| Self-supplied power plants(SSPP),with huge installed and production capacity,are indispensable extensive resources in power system.Better management and utilization of SSPP not only remarkably benefit the economy,but also improve the stability of the power grid.Recently,the development of SSPP with comprehensive utilization of resources has been strongly supported by many government policies.And providing peak shaving service according to the power generation and consumption characteristics of SSPP has been considered as its most potential operation mode.However,complete modeling of the power generation and consumption characteristics of SSPP is still challenging.Because,different from the single power generation characteristics of public power plants,the power generation of SSPP is strongly coupled with the power load of enterprises.Therefore,building a personalized power generation and consumption model according to different types of enterprises with consideration of the coupling relationship,and further studying its optimized operating strategy are in great need.Iron and steel enterprises,as the typical representative of high energy consuming enterprises with large regulation ability at load side,are generally equipped with SSPP,having significant impact on the policies and operation strategies of SSPP.Therefore,the iron and steel enterprises are chosen as the research object to study their power generation and consumption characteristics and optimized operating decisions.First,the power load is modeled according to production procedures of the enterprises.The power generation model of the SSPP units is prosed based on the classification of pure surplus gas power generation and gas-coal mixed combustion power generation.With the consideration of the relationship among power generation,gas and power consumption system,the coupling model of power generation/consumption system with/without flexible power load is proposed as the foundation of the following research on optimized decisions.Then,an evaluation method is developed for the power generation characteristics of SSPP utilizing mixed multiple surplus gas,which is constructed from the perspective of potential and capability of power generation,respectively.The main power consumption cost of the enterprises,including fuel cost,maintenance cost,penalty cost of pollutant emission,penalty cost of surplus gas emission and cost of electricity purchase and sales,is also well modeled.Through the optimization model aiming at minimizing the power consumption cost,the evaluation for power generation characteristics under normal and abnormal conditions is successfully performed.What’s more,the method for optimized decisions of enterprises participating in incentive demand response are proposed.Considering the adjustable feature of the power load,the coupling model between electricity and gas system in different production procedure is constructed.The incentive demand response model is established on stepped subsidy.From the perspective of the antifluctuation ability and the capacity,the gas storage cost and the penalty cost model of excess emission are also developed.Through the comparison and analysis of the optimized response decisions and response results of the incentive demand response with/without gas container system,the regulation potential of adjustable power load and SSPP are well revealed.It is also concluded that the participation of SSPP in incentive demand response benefits both the stability of power grid and economic and environmental-friendly production of enterprises.Finally,the method for optimized decisions of enterprises participating in price-based demand response are proposed.According to the transferable feature of the power load,the coupling model between electricity and gas system in each production procedure at transfer in and out moment is constructed.The upper and lower boundaries of transfer rate are determined by three power load transfer models based on consumer psychology,including peak-flat model,peak-valley model,and flat-valley model.The price-based demand response model considering the transfer in/out times,the transfer in/out power and the post transfer timing constraints is also performed.With these models,the response capability from the generation and load side and optimized decisions in price-based demand response with/without the gas container system are carefully evaluated and analyzed.The strategy for power generation and consumption of enterprises participating in price-based demand response is optimized.It is found that the gas container system can decouple the power generation and consumption system,bringing better flexibility. |
