Abstract: Apparatus and methods that control motor power in an electric motor such as a stepper motor, advantageously allow improved open-loop motor performance, allow reduced motor hunting, detect stalls, detect out-of-synchronization errors, control and synchronize multiple motors, and can automatically configure motor parameters to provide a motor with a power and load combination that gives an optimized performance. In one embodiment, an EMF commutation circuit detects a rotor position at which to sequence the motor to provide an optimized performance from the motor. In another embodiment, pulse width modulation (PWM) controls power, and the embodiment measures the rotor position within a detent position. Particular embodiments of the invention utilize a motor controller adapted to respond to a commutation signal, a pulse, or both in conjunction with a sensing device, such as an EMF detector or an optical encoder.

Abstract: Apparatus and methods that control motor power in an electric motor such as a stepper motor, advantageously allow improved open-loop motor performance, allow reduced motor hunting, detect stalls, detect out-of-synchronization errors, control and synchronize multiple motors, and can automatically configure motor parameters to provide a motor with a power and load combination that gives an optimized performance. In one embodiment, an EMF commutation circuit detects a rotor position at which to sequence the motor to provide an optimized performance from the motor. In another embodiment, pulse width modulation (PWM) controls power, and the embodiment measures the rotor position within a detent position. Particular embodiments of the invention utilize a motor controller adapted to respond to a commutation signal, a pulse, or both in conjunction with a sensing device, such as an EMF detector or an optical encoder.