Patent ID: 9178451
Filing Date: 2015-11-03
Classification: H02P

Abstract:
1. A controller for a brushless direct current (BLDC) motor, comprising: a pulse width modulator for providing a plurality of phase control signals to control corresponding ones of a plurality of phases of the BLDC motor; and a control circuit for controlling said pulse width modulator to provide pulses to said plurality of phases to control a speed of the BLDC motor by causing said pulse width modulator to adjust widths of said pulses when a measured current in an active one of a corresponding phase exceeds a threshold in a startup mode, wherein in said startup mode said control circuit controls said pulse width modulator to provide said pulses at a duty cycle to said plurality of phases, and reduces said duty cycle of said pulses based on a time when said measured current in said active one of said plurality of phases exceeds said threshold.