PWM SIGNAL GENERATING CIRCUIT, SYSTEM INTERLOCKING INVERTER SYSTEM EQUIPPED WITH THE PWM SIGNAL GENERATING CIRCUIT AND PROGRAM FOR ACHIEVING THE PWM SIGNAL GENERATING CIRCUIT

PROBLEM TO BE SOLVED: To provide a PWM signal generating circuit for controlling a voltage step-up circuit so as to prevent the occurrence of switching loss when a voltage step-up level is low. SOLUTION: The PWM signal generating circuit 6 generates a signal for PWM-controlling a voltage step-up circuit 3 for stepping up voltage of DC power. The PWM signal generating circuit includes: a carrier frequency determining means 65 for determining a carrier frequency from an input voltage input into a voltage step-up converter circuit 3 and an output voltage output from the voltage step-up converter circuit 3; a carrier signal generating means 66 for generating a carrier signal of the carrier frequency determined by the carrier frequency determining means 65; command value signal generating means 62, 63, 64 for generating command value signals based on the input voltage or the input current to be input into the voltage step-up converter circuit 3; and a pulse signal generating means 68 for generating a pulse signal from the carrier signal and the command value signals. COPYRIGHT: (C)2009,JPO&INPIT