[雙語(yǔ)翻譯]plc外文翻譯--基于plc變頻控制的加熱系統(tǒng)

1、3100 英文單詞， 英文單詞，15500 英文字符，中文 英文字符，中文 4750 字文獻(xiàn)出處： 文獻(xiàn)出處：Abdallah S, Abu-Mallouh R. Heating systems with PLC and frequency control[J]. Energy Conversion PLC control; Frequency control ;Tempering1. IntroductionHeat treatme

2、nt is the controlled heating and cooling of metals to alter their physical and mechanical properties without changing the product shape. Heat treatment is often associated with increasing the strength of material, but it

3、 can also be used to alter certain manufacturability objectives such as improve machining, improve formability, and restore ductility after a cold working operation. Thus it is a very enabling process that can not only h

4、elp other manufacturing process, but can also improve product performance by increasing strength or other desirable characteristics [1,2].A new single-switch parallel resonant converter for induction heating was introduc

5、ed in [3]. The circuit consists of an input LC- filter, a bridge rectifier and only one controlled power switch. The switch operates in a soft communication mode and serves as a high frequency generator.A voltage-fed res

6、onant LCL inverter with phase shift control was presented in [4]. It was seen that the control strategy offered advantages in the megahertz operating region, where a constant switching frequency is required. The inverter

7、 steady state operation is analyzed using fundamental frequency analyses.A cost-effective high efficiency inverter with phase-shifted pulse modulation scheme was proposed for medium power (5–30) kW induction heating appl

8、ications is discussed in [5]. The proposed inverter accomplishes soft switching operation over a wide power regulation range. The actual power conversion efficiency reached was 96.7%.A control method of reducing the size

9、 of the dc-link capacitors of a converter–inverter system was presented in [6]. The main idea is to utilize the inverter operation status in the current control of the converter. This control strategy is effective in reg

10、ulating the dc-voltage level. Even the dc-link capacitor is arbitrarily small and the load varies abruptly.Chemical composition of hexagonal e-carbide was determined as Fe3C. The effect of particle size and e-carbide/mar

11、tensite orientation relationship on the ?-carbide→cementite transformation was discussed.2. The heating system design and controlIn this work, the design of PLC and frequency controlled heating system were performed usin

12、g an open loop and programming method of control in which stored instructions in memory of PLC was used to control the actuation of heating process. The block diagram of the hardware components of the automatically contr

13、olled heating system is shown in Fig. 1.Fig. 1. Block diagram of PLC and frequency controlled heating system.Fig. 2. Principle circuit of frequency controlled three phase heater.Personal computer is used to write the con

14、trol program then download it to the PLC [19,10] through communication cable. The PLC is S7-200 type, which has 12 inputs, 8 outputs and 220 VAC supply voltage. PLC S7-200 uses ladder logic diagram programming language d

15、escribes in Refs. [19,10]. The PLC main function is to instruct the analog unit to go on or off and to state the required percentage output and the related hold time intervals.The digital output of PLC is ranging from ze

16、ro to 32,700 quantization levels. The analog unit function is to transfer the digital output value at the output of PLC into analog value, which ranging from zero to 10 VDC at the output of analog unit. In the program a