate, and analyze how the thermal load and the proportion of thermalpower generating units affects grid wind power consumptive rate in details based on the optimal scheduling results. Then we proposed a new scheme to improve gridwind power consumptive rate through reducing the peak heat load and improvingelectrical load valley value by thermoelectric load conversion.Finally, based on typical thermoelectric conversion device(heat pump), wepropose an energy-saving scheduling method that makes much conveniency forcalculating the thermoelectric load conversion. Accordingly, we can makequantitative analysis how the thermoelectric load conversion rate affects the gridwind power consumptive rate, grid total coal consumption and profits for thethermal power plant.The result illuminates that thermoelectric load conversion canreduce grid abandon air volume and conduct thermoelectric conversion loadproperly can reduce grid coal consumption with no damage to economic benefits ofthe thermal power plant.