| 摘要 |
PROBLEM TO BE SOLVED: To omit a capacitor at rectifying part by preventing the increase of iron loss, and to elevate the higher harmonic properties. SOLUTION: This device has a coordinate converter 51, which outputs a d-axis detection current and a q-axis detection current, based on a u-phase current iu, a w-phase current iw, and a motor's rotational angle θe, a generator which generates the phase of power voltage, an operator 53 which generates a q-axis current command from the phase generated, a d-axis current command generator 54, a q-axis proportional controller 55 which computes a d-axis voltage command, a controller 56 which computes a d-axis voltage command from the d-axis current command and the d-axis detection current, a calculation section 57 which calculates the voltage amplitude from the output from the controller 55 and the output from the controller 56, an operator 58 which calculates the voltage phase from the output of the controller 55 and the output of the controller 56, an operator 59 which calculates the modulation rate, an operator 60 which calculates the pulse width from the sum of the motor's rotational angle and the voltage phase and the modulation rate, and a timer 61 where the pulse width is set. |
