Research On CHP Units' Operating Characteristic And The Wind Power Accommodation Capacity Using The Electrical Boiler To Compensate Power Peak Load

Due to its good performance,such as non-pollution,low cost,and sustainable development,etc.wind power has been vigorously pursued in recent years.With the growing installed capacity of wind power,the power grid wind curtailment problem has become increasingly prominent as a result of the deficiency of peak regulation ability for electricity.Especially during winter heating period in the "three north"(northeast,north China,northwest)region which constitute the largest unit of the thermal power in our country,conventional peaking power is relatively lacking without peak regulation as cogeneration units' peaking capacity is the main factor in determining the wind power consumption situation.In order to make the most of the wind power,this paper studied the wind power accommodation capacity under the constrain of the power peak load regulation,and uses peaking compensation to utilize the electric boiler to promote the regulation of the power grid peak load,thus improving the wind power consumptive ability and eliminating the waste of the wind power.To study the wind power consumptive ability of the cogeneration units,first,this paper introduces the operating principle of the CHP(Combined Heat and Power)units briefly,and then analyzes the regulation ability of the CHP units while working in a "heat-electric" operating way in which the CHP units play a dominant role in distributing the power producing.Next,taking the constrain of power peak regulation into consideration,this paper constructs the optimization model with targets of the minimized total costs of system and the minimized wind curtailment costs.The simulation result illustrated that,under the "heat-electric" operating constraints,the output from CHP units will make it difficult to regulate the peak load,thus making the output from CHP units forms greater proportion of the extraction steam cogeneration units,the more heat load,the greater unit power output in constant heat load,the weaker regulation ability of system peaking capacity,the less consumptive wind power.In order to ensure the heat supply,the "heat-electric" operating will weaken the regulation ability for the power peak load.To solve this problem,according to the analysis of three practicable solutions,this paper chose to use the electric boiler to promote the regulation ability of power peak load of the CHP units,thus improvingthe wind power consumptive ability.It is difficult to illustrate the running characteristic and principle of the CHP units after utilizing the electric boiler in graphic methods,in this way,this paper proposed a new function of operation characteristics along with the new constrained equations of both operation and the balance between heat and power is obtained to analyze the change in system's peaking capacity and wind power accommodation capacity,Then,a multi-objective model that targets at maximizing both wind power accommodation and economic benefit of CHP plant is built,which helps to work out a compatible energy-saving dispatch for both objectives.Simulation results show that the peaking compensation is necessary and feasible,and can get more CHP units involved in peak regulation.Besides,suitable compensation price can not only reduce the wind power curtailment,but also improve the economic performance of CHP plants and decrease carbon emissions.