Research On Interval Optimization And Game Equilibrium Of Integrated Power-Thermal-Gas System With Multiple Community Energy Stations

With the development and application of distributed energy management systems,advanced energy conversion and storage technology,as well as the growing penetration of distributed renewable generation(DG),distributed Community Energy Stations(CES)are becoming increasingly important solutions for local heating,cooling and power supply.Integrated energy systems with multiple CESs show layering and zoning system architectures,autonomous and coordinated operation mode and emerging trend in market-oriented reform.Therefore,related research is needed in the aspects of distributed coordinated energy dispatch and market mechanism considering uncertainty of DGs and demands.Based on integrated power-thermal-gas system with multiple distributed CESs equipped with DGs and energy storage,following works have been carried out:(1)A conceptual framework of the CES system with power,thermal and gas input is established.Treating the uncertainty of DGs and demands as intervals,an interval optimization approach is applied to solve the day-ahead energy dispatch problem of CES.A case study is conducted to show the actual operation of CES under uncertainty.Sensitivity of uncertain interval size to multi-energy input and economic efficiency is also analyzed.(2)Considering reserve for uncertainty,a day-ahead interval dispatching model of thermoelectricity systems with high proportion of wind power generation is proposed.An interval scheduling model of natural gas distribution station is also presented.Consisting of the abovementioned three subsystems,an integrated power-thermal-gas system is built.Distributed and coordinated energy dispatch of the system is realized based on Analytical Target Cascading(ATC).Impact of uncertainty to overall system operation is discussed.(3)Based on the system architecture above,a Stackelberg game framework is applied,where thermoelectricity system and gas station act as two competing leaders and CESs as followers.A fixed-point iterative method based on best responses of followers is employed to obtain the Nash-Stackelberg equilibrium.Relations between energy price and transaction of the equilibrium is studied.Finally,economic efficiency of the game approach is compared with that of the dispatching approach.Thanks to multi-energy complementarity and storage,CESs are able to adjust input energy uncertain intervals according to price signals.Further,by coordination of subsystems,the multi-energy outputs and reserves of the supply side system can be well managed to meet the interval inputs of CESs,which leads to better wind power consumption and economic operation.In addition,the supply-demand Stackelberg game brings higher profit to energy suppliers,but also forces the whole system away from optimality,which shows the necessity of market supervision.