PLC机在复合胎面压出系统中的应用

一、概述 使用PLC机监测与控制,取代以往的显示控制仪表,充分显示出它的可靠性高和抗干扰能力强,并且现场条件要求也不高;使用PLC机控制,简化了电器控制部分,胎面精度可达±5mm（国家标准为±20mm）。另外,PLC机通用性也很好,调试十分方便,编写程序也有很大的灵活性。更换胎面时,可随时修改程序,不影响生产;也可在现场根据实际情况,随时调整、修改程序,以达到最佳工艺效果。 二、硬件结构与软件的合理配合 1.硬件结构 本系统使用欧姆龙PLC机,它的外设结构如图1所示。其中0000为光电传感器的输入口,0100～0115+六个输入口作为预置数BCD码输入口,其他I/O分配在图中均有说明。 2.

Experimental Performance of Moderate and High Temperature Heat Pump Charged with Refrigerant Mixture BY-3

Theoretical and experimental analysis of a new refrigerant mixture BY-3 was conducted based on a single-stage vapor compression refrigeration system. The water-water heat pump system used BY-3 to produce hot water when the low temperature was 20 ℃. The following results were obtained: the highest temperature at the condenser outlet reached about 85 ℃; when the difference between the water temperatures at the condenser outlet and the evaporator inlet was less than 40 ℃, the coefficient of performance (COP) was larger than 4; when the difference reached 55 ℃, the COP still kept 3; the discharge temperature of BY-3 was lower than 100 ℃, and the refrigerant vapor pressure kept lower than 1.8 MPa. When the water temperature at the condenser outlet reached over 85 ℃, nearly a 5 ℃ superheating temperature was maintained.

Flexible Control of Pulsed Power for Biomedical Applications Using PC

This work aims to control pulsed power for biomedical fields, which demands sensitive parameters. The pulsed power consists of a voltage rise time of less than 50 ns and charging energy to 1.0 J/pulse; also, the pulse control area includes pulse interval pulse shot number, output voltage. To achieve this system, a pulsed power system exists including software running on PC, universal serial bus （UgB~ for connection, and FPGA controller. Using the software for complex control of pulsed power will enable expansion into various fields with easy operation.

Norton equivalent circuit for current control loop of grid-connected system

Modeling method for the current control loop of a grid-connected PWM inverter with the LCL output filter was discussed.Firstly,the current control loop with the LCL inverter-side current as feedback was established.Then,parameters of PI controller were calculated on the basis of an equivalent controlled object.Finally,Norton equivalent circuit for the current control loop of grid-connected system was derived by integrating one control equation,which connected the PWM inverter output voltage and the LCL inverter-side current,with two circuit equations,separately using the LCL inverter-side current and the injected current as loop currents.With the induced Norton equivalent circuit,system-level resonant and unstable issues on real grid-connected system applied in weak distributed power systems can be easily analyzed.The validity of substituting Norton equivalent circuit for grid-connected system is verified by simulation and experiment.

The Manuscript Drafting Journey of a NNE Scientific Writer： An Ethnographic Case Study

Given that there is a dramatic increase of the English manuscript submission rate of doctoral students, yet little research effort is devoted to this line, the author investigates the manuscript drafting strategies of one Taiwan Residents hydraulics major doctoral student, who was required by his department to have international publications for the qualifications for the degree. The study employs Ken Hyland＇s social constructionist approach to disciplinary writing and follows an ethnographic research method for the collection/analysis of the data. The results show that the participating student, in order to establish a professional persona for the heightening of manuscript acceptance possibility, followed some prescribed procedures such as citing higher potential journals, adhering to the expert model, and formulizing the research procedures/results. A conflicting rhetorical structure of literature review writing and the favor of doing applied research for publication purpose were also found in his writing. The author addresses the implicated meanings of these writing attempts and concludes that a ＂short-sighted operation＂ of writing attempts may undermine the value of a research. This study contributes to international scientific research communities＇ understanding of this group of writers＇ disciplinary knowledge construction and writing for publication.

Modern Electrical Power Source on New System of Dissipation and Renewable Energies Sources

This paper presents some solutions of modem renewable energy system applied actually in dissipation energy source： wind turbine, solar panel battery charge, SSS （support set system）, and standby diesel generator cooperated in series, parallel and hybrid system with main energy system. Its solution enable obtain independent individual energy source in different work exploitations. One of problems concerned with alternative energy source is changes of output voltages and output power dependence of climatic conditions. Possible solution is application of decoupled adjustable speed generation system in renewable energy generation. The decoupled generation system consists of： alternative energy source, internal combustion engine drives permanent magnet generator and DC/AC, or AC/AC converter. Performance of single decoupled generation set is discussed supported by results of laboratory tests. To provide high quality voltage is applied an additional energy storage, made from super capacitor and bidirectional DC/DC convert. Such system performs very stiff voltage in any load condition. Integration of solar battery panels or renewable wind energy system is provided via DC link of the variable speed decoupled autonomous generation system. Results of computer simulation and laboratory experiments are presented in the paper.

Research on Multi Level Dynamic Voltage Compensator based on MMC

The modular multilevel converter （MMC） is a highly modular, easy to expand; the output voltage waveform is good, especially suitable for application in high voltage power system. This article first introduces the circuit topology and principle of MMC, and the main technical characteristics of MMC. And according to the relationship between the drop power voltage and the load power factor, proposed three working modes of the minimum energy compensation strategy. It is shown that MMC has good application prospect in future medium or high- voltage high power applications, especially be one of candidates for HVDC system application.

A Novel Readout System for Wireless Passive Pressure Sensors

This paper presents a novel readout system for wireless passive pressure sensors based on the inductively coupled inductor and cavity （LC） resonant circuits. The proposed system consists of a reader antenna inductively coupled to the sensor circuit, a readout circuit, and a personal computer （PC） post processing unit. The readout circuit generates a voltage signal representing the sensor＇s capacitance. The frequency of the reader antenna driving signal is a constant, which is equal to the sensor＇s resonant frequency at zero pressure. Based on mechanical and electrical modeling, the pressure sensor design based on the high temperature co-fired ceramic （HTCC） technology is conducted and discussed. The functionality and accuracy of the readout system are tested with a voltage-capacitance measurement system and demonstrated in a realistic pressure measurement environment, so that the overall performance and the feasibility of the readout system are proved.

Theoretical analysis of output speed of multi-pump and multi-motor driving system

A theory for multi-pump and multi-motor hydraulic systems is presented in this paper based on the analysis of the advantages and disadvantages of the popular hydraulic transmission and the double-stator motor(pump).By taking the single-acting fixed displacement multi-pump and multi-motor driving system as an example,the output speeds in a variety of connections of this novel hydraulic transmission are analyzed theoretically.This research work lays a theoretical foundation for the study of the multi-pump and multi-motor driving system and for the design of the system principle diagram.

Self-powered electrochemical anodic oxidation： A new method for preparation of mesoporous Al2O3 without applying electricity

Anodic oxidization （AO） is one of the most important methods available for fabricating mesoporous Al2O3 , which can be conducted at either high potential or low potential; however, the need for an external electricity power source limits its applications. In this work, a novel self-powered electrochemical anodic oxidization （SPAO） system was introduced for preparing mesoporous Al2O3 , by using newly-invented triboelectric nanogenerator （TENG） arrays driven by wind power. Using the controllable voltage output of the TENG arrays, the SPAO system was shown to regulate the pore depth and pore size of the mesoporous Al2O3 . In contrast to traditional AO systems, this technique takes advantage of the high output voltage of TENG arrays without any additional energy costs. In addition, the SPAO system can be used for the preparation of other mesoporous materials.

Design of Linear Sweep Source Based on DDS Used in Readout System for Wireless Passive Pressure Sensor

This paper proposes the design and research on the high bandwidth linear frequency sweep signal source involved in the readout unit module of the wireless passive pressure sensor in high temperature based on the principle of mutual inductance coupling which is applied widely at present. The operating principle of the linear sweep frequency source based on the direct digital frequency synthesis （DDS） technology is introduced, and the implementation method of the hardware circuit and logic sequential control process required in our system has been realized utilizing this technology. Through the experiments under different conditions of the step value, the sweep range and other related design indicators, the influence on the extraction method of resonance frequency information, extraction accuracy, and others during the readout system of the mutual inductance coupling sensor are analyzed and studied. The design of the linear frequency sweep signal source is realized with a resonance frequency change resolution of 6 kHz, a minimum step value of 1 kHz, and a precision of frequency for 0.116 Hz within the sweep width of 1 MHz - 100MHz. Due to the use of the integrated commercial chip, the linear sweep frequency source is made small in size, high working frequency, high resolution and low step values for the readout unit modularized of a higher application value.