Applied Mechanics and Materials Vols. 713-715

Abstract: In order to study the interaction effect between three buoys of wave power platform of "Haiyuan 1", we’ve made a research to that wave power platform in real sea conditions. We tested respectively the motion curve of different buoys, calculated the average delivered power, and analyze the interaction effect of buoys. We hope that the experimental result can provide technical support for the arrangement of wave power platform buoy.

Abstract: There are many various patterns for electricity market. Different countries adopt different patterns according to their own characteristics. However, no matter what pattern they adopt, there must be a certain structure similar to long-term market and real-time market where power sellers usually make electricity transaction. From the view of electricity power sellers, it is the key for hydropower enterprise (Power seller) to find an optimal sale strategy which can maximize the amount of electricity sale while minimizing the probability of risk. In this paper, on the base of analysis on the deterministic gross generation, a mathematic model is established to gain the maximal income of electricity sale in the case of considering risk factors, and to investigate the relationship between risk factors and electricity sale distribution in the two markets, long-term market and real-time market. Then, subsequently, the optimal strategy of electricity sale distribution of gross generation will be obtained in every market in order to maximize the total expected benefit. The feasibility and validness of the Model are verified by its application to a case as well.

Abstract: A large amount of elevators ruined in seismic events since sudden vibrations are bursting when elevator’s cars or counterweights are running. To solve this practical problem, this paper prospered a seismic sensor system with MEMS technology specializing for elevators. The fatal parts are discussed detailed including hardware design consideration, software improvement of sensor accuracy and seismic evaluation algorithm. Finally, two parts of experiments about P-wave and S-wave were verified successfully. To some extents, it’s reliable, suitable and affordable for domestic elevator’s safety on earthquake abrupt occurrence.

Abstract: A quantum computer is the computer technology and the micro physical scientists will combine the technology achievements. Quantum computer is the processing of information by using the quantum properties of particle, a new concept quantum laws to control information transmission and processing of computer. Light has the advantages in space time parallel and high-frequency radiation, which makes the optical become the main target of research model the future of computers. This did not prevent the three valued logic calculus is still an important part of the three values of optical computer. It is precisely because the three value of optical code decoder and the three value, importance, ALU logic optical so, in three valued optical computer all the key parts, we firstly research the value of three logic optical light coding, decoder and a value of three.

Abstract: The effective control of a grid-connected inverter (GCI) under unbalanced grid voltages condition is able to enhance the grid-connected operation ability of the inverter. This paper studies the control scheme of a three-phase GCI with proportional plus resonant (PR) regulators in the stationary αβ frame to remove the power ripples caused by the unbalanced condition and the currents of positive and negative components can be controlled directly without any decomposition. A precise and fast phase locked loop is also introduced in this paper. Three control targets are achieved on a 2KVA experimental platform of a GCI and the experimental results agree well with the theoretical analysis.

Abstract: 3.3kV and 4.5kV 4H-SiC junction barrier Schottky (JBS) diodes with floating guard rings edge termination have been fabricated. The 3.3kV device with 33μm 2.7E15 cm^-3 epilayer and 5.5Х5.5mm² schottky contact area has a blocking voltage (V_b ) of 3.9 kV and a specificon-resistance (Ron) of 10.5 mΩ.cm², with a forward current measured up to 50A at V_F=3.0V. The 4.5kV device with 50 um 1.2E15 cm^-3 epilayer and 5.5Х5.5mm² schottky contact area has a blocking voltage (V_b ) of 5.1 kV and a specificon-resistance (Ron) of 22.9 mΩ.cm², with a forward current of 30A at V_F=3.7V.

Abstract: The steady-state mathematical model of Smith-connection three-winding single-phase capacitor motor is established, and the capacitance calculation formula in minimum voltage unbalance condition is deduce .Based on this, by MATLAB simulated program, a operation simulation of Smith single phase capacitor motor that in single-phase 220V power supply and in single-phase 380V power supply is developed. The simulation results agree with the experimental results.

Abstract: This paper introduces the working principle and structure of direct digital frequency synthesizer. This paper select the technology of lookup table to design DDS because it has many advantages such as less consumption hardware resources, simple structure, output only small delay and so on. As a result, signal generator can produce many waveforms with good stability and high frequency resolution. Finally, test showed that the output wave of triangular signal frequency is greater than 1MHz and the highest sine wave frequency is 30MHz, the value of peak to peak is continuously adjustable in 50mV ~ 4V range. The result of study will provide theoretical guidance for the design of DDS.

Abstract: 1200V-15A 4H-SiC junction barrier schottky (JBS) diodes were designed and fabricated based on SiC epitaxy and device technology. By adopting the proper SBD metal,optimized structures and fabrication process, we succeeded in achieving good balance between blocking voltage and on-resistance, especially at high temperature to 200°C. Furthermore, the fabricated diode have a fast recovery time of 30ns, and its dynamic characteristics are constant at high temperature.

Abstract: According to the application of the high voltage SiC devices, studying the package of three kinds of SiC dies with different metals. Experiments show that all die wire bonding and shear strength measurement up to standard, and provide three kinds of packages for different applications, at the same time, filling the needs of producing. The purpose of the shear strength test is to determine the integrity of materials used to attach SiC die to package substrates.