Applied Mechanics and Materials Vols. 713-715

Abstract: With the development of digital very large scale integrated circuits (VLSI), how to reduce the power dissipation and improve the operation speed are two aspects among the most concerned fields. Based on sense amplifier technology and bulk-controlled technique, this paper proposes a bulk-controlled sense-amplifier D flip-flop (BCSADFF). Firstly, this flip-flop can change the threshold voltage of the NMOS by inputting control signals from the substrate so as to control the operating current. Secondly, the traditional RS flip-flop composed of two NAND gates is improved to a couple of inverters based on pseudo-PMOS dynamic technology. Therefore, the proposed BCSADFF can both effectively reduce the power dissipation and improve the circuit speed. Thirdly, the designed BCSADFF can work normally with ultra-dynamic voltage scaling from 1.8 V to 0.6V for SMIC 0.18-um standard CMOS process. Lastly, the Hspice simulation result shows that, compared with the traditional sense-amplifier D flip-flop (SADFF), the power dissipation of the BCSADFF is significantly reduced under the same operating conditions. When the power supply voltage is 0.9V, the power dissipation and delay of the SADFF is 6.54uW and 0.386ns while that of the proposed BCSADFF is 2.09uW and 0.237ns.

Abstract: In this paper, an ultra-wideband Wilkinson power divider based on the quarter wavelength transformation is proposed. The proposed power divider utilizes the resonance property of the four stage quarter wavelength microstrip stubs to increase the isolation between the to output ports. As the measured results show that, the power divider has the insertion loss less than 1.3dB with the minimum isolation 15.4dB in the working frequency range from 1GHz to 5GHz. The simulated results and measured results are in good agreement and the proposed power divider can be applied in the communication systems in modern electronic engineering.

Abstract: To analyze response of control system for HVDC during steady-state operation and transient process accurately, an electromagnetic transient model of the actual control system is built based on the platform of RTDS. The rectifier side applies constant current regulator of variable gain, and pole power control/voltage dependent current order limiter. Under the condition of considering no-load DC voltage and nonlinear control design for firing angle, the combination of current regulator and alphamax inverter control is designed. At the same time, transformer tap control on both sides is constructed to match with control of firing angle, including some functions of regulating ideal no-load DC voltage, DC voltage and firing angle. By the analysis of various running conditions and dynamic process, the results show that the model can simulate the characteristics of Ud-Id for HVDC system.

Abstract: Based on PNI11096 magnetic sensor data acquisition system can be used for path recognition of automatic guided vehicle (AGV). The use of the magnetic field on the path to produce paving soft magnetic strip, AGV at run time through the sensor detects the current relative to the magnetic field strength of soft magnetic data will be returned in the STM32 chip data processing after two values through the open collector output 16 bit IO, provide location information for AGV.

Abstract: For forest fire prevention video monitoring data collection requirements,making video data collecting transmission system design based on wireless mesh network;including design standards and principles,design solutions and wireless network video monitoring system design;On the use of standards,working frequency,network infrastructure, coverage solutions,link budget,frequency planning, equipment power supply,supporting transmission and AC design describes the design proposal,proposed overall solution on wireless mesh network digital video system and applied to practical forest fire prevention wireless network video monitoring system,and achieved practical application of research results.

Abstract: It has been proved that Physical-layer Network Coding (PNC) can boost the system throughput obviously and decrease the error rate by reducing the time slots of inter-communication,which makes signal processing efficient and reliable.Coded Modulation (CM) considers coding and modulation as a whole,which makes coding and modulation effective without decreasing system transmission rate ,to guarantee bandwith efficiency.In this paper,the basic idea of the CM and its implementation are introduced.We analyze the effect of the combination of CM and PNC for communication system performance,which provide the foundation for future research.

Abstract: The design scheme for PV system connecting the grid is provided, considering the reactive power compensation, harmonic and lightning effects. Solar power generated connects into the nearby medium and low voltage distribution networks by the inverter. The capacity of solar power total is 1.15MWp. The electricity is generated for personal use; the remaining is connected to the grid system. The scheme is reasonable in design; the system is stable and reliable by the practical testing. It can be used in large range popularization and application.

Abstract: Situation county business system construction is in-depth analyzed in this article. The communication network constraints,lack of standards and operational system is not unified planning are pointed, cannot achieve system integration and sharing of data between departments and efficient coordination office problems. Especially the construction of "Three-Five" new system breaks the pattern of the original business case of rural power management, resulting in multi-disciplinary system efficiency is not high, the accuracy and reliability of system data are reduced and other issues. This paper proposes a stable and efficient communication network in support of the construction of county power production business operations integration platform to achieve business integration applications. The system can provide support services for marketing, production, operations.

Abstract: With the deep and promotion of unattended work in substations, the correct rate of remote signal becomes an important index in automation scheduling system. For remote signal false caused by high-frequency interferences in substation, we propose the use of Ni-Zn ferrite ring to suppress high-frequency interferences. The frequency-impedance characteristics of ferrite ring with different turns are tested. And the inhibitory effect of ferrite ring on interferences below and above 100MHz is measured separately. We installed ferrite rings in remote signal loops, and compared the voltage waveforms before and after installation. Experimental results provide some references to suppress high-frequency interferences by Ni-Zn ferrite ring.

Abstract: Colleges and universities as the important structure of social organization, as well as the large energy structure consumption, it is necessary to analyze the energy consumption characteristics and factors, evaluate the energy-saving potential of college, realize the situation of the energy management system, and then, the energy used in college and economic burden can be reduced based on theory of improving energy management by strengthening energy control management. In this paper, the electrical energy potential saving of consumption in college has been analyzed and evaluated based on data envelopment analysis (DEA) model method. The LonWorks in fieldbus is used in technology field. Finally, the management measures and energy saving methods are proposed.