Fractal Control Design with Anti-windup Effect for Optimal Operation of a Power Flyback Source

A flyback source was designed together with a control study which allows its safe voltage range operation. The performance of a fractal PID type control was evaluated, starting from full conditions which allow the controller initialization considering lineal behaviors in a nominal point of operation corresponding to a case study of 2000 W flyback source. To achieve the proposed targets, a non-linear model was developed which reproduces the commuted behavior with the elements necessary to close the control loop. The use of the closed-loop controller took place by implementing an “in series” filtering strategy operated by the controller that avoids overcompensation and control hits, introduced by the fractal derivative prediction. To get a better adjustment on each of the controller effects, an individual fractal index was incorporated for each one of them. The source behavior was evaluated with and without the controller, and the performance of the entire and fractal controller was compared with the same values for the Kp, Ti and Td parameters, demonstrating that the fractal structure is able to improve the operating conditions. The evaluation was carried out with a selected set of static load, and with dynamic tests of both gradual and sudden load variation in time. The capacity of the fractal PID control to correct the deviation during the different tests was demonstrated.