| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor drive circuit capable of economically reducing the switching loss, chopping sound and leak current. SOLUTION: Position detecting means 1 detects a rotor position information, and speed detecting means 2 measures a position detecting interval from the rotor position information. Conducting angle correcting means 3 compares a measured value of the position detecting interval with a target position detecting interval calculates the conduction angle, supplies it as a conduction angle command signal 7 to output phase change-over means 6, calculates time α from the conduction angle to the first commutation timing and time β to the second commutation timing, and supplies them to first and second commutation means 4, 5. The first and the second commutation means 4, 5 output change-over signals, and output phase change-over means 6 generates a drive signal based on change-over signals from the first and the second commutation means 4, 5 and a conduction angle command signal 7. |
