Advanced Materials Research Vols. 791-793

Abstract: This paper reports on the optimization of a novel micro-hotplate with three pins designed for micro-structural gas sensor. The temperature distribution of the Si-substrated micro gas sensor was simulated and analyzed by the finite element analysis (FEA) tool ANSYS. In order to make the gas sensor obtain perfect properties of good temperature uniformity, the thickness of Si substrate, thickness of the front and rear SiO₂, measuring electrode width and electrode space were designed to be 150, 50,100, 20 and 500 μm, respectively. The new micro-structural gas sensor is benefit for the improvement of sensor performance.

Abstract: Based on the study of 10 kV digital power distribution network (DPDN) power flow visualization, the paper uses hierarchical backward and forward sweep algorithm (HBAFSA) to significantly shorten the calculation time and improve the real-time performance of power flow, which analysis and layers the distribution network topology according to the breadth-first search and then calculate in parallel between the same level. Programming with Visual C# in Visual Studio 2010 environment gets the GIS data library to actively obtain real-time operating data of distribution network from the SCADA data library, and calculates rapidly with the HBAFSA, and transfers the real-time power flow data to the GIS data library. On the platform of the GIS, clicking nodes and branches can get the visualized real-time power flow, which indicates the achievement of the real-time power flow of the DPDN visualization on the platform of the GIS.

Abstract: The low-voltage distribution system is the key component of the electrical power system. Some analysis and research of the low-voltage distribution system is carried out in this paper, which provides some scientific basis to design the low-voltage distribution system. Firstly, the summarize of low-voltage distribution system is taken. The influence to productions and livings of low-voltage distribution system is introduced. Secondly, the mode of connection and design philosophy of low-voltage distribution system is studied in detail, especially the high-rise buildings low-voltage distribution system is concluded and summarized.

Abstract: nfrared temperature measurement technology is an important means that early detection of equipment external overheating fault and internal insulation fault, and advanced detection methods of power equipment condition monitoring.Infrared temperature measurement technology found the hidden dangers of electrical equipment heating of the external connection points, has been widely applied in power system. With comparing the original ant colony optimization, this paper presents an improved weighted Ant Colony Optimization path planning algorithm based on Infrared image acquisition noise reduction processing and combining WCDMA network transmission mode, and constitute a visual background management system with rural power network .The system could capture power equipment infrared images and reduction noise simply, send it to the background server through the 3G network, for artificial auxiliary to predicting grid failure, scientific planning repair inspection path with improved navigation algorithm, and improve the stability of the power grid operation.

Abstract: The sintered body of tubular cathode for Direct Ethanol Fuel Cell (DEFC) is prepared by the gelcasting process using a certain proportion of graphite powder and mesocarbon microbead (MCMB). The electrical performance under different air flow rates, operating temperature, porosity of cathode diffusion layer, inlet pressure and different thickness of catalyst layer are analyzed by the combination of experimental and numerical simulation method. The results show that the increase of diffusion layer porosity, inlet pressure, thickness of catalyst layer and operating temperature are benefit for the improvement of the cell performance. Moreover, the electrical performance is improved when the air flow rate is 100 mL/min.

Abstract: A new evaluation method of the bridge strengthening effect is proposed based on the fiber optic sensor. The monitor layout scheme of bridge is designed to monitor the bridge strengthening effect accurately by measuring dynamic load moment and transverse vibration of the railroad bridge using the fiber Bragg grating sensor. At first, the paper presents the evaluation principle of the bridge strengthening. And then the fiber sensors are set up on the railroad bridge for extracting data of the health status from these sensors. The effect of the strengthening could be shown from the data change after bridge strengthening applied. The researches provide the scheme of the bridge strengthening quality evaluation, which is the base for the control of construction quality for new bridge strengthening technology.

Abstract: CANopen is a kind of higher layer protocol based on CAN, and it is widely used in industrial automation field, especially in distributed motion control systems. The paper presents an approach of realizing CANopen slave node. Microcontroller STC90C514RD is used as a core chip to design the control system; the design adopts CTM1050 as the CAN transceiver and uses SJA1000 as the CAN controller. And the system consists of a CANopen slave node, input module and output module. MicroCANopen, which is an open source protocol stack of CANopen, is transplanted to main controller so that the function of CANopen could be implemented. Moreover the experimental platform is built to test the design of the system. The results prove that the design is feasible and valid.

Abstract: Dynamic response time is an important performance parameter for capacitive RF-MEMS switch. This paper establishes a differential equation, in order to analyse the influencing factors of dynamic response time. The simulation results show that pulling-down time can reach 7.5μs when beam length equals to 200μm, beam width equals to 30μm, beam thickness equals to 1μm, beam material adopts Al and dielectric layer selects Si₃N₄.

Abstract: Facing the situation that battery life mileage is short and energy efficiency is low, The principle is introduced; control method of energy recovery during the backflow period and of improving the energy recovery efficiency in electronic operation are proposed. On the basis of a 500w switched reluctance motor, the mathematical model of SRM is built. In the model, we use the PWM, APC, and CCC control methods at the same time. The best turn-on angle and the turn-off angle are measured in the light load and heavy load conditions through simulation. The energy efficiency in the heavy load and high speed increases 6 percent; energy efficiency in the heavy load and low speed increases 4.5 percent; energy efficiency in the light load and high speed increases 14.5 percent; energy efficiency in the light load and low speed increases 2 percent. This is instructive to improve the efficiency of energy recovery reduce the cost.

Abstract: Reconditioning is designed to recover the battery on-orbit performance by the most geosynchronous satellites. This paper is to look at post-flight processing of the batteries in spacecraft home and abroad, make comparison and analysis.