Advanced Materials Research Vols. 986-987

Abstract: With the Wide Area Measurement applications, a large number of experimental PMU data was generated. In order to analyze, transmit and apply the data efficiently, by understanding the characteristics of the PMU data in this paper, pressing the data with the Waveform difference method, then using Huffman algorithm to compress the data. Compare the data pre-processing before and after, compression ratio has been further improved.

Abstract: in view of the substation equipment temperature measuring work, the existence of low accuracy of temperature measurement, data real-time performance, large work volume on manual operation, the temperature of the wireless sensor monitoring technique, the 2.4 GHZ wireless network technology, build a wireless temperature monitoring system, substation equipment temperature and the temperature rise of accurate, reliable and real-time on-line monitoring. Real-time monitoring data, intuitive display are in tabular and graphical form. Have the equipment temperature measurement data, temperature change trend analysis, data query and management, over temperature alarm to remind, etc. Real-time temperature data can be convenient access to the substation set control center, to ensure safe and reliable operation of the transformer substation, for substation monitoring and maintenance of equipment operation to provide data support, effectively prevent substation equipment oxidation, burning and other accidents.

Abstract: This paper aims to detect cracks on the rail head via eddy current and show their locations. The combination with mechanical and electronic devices is approached by modeling and analysis. Based on eddy current technology, voltage difference replaces phase shift and the amplification is gained by a triode differential amplifier. It realizes inspection of cracks. Being operated with an incremental optical encoder, Peripheral Interface Controllers and the Liquid Crystal Display, the distance measurement module records the defects. It is applied with a small section of rail tracks.

Abstract: Expensive special equipments are often employed to evaluate the performance of low voltage battery, because of the loss voltage of test terminal and line. In the present paper, an economic method was proposed to evaluate fuel cell performance using the booster power supply and electronic load with remote sense. The testing method was deduced theoretically and applied to study the performance of the direct methanol fuel cell . According to the results, it was found that the method was economic applicable and feasible.

Abstract: In order to reduce the charging time and improve the charging efficiency, designed a kind of intelligent charger on the base of existing charging methods by stages after analyzing the advantages and disadvantages of the domestic quick charge of the storage battery. This system uses STC89C52 as the controller, adding the function of trickle charge and the ability to prevent reverse polarity. It has extended the working life of storage battery a lot.

Abstract: In this paper, a new chaotic system is constructed. This system contains four parameters and two nonlinear terms. The fractal dimension and the heteroclinic orbit are analyzed in the system. Meanwhile, the circuit of the chaotic system is designed by using Mutisim software. The conclusion confirms the consistency of the numerical simulation and circuit. Because of the above properties, the proposed system has a wide application in such as weak signal detection secure communications and secure communications.

Abstract: An optoelectronic oscillator (OEO) based on series-coupled double recirculating delay lines (SC-DRDLs) is analyzed and experimentally demonstrated. The SC-DRDLs composed by the coupling cascade of two RDLs, which the free spectral range (FSR) is least common multiple of the two RDLs’ FSR, and then the large FSR can be obtained by properly setting the loop lengths of two RDLs. By consociation with the dual loops system between the dual output of the SC-DRDLs and PBS, the high sidemode suppression performance can be achieved. Meantime, the incoherence of the SC-DRDLs can be performed by using an amplified spontaneous emission (ASE) broadband laser source. An experiment is carried out. A microwave signal with high spectral purity, long-term stability, low single-sideband (SSB) phase noise is generated.

Abstract: A sense amplifier applied for low voltage embedded flash memories is presented. The sense amplifier uses an enhanced current sensing method allowing power supplies lower than 1.5 V to be used. The sense amplifier was implemented in a FLASH realized with a 0.13 um FLASH technology. Simulation results showed a read access time of about 25 ns with a power supply of 1.5 V, and 32ns with a power supply of 1.2V.

Abstract: In order to get a stable source line voltage, a novel source line voltage compensation circuit has been designed to compensate the IR drop on the source line decoding path. The circuit is verified in 0.18um flash memory technology.

Abstract: A voltage regulator circuit for low power flash memories is presented. The voltage regulator circuit was implemented in a flash chip realized with a 0.18 um flash technology. Experimental results show that standby current is less than 0.3 μA at 1.8 V and 25 °C.