POWER UNIT AND METHOD FOR CONTROLLING ITS OUTPUT

摘要

PROBLEM TO BE SOLVED: To provide a power unit and a method for controlling its output by which the breakdown of a component or load can be prevented surely even when abnormality occurs in a control signal, such as the PWM signal. SOLUTION: When the duty ratio of a PWM signal PWM which is used for controlling the switching operations of a switching element 20 that is switched to impress/non-impress the DC voltage from a DC power source 26 upon the primary winding of a boosting transformer 16 exceeds a prescribed upper limit value, the signal PWM is converted by means of a PWM signal converting circuit 14 and inputted to the switching element 20 so as to lower the duty ratio to the upper limit value or lower.