Power system equipment outages are one of the most important factors affecting the reliability and economy of power systems.It is crucial to consider the reliability of the planning problems.In this paper,a generation...Power system equipment outages are one of the most important factors affecting the reliability and economy of power systems.It is crucial to consider the reliability of the planning problems.In this paper,a generation expansion planning(GEP)model is proposed,in which the candidate generating units and energy storage systems(ESSs)are simultaneously planned by minimizing the cost incurred on investment,operation,reserve,and reliability.The reliability cost is computed by multiplying the value of lost load(VOLL)with the expected energy not supplied(EENS),and this model makes a compromise between economy and reliability.Because the computation of EENS makes the major computation impediment of the entire model,a new efficient linear EENS formulation is proposed and applied in a multi-step GEP model.By doing so,the computation efficiency is significantly improved,and the solution accuracy is still desirable.The proposed GEP model is illustrated using the IEEE-RTS system to validate the effectiveness and superiority of the new model.展开更多
在新能源环境下,负荷需求与新能源发电的不确定性对备用容量对提出了更高的要求,新能源与备用替代日益受到关注。根据电量不足期望值(expected energy not supplied,EENS)与备用容量的关系,确定了电力系统备用总量,并采用优先分配方式...在新能源环境下,负荷需求与新能源发电的不确定性对备用容量对提出了更高的要求,新能源与备用替代日益受到关注。根据电量不足期望值(expected energy not supplied,EENS)与备用容量的关系,确定了电力系统备用总量,并采用优先分配方式在多类型的发电机组中分配备用容量。基于EENS与运行成本,构建光伏发电系统替代火电机组的综合替代效益评价指标,以综合替代效益评价指标的数值最小化为目标函数,构建考虑光伏发电系统替代火电机组参与备用运行的电力系统备用容量优化模型。并用分段线性理论对具有二次特性的目标函数进行线性化处理,采用分支定界算法求解构建的非线性整数规划问题。以IEEE-30系统作为实例,计算结果表明,光伏发电系统替代火电机组参与备用运行,可以降低综合替代效益及备用容量。展开更多
The reliability level of a power generation system is an important problem which is concerned by both electricity producers and electricity consumers. Why？ It is known that the high reliability level may result in ad...The reliability level of a power generation system is an important problem which is concerned by both electricity producers and electricity consumers. Why？ It is known that the high reliability level may result in additional utility cost, and the low reliability level may result in additional consumer＇s cost, so the optimum reliability level should be determined such that the total cost can reach its minimum. Four optimization models for power generation system reliability are constructed, and the proven efficient solutions for these models are also given.展开更多
There is a general concern that the increasing penetration of electric vehicles(EVs)will result in higher aging failure probability of equipment and reduced network reliability.The electricity costs may also increase,...There is a general concern that the increasing penetration of electric vehicles(EVs)will result in higher aging failure probability of equipment and reduced network reliability.The electricity costs may also increase,due to the exacerbation of peak load led by uncontrolled EV charging.This paper proposes a linear optimization model for the assessment of the benefits of EV smart charging on both network reliability improvement and electricity cost reduction.The objective of the proposed model is the cost minimization,including the loss of load,repair costs due to aging failures,and EV charging expenses.The proposed model incorporates a piecewise linear model representation for the failure probability distributions and utilizes a machine learning approach to represent the EV charging load.Considering two different test systems(a 5-bus network and the IEEE 33-bus network),this paper compares aging failure probabilities,service unavailability,expected energy not supplied,and total costs in various scenarios with and without the implementation of EV smart charging.展开更多
为保证电力系统可靠运行,日前机组组合应考虑电网中不确定性因素所带来的风险。大规模风电并网给电力系统运行引入了更多的不确定性,电网互联一定程度上可削弱风电不确定性对电网运行的影响,但同时也增大了日前机组组合问题的复杂度。...为保证电力系统可靠运行,日前机组组合应考虑电网中不确定性因素所带来的风险。大规模风电并网给电力系统运行引入了更多的不确定性,电网互联一定程度上可削弱风电不确定性对电网运行的影响,但同时也增大了日前机组组合问题的复杂度。为了在有限的计算时间内获取计及风险的可行的机组组合方案,需要筛选典型场景来衡量电网运行风险。在风电、负荷预测误差的基础上设置了互联电网机组、联络线强迫停运场景集,构建了互联电网弃风电量期望(expected wind power curtailed,EWPC)和电量不足期望(expected energy not supplied,EENS)风险量化指标,并将其以罚函数的形式引入目标函数,建立了计及多场景运行风险的多区域互联电网安全约束机组组合模型,经两区域12节点系统验证了机组组合策略的正确性和有效性。展开更多
Nowadays,utilities aim to find methods for improving the reliability of distribution systems and satisfying the customers by providing the continuity of power supply.Different methodologies exist for utilities to impr...Nowadays,utilities aim to find methods for improving the reliability of distribution systems and satisfying the customers by providing the continuity of power supply.Different methodologies exist for utilities to improve the reliability of network.In this paper,demand response(DR)programs and smart charging/discharging of plug-in electric vehicles(PEVs)are investigated for improving the reliability of radial distribution systems adopting particle swarm optimization(PSO)algorithm.Such analysis is accomplished due to the positive effects of both DR and PEVs for dealing with emerging challenges of the world such as fossil fuel reserves reduction,urban air pollution and greenhouse gas emissions.Additionally,the prioritization of DR and PEVs is presented for improving the reliability and analyzing the characteristics of distribution networks.The reliability analysis is performed in terms of loss of load expectation(LOLE)and expected energy not served(EENS)indexes,where the characteristics contain load profile,load peak,voltage profile and energy loss.Numerical simulations are accomplished to assess the effectiveness and practicality of the proposed scheme.展开更多
This paper presents a security constrained unit commitment(SCUC)suitable for power systems with a large share of wind energy.The deterministic spinning reserve requirement is supplemented by an adjustable fraction of ...This paper presents a security constrained unit commitment(SCUC)suitable for power systems with a large share of wind energy.The deterministic spinning reserve requirement is supplemented by an adjustable fraction of the expected shortfall from the supply of wind electric generators(WEGs),computed using the stochastic feature of wind and loosely represented in the security constraint with scenarios.The optimization tool commits and dispatches generating units while simultaneously determining the geographical procurement of the required spinning reserve as well as load-following ramping reserve,by mixed integer quadratic programming(MIQP).Case studies are used to investigate various effects of grid integration on reducing the overall operation costs associated with more wind power in the system.展开更多
基金supported by project of State Grid Shandong Electric Power Company(52062520000Q)the National Key Research and Development Program of China(2019YFE0118400)。
文摘Power system equipment outages are one of the most important factors affecting the reliability and economy of power systems.It is crucial to consider the reliability of the planning problems.In this paper,a generation expansion planning(GEP)model is proposed,in which the candidate generating units and energy storage systems(ESSs)are simultaneously planned by minimizing the cost incurred on investment,operation,reserve,and reliability.The reliability cost is computed by multiplying the value of lost load(VOLL)with the expected energy not supplied(EENS),and this model makes a compromise between economy and reliability.Because the computation of EENS makes the major computation impediment of the entire model,a new efficient linear EENS formulation is proposed and applied in a multi-step GEP model.By doing so,the computation efficiency is significantly improved,and the solution accuracy is still desirable.The proposed GEP model is illustrated using the IEEE-RTS system to validate the effectiveness and superiority of the new model.
文摘在新能源环境下,负荷需求与新能源发电的不确定性对备用容量对提出了更高的要求,新能源与备用替代日益受到关注。根据电量不足期望值(expected energy not supplied,EENS)与备用容量的关系,确定了电力系统备用总量,并采用优先分配方式在多类型的发电机组中分配备用容量。基于EENS与运行成本,构建光伏发电系统替代火电机组的综合替代效益评价指标,以综合替代效益评价指标的数值最小化为目标函数,构建考虑光伏发电系统替代火电机组参与备用运行的电力系统备用容量优化模型。并用分段线性理论对具有二次特性的目标函数进行线性化处理,采用分支定界算法求解构建的非线性整数规划问题。以IEEE-30系统作为实例,计算结果表明,光伏发电系统替代火电机组参与备用运行,可以降低综合替代效益及备用容量。
基金This project was supported by the National Natural Science Foundation of China (70373017) .
文摘The reliability level of a power generation system is an important problem which is concerned by both electricity producers and electricity consumers. Why？ It is known that the high reliability level may result in additional utility cost, and the low reliability level may result in additional consumer＇s cost, so the optimum reliability level should be determined such that the total cost can reach its minimum. Four optimization models for power generation system reliability are constructed, and the proven efficient solutions for these models are also given.
文摘There is a general concern that the increasing penetration of electric vehicles(EVs)will result in higher aging failure probability of equipment and reduced network reliability.The electricity costs may also increase,due to the exacerbation of peak load led by uncontrolled EV charging.This paper proposes a linear optimization model for the assessment of the benefits of EV smart charging on both network reliability improvement and electricity cost reduction.The objective of the proposed model is the cost minimization,including the loss of load,repair costs due to aging failures,and EV charging expenses.The proposed model incorporates a piecewise linear model representation for the failure probability distributions and utilizes a machine learning approach to represent the EV charging load.Considering two different test systems(a 5-bus network and the IEEE 33-bus network),this paper compares aging failure probabilities,service unavailability,expected energy not supplied,and total costs in various scenarios with and without the implementation of EV smart charging.
文摘为保证电力系统可靠运行,日前机组组合应考虑电网中不确定性因素所带来的风险。大规模风电并网给电力系统运行引入了更多的不确定性,电网互联一定程度上可削弱风电不确定性对电网运行的影响,但同时也增大了日前机组组合问题的复杂度。为了在有限的计算时间内获取计及风险的可行的机组组合方案,需要筛选典型场景来衡量电网运行风险。在风电、负荷预测误差的基础上设置了互联电网机组、联络线强迫停运场景集,构建了互联电网弃风电量期望(expected wind power curtailed,EWPC)和电量不足期望(expected energy not supplied,EENS)风险量化指标,并将其以罚函数的形式引入目标函数,建立了计及多场景运行风险的多区域互联电网安全约束机组组合模型,经两区域12节点系统验证了机组组合策略的正确性和有效性。
文摘Nowadays,utilities aim to find methods for improving the reliability of distribution systems and satisfying the customers by providing the continuity of power supply.Different methodologies exist for utilities to improve the reliability of network.In this paper,demand response(DR)programs and smart charging/discharging of plug-in electric vehicles(PEVs)are investigated for improving the reliability of radial distribution systems adopting particle swarm optimization(PSO)algorithm.Such analysis is accomplished due to the positive effects of both DR and PEVs for dealing with emerging challenges of the world such as fossil fuel reserves reduction,urban air pollution and greenhouse gas emissions.Additionally,the prioritization of DR and PEVs is presented for improving the reliability and analyzing the characteristics of distribution networks.The reliability analysis is performed in terms of loss of load expectation(LOLE)and expected energy not served(EENS)indexes,where the characteristics contain load profile,load peak,voltage profile and energy loss.Numerical simulations are accomplished to assess the effectiveness and practicality of the proposed scheme.
文摘This paper presents a security constrained unit commitment(SCUC)suitable for power systems with a large share of wind energy.The deterministic spinning reserve requirement is supplemented by an adjustable fraction of the expected shortfall from the supply of wind electric generators(WEGs),computed using the stochastic feature of wind and loosely represented in the security constraint with scenarios.The optimization tool commits and dispatches generating units while simultaneously determining the geographical procurement of the required spinning reserve as well as load-following ramping reserve,by mixed integer quadratic programming(MIQP).Case studies are used to investigate various effects of grid integration on reducing the overall operation costs associated with more wind power in the system.
