Sliding mode, observer based control, simulation, limitation algorithms
The basic ideas to design discrete algorithms used to calculate unmeasured mechanical or electrical variables, in order to control electrical motors in mechanical systems are presented. The main point of the paper is to simplify the algorithms by using a linear discrete time model without any variable limitations and to reduce the computing capacity requirements of the controller. Limited references, based on the discrete sliding mode for the exception of the influences of variable limitations, are proposed and designed. The main advantage of the controller presented in this paper is that a large control error does not bestow any problems. In such a case, the system always works in an area without the limitations. Original observation algorithms of both position and rotational velocity for exterior permanent magnet synchronous motors are designed. A computer simulation was performed and the results are presented, showing high dynamic accuracy.
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