Applied Mechanics and Materials Vols. 427-429

Abstract: This paper implements a 5 bit to 6 bit reconfigurable delay line ADC implemented with changing the length of delay line for digital DC-DC. The comparator, 33 delay cells and the decoder of the ADC is shared to reduce the area and power when this ADC works and changes accuracy. A detect and control logic is designed to change the input offset current of every delay cell to protect the delay line work correctly when the accuracy of ADC is reconstructed. Circuit performance is analyzed theoretically and simulated under CSMC 0.5um process. This paper designs a window delay line ADC whose voltage sensing range is 1.352V to 1.448V, LSB is 3mV or 1.5mV and sampling frequency is 4Mhz.

Abstract: To decrease the cost brought by the electric energy waste, a three-phase equilibrium distribution soft-switching system is proposed. The system guarantees three-phase equilibrium. Firstly, the inverter tracks the original access phase to be synchronous, then switch the electric equipment to the inverter. Secondly, the inverter tracks the alternative access phase to be synchronous, then switch the electric equipment to the alternative access phase to accomplish the soft-switching. Experiment is used to carry out verification for this system. The result shows that there is no impulse current when the electric equipment switches. The system achieves soft-switching.

Abstract: The ultrasonic flowmeter designed in this paper uses improved time difference method to measure the flow velocity, uses MSP430 as microprocessor. The flow velocity measurement equipment of the ultrasonic flowmeter is based on CPLD(EPM7064AE). The results of the experiments show that the ultrasonic flowmeter has many advantages such as low starting flow, small pressure loss, low consume, operation reliable, fully functional and so on. It has good potential application of market.

Abstract: A novel type AC-AC converter based on the switched-capacitor principle is presented. The circuit topology of the switched-capacitor converter, the principle of operation, the equivalent circuit model and an example are described in this paper. In order to demonstrate the performance of this converter in the laboratory, this paper designs a prototype of 600W, 220V high-side voltage, 55V low-side voltage and switching frequency of 50 kHz. The experimental results verify the validity of the theoretical analysis.

Abstract: For a coherent DDS/FFH system (deeply direct sequence and coherent fast frequency hopping hybrid spread spectrum system), signal has a very large spread spectrum ratio. Signal acquisition process becomes very complex and difficult due to interference and doppler frequency shift in a strong interfering and high dynamical environment. FFT corelation sequence points are very large if traditional frequency-based FFT acquisition scheme is used, FFH requires FFT operation should be completed in a much shorter time (within one hopping duration time), which makes system realization become very complex or even impossible. A partial matched filter combining FFT, coherent accumulation combining incoherent accumulation acquisition scheme is investigated, system realization complexity is reduced.

Abstract: Based on the disadvantages and problems of current detect ways, come up the testing system which using numerical controlled oscillator (NOC), Digital Radio Frequency Memory (DRFM) and digital down-covert to intermediate frequency (IF) processing, introduce the background information, main functions, total structure and design implementation.

Abstract: This article analyze the transmitting characteristics of information in the modern And than, we find the basic design criterion of fault detection system in the complicated electronic devices. Than we discuss the possibility of achieving fault detection through a communication protocol. So we describe the design project of achieving detecting fault function through the communication protocol. At last, we brief introduce simulative detection function about fault detection circuit.

Abstract: Average consensus is studied in mean square sense of distributed inference in a sensor network under Markov communication topology of uncertain transition probability. A sufficient condition is presented for average consensus. Based on linear matrix inequalities and numerical optimization, a design method is provided of faster distributed inference systems.

Abstract: In this note, the consensus problem of linear multi-agent systems with Markovian communication topology and time-varying delay is investigated. The topology of network is switched by Markovian process and the time-delay is considered to be time-varying and has a lower and upper bounds. A sufficient condition of mean square consensus is obtained in terms of linear matrix inequalities, and based on the condition, a controller design method is presented such that the multi-agent systems reaches to mean square consensus.

Abstract: The spectrometer is a basic tool of optical measurement, having a wide application field. Because of its small visual range and used in a dark environment, traditional spectrometer cause eye fatigue, inconvenient in reading figure and its utilization rate is low. In order to solve these problems, I utilize Xilinx FPGA and CCD to retrofit the traditional spectrometer. Making the image which in the eyepiece shown on the displayer, realize the goal of Digital Angle measurement. The new design spectrometer has the advantage of operate simply, convenient maintenance, etc.