A Sensitivity Analysis Based Interaction Investigation And Security Assessment In Integrated Electric And Gas Energy Systems

Integrated energy systems(IES),because of their many advantages such as considering multi-energy complementarity,collaboration and optimization,making full use of renewable energy,and improvement of energy utilization,is bound to become the main form of future energy systems.The emergence of IES has made the coupling and interaction between traditional energy systems closer,and at the same time it has also brought more complicated security issues.This security issue is particularly prominent in typical Integrated electric and gas energy system(IEGES).Therefore,this paper focuses on the operation security of the IEGES.This paper propose a sensitivity analysis approach to explore the interaction coupling mechanism between the electric power systems and natural gas system in IEGES,and the develop an improvement approach to enhance the operational security of the IEGES.The main research work is as follows:First,this article explored the characteristics of IEGES subsystems and coupling elements,and a tightly coupled IEGES models is modeled.Gas turbines and P2G equipment are used in this model to achieve two-way energy interaction in IEGES.Gas turbines and P2G equipment are used in this model to achieve two-way interaction of energy flow.Subsequently,an extended Newton-Raphson based solution method is adopted to solve the multi-energy flow(MEF)of the IEGES.Then,based on the MEF calculation,identify the weak nodes in the system.The MEF calculation result of the IEGES-33 test system integrating IEEE 33-bus system and I1-node gas system verifies the applicability of Newton-Raphson method in IEGES;Further,by changing the operating state of the system and calculating the MEF under different operating states of the system,the characteristics of the MEF in IEGES and the characteristics of energy interaction and coupling were preliminarily analyzed.According to the solved multi-energy flow of the IEGES,the sensitivity analysis approach is proposed to calculate the voltage amplitude-gas load sensitivity matrix and the natural gas system node pressure-power system node active sensitivity matrix to explore the interaction coupling mechanism between the electricity and gas systems in IEGES.Further,the sensitivity analysis is used to help the weak nodes of IEGES,which violate the operation constraint,detect and locate the critical underlying causes,and give the useful improvement to mitigate the operation security of IEGES.The performance of the proposed approach is evaluated by the IEGES-24 test system integrating IEEE 24-bus system and Belgian 20-node gas system.The results demonstrate that proposed the sensitivity analysis approach can be used to reveal the interaction coupling mechanism of IES and analyze the operational security.