Thyristor valve is one of the key equipments for ultra high voltage direct current(UHVDC) power transmission projects.Before being installed on site,they need to be tested in a laboratory in order to verify their oper...Thyristor valve is one of the key equipments for ultra high voltage direct current(UHVDC) power transmission projects.Before being installed on site,they need to be tested in a laboratory in order to verify their operational performance to satisfy the technical specification of project related.Test facilities for operational tests of thyristor valves are supposed to enable to undertake more severe electrical stresses than those being applied in the thyristor valves under test(test objects).On the other hand,the stresses applied into the test objects are neither higher nor lower than specified by the specification,because inappropriate stresses applied would result in incorrect evaluation of performance on the test objects,more seriously,would cuase the damage of test objects with expensive cost losing.Generally,the process of operational tests is complicated and performed in a complex synthetic test circuit(hereafter as STC),where there are a lot of sensors used for measuring,monitoring and protection on line to ensure that the test circuit functions in good condition.Therefore,the measuring systems embedded play a core role in STC,acting like "eyes".Based on the first project of building up a STC in China,experience of planning measuring systems is summarized so as to be referenced by related engineers.展开更多
An accurate fault location algorithm for double-circuit series compensated lines is presented.Use of two-end unsynchronized measurements of current and voltage signals is considered.The algorithm applies two subroutin...An accurate fault location algorithm for double-circuit series compensated lines is presented.Use of two-end unsynchronized measurements of current and voltage signals is considered.The algorithm applies two subroutines,designated for locating faults on particular line sections,and additionally the procedure for selecting the valid subroutine.The subroutines are formulated with use of the generalized fault loop model and the distributed parameter line model is applied.Performed ATP-EMTP based evaluation has shown the validity of the derived fault location algorithm and its high accuracy.展开更多
处于改建阶段的智能变电站采样模式复杂,继电保护装置难以发现采样回路轻微异常,导致回路隐患暴露时间严重滞后。针对上述问题,分析改建时期智能变电站的采样模式和二次设备配置情况,提出基于同源录波数据比对的继电保护采样回路异常检...处于改建阶段的智能变电站采样模式复杂,继电保护装置难以发现采样回路轻微异常,导致回路隐患暴露时间严重滞后。针对上述问题,分析改建时期智能变电站的采样模式和二次设备配置情况,提出基于同源录波数据比对的继电保护采样回路异常检测方法。首先,利用双向编码器表征(bidirectional encoder representations from transformers,BERT)语言模型与余弦相似度算法,实现同源录波数据的通道匹配。然后,利用重采样技术和曼哈顿距离完成波形的采样频率统一与时域对齐。最后,基于动态时间规整(dynamic time warping,DTW)算法提出改进算法,并结合采样点偏移量共同设置采样回路的异常判据。算例分析表明,该方法可以完成录波数据的同源通道匹配,实现波形的一致性对齐,并且相比于传统DTW算法,改进DTW算法对异常状态识别的灵敏性和准确性更高。根据异常判据能够有效检测继电保护采样回路的异常状态,确保了智能变电站的安全可靠运行。展开更多
基金Project Supported by National Development and Reform Commission(No.[2006]2709)
文摘Thyristor valve is one of the key equipments for ultra high voltage direct current(UHVDC) power transmission projects.Before being installed on site,they need to be tested in a laboratory in order to verify their operational performance to satisfy the technical specification of project related.Test facilities for operational tests of thyristor valves are supposed to enable to undertake more severe electrical stresses than those being applied in the thyristor valves under test(test objects).On the other hand,the stresses applied into the test objects are neither higher nor lower than specified by the specification,because inappropriate stresses applied would result in incorrect evaluation of performance on the test objects,more seriously,would cuase the damage of test objects with expensive cost losing.Generally,the process of operational tests is complicated and performed in a complex synthetic test circuit(hereafter as STC),where there are a lot of sensors used for measuring,monitoring and protection on line to ensure that the test circuit functions in good condition.Therefore,the measuring systems embedded play a core role in STC,acting like "eyes".Based on the first project of building up a STC in China,experience of planning measuring systems is summarized so as to be referenced by related engineers.
文摘An accurate fault location algorithm for double-circuit series compensated lines is presented.Use of two-end unsynchronized measurements of current and voltage signals is considered.The algorithm applies two subroutines,designated for locating faults on particular line sections,and additionally the procedure for selecting the valid subroutine.The subroutines are formulated with use of the generalized fault loop model and the distributed parameter line model is applied.Performed ATP-EMTP based evaluation has shown the validity of the derived fault location algorithm and its high accuracy.
文摘处于改建阶段的智能变电站采样模式复杂,继电保护装置难以发现采样回路轻微异常,导致回路隐患暴露时间严重滞后。针对上述问题,分析改建时期智能变电站的采样模式和二次设备配置情况,提出基于同源录波数据比对的继电保护采样回路异常检测方法。首先,利用双向编码器表征(bidirectional encoder representations from transformers,BERT)语言模型与余弦相似度算法,实现同源录波数据的通道匹配。然后,利用重采样技术和曼哈顿距离完成波形的采样频率统一与时域对齐。最后,基于动态时间规整(dynamic time warping,DTW)算法提出改进算法,并结合采样点偏移量共同设置采样回路的异常判据。算例分析表明,该方法可以完成录波数据的同源通道匹配,实现波形的一致性对齐,并且相比于传统DTW算法,改进DTW算法对异常状态识别的灵敏性和准确性更高。根据异常判据能够有效检测继电保护采样回路的异常状态,确保了智能变电站的安全可靠运行。