Research On Virtual Energy Storage Characteristics And Control Strategy For Thermostatically Controlled Load

With the development of advanced metering infrastructure,interest subjects of power system become diversification,and the interaction between power supply and demand has become feasible for solution of the problem of energy shortage,then the demand response technology has emerged as the times require.The TCL(thermostatically controlled load)is an important part of the demand response,the storing energy ability of whose indirectly can reduce the peak load,improve operation reliability of power grid and enhance emergency ability at the expense of small affecting the users’ comfort.Compared with the traditional supply scheduling,TCLs participating in the demand response has the advantages of fast speed,low cost and high resource utilization rate.Therefore,study on TCLs participating in the demand repose is significant.Based on the virtual energy storage characteristics of the TCLs,the VES(virtual energy storage)model is built.Control strategy of one-type and trunked dispatching are proposed and optimized.The main researches are as follows.(1)This paper divides TCLs into three types,resistance-type,fixed speed compressor-type and inverter compressor-type on account of the operation characteristics.A practical VES model is presented,including two parts: electrical parameter part based on operation characteristics of TCLs;heat parameter part based on equivalent thermal parameter model.(2)For simplified calculation,part of model is dealt with discretization and linearization.Analyzing the control functions and constraints of different VESs,the VSOC(virtual state of charge)-priority control strategy for three types are proposed,respectively.The actual feasibility and control effectiveness of the proposed method are verified by examples.(3)The theoretical basis for the unsatisfactory control effect of the VSOC-priority control strategy for resistor-type and fixed speed compressor-type are deeply studied,which is that the state distribution of the VESs have a high correlation with the control effectiveness.Control algorithm is optimized to maintain the diversity of the VESs during the demand response,and control effectiveness can be improved greatly.(4)It is studied that the tracking effect and influence on control effect of different power vacancies and communication time intervals in the VSOC-priority optimized control strategy.A VSOC-priority trunked dispatching is proposed for solving the problem that TCLs with different types and needs can’t participate in the demand response simultaneously.This paper proposes VES model with high practical value,which fully reflects the influence of different TCLs participating in the demand response on the distribution grid.Then a VSOC-priority trunked dispatching is proposed to realize that various TCLs with different types and needs participate in the demand response at the same time.The VES model of TCLs provides simple control foundation for coordinate control simultaneously with electric vehicles and advanced energy storage.which is of great significance to new energy consumption intelligent power utilization.