| 摘要 |
PURPOSE:To effectively reduce a harmonic wave of a specific frequency by providing a carrier frequency setter for setting an arbitrary carrier frequency and a carrier phase setter for arbitrarily setting a phase of a carrier in a converter control circuit for each of a plurality of PWM converters. CONSTITUTION:A carrier frequency fc is set by a carrier frequency setter 34 of each converter control circuit 30, and phases Q1-Q4 of each carrier are set by a carrier phase setter 35. As a result, each carrier generator 36 generates a carrier of the set frequency fc which is deviated by a set phase Q from a power source frequency input from a synchronous power source 11, and inputs it to a comparator 33. The comparator 33 compares the carrier with a modulated wave Vs', and outputs a converter switching pulse signal which is turned ON only by a time in which the carrier exceeds the wave Vs' to switching elements of allotted converters CONV1-CONV4. |
