DRIVE UNIT OF BRUSHLESS DC MOTOR, AND VENTILATION AIR BLOWER MOUNTED WITH IT

• Main Authors: SHIRAISHI MATSUO, ITO HARUMOTO
• Format: Patent
• Language: English
• Published: 04.06.2009
• Subjects: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORSOR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION

PROBLEM TO BE SOLVED: To stably ventilate a brushless DC motor for a long period of time by using a slight wind volume, to surely detect the step-out of the brushless DC motor and stop it even if the brushless DC motor is stepped out and stopped, and to reduce the size and cost of a ventilation air blower mounted with the brushless DC motor. SOLUTION: The ventilation air blower comprises a single-phase induction voltage means 12 and a current detection means 7. A rotor position estimating means 8 can stably be driven even at low-speed rotation by estimating a position of a rotor by using the current detection means 7 when a motor current value is large, and by using the induction voltage detection means 12 when the motor current value is small. An abnormality detection means 11 detects the step-out of the brushless DC motor from a phase difference estimated by the induction voltage means 12 and the current detection means 7, and stops the motor. COPYRIGHT: (C)2009,JPO&INPIT