提出了包括传统静态安全性和鞍结分岔稳定性的可用输电能力(Available Transfer Capability,ATC)的新模型.该模型将系统安全性约束的众多不等式转化为一个半光滑等式约束方程组,结合鞍结分岔稳定性的约束条件,构建了一类同时考虑安全性...提出了包括传统静态安全性和鞍结分岔稳定性的可用输电能力(Available Transfer Capability,ATC)的新模型.该模型将系统安全性约束的众多不等式转化为一个半光滑等式约束方程组,结合鞍结分岔稳定性的约束条件,构建了一类同时考虑安全性和稳定性的ATC模型的半光滑方程系统.基于光滑化策略和方法,建立了模型求解的Levenberg-Marquardt计算方法.9节点和30节点系统的计算结果表明该模型和计算方法的可行性和有效性.展开更多
对应用柔直技术改善220 kV分区电网性能进行了研究,对220 k V分区电网进行静态安全性分析,考虑线路负载率和节点电压等指标,找出影响分区供电可靠性的因素;在明确薄弱环节后,进行柔性直流分区互联系统的设计,依据N-1故障的严重程度进行...对应用柔直技术改善220 kV分区电网性能进行了研究,对220 k V分区电网进行静态安全性分析,考虑线路负载率和节点电压等指标,找出影响分区供电可靠性的因素;在明确薄弱环节后,进行柔性直流分区互联系统的设计,依据N-1故障的严重程度进行柔直落点设计,之后设计柔直电压等级。通过灵敏度计算分区电网有功功率和无功功率需求,设计柔直容量及控制策略。通过PSD-BPA验证所提方法的有效性,计算结果表明:柔直互联系统投入后,能够缓解重载分区供电压力,实现分区供电能力最大化,故障时可以进行无功支撑,稳定分区电网电压。展开更多
This paper proposes a new type of tri-sectional wheel-based cable climbing robot which is able to climb up vertical cylindrical cables of a cable-stayed bridge. The robot is composed of three pairs of wheels equally s...This paper proposes a new type of tri-sectional wheel-based cable climbing robot which is able to climb up vertical cylindrical cables of a cable-stayed bridge. The robot is composed of three pairs of wheels equally spaced circularly which are joined by six connecting boards to form a whole closed hexagonal body to clasp a cable. The whole design is entirely modular to enable to assenably the robot on-siteeasy eaoily. To analyze the static features of the robot, a mathematical model of climbing is deduced. Furthermore, taking a cable with a diameter of 80mm as an example, we calculate the design parameters of the robot. For safly landing in the case of electrical accident, a centrifugal speed regulator is proposed and applied to consume useless energy generated when the robot is slipping down along the cables. A simplified mathematical model of the landing mechanism is deduced. Finally, several experiments on the climbing mechanism demonstrate that the robot can carry payloads less than 2.2kg to climb up a cable with diameters varying from 65mm to 205mm.展开更多
The approach of available transfer capability （denoted as ATC） incorporating wind generation has been paid very high attention since the development of wind generation. Based on the maximum function, this paper pres...The approach of available transfer capability （denoted as ATC） incorporating wind generation has been paid very high attention since the development of wind generation. Based on the maximum function, this paper presents an ATC model. The characteristic of the new model is twofold. First, it considers wind turbines connected to power system and static security of power system simultaneously. Second, it is a system of semismooth equations and can be solved easily. By using the smoothing strategy, a smoothing Newton method is adopted for solving the proposed new ATC model. Numerical simulation results of the IEEE 30-bus and 118-bus system show that the new model and algorithm are feasible and effective. The impact of wind turbines connected to power system on ATC is also analyzed.展开更多
文摘提出了包括传统静态安全性和鞍结分岔稳定性的可用输电能力(Available Transfer Capability,ATC)的新模型.该模型将系统安全性约束的众多不等式转化为一个半光滑等式约束方程组,结合鞍结分岔稳定性的约束条件,构建了一类同时考虑安全性和稳定性的ATC模型的半光滑方程系统.基于光滑化策略和方法,建立了模型求解的Levenberg-Marquardt计算方法.9节点和30节点系统的计算结果表明该模型和计算方法的可行性和有效性.
文摘对应用柔直技术改善220 kV分区电网性能进行了研究,对220 k V分区电网进行静态安全性分析,考虑线路负载率和节点电压等指标,找出影响分区供电可靠性的因素;在明确薄弱环节后,进行柔性直流分区互联系统的设计,依据N-1故障的严重程度进行柔直落点设计,之后设计柔直电压等级。通过灵敏度计算分区电网有功功率和无功功率需求,设计柔直容量及控制策略。通过PSD-BPA验证所提方法的有效性,计算结果表明:柔直互联系统投入后,能够缓解重载分区供电压力,实现分区供电能力最大化,故障时可以进行无功支撑,稳定分区电网电压。
基金Supported by the National High Technology Research and Development Programme of China （No. 2006AA04Z234） and the China Postdoctoral Science Foundation （ No. 20090461051 ）
文摘This paper proposes a new type of tri-sectional wheel-based cable climbing robot which is able to climb up vertical cylindrical cables of a cable-stayed bridge. The robot is composed of three pairs of wheels equally spaced circularly which are joined by six connecting boards to form a whole closed hexagonal body to clasp a cable. The whole design is entirely modular to enable to assenably the robot on-siteeasy eaoily. To analyze the static features of the robot, a mathematical model of climbing is deduced. Furthermore, taking a cable with a diameter of 80mm as an example, we calculate the design parameters of the robot. For safly landing in the case of electrical accident, a centrifugal speed regulator is proposed and applied to consume useless energy generated when the robot is slipping down along the cables. A simplified mathematical model of the landing mechanism is deduced. Finally, several experiments on the climbing mechanism demonstrate that the robot can carry payloads less than 2.2kg to climb up a cable with diameters varying from 65mm to 205mm.
基金This research is supported by the National Natural Science Foundation of China under Grant Nos. 10871031, 10926189, the Natural Science United Foundation of Hunan-Hengyang under Grant No. 10JJS008, and the Educational Department of Hunan under Grant No. 10A015
文摘The approach of available transfer capability （denoted as ATC） incorporating wind generation has been paid very high attention since the development of wind generation. Based on the maximum function, this paper presents an ATC model. The characteristic of the new model is twofold. First, it considers wind turbines connected to power system and static security of power system simultaneously. Second, it is a system of semismooth equations and can be solved easily. By using the smoothing strategy, a smoothing Newton method is adopted for solving the proposed new ATC model. Numerical simulation results of the IEEE 30-bus and 118-bus system show that the new model and algorithm are feasible and effective. The impact of wind turbines connected to power system on ATC is also analyzed.
