| Abstract |
We propose in this paper a real time algorithm developed for machine tools drives. The implementation of this cascade structure based on predictive control laws is possible due to the simplicity of numerical algorithms. A first part will present a polynomial form of the Generalized Predictive Control method, and give a structure of the equivalent linear controller. This approach can provide a real time loop quicker than with a "classical" algorithmic solution. Moreover, this polynomial form allows to study, in frequency domains, the influence of criteria parrameters, on the stability and robustness of the equivalent controller. All this will be shown, reformulating the expression of the control law for a cascade structure. Then a second part will develop and compare the results obtained on two kinds of motors, used as machine-tools drives, with very small sampling period: a brushless motor and a field oriented control induction motor. The advantages of the polynomial predictive cascade control law will be stressed in terms of rapidity, errors cancellations, disturbances rejection and robustness. |
