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The harmonics generated by a large number of power electronic equipment in the power grid will seriously affect the measurement accuracy of electric energy measuring instruments. Therefore, in order to determine the anti-harmonic interference performance of electric energy meters, harmonic influence tests are required in the national standards of electric energy meters and the type evaluation outline. As the main standard device used in the harmonic impact test of the electric energy meter, the reference meter has passed the measurement verification, but its verification items do not include the detection of the harmonic measurement performance. In order to ensure the validity of the harmonic impact test of the electric energy meter, it is necessary to test the harmonic measurement performance of the reference meter. This paper designs a set of measurement and detection schemes that uses power comparison method to trace the source of harmonics of reference meters. It has important reference value for improving the accuracy of harmonic measurement and the reliability of electric energy meter type test.

Electric energy is an important source of indispensable for economic-social development and human survival. In order to improve the utilization efficiency of electric energy, more advanced electric energy measurement technology is needed. The main method of electric energy measurement is to measure electric energy through smart meters. This paper uses the overall measurement performance risk assessment method and the dynamic analysis method of in-service smart meters to evaluate the entire system of potential error drift risk of smart meters. It has realized the risk rating for the initial installation of the smart meter, the inaccuracy screening of the smart meter in use, and further provided the full life cycle monitoring program of the smart meter. The research results can accurately realize the remote risk screening and monitoring of the smart meters in full life cycle, save a lot of manpower and material resources, and provide a new path for energy supervision.

Smart energy meters have been widely used in the smart grid of various countries, but the current measurement methods of smart energy meters can not solve the traceability problem under the actual load current and power factor in the process of use, which leads to the inaccuracy of only meters in the field environment, and there is an unknown measurement risk. In order to achieve the accurate on-site verification of smart energy meters in normal working conditions, this paper studies the accuracy of smart energy meter field calibration standard device under different current and power factors, develops the error correction method under non-standard conditions. The correction method adopts the method of establishing reference standard value arrays under non-standard conditions to achieve fast and accurate on-site verification and effective measurement performance evaluation of the smart energy meters in use, to explore the measurement work for on-site calibration of smart energy meters under current and power factor in the actual environment.

As bike-sharing has been emerging, it does not only satisfy people's large amounts of requirements of short distance travel, but also assists in eliminating URBAN ILLS, such as traffic congestion, environment contamination and so on. Its convenience of usage has been greatly promoted when getting rid of parking piles, but some newly situations, such as irregular parking behaviors lead to traffic environmental problems, which has an impact on the sustainable development of the bike-sharing. In this paper, high precision virtual electronic fence technology based on GNSS, intelligent terminal and precision orientation algorithm was proposed. Moreover, the bike-sharing's regular parking management and the accuracy of intelligent scheduling come true via BDS (compatible with GPS s GLONASS and GALILEO). Sub-meter positioning precision was achieved in the virtual electric fence technique, and the accuracy rate of lairaging of the bike-sharing has been more than 90%.

Smart electricity meter are the data bases of monitoring, auditing, counting and analyzing of energy [1]. At present, there are almost 400 million smart meters installed in China, although the meters put into use are qualified, the risk of error drift is still exist in the process of using, which will cause energy monitoring and statistical errors. Based on a large amount of first-check error data of the meters, we proposed a simple and effective method to analyze and evaluate the risk of error drift in the process of using.

In this paper we consider finite-time stabilization problems for networked control systems with state delay and communication delay. The main result provided is a sufficient condition for the design of a state feedback controller which makes the closed loop system finite-tine stable. This sufficient condition is then reduced to a feasibility problem involving linear matrix inequalities. A detailed example is presented to illustrate the proposed methodology.