Advanced Materials Research Vols. 383-390

Abstract: In this paper, a semi-active suspension system has been proposed to improve the ride comfort, and a 2 DOF vehicle system is designed to simulate the actions of vehicle suspension system. The purpose of a suspension system is to support the vehicle body and increase ride comfort. The aim of the work described in the paper was to illustrate the application of fuzzy logic technique to the control of a continuously damping automotive suspension system. The ride comfort is improved by means of the reduction of the body acceleration caused by the car body when road disturbances from smooth road and real road roughness. Based on MATLAB fuzzy control toolbox, fuzzy controller is designed. Simulation analysis of suspension system is preceded by using MATLAB/Simulink7.0. The result shows that this control can improve the body acceleration, suspension distortion etc.

Abstract: For the special requirements of grid-connected inverter used in wind power generation system, a kind of three-phase Z-Source inverter operational principle is analyzed in this paper. Formulas for the design of main parameters under the control of constant duty cycle of shoot-through switching state are derived. Then the simulation models of SVPWM with shoot-through zero vectors are established by using Matlab/Simulink in order to control the switches of Z-Source inverter on and off. The independent control strategy of d-axis and q-axis currents is used to achieve a unity power factor grid-connected aim. Simulation results show that the theoretical analysis and the simulation models are validity.

Abstract: This paper reviews several suitable microvalves for polymerase chain reaction (PCR). First, three type micro-valves in PCR chips are discussed, including pneumatic, servomotor-controlled and passive plug microvalves. Then we present our servomotor-controlled microvalves, with the structure of long passive plug. This valve had many obvious advantages such as simple fabrication and operation, perfect sealing, the ability to withstand relatively high pressure. Furthermore, the microvalve can be operated in a self-actuated mode.

Abstract: In this paper, we propose a modified Waveform Relaxation algorithm to perform large-scale circuit simulation for MOSFET circuits containing lossy coupled transmission lines that have been encountered in modern circuit design community, in which a full time-domain transmission line calculation algorithm based on the Method of Characteristic is adopted. New software techniques are proposed to enhance the robustness as well as efficiency of the simulation process. All proposed methods have been implemented and executed to justify the claimed advantages.

Abstract: The electromagnetic damper studied in this paper belongs to a special kind of coreless generator, which is primarily used for the energy absorption and dissipation in space docking mechanism buffer system. The parameters of magnetic circuit tructure which determines the air-gap flux density are important factors in affecting damping torque. Three-dimensional models are built based on MagNet of Infolytic corporation in this paper. The effects of structure parameters of magnetic circuit such as magnet material, magnetic pole-pairs, rotor thickness on the torque-speed characteristic are researched. The analysis results show that the damping torque is proportional to the square of the amplitude of the fundamental component of the air gap flux density, rotor thickness respectively, the relationship of the torque-speed ratio with the magnetic pole is neither directly proportional nor inversely proportional.

Abstract: Based on SIMPLE algorithm, with the control equation in finite volume method and the SST K- φturbulence model, 3D models of the 1.2MW wind turbine are built to analyze the relationship between the output power and the pressure, velocity and turbulent kinetic energy of its different sections. The results show that: The change of aerodynamic performance which is caused by the interaction of blades and tower , reduces the available torque of the wind turbine that caused the decreases of the output power. The flow field region affected by central swirl and adhesive vortex is very small. The region of velocity field was affected by the wheel and wind turbine, even a few hundred meters away, but the region affected by wind turbine was smaller than by the wheel.

Abstract: Our instruments industry is of some size, initially formed a complete production, scientific research, marketing system. We have more than 6,000 various electronic enterprises, with annual sales of approximately 10 million yuan, have become to Asia's second-largest producer of electronic besides Japan. According to the customs statistics, after complete supporting project introduction, the prize of all kinds of instruments we have imported is nearly 70 billion dollars till 2008, to take up 50% of the total electronic industrial output. But our current electronics industry products mostly on medium lower grade, with the digitalized intelligentized, networked, miniaturized product become the mainstream, the gap will further increase. At present, most of our large-scale instruments and equipments are imported. Foreign products share more than 60% of our market on intermediate products and many key components, whereas homebred analysis instruments share less than two in a thousand of global market.

Abstract: Based on the SIMULINK tool of MATLAB, the paper researches the ship power system, the research includes: load suddenly increased or decreased when one single generator is running, generators’ running in parallel, load suddenly increased or decreased when two generators are running in parallel. Through the analysis of the different work condition, the paper researches the transient stability of the ship power system.

Abstract: A fine system-level calibration technique of size effect error is presented for Fiber-strap-down inertial navigation systems (Fiber-SINS) in this paper. When the strap-down system is mounted onto high precision turntable and rotating along predefined trajectory, the velocity errors can contain information related to the size effect error, which can be estimated accurately by Kalman filter. In this paper, principles of the calibration technique are emphasized, the model of the size effect error is presented and Hardware-in-the-Loop Simulation platform is designed to validate the efficiency of this technique. Results show that the calibration technique has the advantages such as simplicity and high precision. Thus it is of great importance for practical applications.

Abstract: Toroidal motor is a new type of motor. The basic structure of the motor is introduced. Spiral space current in the worm windings is analyzed. The magnetic motive potentials and magnetic linkages produced by two current components are developed. The inductance equations for the toroidal worm windings are deduced. Using these equations, the changes of the winding inductance along with the planet position angle for the drive system are investigated, and the oscillation and the period are discussed. The test of inductance measurement for the motor is done. Test results confirm the validity of the deduced equations. The results offer reference for the dynamic performance analysis and practical application of the novel motor.