Fuzzy control logic for switching power supplies and device for performing it

• Main Authors: CUCUCCIO, ANTONINO, LO PRESTI, MATTEO, D'ANGELO, GIUSEPPE
• Format: Patent
• Language: English; French; German
• Published: 03.01.1996
• Edition: 6
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CALCULATING; COMPUTER SYSTEMS BASED ON SPECIFIC COMPUTATIONAL MODELS; COMPUTING; CONTROL OR REGULATING SYSTEMS IN GENERAL; CONTROL OR REGULATION THEREOF; CONTROLLING; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; COUNTING; ELECTRICITY; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; GENERATION; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS ORELEMENTS; PHYSICS; REGULATING; SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES

A process for the fuzzy control of switching power supplies which have at least one inductor and at least one switching device, and a device for performing this control, the particularity whereof resides in the fact that it comprises the following steps: measuring the value of the current (IL) on the inductor (L); measuring the value of the input voltage (Vi) of the switching power supply; measuring an error (E) generated between a reference voltage (VREF) and an output voltage (Vo) of the power supply; defining fuzzy membership functions for the value of the current (IL) on the inductor (L), for the input voltage value (Vi), and for the error (E); defining an output membership function for the value of the duty cycle (DC) of the power supply; defining multiple fuzzy inference rules to which the measured values and the membership functions are applied; calculating the corresponding weight functions of the membership functions; defuzzifying the results obtained by means of the weight function calculation and the application of fuzzy rules so as to obtain a real value of the duty cycle (DC) which is suitable to drive the switching device (SW).