Day-ahead Dispatching Optimization For Integrated Energy Systems Considering Gas/Thermal Intertia

The integrated energy system in the development,conversion,storage,transportation,dispatching,consumption and other aspects through cross-energy,energy management systems that span energy and multi-temporal coordination can be constructed according to the characteristics of various energy sources and related energy conversion equipment.Eliminate intermittent renewable energy and achieve efficient use of multiple energy cascades.With the rapid development of electric/gas/heat integrated energy systems,more indepth research on energy dispatching for electric/gas/heat integrated energy systems is urgently needed.Based on the typical structure of electric/gas/heat integrated energy system,the paper analyzes the multi-energy flow coupling relationship,clarifies the specific meaning of the inertia in the energy transmission,conversion and consumption links,and analyzes the multi-energy flow scheduling mechanism and gas of the integrated energy system.The iPact of thermal inertia on the development of a multi-energy flow scheduling program.For the large-scale cross-regional integrated energy system,based on the analysis of the difference between the pressure and mass flow dynamic balance process of the gas pipeline,the gas pipeline is decomposed into a limited number of small-scale equal-length pipe elements on each pipe element.Based on the improved Line-Pack model considering the time difference of pressure and mass flow balance,a general refinement model for natural gas systems with multi-scale natural gas pipelines was established.For the central heating system,the thermal network and building thermal inertia were comprehensively considered.The node method establishes the delay model of the heat network transmission,and uses the temperature correction equation to describe the heat loss.Combined with the energy use nature of the heating season heating user,the building thermal inertia model is established to restrain the room temperature from fluctuating within a certain range.Furthermore,an integrated energy system optimization scheduling model considering gas/thermal inertia is constructed.By introducing a linear function of heating extraction steam quantity based on production simulation,the electric power adjustment interval of CHP unit is optimized,integrated into the daily dispatching model,and linearity is given.The solution is designed to accommodate large-scale problem solving.Through simulation analysis,the existence of gas-heat inertia of natural gas and heat medium during transmission is verified,and the relationship between pipe network scale and gas/thermal inertia is analyzed.The improved Line-Pack model,which takes into account the gas inertia,can be applied to multi-scale long-distance gas pipeline networks,and the length of the tube element has a certain influence on the calculation results and the calculation duration.The heating load power curve considering thermal inertia is more mechanical.The calculated curve is shifted to the right as a whole and is more gradual.The electric dispatching model of the electric/gas/heat integrated energy system utilizes the complementary advantages of the gas network and the heat network to further explore the benefit potential of the integrated dispatching operation and proves the necessity of taking the inertia of the gas in the electric/gas/heat integrated energy system.