Applied Mechanics and Materials Vol. 389

Abstract: The state overhaul is not only a kind of maintenance system, but also a kind of management system, which is especially important and widely used in power system. However, in recent years, along with the power system in large-scale development of high parameters and automation, only relying on the traditional sate maintenance already cannot satisfy the power system safe and stable operation requirements, and the emergence of the state overhaul based on Internet of things technology can well solve the problem. After the review of the application of state overhaul in power system based on Internet of things technology in this paper, emphatically expounds the applications of state overhaul based on Internet of things technology in power plants, transmission and substation equipment. Pointed out that state overhaul based on Internet of things technology is the key to realize the fusion between smart grid and IOT . Finally, make outlook the related research of state overhaul in power system based on Internet of things technology.

Abstract: The second-order nonlinear optical effect in asymmetric quantum wells is investigated. By using compact density-matrix approach, the analytical expression of the second-order nonlinear optical coefficient is obtained. The results show that the second-order nonlinear optical coefficient increases with the increasing of the asymmetry of quantum well. In addition, the nonlinear optical coefficient which obtained in this asymmetric quantum well is very larger than that obtained in bulk GaAs.

Abstract: The randomness of electrostatic discharge current waveform is considered to present great problems in experimental data analysis and drawing conclusions. In order to solve this problem, we measured a large amount of data in electrostatic discharge experiments. The experimental data are studied by statistical methods and new parameters of waveform dispersion, the waveform error within group (E_w) and the waveform error between groups (E_b), are defined in this paper. And peak current, rise time, 30ns current, 60ns current are also analyzed. The results indicate that statistical analysis plays an important role in the experimental study of electrostatic discharge and the parameter variations of contact discharge equivalent circuit might be an important factor of the randomness of electrostatic discharge current waveform.

Abstract: t focuses on the test and analysis of running conditions for the air conditioner and the functional segments at all levels in this paper, backed by the direct evaporative cooling air conditioning units experiment table. Analyze the influence of inlet air dry ball temperature and relative humidity to air conditioner cooling capacity and cooling efficiency, which has certain guiding significance to improve the direct evaporative cooling air conditioner performance.

Abstract: As one of the most applicable to high-voltage network superconducting fault current limiterSCFCL(saturated core superconducting fault current limiter) ,which use of core saturation properties can be achieved the current-limiting function without delay ,will be the most widely applied in the future,By analyzing the working principle of SCFCL,this paper use of PSCAD and finite element analysis software Ansoft to build the 500kV\/3150A grade SCFCL model and accurate calculation coil self-inductance and mutual inductance, the harmonic of each size and analyzed its Impedance characteristic on the different external parameters,The results show that SCFCL has a excellent performance for high voltage power network short-circuit current limitation, and provides important reference for design.

Abstract: The submitted paper deals with an analysis of geometric deviations, reasons of their generation and provides their brief description. It points at ways and abilities of measuring shape deviations by means of contact and contactless measuring methods and deals with errors which can affect results of measuring. The papers also says about practical measuring geometrical deviations by commonly used tools. It evaluates and analyses ability of measuring by various devices. It shows a review of individual measured values and thus provides a view of efficiency, simplicity and accuracy of individual measuring methods and measuring devices.

Abstract: The power transformer is the most important equipment in the power system, so the condition-based maintenance of the transformer has an important significance for the safe and stable operation of the power grid, and condition assessment provides an important basis for the condition-based maintenance. In this paper, the calculation principle of the reliability assessment method is analyzed, and the contribution of each feature value is calculated. It has an important guiding significance for the Power Supply Bureau to provide the condition assessment data, the data with a contribution of large degree should be collected forcibly, so that the data for transformer reliability assessment is the most simplified, improving the assessment rate.