外文翻譯---plc變頻調(diào)速的網(wǎng)絡(luò)反饋系統(tǒng)的實(shí)現(xiàn)（英文）

1、D. Liu et al. (Eds.): ISNN 2007, Part I, LNCS 4491, pp. 257–266, 2007. © Springer-Verlag Berlin Heidelberg 2007 Realization of Neural Network Inverse System with PLC in Variable Frequency Speed-Regulating System G

2、uohai Liu, Fuliang Wang, Yue Shen, Huawei Zhou, Hongping Jia, and Mei Kang School of Electrical and Information Engineering, JiangSu University Zhenjiang 212013, China ghliu@ujs.edu.cn Abstract. The variable frequency s

3、peed-regulating system which consists of an induction motor and a general inverter, and controlled by PLC is widely used in industrial field. However, for the multivariable, nonlinear and strongly coupled induction mo

4、tor, the control performance is not good enough to meet the needs of speed-regulating. The mathematic model of the variable frequency speed-regulating system in vector control mode is presented and its reversibility h

5、as been proved. By constructing a neural network inverse system and combining it with the variable frequency speed-regulating system, a pseudo-linear system is completed, and then a linear close-loop adjustor is desig

6、ned to get high performance. Using PLC, a neural network inverse system can be realized in actural system. The results of experiments have shown that the performances of variable frequency speed-regulating system can b

7、e improved greatly and the practicability of neural network inverse control was testified. 1 Introduction In recent years, with power electronic technology, microelectronic technology and modern control theory infilt

8、rating into AC electric driving system, inverters have been widely used in speed-regulating of AC motor. The variable frequency speed-regulating system which consists of an induction motor and a general inverter is use

9、d to take the place of DC speed-regulating system. Because of terrible environment and severe disturbance in industrial field, the choice of controller is an important problem. In reference [1][2][3], Neural network i

10、nverse control was realized by using industrial control computer and several data acquisition cards. The advantages of industrial control computer are high computation speed, great memory capacity and good compatibili

11、ty with other software etc. But industrial control computer also has some disadvantages in industrial application such as instability and fallibility and worse communication ability. PLC control system is special desig

12、ned for industrial environment application, and its stability and reliability are good. PLC control system can be easily integrated into field bus control system with the high ability of communication configuration, s

13、o it is wildly used in recent years, and deeply welcomed. Since the system composed of normal inverter and induction motor is a complicated nonlinear system, traditional PID control strategy could not meet the require

14、ment for further control. Therefore, how to enhance control performance of this system is very urgent. Realization of Neural Network Inverse System with PLC 259 strict analytical inverse is very difficult to obtain, ev

15、en impossible. The engineering application of inverse system control doesn’t meet the expectations. As neural network has non-linear approximate ability, especially for nonlinear complexity system, it becomes the powe

16、rful tool to solve the problem. 12 y2dy1dTwo inputsand two outputsnonlinear continuoussystemu1u2y1y2Linearclose-loopcontroller 1Linearclose-loop controller 2th orderinversionANNA pseudo linear systemFig. 2. Compound pseu

17、do linear system control diagram of two inputs and two outputs system th a ?NN inverse system integrated inverse system with non-linear approximate ability of the neural network can avoid the troubles of inverse system m

18、ethod. Then it is possible to apply inverse control method to a complicated non-linear system. th a ?NN inverse system method needs less system information such as the relative order of system, and it is easy to obtain

19、 the inverse model by neural network training. Cascading the NN inverse system with the original system, a pseudo-linear system is completed (Figure 2 is an example of a two inputs and two outputs system). Subsequently

20、, a linear close-loop regulator will be designed. 3 Mathematic Model of Induction Motor Variable Frequency Speed-Regulating System and Its Reversibility Induction motor variable frequency speed-regulating system supp

21、lied by the inverter of tracking current SPWM can be expressed by 5-th order nonlinear model in d-q two-phase rotating coordinate. The model was simplified as a 3-order nonlinear model. If the delay of inverter is neg