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101.
102.
Yu. V. Raskovalov E. M. Tolstikova 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2006,40(4):258-261
A set of measures that can be implemented by the Relay-Protection and Automated-Equipment Service for Centralized Dispatch
Regulation (CDR) in Siberia to determine the location of damage sustained by inter-system 550-and 220-kV transmission lines
maintained by the United Power System (UPS) of Siberia, and the methodology and technology of damage-location determination
(DLD) are described. The damage sustained by the 500-kV high-voltage lines (HL), and the accuracy of DLD relative to zero-sequence
emergency parameters are analyzed statically.
__________
Translated from élektricheskie Stantsii, No. 5, pp. 59–62, May, 2006. 相似文献
103.
104.
Naoki Takinami Takashi Chino Shotaro Yoshida Isao Miura Kazuo Watanabe Kazuo Amano 《Electrical Engineering in Japan》1994,114(6):1-12
When ground-fault problems occur on a cable line, immediate fault location and restoration are required. Therefore, various new methods to locate the fault point instantaneously have been investigated to replace such conventional methods as the Murray loop method and the pulse radar method [1]. These methods require a long time to locate the fault point. One possible fault location method is to sense the temperature rise following a ground fault using a fiber optic distributed temperature sensor. Application of this method was found feasible through sensing the temperature rise at a ground-fault test using a thermocouple as a temperature sensor with test cables [4]. A power/optical composite cable was prepared experimentally and after verifying its thermal mechanical performance, the temperature rise at an incidence of a fault was determined and the anticipated performance was demonstrated in a ground-fault test. This article describes the outline of the test. 相似文献
105.
非平稳ARMA信号自校正滤波器及其应用 总被引:2,自引:1,他引:1
本文处理带白色观测噪声的非平稳ARMA信号估计问题.应用状态空间方法和现代时
间序列分析方法[1],基于ARMA新息模型,提出了非平稳ARMA信号自校正滤波器,推广了
Hagander和Wittenmafk的结果[2],并给出了在雷达跟踪系统和检测数据数字滤波方面的应
用.仿真结果说明了本文结果的实用性和有效性. 相似文献
106.
107.
108.
109.
文中提出了一种应用RBF神经网络对标准IMM算法中的卡尔曼滤波结果进行校正的方法。网络输人为预测误差、卡尔曼增益以及测量值与估计值之差.网络输出反映了由于目标机动所带来的滤波误差.将网络输出结果和直接由卡尔曼滤波求解得到的结果相加.可以得到更为准确的滤波值。同时.在网络的学习算法中.在网络权值矩阵的修正公式中增加了反映滤波残差的调整项.若卡尔曼滤波的残差较大,网络调整权值的幅度也相应增大。仿真结果表明.在目标发生机动转弯处.校正后的IMM算法的跟踪误差要明显小于标准IMM算法的跟踪误差.跟踪精度较高。 相似文献
110.
High accuracy path tracking for vehicles in presence of sliding: Application to farm vehicle automatic guidance for agricultural tasks 总被引:1,自引:0,他引:1
Roland Lenain Benoit Thuilot Christophe Cariou Philippe Martinet 《Autonomous Robots》2006,21(1):79-97
When designing an accurate automated guidance system for vehicles, a major problem is sliding and pseudo-sliding effects. This is especially the case in agricultural applications, where five-centimetre accuracy with respect to the desired trajectory is required, although the vehicles are moving on slippery ground. It has been established that RTK GPS was a very suitable sensor to achieve automated guidance with such high precision: several control laws have been designed for vehicles equipped with this sensor, and provide the expected guidance accuracy as long as the vehicles do not slide. In previous work, further control developments have been proposed to take sliding into account: guidance accuracy in slippery environments has been shown to be preserved, except transiently at the beginning/end of curves. In this paper, the design of this control law is first recalled and discussed. A Model Predictive Control method is then applied in order to preserve accuracy of guidance even during these curvature transitions. Finally, the overall control scheme is implemented, and improvements with respect to previous guidance laws are demonstrated through full-scale experiments. 相似文献