| 摘要 |
PURPOSE:To enable the pulse width of a switching element to be set shortest by comparing an output of a function generator fed with an electrical angle command value of an output voltage as an input and an output of an integrator by F/V command making the integrated amount variable. CONSTITUTION:The output of the function generator 2 fed the electrical angle command value of the output voltage and the output of the integrator 5 through a switch 4 fed the F/V command are compared by the comparator 6, and the output of the comparator is fed to a latching circuit 7 latched each time when pulses in a clock frequency fC being fed, to obtain PWM output wave form. Further, the output of the latching circuit 7 is fed to the switch 4 to control the integrator 5 and subject to follow the output of the function generator 2 in lagging by one pulse in the maximum clock frequency fC. Accordingly, since the shortest pulse width is decided depending on the clock frequency and the PWM is made by pulses alone in larger widths than that, influences on the main circuit switch can be arrested. |
