| 摘要 |
PURPOSE:To provide an inverter circuit, in which each element of a semiconductor switch group is not damaged even to a DC high-voltage power supply by simple circuit constitution. CONSTITUTION:The upper stage section of a semiconductor switch group 3 outputting the winding currents of a brushless motor is composed of high withstand voltage type P-N-P type transistors Qu1, Qu2, Qu3 and diodes Du1, Du2, Du3, and a lower stage section is constituted of high withstand voltage type N-P-N transistors Qd1, Qd2, Qd3 and diodes Dd1, Dd2, Dd3. A protective circuit is organized of an inductor 7 inserted among the emitters of the high withstand voltage type P-N-P type transistors Qu1, Qu2, Qu3 of the upper stage section and a DC power and a resistor R1 inserted among the bases of the high withstand voltage type P-N-P type transistors Qu1, Qu2, Qu3 of the upper stage section and the DC power. |
