Sensorless BLDC motor systems and driving methods of sensorless BLDC motor

摘要

Provided is a sensorless BLDC motor system. The sensorless BLDC motor system includes a BLDC motor, a comparator, a motor controller, a three-phase inverter, and a mode selector. The BLDC motor includes first to third coils. The comparator compares a voltage of a specific coil of the first to third coils with a neutral-point voltage to output the compared result. The voltage of the specific coil becomes equal to the neutral-point voltage and a specific time elapses, and then the motor controller generates first and second coil control signals based on the compared result. The three-phase inverter supplies a source voltage or ground voltage to the specific coil, or floats the specific coil, in response to the first and second coil control signals. The mode selector selects a driving mode of the BLDC motor by adjusting the specific time.

主权项

1. A sensorless Brushless Direct Current, BLDC, motor system comprising:
a BLDC motor comprising first to third coils; a comparator comparing a voltage of a specific coil of the first to third coils with a neutral-point voltage to output the compared result; a motor controller generating first and second coil control signals based on the compared result, wherein the voltage of the specific coil becomes equal to the neutral-point voltage and a specific time elapses, and then the motor controller generates the first and second coil control signals; a three-phase inverter supplying a source voltage or ground voltage to the specific coil, or floating the specific coil, in response to the first and second coil control signals; and a mode selector selecting a driving mode of the BLDC motor by adjusting the specific time.