Synthesis and Design of a Variable Structure Controller for a DC Motor Speed Control

C.R. Marcano-Gamero (Venezuela)


Variable Structure Systems, Sliding Modes, Optimization, Simulation.


Main objective of the present work consists in comparing the behavior of a physical plant operated by a VSS against the behavior showed by the same plant operating under control action of a conventional controller, of proportional kind; both of them feedback the integral of the error between the designated reference and the measured value m-file of the controlled variable. Comparison was realized through MATLAB digital simulations. Obtained results confirm a significant diminution of response and settling times, besides an attenuation of the overshoot, which is practically cancelled, due to the commutation between various structures that conforms the VSS, which enforces the system to enter in the so-called Sliding Modes, until it reaches a new operation point. In the synthesis and design process of the VSS used here, basic concepts introduced by V. Utkin were utilized. Furthermore, optimization on a Performance Criterion, due to Krassowsky, was utilized here. This work was done as an academic effort to enrich the plan of studies of the university where the author is working for, in the aim of introducing areas like robotics.

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