| 摘要 |
PURPOSE:To accurately detect a rotor position by delaying 90 deg. in the phase of 3-phase induced voltages of armature windings, and obtaining a difference from a value divided by a resistor and combined in other two phases for each phase, and driving a switching element. CONSTITUTION:3-Phase AC obtained by driving a semiconductor commutator unit 1 made of six semiconductor switching elements Q1-Q6 by a DC power source E are supplied to armature windings 3 to rotate a magnet rotor 4. In duced electromotive forces 8U-8W generated at the windings 3 at that time are delayed at 90 deg. of phase by signal converting means 6 as signals 9U-9W. The values divided by two resistors 11 into the signals 9U and 9V, 9W are compared by a comparator 7 to obtain a signal 10U. Similarly, signals 10V, 10W are obtained from the signals 9V, 9W. The signals 10U-10W are input to control means 5, and the conduction angles of switching elements Q1-Q6 are controlled. Thus, even if the armature windings 3 are irregular, a rotor position can be accurately detected by a simple circuit to perform a stable operation. |
