| 摘要 |
PURPOSE:To compose a driving circuit to be simplified by driving the respective windings of a motor bipolarly with switching elements, according to command speed from DC positive and negative two power sources, and by controlling thyristors in proportion to the command speed, to change the output voltage of the DC positive and negative two power sources. CONSTITUTION:The frequency of the command pulse of an exciting command pulse generating circuit 12 is generated at the phase angle of 90 deg.C of a command speed(f). By an exciting sequence 13, from an inverter driving circuit 11, two- phase rectangular wave voltage having the phase difference of 90 deg.C is fed to the alpha-phase and beta-phase windings of a motor M. At the same time, from a V/f arithmetic circuit 15, the output of phase pulse signal for determining the ignition phase of thyristors SCR1, SCR2 is generated, After that, by a thyristor ignition controlling circuit 16, the phase pulse signal is compared with the zerocross pulse signal of a zerocross detecting circuit 14, and to the respective gates of the thyristors SCR1, SCR2, ignition pulse signals G1, G2 are issued. In other words, output voltage for making the ratio of output voltage V1, V2 to the command speed(f), constant is applied to the motor M. |
