| 摘要 |
<p>PURPOSE:To suppress a malfunction due to an output voltage rise by detecting a cutoff when a power system is cut OFF, and reducing the exciting currents of secondary windings combined in vectors. CONSTITUTION:When a power system is cut OFF, an output voltage VG is abruptly raised. On the other hand, a power regulator 18 and a voltage regulator 19 starts operating in a direction for increasing a torque current component Iq in such a manner that the detected value PL of a feedback value of an effective power control becomes zero, and starts operating in a direction for decreasing a magnetic flux direction current component Id due to an increase in an output voltage VG. Then, when a load cutoff is detected, a flip-flop 20 is set, and a torque current component Iq becomes a set value. Thus, an exciting current is momentarily reduced, and the voltage VG starts falling. Thereafter, the voltage VG is held at a command value by the function of the regulator 19 to continue stable operation.</p> |
