Advanced Materials Research Vol. 744

Abstract: The extremely low temperature in Antarctic inland area has taken a new challenge for telescope design and develop, the adaptability of components and parts in telescope for the environment close to space. The application of high accuracy encoder is the only way to improve the accuracy of tracking, however, due to the temperature requirement, there is no application of encoder under such a low temperature ever since. To realize the high accuracy of tracking and steering in telescope, high accuracy encoders must be applied in it. Based on the analysis of influence on encoder caused by temperature, an initial thermal control measure is carried out. Secondly, the thermal control measure is optimized with the method that consists of CFD simulations and experiments. Finally, an effective thermal control measure is applied on the second telescope of the 3 Antarctic Schmidt Telescopes (AST3). By the comparison of normal temperature experiment and low temperature experiment, the encoder can reach a temperature of about 25 degrees when it is under the circumstance of-80 degrees after the thermal control works, and the power consumes by the thermal control is less than 6W. The experiment result indicates that the thermal control measure can fit the requirement of temperature that ranges from-10 degrees to 80 degrees and the lowly consuming power requirement, the encoder can reliably work in low temperature with the thermal control measure works.

Abstract: The control system for universal copy manipulator is designed based on combining PLC control technology and Kingview6.55 configuration software technology in this paper.According to the control requirements of control system,the PLC control design of control system and the design of configuration function are elaborated,and the synchronized monitoring of configuration technology for manipulator is also realized.By running test, the design of system structure is reasonable, stable running, and can work good synchronization with actual manipulator.

Abstract: The control strategy of gear-position optimization of an AMT vehicle under Tip-in condition is presented in this article. The down-shift principle of an automatic transmission under an acceleration condition is also analyzed. The in-the-loop simulation platform of transmission system software of an AMT vehicle is established using the Matlab/Simulink. The simulation platform mainly includes the vehicle load module and the control strategy module. The vehicle load module mainly includes the driver intention module, the transmission model, the engine model, the synchronizer model, the clutch model and the resistance model. The hard-acceleration condition is simulated under no deceleration condition by utilizing the optimized control strategy and conventional control strategy respectively. The result indicates that the proposed control strategy can identify a drivers intention, decrease shift times, reduce power interruption time, improve comfort and make the vehicle reach the maximum speed quickly.

Abstract: This paper analyses the active vibration control technology on the piezoelectric ceramics car-body pieces in fuzzy control Strategy. Adaptive controllers, based on fuzzy logics, are synthesized for the control of vibration of body structure. Piezoelectric element, control system and body structure have been combined to be a intelligent response system to external drive and it’s own vibration. This system can effect reducing body structure’s reaction from environmental load with external energy. The availability of the control strategy has been confirmed by experiments.

Abstract: The system had achieved a wireless data communication function using AVR SCM as a control center and basing on radio frequency identification technology. The transmitting terminal of system produces a high frequency signal through capacitance connecting three point type oscillator. And the encoded signal will be transmitted after high-frequency carrier modulated. While after the receiving terminal receive the signal through antenna, and the signal after a series processes including amplification, detection, rectification, voltage comparison will be processed by SCM. The system includes temperature humidity sensor, clock generator chip, photosensitive element, could detect the surrounding environment signal and wireless transmit. The paper elaborates the soft and the hardware realizing specific course of the wireless transmission system. It has an important meaning for the wireless transmission technique.

Abstract: Based on the theory of functional equations in rectilinear embedding, a mathematical model of VLSI placement design was established in this paper. The cell on the plane is conceived as a point, while the wire links the cells is assumed as lines, then the VLSI placement is transformed into quadrangulation by using graph theory. First of all, we obtained generating functions for two types of quadrangulations (quartic graphs) with graph multiple parameters and secondly derived explicit formulae by employing Lagrangian inversion. Furthermore, we found a relation between outerplanar graph and Hamilton graph, and then got the counting result of Hamilton quadrangulation. The quadrangulation calculations could provide a theoretical foundation for computerized algorithm, which can be widely used for VLSI placement optimization.

Abstract: Based on the labVIEW platform, speed measuring system is constructed by using data acquisition card for photoelectric coder. Both method M and T are showed by labVIEW. At the same time, this paper introduces the construction and principle and the implementation of the program of the whole system. The whole system is expanded around data acquisition card, motor driver uses data acquisition card to transmit pulse to drive motor. At the same time, the signal of photoelectric coder converted by transition circuit is received by the different ports of data acquisition card. In terms of hardware, data acquisition card is the core of the system; In terms of software, motor driver, the program of method M and method T are main modules of whole program. The program adopts modular thought to design, and system uses a master module to coordinate the various modules to achieve the desired effect.Keywords: labVIEW; photoelectric coder; speed measuring; data acquisition card.

Abstract: With the rapid development of the smart grid in our country, we need many 10kV smart switches which can protect the safety of the line and complete the reasonable scheduling of the electricity load. In order to realize the reliable power supply for 10kV smart switch, power supply system based on photovoltaic cell technology is designed. In this paper, firstly, we have a brief introduction about the 10kV smart switch. Secondly, composing and principle of the power supply system is introduced. And then, principle of the energy harvesting converter main circuit is analyzed in detail. Then, the MPPT method of the photovoltaic cell based on impedance matching is studied. Test show, the power supply system is suitable for 10kV smart switch measurement and control.

Abstract: Pulse density modulation (PDM) can be used to regulate the output power of the resonant converter. However, in some case of low Q value, the output current is discontinuous and unstable in light load condition which is regulated by PDM. In order to solve this problem, a new Hybrid Pulse Density Modulation method is proposed. The principle of the Hybrid Pulse Density Modulation technique and the control method are analyzed in detail. Through experiments, it is proven that this method not only has the advantages of symmetrical control pulse distribution, smooth and continuous output current, simple control. It also achieves modular design, we can adjust the levels of the inverters output power flexibly through change the number of the basic control module.

Abstract: Nowadays, due to the serious shortage of energy resource, the research and application of new alternative energy has become an important task for each country and government all over the world. In order to protect environment and raise the utilization of marine power, Maritime Environment Protection Committee (MEPC) of International Maritime Organization (IMO) encouraged ship operators to use new alternative energies to reduce marine CO₂ emission. Currently, marine new energy technologies mainly include solar energy, wind energy, waste heat recovery and biological substitute fuel. Wind energy, as a clean and easy getting energy, has been paid a high attention to. This paper mainly introduces the basic features and calculation of wind energy, and then put forwards some shortcomings in the application of it on the ships.