In recent years,as a promising option to improve the overall efficiency of energy utilization and absorptive capacity of renewable energies,the integrated energy system(IES)has raised great interest in academies and i...In recent years,as a promising option to improve the overall efficiency of energy utilization and absorptive capacity of renewable energies,the integrated energy system(IES)has raised great interest in academies and industries.Multi-energy flow(MF)calculation,which differs from the traditional power flow calculation,plays a basic role in analyzing IES.MF calculation based on Newton-Raphson method has been proposed in literature,but its calculation efficiency is not high.In this paper,a fast decoupled MF(FDMF)calculation method for IES is proposed.Its main idea is to replace the original Jacobian matrix of MF calculation based on Newton-Raphson method with a diagonal and constant Jacobian matrix by the transformation.The simulations demonstrate that the proposed FDMF method can increase the calculation efficiency by at least 4 times with high calculation accuracy.展开更多
The modeling and multi-energy flow calculation of an integrated energy system (IES) are the bases of its operation and planning. This paper establishes the models of various energy sub-systems and the coupling equipme...The modeling and multi-energy flow calculation of an integrated energy system (IES) are the bases of its operation and planning. This paper establishes the models of various energy sub-systems and the coupling equipment for an electricity-gas-thermal IES, and an integrated multi-energy flow calculation model of the IES is constructed. A simplified calculation method for the compressor model in a natural gas network, one which is not included in a loop and works in constant compression ratio mode, is also proposed based on the concept of model reduction. In addition, a numerical conversion method for dealing with the conflict between nominal value and per unit value in the multi-energy flow calculation of IES is described. A case study is given to verify the correctness and speed of the proposed method, and the electricity-gas-thermal coupling interaction characteristics among sub-systems are studied.展开更多
With the wide application of integrated energy systems(IES),the degree of coupling between different types of energy sources is further strengthened,and the mechanism of fault development tends to be complicated.There...With the wide application of integrated energy systems(IES),the degree of coupling between different types of energy sources is further strengthened,and the mechanism of fault development tends to be complicated.Therefore,in order to improve the accuracy and practicability of the reliability assessment of IESs,a sequential simulation reliability assessment method considering multi-energy flow and thermal inertia is proposed in this paper.In this method,the IES structure model is constructed with the combined cooling,heating and power(CCHP)unit as the core equipment,combining with the new energy source to realize the comprehensive energy power flow calculation considering any loss.Then,a load reduction optimization model is established,considering the importance of load and operational economy,in the system status analysis.Furthermore,the heat supply reliability index is corrected taking into account the transmission delay characteristics and terminal thermal inertia.A case study based on the 20-node and the analysis of the influence factors demonstrates the validity of the proposed method.展开更多
基金supported in part by the National Natural Science Foundation of China(No.51777067)the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(No.LAPS2019-08)the scientific and technological project of State Grid Corporation of China“State Estimation of Integrated Energy Systems Considering Different Time Scales”(No.52110418002R)
文摘In recent years,as a promising option to improve the overall efficiency of energy utilization and absorptive capacity of renewable energies,the integrated energy system(IES)has raised great interest in academies and industries.Multi-energy flow(MF)calculation,which differs from the traditional power flow calculation,plays a basic role in analyzing IES.MF calculation based on Newton-Raphson method has been proposed in literature,but its calculation efficiency is not high.In this paper,a fast decoupled MF(FDMF)calculation method for IES is proposed.Its main idea is to replace the original Jacobian matrix of MF calculation based on Newton-Raphson method with a diagonal and constant Jacobian matrix by the transformation.The simulations demonstrate that the proposed FDMF method can increase the calculation efficiency by at least 4 times with high calculation accuracy.
基金supported by National Natural Science Foundation of China(52077193).
文摘The modeling and multi-energy flow calculation of an integrated energy system (IES) are the bases of its operation and planning. This paper establishes the models of various energy sub-systems and the coupling equipment for an electricity-gas-thermal IES, and an integrated multi-energy flow calculation model of the IES is constructed. A simplified calculation method for the compressor model in a natural gas network, one which is not included in a loop and works in constant compression ratio mode, is also proposed based on the concept of model reduction. In addition, a numerical conversion method for dealing with the conflict between nominal value and per unit value in the multi-energy flow calculation of IES is described. A case study is given to verify the correctness and speed of the proposed method, and the electricity-gas-thermal coupling interaction characteristics among sub-systems are studied.
文摘With the wide application of integrated energy systems(IES),the degree of coupling between different types of energy sources is further strengthened,and the mechanism of fault development tends to be complicated.Therefore,in order to improve the accuracy and practicability of the reliability assessment of IESs,a sequential simulation reliability assessment method considering multi-energy flow and thermal inertia is proposed in this paper.In this method,the IES structure model is constructed with the combined cooling,heating and power(CCHP)unit as the core equipment,combining with the new energy source to realize the comprehensive energy power flow calculation considering any loss.Then,a load reduction optimization model is established,considering the importance of load and operational economy,in the system status analysis.Furthermore,the heat supply reliability index is corrected taking into account the transmission delay characteristics and terminal thermal inertia.A case study based on the 20-node and the analysis of the influence factors demonstrates the validity of the proposed method.
