The component aging has become a significant concern worldwide,and the frequent failures pose a serious threat to the reliability of modern power systems.In light of this issue,this paper presents a power system relia...The component aging has become a significant concern worldwide,and the frequent failures pose a serious threat to the reliability of modern power systems.In light of this issue,this paper presents a power system reliability evaluation method based on sequential Monte Carlo simulation(SMCS)to quantify system reliability considering multiple failure modes of components.First,a three-state component reliability model is established to explicitly describe the state transition process of the component subject to both aging failure and random failure modes.In this model,the impact of each failure mode is decoupled and characterized as the combination of two state duration variables,which are separately modeled using specific probability distributions.Subsequently,SMCS is used to integrate the three-state component reliability model for state transition sequence generation and system reliability evaluation.Therefore,various reliability metrics,including the probability of load curtailment(PLC),expected frequency of load curtailment(EFLC),and expected energy not supplied(EENS),can be estimated.To ensure the applicability of the proposed method,Hash table grouping and the maximum feasible load level judgment techniques are jointly adopted to enhance its computational performance.Case studies are conducted on different aging scenarios to illustrate and validate the effectiveness and practicality of the proposed method.展开更多
In a grid-connected wind farm based on permanent magnet synchronous generators(PMSGs),the wind speed and the number of operating PMSGs are the two most important influencing factors along with the stochastic nature of...In a grid-connected wind farm based on permanent magnet synchronous generators(PMSGs),the wind speed and the number of operating PMSGs are the two most important influencing factors along with the stochastic nature of sub-synchronous oscillation(SSO)from the point view of the farm.This paper proposes a method of unstable SSO risk evaluation for grid-connected PMSG-based wind farms based on the sequential Monte Carlo simulation(SMCS).The determination of critical wind speed(CWS)of SSO and the sequential simulation strategy of wind speed states and PMSG states in a wind farm at the same wind speed(S-WF),as well as in a wind farm at different wind speeds(D-WF),are studied.Five indices evaluating the expectation,duration,frequency and energy loss of SsO risk are proposed.Moreover,a strategy to reduce SsO risk by adjusting the cut-in wind speed is discussed.The effectiveness of the discussed issues in this paper are proved by the case studies of a 750-PMSG wind farm based on the actual wind speed data collected.展开更多
The research on reliability evaluation of an integrated energy system(IES)is of great significance to system planning and operations.The differences of multiple energy subsystems must be considered in reliability eval...The research on reliability evaluation of an integrated energy system(IES)is of great significance to system planning and operations.The differences of multiple energy subsystems must be considered in reliability evaluation of an IES,in which energy quality differences of various energy resources is critical.Current reliability evaluation of an IES cannot uniformly evaluate the reliability of multiple energy subsystems due to neglecting the energy quality differences of various energy resources.To address this problem,a novel reliability evaluation method for IESs based on exergy is proposed for the first time in this paper.The exergy of an energy resource or a substance is a measure of its usefulness,quality or potential to cause change.The models of exergy not supplied minimization and exergy efficiency maximization are proposed to alleviate energy capacity deficiency and transmission component overload in the reliability evaluation of an IES.These two models are compared to analyze exergy efficiency for the proposed method.The energy supply priority strategy of an IES is proposed considering energy quality differences of various energy resources,in which electricity,gas and heating/cooling subsystems are supplied in an orderly manner.Furthermore,a reliability evaluation indices system of an IES based on exergy is proposed in this paper.An extensive case study on an actual IES demonstrates the feasibility and effectiveness of the proposed reliability evaluation method.展开更多
Assessing the reliability of integrated electricity and gas systems has become an important issue due to the strong dependence of these energy networks through the power-to-gas(P2G)and combined heat and power(CHP)tech...Assessing the reliability of integrated electricity and gas systems has become an important issue due to the strong dependence of these energy networks through the power-to-gas(P2G)and combined heat and power(CHP)technologies.The current work,initially,presents a detailed energy flow model for the integrated power and natural gas system in light of the P2G and CHP technologies.Considering the simultaneous load flow of networks,a contingency analysis procedure is proposed,and reliability is assessed through sequential Monte Carlo simulations.The current study examines the effect of independent and dependent operation of energy networks on the reliability of the systems.In particular,the effect of employing both P2G and CHP technologies on reliability criteria is evaluated.In addition,a series of sensitivity analysis are performed on the size and site of these technologies to investigate their effects on system reliability.The proposed method is implemented on an integrated IEEE 24-bus electrical power system and 20-node Belgian natural gas system.The simulation procedure certifies the proposed method for reliability assessment is practical and applicable.In addition,the results prove connection between energy networks through P2G and CHP technologies can improve reliability of networks if the site and size of technologies are properly determined.展开更多
基金supported by the National Natural Science Foundation of China(No.52022016)the Fundamental Research Funds for the Central Universities(No.2023CDJYXTD-004)the Graduate Research and Innovation Foundation of Chongqing(No.CYB22014)。
文摘The component aging has become a significant concern worldwide,and the frequent failures pose a serious threat to the reliability of modern power systems.In light of this issue,this paper presents a power system reliability evaluation method based on sequential Monte Carlo simulation(SMCS)to quantify system reliability considering multiple failure modes of components.First,a three-state component reliability model is established to explicitly describe the state transition process of the component subject to both aging failure and random failure modes.In this model,the impact of each failure mode is decoupled and characterized as the combination of two state duration variables,which are separately modeled using specific probability distributions.Subsequently,SMCS is used to integrate the three-state component reliability model for state transition sequence generation and system reliability evaluation.Therefore,various reliability metrics,including the probability of load curtailment(PLC),expected frequency of load curtailment(EFLC),and expected energy not supplied(EENS),can be estimated.To ensure the applicability of the proposed method,Hash table grouping and the maximum feasible load level judgment techniques are jointly adopted to enhance its computational performance.Case studies are conducted on different aging scenarios to illustrate and validate the effectiveness and practicality of the proposed method.
基金supported by the National Natural Science Foundation of China under Grant(51777066).
文摘In a grid-connected wind farm based on permanent magnet synchronous generators(PMSGs),the wind speed and the number of operating PMSGs are the two most important influencing factors along with the stochastic nature of sub-synchronous oscillation(SSO)from the point view of the farm.This paper proposes a method of unstable SSO risk evaluation for grid-connected PMSG-based wind farms based on the sequential Monte Carlo simulation(SMCS).The determination of critical wind speed(CWS)of SSO and the sequential simulation strategy of wind speed states and PMSG states in a wind farm at the same wind speed(S-WF),as well as in a wind farm at different wind speeds(D-WF),are studied.Five indices evaluating the expectation,duration,frequency and energy loss of SsO risk are proposed.Moreover,a strategy to reduce SsO risk by adjusting the cut-in wind speed is discussed.The effectiveness of the discussed issues in this paper are proved by the case studies of a 750-PMSG wind farm based on the actual wind speed data collected.
基金supported in part by the National Natural Science Foundation of China under Grant No.51637008 and No.U1610122.
文摘The research on reliability evaluation of an integrated energy system(IES)is of great significance to system planning and operations.The differences of multiple energy subsystems must be considered in reliability evaluation of an IES,in which energy quality differences of various energy resources is critical.Current reliability evaluation of an IES cannot uniformly evaluate the reliability of multiple energy subsystems due to neglecting the energy quality differences of various energy resources.To address this problem,a novel reliability evaluation method for IESs based on exergy is proposed for the first time in this paper.The exergy of an energy resource or a substance is a measure of its usefulness,quality or potential to cause change.The models of exergy not supplied minimization and exergy efficiency maximization are proposed to alleviate energy capacity deficiency and transmission component overload in the reliability evaluation of an IES.These two models are compared to analyze exergy efficiency for the proposed method.The energy supply priority strategy of an IES is proposed considering energy quality differences of various energy resources,in which electricity,gas and heating/cooling subsystems are supplied in an orderly manner.Furthermore,a reliability evaluation indices system of an IES based on exergy is proposed in this paper.An extensive case study on an actual IES demonstrates the feasibility and effectiveness of the proposed reliability evaluation method.
文摘Assessing the reliability of integrated electricity and gas systems has become an important issue due to the strong dependence of these energy networks through the power-to-gas(P2G)and combined heat and power(CHP)technologies.The current work,initially,presents a detailed energy flow model for the integrated power and natural gas system in light of the P2G and CHP technologies.Considering the simultaneous load flow of networks,a contingency analysis procedure is proposed,and reliability is assessed through sequential Monte Carlo simulations.The current study examines the effect of independent and dependent operation of energy networks on the reliability of the systems.In particular,the effect of employing both P2G and CHP technologies on reliability criteria is evaluated.In addition,a series of sensitivity analysis are performed on the size and site of these technologies to investigate their effects on system reliability.The proposed method is implemented on an integrated IEEE 24-bus electrical power system and 20-node Belgian natural gas system.The simulation procedure certifies the proposed method for reliability assessment is practical and applicable.In addition,the results prove connection between energy networks through P2G and CHP technologies can improve reliability of networks if the site and size of technologies are properly determined.
