CONTROL ÓPTIMO DE LA VELOCIDAD DE MOTORES DE INDUCCIÓN QUE MINIMIZA PÉRDIDAS DE ENERGÍA ELÉCTRICA Y TIEMPO DE CONTROL

Abstract

In his thesis, we will the design of optimal control of the of induction motors speed that minimize the electric energy losses and time control, limiting the amplitude the supply current to a desired value. For optimal control synthesis that limits the amplitude of the stator current while minimizing the electric energy losses in the windings of the stator and rotor (electrical loss) in the magnetic core of the motor (magnetic losses) and the time control are used: the induction motor model that considers the electromagnetic transients and saturation of the magnetic material of the motor, the optimization method of Pontryagin maximum principle and the hybrid algorithm of parametric optimization. Due to the optimization problem discussed in this paper multi-objective accepted as the index of optimization the linear combination of the singular criteria (formulated to minimize separately the magnetic losses, electrical losses and time control), multiplied by the weight coefficients1,2,3 , the solution of the problem dual boundary value must be repeated for each of the chosen combinations of weight ratios mentioned. After obtaining the results for each of the combinations used are selected optimal solutions or no dominated solutions. In the case of simultaneous minimization of total losses and the time control is usually obtained over a non-dominated solution, and then you have to choose one solution guided by the relationship between total losses and time control. This control is applied at the idle starting for three induction motors of different power: 3 H.P., 500 H.P. and 2250 H.P.. With the results of the simulations, we obtain conclusions about the controls designed. The optimal control that minimizes electric energy losses (electric losses and magnetic losses) and time control has a well performance properly within little limitations of the current amplitude of the stator, this ensure not to have magnetic saturation into the iron core, but from the optimization point of view, an undesirable long time control is presented. In the case of great limitations the stator current amplitude is not guaranteed that the motor into saturation however the time of control is short. . The programs that were used in the simulation realized in FORTRAN 90 (algorithm of parametric optimization and simulation program of optimal starting).