Brushless motor apparatus

Abstract

A blushless direct current (BLDC) motor apparatus includes: a stator which is provided with a plurality of windings corresponding to N phases and wound in parallel independently of each other; a rotorwhich has a plurality of poles corresponding to the plurality of windings and rotates with respect to the stator by excitation of the windings; a switching unit which is provided in the form of a full H-bridge with respect to each phase, comprises a pair of upper switching devices corresponding to a (+) side of the winding and a pair of lower switching devices corresponding to a (-) side of the winding, and performs a switching operation to supply or not to supply driving power to the winding; a first sensing device which senses the phase of the rotor with respect to the stator to determine whether to turn on or off the upper switching device; a second sensing device which is provided in the latter part than the first sensing device and senses the phase of the rotor with respect to the stator to determine whether to turn on or off the lower switching device; and a controller which uses a partial square wave to drive the upper switching device and the lower switching device on the basis of the sensed phase of the rotor, and controls the lower switching device to be turned off later than the upper switching device by more than a time to exhaust an electric current staying in the winding.

Description

technical field [0001] The present invention relates to a motor device, and more particularly, to a brushless direct current (BLDC) motor device capable of high-speed rotation and high efficiency. Background technique [0002] Compared with motor devices with brushes, brushless direct current (BLDC) motor devices have low noise, long life, simple maintenance (eg, no need to replace brushes), etc. due to the lack of mechanical contact. Therefore, BLDC motor devices are widely used as motors for industrial equipment, home appliances, transportation systems, and the like. [0003] Regarding this motor device, Korean Patent Registration No. 10-0415493 discloses a technology that enables the motor device to rotate at a high speed, have a strong starting torque, and output constant power. [0004] According to this technique, low-efficiency regions (ie, regions where counter electromotive force is generated) are not used, so that the motor device can have advantages of high effic...

AI Technical Summary

Problems solved by technology

However, if the windings of adjacent two slots make the current flow in the same direction, the collision of the magnetic fluxes causes the magnetic fluxes to cancel each other, thereby reducing the efficiency of the motor device

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