Design Of Coordinated Control System Based On Frequency Conversion

The new type of roving machine has undergone a great change in mechanical structure, systematic transmission and electrical control. It eliminated the up and down cone drums, differential device, rails drive assembly and forming device, which simplified the mechanical architecture a lot. In this design, PLC controlled four frequency converters to separately drive four motors to make flyer, roller, bobbin and rails run in a synchronized way. Thus, the roving machine could product roving of high quality efficiently.Although simplification of mechanical architecture could enhance the performance and the stability of the roving machine in many fields, it became difficult to execute a synchronized control over the four motors of roller, flyer, bobbin and rails in the whole design, which also made the tension control of rove become the key problem to be solved. The core of the design of the new type of machine is how to invent a brand-new control system to substitute the traditional mechanical parts and to realize or even surpass the original functions. Whether this new type of machine can be developed or not just depends on the performance of the tension control.According to the key problems and the most difficulties, this thesis expatiates on the solutions from two aspects, hardware and software. Moreover, it emphasizes on the control system of the tension control in details.In the design of hardware, the thesis gives an overall view on its mechanical design. Then, in the...