One embodiment describes a motor starter, which includes a first single pole switching device that opens to disconnect power from a first winding of a motor; a second single pole switching device that closes after the first switching device opens to connect power to the first winding; a third single pole switching device closes after the second single pole switching device closes to increase power supplied to a second winding of the motor; a fourth single pole switching device that opens after the third single pole switching device closes to disconnect power supplied to a third winding of the motor and to reduce power supplied to the second winding; and a fifth single pole switching device that closes after the fourth switching device opens to connect power to the third winding.

A method of smoothly starting a Hall-less motor includes the steps of applying voltage to two items of a three-phase motor, determining positioning duty and positioning time so that duty cycle progressively increases from zero to prevent jitter during positioning, using fixed duty cycle so that dragging duty cycle equals to positioning duty cycle, setting initial phase-changing time and phase-changing time when dragging is ended, changing phase after timer is interrupted, generating logic signal by three-phase signal generated by three-phase motor, and transmitting to central processor simultaneously using external interruption method. The method adopts low cost hardware circuit structure, optimizes starting algorithm, and simplifies product design. Algorithm optimization is carried out in every step, and it has the advantages of smooth starting process, short starting time, and almost zero starting failure rate.

A method for controlling circuitry of a softstarter arrangement to operate an electric motor for driving a pump is provided, wherein the softstarter circuitry electrically connects the motor to electric mains. The method includes: (i) controlling the circuitry of the softstarter arrangement to accelerate the motor up to full speed in a forward direction; (ii) controlling the circuitry of the softstarter arrangement to decelerate the motor when the motor has run at full speed in the forward direction for a first period of time; (iii) controlling the circuitry of the softstarter arrangement to accelerate the motor up a specified speed in a reverse direction; (iv) controlling the circuitry of the softstarter arrangement to decelerate the motor when the motor has run at the specified speed in the reverse direction for a second period of time; and (v) repeating the steps (i)-(iv) one or more times.

One embodiment describes a three-phase electromechanical switching device, which includes three single-phase switching devices mechanically and electrically coupled in parallel with one another, each single-phase switching device including a direct current electromagnetic operator that in operation receives a direct current control signal for switching of the device, stationary contacts disposed in a respective device housing, and a movable assembly that in operation is displaced by energizing the operator and that include movable contacts that open and close, with the stationary contacts, a single current carrying path through the respective single-phase switching device; in which each of the single-phase switching devices receives control signals from control circuitry coupled to the operators of the respective single-phase switching devices to cause at least one of the single-phase switching devices to open or close the single current carrying path at a desired time coordinated with a current zero-crossing or a predicted current zero-crossing of a phase of three-phase power.

One embodiment describes a three-phase electromechanical switching device, which includes three single-phase switching devices mechanically and electrically coupled in parallel with one another, each single-phase switching device including a direct current electromagnetic operator that in operation receives a direct current control signal for switching of the device, stationary contacts disposed in a respective device housing, and a movable assembly that in operation is displaced by energizing the operator and that include movable contacts that open and close, with the stationary contacts, a single current carrying path through the respective single-phase switching device; in which each of the single-phase switching devices receives control signals from control circuitry coupled to the operators of the respective single-phase switching devices to cause at least one of the single-phase switching devices to open or close the single current carrying path at a desired time coordinated with a current zero-crossing or a predicted current zero-crossing of a phase of three-phase power.

An air conditioner and a startup control method and system for an outdoor fan of the air conditioner. While in a process of charging a bootstrap capacitor in an actuator of a motor of the outdoor fan, an initial rotation state of the motor is detected in real time, and, when charging of the bootstrap capacitor is completed, startup of the motor is correspondingly controlled on the basis of the detected initial rotation state. This allows real time initial startup work state to be acquired when charging of the bootstrap capacitor is completed, thus allowing the motor to be started smoothly, increasing the success rate in starting the motor, and solving the problem of low success rate in starting the motor of an outdoor fan.

Examples include a method for controlling a motor soft-starter for starting an electric motor on a three-phases electric network in order to compensate a misbalance between the windings of the electric motor due to a misbalance between the phases of the electric network.

Disclosed is a clothes treating apparatus and a control method thereof. Specifically, the clothes treating apparatus may include an inverter configured to convert a direct current (DC) input into an alternating current (AC) output and provide the AC output to the motor, and a controller configured to control the inverter in relation to driving of the motor.

Pairs of phases of an AC power source are connected to pairs of phases of a motor in a first sequence that repeats at a first frequency. The motor is braked by connecting pairs of phases of the AC power source to pairs of phases of the motor in a second sequence that is reversed with respect to the first sequence and that repeats at a second frequency less than the first frequency. In further aspects, pairs of phases of an AC power source are connected to pairs of phases of a motor in a first sequence. All of the phases of the motor are subsequently disconnected from the AC power source for a predetermined dwell interval having a duration greater than a time constant of the motor, and thereafter the motor is braked by connecting pairs of phases of the AC power source to pairs of phases of the motor in a second sequence that is reversed with respect to the first sequence. Motor starters implementing such operations are also disclosed.

The present invention relates to an electromagnetic machine comprising: rotation shaft; a stator comprising a multi-phase winding wire; a mover (rotor 1) comprising the multi-phase winding wire and spaced apart from the stator at a preset interval; and a controller for independently controlling a first magnetic field of the stator and a second magnetic field of the mover (rotor 1). The electromagnetic machine according to the present invention can resolve, by means of the mover (rotor 1) and the wound-type stator that can be independently and actively controlled, a torque issue at start-up or when needed and, thereby, has the effects of producing a maximum driving torque while having a minimum size, and of maximizing efficiency.