Switch-mode power supply, has pulse-width modulator and phase regulator combined into unit for controlling actuator for switching primary winding current of transformer

摘要

The power supply includes a pulse-width modulator (7) controlling an actuator (6), such as a power semiconductor switch for switching current through the primary winding (5) of a transformer (2) A phase regulator (8) controls the input current so as to be the same phase as the input voltage. The pulse-width modulator and phase regulator are combined in a drive circuit unit (7,8). This drive circuit controls the actuator for switching the primary winding current.