| 摘要 |
PROBLEM TO BE SOLVED: To provide a driving device for which an excitation circuit is not required, as means for driving a synchronous motor including an excitation winding.SOLUTION: A driving circuit 100A includes: an inverter 110 which generates a three-phase AC voltage to be given to three-phase armature winding of a synchronous motor 10 by switching a DC voltage V1 between a high-potential power supply line 113P and a low-potential power supply line 113N; and a capacitor 140 which is interposed between a neutral point 3Q of three-phase armature winding 3U, 3V and 3W star-connected in the synchronous motor 10 and the low-potential power supply line 113N and connected in parallel with excitation winding 5. The capacitor 140 is charged with a 1/2 DC voltage of a DC power supply voltage between the high-potential power supply line and the low-potential power supply line, the charging voltage is applied to the excitation winding 5, and an excitation current flows to the excitation winding 5.SELECTED DRAWING: Figure 1 |
