| 摘要 |
<P>PROBLEM TO BE SOLVED: To accurately detect a rotor stop position by a simple constitution in a short time. <P>SOLUTION: Six current-carrying patterns #1 to #6 for making currents flow to three-phase coils are executed in order when detecting the rotor stop position of a brushless motor. The current-carrying pattern #1 makes a current flow to the V-phase coil from the U-phase coil, and a current value of a shunt resistor connected to an inverter circuit is gradually increased when the current-carrying is started. When the current value reaches an overcurrent threshold, the current-carrying is stopped, and a time which has been required for these processes is stored as a current-carrying time T1. When the similar processing is applied to the other current-carrying patterns #2 to #6, the current-carrying times T1 to T6 differ from one another depending on the current-carrying patterns #1 to #6, and thereby the rotor stop position is detected by utilizing this characteristic. <P>COPYRIGHT: (C)2009,JPO&INPIT |
