Abstract: The system contains a controller unit comprising a memory device, a processing unit, and at least one analog-to-digital converter. A power stage has a plurality of switches, wherein the power stage receives a control signal from the control circuit and a power signal from a power source. The power stage drives two windings of the set of three stator windings to rotate a rotor and maintains one stator winding of the three stator windings undriven. The memory device stores a plurality of values for the driven current and a plurality of demodulated undriven winding voltages. The processing unit compares the plurality of values and periodically calculates a rotor sextant while the rotor rotates. The processing unit compares at least two demodulated undriven winding voltage values corresponding to at least two current values within the rotor sextant to calculate the rotor sextant parity and verify the calculation of the rotor sextant.

Abstract: A system for controlling motor switching in a sensorless BLDC having a stator with three stator windings and a permanent magnet rotor. The system includes a controller unit comprising a control signal generator, a memory device, a processing unit, a signal acquisition device, and an analog-to-digital converter. A power stage controlled by the controller unit has a plurality of switches and drives two windings of the three stator windings with a pulse width modulation signal and leaves one stator of the three stator windings undriven. The processing unit acquires a demodulated measured voltage on the undriven winding. The processing unit calculates a threshold at which the power stage will change which two windings of the three stator windings are driven when the demodulated measured voltage surpasses the threshold.

Abstract: The system discloses structure for synchronizing sequential phase switching in driving a set of stator windings of a multi-phase sensorless brushless permanent magnet DC motor. A drive voltage drives a plurality of the stator windings thereby producing a magnetic field. On an undriven stator winding among the stator windings, a voltage induced by the magnetic field is sampled. The induced voltage changes as a function of a magnetic rotor transitioning across a plurality of angular positions. A first value corresponding to the sampled voltage induced on the currentless winding is compared with a commutation threshold to determine a proper commutation point. The system is switched to a next drive configuration of the sequence when the first value surpasses the threshold.

Abstract: The system contains a controller unit comprising a memory device, a processing unit, and at least one analog-to-digital converter. A power stage has a plurality of switches, wherein the power stage receives a control signal from the control circuit and a power signal from a power source. The power stage drives two windings of the set of three stator windings to rotate a rotor and maintains one stator winding of the three stator windings undriven. The memory device stores a plurality of values for the driven current and a plurality of demodulated undriven winding voltages. The processing unit compares the plurality of values and periodically calculates a rotor sextant while the rotor rotates. The processing unit compares at least two demodulated undriven winding voltage values corresponding to at least two current values within the rotor sextant to calculate the rotor sextant parity and verify the calculation of the rotor sextant.

Abstract: The system discloses structure for synchronizing sequential phase switching in driving a set of stator windings of a multi-phase sensorless brushless permanent magnet DC motor. A drive voltage drives a plurality of the stator windings thereby producing a magnetic field. On an undriven stator winding among the stator windings, a voltage induced by the magnetic field is sampled. The induced voltage changes as a function of a magnetic rotor transitioning across a plurality of angular positions. A first value corresponding to the sampled voltage induced on the currentless winding is compared with a commutation threshold to determine a proper commutation point. The system is switched to a next drive configuration of the sequence when the first value surpasses the threshold.

Abstract: A system for controlling motor switching in a sensorless BLDC having a stator with three stator windings and a permanent magnet rotor. The system includes a controller unit comprising a control signal generator, a memory device, a processing unit, a signal acquisition device, and an analog-to-digital converter. A power stage controlled by the controller unit has a plurality of switches and drives two windings of the three stator windings with a pulse width modulation signal and leaves one stator of the three stator windings undriven. The processing unit acquires a demodulated measured voltage on the undriven winding. The processing unit calculates a threshold at which the power stage will change which two windings of the three stator windings are driven when the demodulated measured voltage surpasses the threshold.