| 摘要 |
PURPOSE:To reduce the error of torque regardless of the number of revolution by compensating a torque command by power angular frequency in order to cross secondary flux and secondary currents at a right angle including even iron loss currents. CONSTITUTION:A torque compensating arithmetic circuit 10 obtains torque currents IT'' to a torque command T. An iron-loss current arithmetic circuit 12 acquires iron loss currents I0' from iron loss resistance rm. A current- command arithmetic circuit 13 obtains power frequency omega0, a primary-current absolute value ¦I1¦, and a phase angle phi from a torque current command IT' acquired by adding torque currents IT'' and iron loss currents I0', an excitation current command I0', slip frequency omegas, and rotor angular frequency omegar, and obtains each phase current command ia, ib, ic from these values. The output- current feedback control of an inverter 1 by comparison with output currents from the inverter 1 is conducted by a current control amplifier 14 to these current commands ia, ib, ic. |
