Advanced Materials Research Vols. 986-987

Abstract: A new electricity larceny case is proposed in this paper, which using half-wave rectifying method. According to the fact that users consumption varies greatly, analyzing the phenomena discovered and stealing principle. Then simulating the method of electricity larceny in the laboratory, and dissecting the error of the half-wave rectifier stealing mode under different current and power factor. Finally, proposing preventive measures and proposals targeted.

Abstract: The uncertainty contribution related to linearity shall be considered in the calculation of measurement uncertainty when using the impulse voltage measuring system. Under the condition that the national standard is not yet established at present, the paper proposed an experimental method to measure the linearity of 600kV damped capacitive impulse divider (HCR600). The paper used low voltage resistance divider R200S to measure the linearity of generator, and obtained the linearity curve. With the increase of charging voltage, the linearity of divider can be obtained by measuring the charging voltage of impulse voltage generator precisely and its ratio of indicating value of the sample divider HCR600 after corrected. The result shows that the linearity of HCR600 decreases from +0.4% to-0.8%; the maximum difference between positive polarity and negative polarity is 0.14% and the linearity of negative polarity is superior to that of positive polarity. Besides, the paper used a 500kV resistance divider (SMR 7.7/ref500) calibrated by PTB to compare with HCR600, and obtained the linearity curve. By comparison, two curves show a good agreement, the maximum difference between them is 0.15% at the same voltage. The result shows that the method proposed in the paper can be used to measure the linearity of divider accurately. It also can be used as experimental verification in the process of the national standard establishing and to calibrate the ultrahigh voltage impulse voltage measuring equipments when equipments satisfy some requirements.

Abstract: The traditional current transformer measurement device cannot meet the requirements of the rapid development in the current power system because of the outdated structure while the Rogowski coil has significant advantages. This article introduces some applications of Rogowski coil in power system. Now the research and application of Rogowski coil current transformer has become one of the most important research directions. Rogowski coil today has been widely used in electric power system.

Abstract: In view of the current smart meter fee control functions heavy task, work intensity and other issues, we designed a new type of portable smart meter fee control functions test device. The device includes a parallel communication, automatic features such as card issuers, small size, light weight, easy to carry, to achieve automatic control function detects meter fees, enhanced energy meter test bench, between the host computer and the inspector who machine interaction capabilities, improve the detection efficiency of the staff, reducing the misuse rate, and enhance the flexibility of the testing work. The device is able to meet the needs of the current smart meter automatically detects work. Guarantee the accuracy and reliability of the energy meter testing.

Abstract: The fast evolution of computer technology, sensor technology, MEMS and modern wireless communication technology has impelled development of wireless sensor networks. Wireless sensor networks are consist of a large number of nodes which can be capable of communicating, computing and cooperation in ad hoc model. In this paper, we study the application of wireless sensor networks in power engineering. A device for remote monitoring of electric towers is designed. This paper proposes the implementations of remote wireless centralized electricity meter reading based on wireless sensor network.

Abstract: In this paper, A location system for single phase grounded fault in distribution network is proposed and it is based on the phase of zero-sequence current. The system is composed of central station and nodes installed on the power line, and their functions are illustrated in this paper. The principle of the method is shown and experiments are carried out. The results show that the feasibility of the method. The advantage of this method is it’s short time to detect. The method is Applicable to detect the faulty segment for neutral point non-grounded system with grounded resistance less than 1kΩ.

Abstract: The cables in 66 kV and 220 kV systems are used in single-phase style, and it must be grounded between the cables. The connection ways between different lengths of cables are in different ways, thus, it may occur influence to circuit parameters, especially to zero sequence impedance. In order to clarify the situation from theory analysis to calculate impedance under all kinds of connection modes, the paper gives an actual cable measured value, and introduces the correct measuring method, together, points out the matters needing attention in the measurement.

Abstract: When the power transformer in partial discharge test, if the test equipment (voltage regulator, intermediate transformer, etc.) ontology partial discharge is big, it will severely affect the quality of testing, and even cause false identify.How to correctly identify partial discharge from the power transformer or from the test equipment itself, it is very important for the test personnel. This paper introduces to use the idle 220kV circuit breaker in parallel capacitor to cleverly find out in the whole process of partial discharge from the test equipment itself.

Abstract: Great accuracy is required in the settlement process of coal trade. In order to improve the accuracy of coal measurement, a set of online belt weigher calibration device based on the method of material superimposed has been developed. The mechanical structure of the whole device is well designed realizing material circulation conveying. At the same time the software and hardware of calibration system are fully designed.Finally the experimental results indicate that the uncertainty of the calibration device for belt weigher is within 2% and the minimum theoretical ratio of belt material superimposed is about 42% which attains the error requirement of grade 0.5.

Abstract: This paper reviews the research status of vibration environment test equipment and technology. The development of modern vibration measuring sensors, types, processing technology, structure principle and the main performance index of the sensor is made by brief introduction and analysis, the problems existing in the vibration environment test is pointed out, at the same time for their application in the field of modern industry be also made by corresponding introduction.