A new partial discharge online detecting equipment based on TEV method is introduced in this paper. Its application to 3~35kV metal-enclosed switchgear partial discharge detection is clarified by an instance. Advice for improvement is also presented.

An on-line monitoring system of vacuum pressure for 35KV vacuum tube is designed in this paper. The operation principle, hardware structure and software plan are explained in details. The system can valuate the internal pressure of the vacuum tube by monitoring the static charge of the shields using electrical field sensors with rotating electrode. At the same time, the data-collecting machine and the controller are developed for long-range and on-line monitoring. The result shows that such system runs steadily and reliably. It can estimate the vacuum degree accurately laying 35cm from the vacuum tube. Besides, it is steady and anti-jamming with less-cost.

—In view of the inefficiency of coding, the complexity of signal extraction and the strict demands of machining in the existing multiple SAW tags system, an anti-collision technique based on Walsh Code was proposed. First, it encodes the 2PSK using the single antenna transmission structure, then it implements the orthogonal encoding of each tag in a multiple SAW tags system using Walsh coding, and finally the encoding information of each tag is acquired by reading the echo signals from the reader and doing cross-correlation operation with each code block in the orthogonal code-set. The proposed approach incorporates both the coding efficiency and the processing technology, simplifies the complexity of signal extraction, and achieves the goal of anti-collision of multiple SAW tags system. The theoretical analysis and simulation verify the feasibility of this technique.

Various harmonics exist in the electrical power system, and the harmonics include both integer harmonics and non-integer harmonics. It is hard to analyze all the harmonics accurately. In order to improve the precision of harmonic analysis and the minimum resolution, this paper presents a new algorithm named binary scale time windows FFT based on traditional algorithm.This algorithm considers the calculative time and precision well. The results of the test indicate that this algorithm can both guarantee the accuracy and raise the resolving power in the harmonic analysis without increasing the hardware level and the time of calculation obviously. It can restrain the increasingly serious harmonic pollution in power system effectively.

A transformer is a critical device in an electrical power system substation. Monitoring its condition, including insulation material statuses, is imperative. This article discusses the information modeling techniques of IEC61850 and modeling steps of condition-monitoring IED, analyzes the reporting service, focuses on the characteristics of transformer condition monitoring, rationally develops and makes use of logical nodes and data in the IEC61850 standard, conducts modeling for the actual intelligent electronic device (IED) of transformer condition monitoring and describes the model with substation configuration description language (SCL). The configuration file of this model has passed the test done with standard syntax (Schema mode).