Patent ID: 7583039
Filing Date: 2009-09-01
Classification: H02P

Abstract:
1. A sensorless DC motor controller for a sensorless brushless DC motor, comprising: a position-detecting circuit, connecting to the motor, detecting a back-EMF zero crossing point-signal of a rotor of the motor and outputting a position-detecting signal, which is a back-EMF zero crossing position signal according to three-phase voltages of the motor; a current-detecting circuit, connecting to the motor, detecting a line current and generating a current signal; a power supply detecting circuit, connecting to an operating power source, detecting an operating voltage and supplying a voltage transform; a central control circuit, connecting to the position-detecting circuit, current-detecting circuit, and power supply detecting circuit, generating control signals by means of the position-detecting signal, the current signal and a transformed voltage; in which the central control circuit includes: a power drive control circuit, connecting to the central control circuit, receiving control signals and generating high voltage electrical signals by means of the control signals; a motor drive control circuit, connecting to the power drive control circuit and the motor, also connecting to an operating power supply, receiving the high voltage electrical signals and controlling motor running by means of these signals.