Control And Research Of Linear Motor Based On The NI CompactRIO

The system, consists of a permanent magnet linear synchronous motor, is widelyused with the rapid development of the AC servo technology.Many kinds of controlmethods are presented to optimize the performance of linear servo system, among them,the robustness is one of the important indexes. Since the sliding mode variable structurecontrol theory has good robustness and fast response, the theory has been widely used inthe servo system. But there are some problems for the traditional sliding mode control inpractical application: chattering problem, control precision problem and constraints of therelative order. Higher sliding mode, which is a further development of traditional slidingmode, not only eliminates the defects of traditional sliding mode, but also keeps itsadvantages.Firstly, this paper researches deeply the mathematical model of permanent magnetlinear synchronous motor, then the basic theory of higher sliding mode and the traditionalsliding mode are introduced, which show the reason why the higher sliding mode canweaken chattering. What’s more, second-order sliding mode control and severalalgorithms are mainly introduced. A tracking-differentiator control based on second-ordersliding mode is proposed permanent magnet linear synchronous motor servo systemwhich is easily influenced by time-varying disturbance, load disturbances, parameterschanged and so on. The speed controller of the linear motor system which used thesecond-order sliding mode control can effectively compensate and weaken chatteringand improve the fast tracking performance. The tracking differentiator control which isused to estimate the required acceleration signal can ensure mover speed track itsreference signal strictly when the parameter change or resistance to disturbances of themotor. This paper builds a simulation system in the LabVIEW environment,the simulations indicate that the control scheme can enhance the track-command-ability,improve the robustness for the parameter variations and time-varying perturbation, andsuppress the chattering obviously. The system can obtain the good and dynamic staticperformance.Finally, hardware test platform is implemented with the controller of NICompactRIO, software program is written on the LabVIEW、LabVIEW FPGA moduleand RT module. After the test, the system can obtain the good dynamic and static performance, it proves that the algorithm is effective.