| 摘要 |
PROBLEM TO BE SOLVED: To reduce a beat phenomenon of a phase current when an inverter operates in control mode of 1 pulse mode by comparing a DC link voltage time product to a DC voltage link time product reference and by controlling a gate of switching element constituting an inverter. SOLUTION: A DC link voltage Vd applied to a DC capacitor 3 is detected by a voltage detector 7, this detected current link voltage Vd is integrated by an integrator 7, and a time product Vd T of the link voltage is obtained. A DC link voltage reference voltage Vd * is divided by an inverter frequency reference f1 *, and a time product reference Vd T* of a DC link voltage is calculated. Then, inside a gate controller 12, the DC link voltage time product Vd T is compared to the DC time product reference Vd T*, a switching state is determined, a gate of a switching element constituting an inverter 4 is controlled, and the mean value of each phase current value of the inverter 4 is controlled to a constant value. |
