Abstract: A proportional integrator for control of a motor drive arranged to be connected in parallel with one or more other motor drives to drive a common load. The proportional integrator includes means to receive an input command signal and to compare with a local measured signal from the motor drive and to output a local control signal for that motor drive, further comprising a global input signal indicative of the behaviour of the one or more other motor drives, the global input signal being incorporated into the proportional integral function with the input command signal and the local measured signal to provide the local control signal.

Abstract: A proportional integrator for control of a motor drive arranged to be connected in parallel with one or more other motor drives to drive a common load. The proportional integrator includes means to receive an input command signal and to compare with a local measured signal from the motor drive and to output a local control signal for that motor drive. Also includes are a global input signal indicative of the behaviour of the one or more other motor drives, the global input signal being incorporated into the proportional integral function with the input command signal and the local measured signal to provide the local control signal.

Abstract: An electric motor system that comprises a motor that comprises a rotor having a magnet mounted thereto and a stator that comprises one or more motor phase windings for driving rotation of the rotor when the motor phase windings receive an input voltage from an electrical power supply. The system has a controller that executes a back “EMF” observer that is operable to estimate a rotor angle by observing a back electromotive force induced in the stator by the rotor. Filtering is applied to the back EMF signal to reduce harmonics prior to determining the rotor angle.

Abstract: There is provided herein a method of advancing phase of a DQ reference frame in a Field Oriented Control, FOC, algorithm for a permanent magnet motor. The method comprises: monitoring a component of the stator voltage demand of the permanent magnet motor, when the component of the stator voltage demand surpasses a threshold, calculating a phase advance angle, ?adv, based on a gain multiplied by the difference between the component of stator voltage demand and the threshold; and advancing phase of the DQ reference frame in the FOC algorithm based on the calculated phase advance angle, up to a maximum phase advance angle when motor speed is positive, or down to a minimum phase angle when motor speed is negative.

Abstract: There is provided herein an electrical motor and associated motor drive. The motor comprises an output shaft, and a speed sensor configured to measure the speed of the output shaft. The motor drive comprises a controller configured to output a current demand for the motor based on a speed error between a desired speed of the output shaft and the measured speed of the output shaft, and a feedback signal of the output current demand scaled by a first gain.

Abstract: Methods of operating electric motor systems that comprise electric motors comprising a rotor having a magnet mounted thereto. The electric motor is initially operated in an open loop mode in which the rotor angle is estimated based on the input voltage frequency. Once the motor is running at sufficient speed, a transition to closed loop mode operation is performed, wherein the rotor angle is determined using an observed back EMF. To provide a smoother open loop to closed loop transition, the rotor angle is determined during a transition period as a function of both the open loop rotor angle and the closed loop rotor angle.

Abstract: Methods, systems, and storage media for searching for products through a social media platform are disclosed. Exemplary implementations may: receive a selection of an item in a post on the social media platform; generate a digital fingerprint of the item in the post; compare the digital fingerprint with a catalog of digital fingerprints; determine a similarity score between the digital fingerprint and individual digital fingerprints of the catalog of digital fingerprints; determine a subset of digital fingerprints that have similarity scores above a threshold, the subset of digital fingerprints corresponding to a subset of items for sale; and cause display of the subset of items for sale through a user interface of the social media platform.

Abstract: A system for providing power to one or more loads includes a plurality of power converters where each power converter is configured to be arranged in a parallel configuration with one or more additional power converters so as to provide power to the one or more loads. The system also includes a central controller configured to receive a plurality of local voltage reference values from each of the power converters, output a global voltage reference value based on the local voltage reference values, and transmit the global voltage reference value to each of the power converters.

Abstract: A system for controlling one or more loads. The system comprises a plurality of power converters, wherein each power converter is configured to be arranged in a parallel configuration with one or more additional power converters so as to control the one or more loads, and a central controller configured to output a common reference based on local current or voltage values received from each power converter; and transmit the common reference to each of the power converters. Each power converter comprises an inverter configured to control the one or more loads based on voltage switching signals, a module configured to provide the voltage switching signals to the inverter according to a modulation scheme.

Abstract: A power converter for providing power to one or more loads, wherein the power converter is configured to be arranged in a parallel configuration with one or more additional power converters. The power converter comprises an inverter for receiving an input voltage and converting this to an output voltage having an associated output current, a module configured to modulate the output voltage using a modulation scheme and first and second feedback circuits.

Abstract: A motor drive comprises a rectifier circuit portion arranged to receive an externally supplied AC voltage and to generate a DC bus voltage. An inverter circuit portion is arranged to receive the DC bus voltage (VDC_Bus) and to generate an AC output voltage (Vout) for supply to an external load. A DC bus portion is connected between the rectifier and the inverter. An inductor (L1) is connected in series along a bus conductor between the rectifier and inverter, and a DC link capacitor (C1) is connected in parallel between the bus conductors. A voltage across the DC link capacitor (C1) is input to a tuneable notch filter arranged to supply a filtered signal. A controller varies the resonant frequency of the notch filter to a plurality of values across an operational range and modulates a supply current provided by the inverter with a probe current signal at the resonant frequency.

Abstract: A proportional integrator for control of a motor drive arranged to be connected in parallel with one or more other motor drives to drive a common load. The proportional integrator includes means to receive an input command signal and to compare with a local measured signal from the motor drive and to output a local control signal for that motor drive. Also includes are a global input signal indicative of the behaviour of the one or more other motor drives, the global input signal being incorporated into the proportional integral function with the input command signal and the local measured signal to provide the local control signal.

Abstract: There is provided a system for providing (e.g., configured to provide) power to one or more loads. The system comprises a plurality of power converters, wherein each power converter is configured to be arranged in a parallel configuration with one or more additional power converters so as to provide power to the one or more loads. The system further comprises a central controller configured to receive a plurality of local current measurement values from each of the power converters, output a global current measurement value based on the local current measurement values, and transmit the global current measurement value to each of the power converters, wherein each power converter comprises an inverter for receiving an input voltage and converting this to an output voltage having one or more associated output current(s).

Abstract: A system for providing power to one or more loads includes a plurality of power converters where each power converter is configured to be arranged in a parallel configuration with one or more additional power converters so as to provide power to the one or more loads. The system also includes a central controller configured to receive a plurality of local voltage reference values from each of the power converters, output a global voltage reference value based on the local voltage reference values, and transmit the global voltage reference value to each of the power converters.

Abstract: A power converter for providing power to one or more loads, wherein the power converter is configured to be arranged in a parallel configuration with one or more additional power converters. The power converter comprises an inverter for receiving an input voltage and converting this to an output voltage having an associated output current, a module configured to modulate the output voltage using a modulation scheme and first and second feedback circuits.

Abstract: A motor drive comprises a rectifier circuit portion arranged to receive an externally supplied AC voltage and to generate a DC bus voltage. An inverter circuit portion is arranged to receive the DC bus voltage (VDC_Bus) and to generate an AC output voltage (Vout) for supply to an external load. A DC bus portion is connected between the rectifier and the inverter. An inductor (L1) is connected in series along a bus conductor between the rectifier and inverter, and a DC link capacitor (C1) is connected in parallel between the bus conductors. A voltage across the DC link capacitor (C1) is input to a tuneable notch filter arranged to supply a filtered signal. A controller varies the resonant frequency of the notch filter to a plurality of values across an operational range and modulates a supply current provided by the inverter with a probe current signal at the resonant frequency.

Abstract: A filter for motor speed measurement signals includes one or more resonators configured to filter signals having a frequency that is proportional by a predetermined factor to the frequency of the motor whose speed is measured.