基于plc的张力控制系统的发展(英文翻译)

基于plc的张力控制系统的发展(英文翻译)内容摘要：

arying system. Proper simplification of the torque equilibrium equation is carried out with classical control theory based on the following rules: (1) The dry frictional moment and the viscous frictional moment are very little and may be ignored. (2) The influence of J� (t )ω (t ) on the tension force may be ignored since the instantaneous inertia changes very slightly. (3) The scroll radius is realtime measured and fed back by the radius following .(1) is then simplified as TR(t) = M(t) + J (t )ω� (t ) (2) Therefore, the variations of scroll diameter and scroll angular velocity are the main influencing factors of the yarn tension. 3 Compensation of the Radius of the Scroll The radius change of the scroll causes the change of the scroll moment, ., the change of the TR(t ) in Eq.(2). One end of the radius following arm touches the scroll, and the other end is connected to the rotary potentiometer via gear magnifying structure, thus transforming a change in the spindle radius to a change of voltage, as shown in where L is the length of radius following arm, Rmax is the maximum radius of scroll, and R(t ) is the instantaneous scroll radius. Suppose the transmission ratio of the gear is i , then the angle of the small gear is given as φ = iθ For the potentiometer, where U is the output voltage of rotary potentiometer, US is the power supply voltage of rotary potentiometer, and φs is the total angle of rotary potentiometer. Trimmed as 4 Software Development of the System The software development makes full use of the capabilities of FP0C10RS, the digitalanalogy I/O modules, the hardware and software resources of the PC precision of the analogdigital or digital analog conversion depends on the number of bits of the analogdigital converter and digitalanalog converter. FP0A80 and FP0A04V both are 12 bits, and the resolution is 1/4 000 when the output and input range –10V+10V, while the FP0 is 16 bits, so the control resolution of the system can be assured. The operation speed of each basic instruction is μs/step, thus 500 steps program needs only ms, and the conversion speeds of FP0A80 and the FP0A40V both are 1 ms/channel, so the control speed of the system is assured. The PLC ladder diagram is applied to develop the whole control program. However, the input of the parameters is not intuitionistic, neither is the display of the realtime tension and the scroll radius. In order to solve this problem, a control program is developed for the host puter on the interface of which the operator can perform the input of the parameter and the display of the realtime tension, the speed and the scroll radius. The programming port of all the FP PLC’s support OPEN MEWTOCOL PROTOCOL. Upper puter sends a COMMAND to PLC as an ASCLL string. Then the PLC automatically returns the RESPONSE based on the COMMAND. The inputs of the system are the voltage feedback by radius following device, the torque feedback of alternating numeric servoelectromotor and the velocity feedback. The output of the system are alternating numeric servoelectromotor torque。