| 摘要 |
<P>PROBLEM TO BE SOLVED: To sustain an inverter output at a constant level even when a power supply having a significant voltage variation is employed in a DC power supply of an inverter. <P>SOLUTION: In a conduction control signal generation circuit 20 for an inverter, a difference between an AC output voltage Vo from an inverter circuit 2 and an output from a reference sine wave generator 21 is amplified by an operational amplifier 22. A third harmonic generator 23 generates a third harmonic selected by determining a level with reference to a DC output voltage Vdc of a rectification circuit 1. The third harmonic and the output from the operational amplifier 22 are inputted to an adder 24, and the output from the adder 24 is compared with an output from a triangle wave generator 25 by a comparator 26. The output from the comparator 26 is inputted to a PWM conduction control signal generation circuit 27 and an output therefrom is used for controlling the conduction of a transistor in the inverter circuit 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
