随着风电等间歇性新能源的大规模并网,电网运行状态变化频繁,传统基于典型运行方式计算的输电断面极限传输功率(Total Transfer Capability,TTC)适用性降低。文中提出一种基于数据挖掘的输电断面动态TTC在线构建方法。首先,基于风电和...随着风电等间歇性新能源的大规模并网,电网运行状态变化频繁,传统基于典型运行方式计算的输电断面极限传输功率(Total Transfer Capability,TTC)适用性降低。文中提出一种基于数据挖掘的输电断面动态TTC在线构建方法。首先,基于风电和负荷的超短期预测及预测误差的高阶不确定性,采样生成“风电-负荷”二维数组及相应运行状态集,对部分运行状态计算其TTC,获得用于构建输电断面动态TTC的有标记/无标记知识库;然后,通过混合互信息法选择出与TTC存在强关联的特征属性;最后,利用半监督协同训练,建立TTC偏差与特征属性之间的定量关系,进而得到输电断面动态TTC。算例验证表明,该方法不仅能够基于超短期预测及预测误差的不确定性准确估计输电断面TTC,而且能够量化提供提高TTC的调度信息,同时,采用半监督数据挖掘技术,减少了计算TTC的次数,构建动态TTC速度快,能够较好的适应在线运行方式。展开更多
除物理稳定性引起的输电阻塞外,电力市场和社会福利还受到一次能源、环保排放、技术支撑及多方博弈等因素的制约。这些影响市场竞争和效率的因素可统称为广义阻塞,它们共同约束着电力系统和电力市场的运行。其中,由减排约束造成的能源...除物理稳定性引起的输电阻塞外,电力市场和社会福利还受到一次能源、环保排放、技术支撑及多方博弈等因素的制约。这些影响市场竞争和效率的因素可统称为广义阻塞,它们共同约束着电力系统和电力市场的运行。其中,由减排约束造成的能源流不通畅可称为排放阻塞,受到了越来越多的关注。从机理、特性及时效等方面分析排放阻塞与输电动态阻塞的异同,并在电力市场与电力系统的动态交互仿真平台(dynamic simulation platform for power market&power system,DSPMPS)上深入研究其交互影响。仿真结果表明,排放阻塞和输电阻塞存在复杂的交互影响,应从全局观点出发优化广义阻塞的风险管理。在运营中,建议采用"按各自的机理,分别将各种阻塞风险分摊"的风险分摊方法,对2种阻塞进行综合管理。展开更多
以电力系统为物理基础的电力市场运营受到物理规律与经济规律的双重制约,必须掌握电力市场与电力系统在不同时间尺度上的交互影响以保证其安全稳定。为此,基于电力市场与电力系统的动态交互仿真平台(dy-namic simulation platform for p...以电力系统为物理基础的电力市场运营受到物理规律与经济规律的双重制约,必须掌握电力市场与电力系统在不同时间尺度上的交互影响以保证其安全稳定。为此,基于电力市场与电力系统的动态交互仿真平台(dy-namic simulation platform for power markets&power systems,DSPMPS),通过对各参与者的市场行为与反映客观规律的数学模型之间的动态交互仿真,研究了参与者决策对电力市场与电力系统的短期和长期稳定性的影响、市场行为与输电动态阻塞的相互影响、输电阻塞对投资行为及监管行为的影响。这些初步应用反映了DSPMPS在决策支持与综合型人才培训中的重要作用。展开更多
The dynamic behaviour of power line cables have been a source of interest to researchers ever since the phenomenon was first noticed in the 1920s. Conductor oscillation is mostly caused by the dynamic forces of nature...The dynamic behaviour of power line cables have been a source of interest to researchers ever since the phenomenon was first noticed in the 1920s. Conductor oscillation is mostly caused by the dynamic forces of nature such as wind loading. This imposes a periodic force on the conductors which is highly undesirable. It is therefore important for engineers to account for the possible effect of the wind loading when designing the power line. Investigations have shown that modeling the exact dynamic behaviour of a conductor is very difficult. Based on this fact, getting the exact analytical solution to conductor vibration is difficult, which is almost impossible, hence the numerical approximation becomes an option. This paper presents the developed finite element method used to analyse the dynamic behaviour of transmission line conductors. The developed FEM （finite element method） is implemented on MATLAB. The numerical analysis using MATLAB that is presented in this paper is used to simulate the response of the conductor when subjected to external loading in the time domain. The simulation is used to analyse the transverse vibration of the conductor. The formulation of the stiffness matrix and load vector is done and the results obtained are used to evaluate the conductor＇s internal energy dissipation. This finite element solution is compared with the results documented in literature. This numerical simulation is also used to investigate the effects of varying the axial tension on energy dissipation within the strands. Hence, this evolved in physically appropriate energy characterization process that can be used to evaluate the conductor self-damping with respect to line contact.展开更多
文摘随着风电等间歇性新能源的大规模并网,电网运行状态变化频繁,传统基于典型运行方式计算的输电断面极限传输功率(Total Transfer Capability,TTC)适用性降低。文中提出一种基于数据挖掘的输电断面动态TTC在线构建方法。首先,基于风电和负荷的超短期预测及预测误差的高阶不确定性,采样生成“风电-负荷”二维数组及相应运行状态集,对部分运行状态计算其TTC,获得用于构建输电断面动态TTC的有标记/无标记知识库;然后,通过混合互信息法选择出与TTC存在强关联的特征属性;最后,利用半监督协同训练,建立TTC偏差与特征属性之间的定量关系,进而得到输电断面动态TTC。算例验证表明,该方法不仅能够基于超短期预测及预测误差的不确定性准确估计输电断面TTC,而且能够量化提供提高TTC的调度信息,同时,采用半监督数据挖掘技术,减少了计算TTC的次数,构建动态TTC速度快,能够较好的适应在线运行方式。
文摘除物理稳定性引起的输电阻塞外,电力市场和社会福利还受到一次能源、环保排放、技术支撑及多方博弈等因素的制约。这些影响市场竞争和效率的因素可统称为广义阻塞,它们共同约束着电力系统和电力市场的运行。其中,由减排约束造成的能源流不通畅可称为排放阻塞,受到了越来越多的关注。从机理、特性及时效等方面分析排放阻塞与输电动态阻塞的异同,并在电力市场与电力系统的动态交互仿真平台(dynamic simulation platform for power market&power system,DSPMPS)上深入研究其交互影响。仿真结果表明,排放阻塞和输电阻塞存在复杂的交互影响,应从全局观点出发优化广义阻塞的风险管理。在运营中,建议采用"按各自的机理,分别将各种阻塞风险分摊"的风险分摊方法,对2种阻塞进行综合管理。
文摘以电力系统为物理基础的电力市场运营受到物理规律与经济规律的双重制约,必须掌握电力市场与电力系统在不同时间尺度上的交互影响以保证其安全稳定。为此,基于电力市场与电力系统的动态交互仿真平台(dy-namic simulation platform for power markets&power systems,DSPMPS),通过对各参与者的市场行为与反映客观规律的数学模型之间的动态交互仿真,研究了参与者决策对电力市场与电力系统的短期和长期稳定性的影响、市场行为与输电动态阻塞的相互影响、输电阻塞对投资行为及监管行为的影响。这些初步应用反映了DSPMPS在决策支持与综合型人才培训中的重要作用。
文摘The dynamic behaviour of power line cables have been a source of interest to researchers ever since the phenomenon was first noticed in the 1920s. Conductor oscillation is mostly caused by the dynamic forces of nature such as wind loading. This imposes a periodic force on the conductors which is highly undesirable. It is therefore important for engineers to account for the possible effect of the wind loading when designing the power line. Investigations have shown that modeling the exact dynamic behaviour of a conductor is very difficult. Based on this fact, getting the exact analytical solution to conductor vibration is difficult, which is almost impossible, hence the numerical approximation becomes an option. This paper presents the developed finite element method used to analyse the dynamic behaviour of transmission line conductors. The developed FEM （finite element method） is implemented on MATLAB. The numerical analysis using MATLAB that is presented in this paper is used to simulate the response of the conductor when subjected to external loading in the time domain. The simulation is used to analyse the transverse vibration of the conductor. The formulation of the stiffness matrix and load vector is done and the results obtained are used to evaluate the conductor＇s internal energy dissipation. This finite element solution is compared with the results documented in literature. This numerical simulation is also used to investigate the effects of varying the axial tension on energy dissipation within the strands. Hence, this evolved in physically appropriate energy characterization process that can be used to evaluate the conductor self-damping with respect to line contact.
