15results about "Synchronous motors starters" patented technology

The present invention refers to a starting method with two-levels modified and discrete fixed-time or fixed-frequency hysteresis current controller, under high load conditions, of a BLDC motor (10) with trapezoidal-shaped induced voltages, wherein the BLDC motor (10) is driven by an inverter bridge (30) with only one current sensor (20) positioned in the busbar, controlled by means of a processing unit associated to an analog-digital converter, wherein the novelty basically comprises the fact that: the intensity of the BLDC motor current (Im) is controlled by means of the two-levels and discrete fixed-time or fixed-frequency hysteresis current controller.

Described is a method of aligning a stationary rotor of a polyphase synchronous motor having a permanent magnet rotor to a configured rotor angle (θ). The method includes determining corresponding polyphase drive voltages for the synchronous motor based on a user-specified value of a two-axis synchronously rotating reference frame vector voltage (V) for a selected one of two axis of the two-axis synchronously rotating reference frame. Then, determining corresponding polyphase drive voltages for the synchronous motor; and applying said polyphase drive voltages for a predetermined, selected, or calculated time period to rotate the stationary rotor to align said rotor with said configured rotor angle (θ).

A motor starting method and a motor starting circuit are disclosed. The motor starting method includes: (1) obtaining the rotor current position; (2) asynchronously driving the motor at the current rotor position and the rotation direction to gradually increase the open-loop angle to a target angle and gradually increase the quadrature-axis reference current, wherein the open-loop angular increment gradually increases with time to implement smooth starting; and (3) motor entering a closed-loop control mode. By introducing the open-loop angle, open-loop angular increment, and angular addition increment, implementing the hardware starting circuit becomes easier, only one adder can complete starting, consuming only a few hardware, thereby releasing the CPU resources. This smooth starting approach reduces the “gear shifting” feeling, speeds up the starting process, and lowers the risk of inversion. The technique can be applied to other motors with shared computational logic to reduce costs.

The present technology relates to soft-starts of alternating current (AC) motors, and particularly, to controlling a soft-start of an AC motor using a configuration of transistors and diodes. A system may include processing circuitry and gating circuitry. The gating circuitry may include a first transistor coupled to an AC voltage supply, a second transistor coupled to the first transistor and to an AC motor, a first diode coupled across current path terminals of the first transistor, and a second diode coupled across current path terminals of the second transistor. The processing circuitry may be configured to monitor voltage and current of the AC voltage supply and provide gating signals to the control terminals of the first and second transistors to control operations of the first and second transistors based at least in part on one or more desired firing angles and the voltage or current of the AC voltage supply.

The application belongs to the technical field of beam pumping unit, in particular to a power unit of beam pumping unit, which comprises a main reducer, an auxiliary reducer, a permanent magnet synchronous motor and a motor frequency converter controller, the auxiliary reducer comprises an auxiliary reducer driven large gear and an auxiliary reducer driving small gear which are engaged with each other, the auxiliary reducer driven large gear is installed on the input shaft of the main reducer, and the auxiliary reducer driving small gear is installed on the motor shaft of the permanent magnet synchronous motor; the auxiliary reducer driven large gear comprises a hub, a gear ring and a plurality of shock absorbing springs, the gear ring is sleeved on the hub and is in clearance fit, a plurality of rectangular slots are uniformly distributed in the circumferential direction at the contact position of the hub and the gear, and the shock absorbing springs are installed in the rectangular slots in a compressed state; the auxiliary reducer driven large gear and the auxiliary reducer driving small gear are both herringbone gears. The application has high transmission efficiency, high reliability, continuous adjustable pumping unit stroke, and can meet the needs of matching with full series of beam pumping units.

The present technology relates to soft-starts of alternating current (AC) motors, and particularly, to controlling a soft-start of an AC motor using a configuration of transistors and diodes. A system may include processing circuitry and gating circuitry. The gating circuitry may include a first transistor coupled to an AC voltage supply, a second transistor coupled to the first transistor and to an AC motor, a first diode coupled across current path terminals of the first transistor, and a second diode coupled across current path terminals of the second transistor. The processing circuitry may be configured to monitor voltage and current of the AC voltage supply and provide gating signals to the control terminals of the first and second transistors to control operations of the first and second transistors based at least in part on one or more desired firing angles and the voltage or current of the AC voltage supply.

A method and apparatus for open loop starting of a three phase motor that reduces acoustic noise. During rotor alignment of the motor, a maximum level of phase current to the motor exists. After rotor alignment, open loop motor starting is performed during which the phase current has a first slope. At a selected time, such as when the frequency of the phase current reaches a first threshold, the phase current transitions to a second slope.

A method for automatically setting an angular position sensor of a magnet rotor in relation to a stator of a synchronous machine, including an angle error compensator which adjusts the angles measured by the angular position sensor by an angular difference calculated by imposing a direct setpoint current equal to zero and by comparing a setpoint voltage with a quadrature return current, a direct return current resulting from a direct Park transform of current measured at the stator phase outputs and a rotor electrical speed, a predetermined value corresponding to the rotor magnet flux, and a quadrature inductance.

To reduce the number of parts in the motor drive system. [Solution] The ship's propulsion system comprises an electric motor and a motor drive device that drives the electric motor. The motor drive device has a power input terminal and a ground terminal connected to a ground line, and comprises a drive circuit that supplies power to the electric motor, an electrical resistance element, and a connection device. The connection device performs a first connection pattern in which the power input terminal is electrically connected to the power line via the electrical resistance element, and a second connection pattern in which the power input terminal is electrically connected to the ground line via the electrical resistance element.

In some implementations, a synchronous electric machine may include multiple virtual poles and a control device. The control device may control magnetic polarities of the multiple virtual poles to create a set of effective poles. Each effect pole, included in the set of effective poles, includes one or more virtual poles of the multiple virtual poles. The control device may apply one or more input signals to the one or more virtual poles to generate a rotating magnetic field at an applied frequency.

A boat propulsion device includes an electric motor and a motor drive device that drives the electric motor. The motor drive device includes a power input terminal, a ground terminal connected to a ground line, a drive circuit supplying electric power to the electric motor, an electrical resistive element, and a connection device. The connection device executes a first connection pattern in which the power input terminal is electrically connected to the power line via the electrical resistive element, and a second connection pattern in which the power input terminal is electrically connected to the ground line via the electrical resistive element.

The invention relates to a method for starting a rotational speed-controlled electric motor of a centrifugal pump. The centrifugal pump has at least one impeller which is driven by the electric motor and which rotates at a positive rotational speed during a regular pump operation in order to pump a pumped medium from a suction side to a pressure side of the centrifugal pump in an intended manner, and the rotational speed of the motor is controlled in a transmitter-free manner without means for determining the position of the rotor. The invention is characterized in that prior to starting the centrifugal pump, a current measurement is used in order to detect whether the impeller is being rotated by an external flow and if so, in which direction. If a positive rotational speed produced by the external flow is detected, the motor is actuated according to a rotational speed ramp beginning with a rotational speed target value of null, and if a negative rotational speed produced by the external flow is detected, the motor is actuated according to a rotational speed ramp beginning with a negative rotational speed target value.

Method for starting an EC motor comprising a stator and a rotor, comprising the steps: a) determining a first position of the rotor at rest by means of discrete signal injection (101); b) accelerating the rotor by means of a controlled rotating field (103); c) determining a rotational speed of the rotor based on a back EMF after reaching a predetermined rotating field frequency in step b) (105); d) comparing the rotational speed determined in step c) with a first predetermined rotational speed value (107); and e) if the rotational speed determined in step c) is greater than the first predetermined rotational speed value: determining a second position of the rotor based on the back EMF and switching to closed-loop operation based on the back EMF (109).