Power supply system, controller therefor, and method of manufacture of controller

Abstract

A power supply system of the present invention aims to achieve optimization of the efficiency and therefore includes: z (z is a natural number equal to or larger than 2) power supplies (PS-to PS-z) connected in parallel; and a controller () for the number of power supplies in operation which controls the number of power supplies in operation among the power supplies (PS-to PS-z). The controller () for the number of power supplies in operation determines the number of the power supplies in operation based on values of intersection currents ito iwhich are determined through processes of: identifying output loss characteristics with respect to load currents of the z power supplies (PS-to PS-z) by use of convex functions fto fz, respectively; obtaining a function hexpressing a conversion efficiency of a total load current at the time of operating the n (n is a natural number equal to or smaller than z) power supplies (PS-to PS-z) based on the functions fto fz; and obtaining an intersection current i(q is a natural number equal to or smaller than (z−1)) which is a current of an intersection point between a function hand a function h. (Greek letter eta is replaced with h.)