| 摘要 |
PURPOSE:To prevent the lowering of voltage applied to a motor in a low sped region, and to obviate the reduction of torque by correcting an inverter output- voltage command signal on the basis of the inner voltage drop of an inverter and a voltage drop by a motor wire-wound resistor and a wiring resistor. CONSTITUTION:Output currents from an inverter are detected by a current detector 9, the magnitude I1 of currents is arithmetically operated in a current absolute-value computing element 10, and the magnitude It of a current compo nent orthogonal in a vectorial manner to exciting currents is arithmetically operated and detected on the basis of I1 and an exciting-current reference value Im* in a current-component computing element 11. The wire-wound resistance drop of a motor and the inner voltage drop of the inverter are arithmetically operated on the basis of It and Im* in a voltage-command computing element 3, thus changing a voltage command V*. |
