Patents Assigned to Turntide Technologies Inc.
  • Patent number: 11929697
    Abstract: A system and method for reliable control of a high rotor pole switched reluctance machine (HRSRM) utilizing a sensorless reliable control system. The method comprising: energizing at least one of the plurality of stator phases; measuring a first current value and time taken by the first current value to reach a first peak value or preset threshold value of current; determining a self-inductance value; measuring a second current value and time taken by an adjacent un-energized stator phase to reach a second peak value of current; determining a mutual inductance value; and estimating a rotor position utilizing the self-inductance and mutual inductance values; and controlling the HRSRM based on the estimated rotor position.
    Type: Grant
    Filed: May 23, 2022
    Date of Patent: March 12, 2024
    Assignee: Turntide Technologies Inc.
    Inventors: Mahesh Krishnamurthy, Trevor Creary
  • Patent number: 11784599
    Abstract: An SR drive with an acoustic noise reduction system for reducing vibration and acoustic noise in a switched reluctance motor (SRM). The vibration and acoustic noise at specific harmonics of current excitation in SRM are in a proportional relationship with the radial force harmonics acting at SRM stator teeth. The acoustic noise reduction system includes a processor on which is installed an acoustic noise reduction application designed to derive an optimum current waveform for generating an average torque satisfying an optimum torque condition and creating radial force with minimum amplitude at the desired order of harmonics of current excitation. A reduction in the amplitude of the specific radial force harmonics utilizing the optimum current waveform minimizes the vibration and acoustic noise in the SRM. The acoustic noise reduction system applies turn-on and turn-off angles at the optimum current waveform to improve the system efficiency.
    Type: Grant
    Filed: February 6, 2022
    Date of Patent: October 10, 2023
    Assignees: Tokyo Institute of Technology, Turntide Technologies Inc.
    Inventors: Akira Chiba, Candra Adi Wiguna, Jihad Furqani, Piyush Desai
  • Patent number: 11784598
    Abstract: A method and apparatus for quasi-sensorless adaptive control of a high rotor pole switched-reluctance motor (HRSRM). The method comprises the steps of: applying a voltage pulse to an inactive phase winding and measuring current response in each inactive winding. Motor index pulses are used for speed calculation and to establish a time base. Slope of the current is continuously monitored which allows the shaft speed to be updated multiple times and to track any change in speed and fix the dwell angle based on the shaft speed. The apparatus for quasi-sensorless control of a high rotor pole switched-reluctance motor (HRSRM) comprises a switched-reluctance motor having a stator and a rotor, a three-phase inverter controlled by a processor connected to the switched-reluctance motor, a load and a converter.
    Type: Grant
    Filed: February 27, 2022
    Date of Patent: October 10, 2023
    Assignee: Turntide Technologies, Inc.
    Inventors: Trevor A. Creary, Mahesh Krishnamurthy, Piyush C. Desai, Mark Johnston, Timothy Knodel
  • Patent number: 11682995
    Abstract: The present embodiment is a high rotor pole switched reluctance machine (HRSRM) which provides a plurality of combinations of the number of rotor poles Rn and number of stator poles Sn utilizing a numerical relationship defined by a mathematical formula, Rn=2Sn?Fp, when Sn=m×Fp, wherein Fp is the maximum number of independent flux paths in the stator when stator and rotor poles are fully aligned, and m is the number of phases. The mathematical formulation provides an improved noise performance and design flexibility to the machine. The mathematical formulation further provides a specific number of stator and rotor poles for a chosen m and Fp. The HRSRM can be designed with varying number of phases. The HRSRM provides a smoother torque profile due to a high number of strokes per revolution.
    Type: Grant
    Filed: March 7, 2022
    Date of Patent: June 20, 2023
    Assignee: Turntide Technologies, Inc.
    Inventors: Mahesh Krishnamurthy, Trevor Creary, Piyush Desai, Mark Johnston
  • Patent number: 11601081
    Abstract: A method for controlling switched reluctance machine (SRM) utilizing a SRM control system. The method allows for adaptive pulse positioning over a wide range of speeds and loads. An initial rotor position is provided for the SRM utilizing an initialization mechanism. A pinned point on a phase current waveform is defined during an initial current rise phase of the current waveform. A slope of the current rise is determined as the current waveform reaches the pinned point. The slope is then fed to the commutation module of the SRM control system. An error signal from calculated inductance or current slope is used as an input to a control loop in the SRM control system. The time determining module determines an optimum time signal to fire a next pulse. The optimum time signal is fed to the SRM for turning the plurality of SRM switches to on and off states.
    Type: Grant
    Filed: November 1, 2021
    Date of Patent: March 7, 2023
    Assignee: Turntide Technologies, Inc.
    Inventors: Trevor Creary, Mahesh Krishnamurthy, Tim Knodel
  • Patent number: 11342872
    Abstract: A system and method for reliable control of a high rotor pole switched reluctance machine (HRSRM) utilizing a sensorless reliable control system. The method comprising: energizing at least one of the plurality of stator phases; measuring a first current value and time taken by the first current value to reach a first peak value or preset threshold value of current; determining a self-inductance value; measuring a second current value and time taken by an adjacent un-energized stator phase to reach a second peak value of current; determining a mutual inductance value; and estimating a rotor position utilizing the self-inductance and mutual inductance values; and controlling the HRSRM based on the estimated rotor position.
    Type: Grant
    Filed: April 24, 2021
    Date of Patent: May 24, 2022
    Assignee: Turntide Technologies Inc.
    Inventors: Mahesh Krishnamurthy, Trevor Creary
  • Patent number: 11277061
    Abstract: A high rotor pole switched reluctance machine (HRSRM) employs an axial and radial mirroring concept and is represented by a first Multiple Rotor Pole (MRP) formula and second Multiple Stator Pole (MSP) formula. A multiple rotor HRSRM comprises at least two rotors each having a plurality of rotor poles and at least two stators having a plurality of stator poles. The at least two rotors and the at least two stators are positioned about a central axis with the stator placed between the rotors. In other embodiments, the number of stators equals the number of rotors and effectively operate as a single stator and rotor. In yet another embodiment, the effective single stator and rotor type high rotor pole switched reluctance machine is realized as single stator and rotor positioned concentrically around a central axis.
    Type: Grant
    Filed: March 18, 2020
    Date of Patent: March 15, 2022
    Assignee: Turntide Technologies, Inc.
    Inventors: Mahesh Krishnamurthy, Mark Johnston, Trevor Creary, Piyush Desai
  • Patent number: 11271509
    Abstract: The present embodiment is a high rotor pole switched reluctance machine (HRSRM) which provides a plurality of combinations of the number of rotor poles Rn and number of stator poles Sn utilizing a numerical relationship defined by a mathematical formula, Rn=2Sn?Fp, when Sn=m×Fp, wherein Fp is the maximum number of independent flux paths in the stator when stator and rotor poles are fully aligned, and m is the number of phases. The mathematical formulation provides an improved noise performance and design flexibility to the machine. The mathematical formulation further provides a specific number of stator and rotor poles for a chosen m and Fp. The HRSRM can be designed with varying number of phases. The HRSRM provides a smoother torque profile due to a high number of strokes per revolution.
    Type: Grant
    Filed: July 5, 2020
    Date of Patent: March 8, 2022
    Assignee: Turntide Technologies Inc.
    Inventors: Mahesh Krishnamurthy, Trevor Creary, Piyush Desai, Mark Johnston
  • Patent number: 11264932
    Abstract: A method and apparatus for quasi-sensorless adaptive control of a high rotor pole switched-reluctance motor (HRSRM). The method comprises the steps of: applying a voltage pulse to an inactive phase winding and measuring current response in each inactive winding. Motor index pulses are used for speed calculation and to establish a time base. Slope of the current is continuously monitored which allows the shaft speed to be updated multiple times and to track any change in speed and fix the dwell angle based on the shaft speed. The apparatus for quasi-sensorless control of a high rotor pole switched-reluctance motor (HRSRM) comprises a switched-reluctance motor having a stator and a rotor, a three-phase inverter controlled by a processor connected to the switched-reluctance motor, a load and a converter.
    Type: Grant
    Filed: July 31, 2020
    Date of Patent: March 1, 2022
    Assignee: Turntide Technologies Inc.
    Inventors: Trevor A. Creary, Mahesh Krishnamurthy, Piyush C. Desai, Mark Johnston, Timothy Knodel
  • Patent number: 11228260
    Abstract: A method of controlling a switched reluctance motor is disclosed herein. The motor comprises a stator carrying a plurality of phase windings and a rotor. The method comprises activating the phase windings in a sequence selected to apply torque to the rotor, wherein during a cycle of rotation of the rotor the phase windings switch between an active state in which current in the phase winding applies torque to the rotor and an inactive state; applying a voltage to a selected phase winding whilst the selected phase winding is in the inactive state to provide a flux in the selected phase winding; determining the current in the selected phase winding; determining the rotor angle based on the current and the flux; and controlling said activating based on the rotor angle.
    Type: Grant
    Filed: December 11, 2017
    Date of Patent: January 18, 2022
    Assignee: Turntide Technologies, Inc.
    Inventors: Howard Slater, David Hodgson
  • Patent number: 11190179
    Abstract: A gate driver circuit comprises a sensor, an amplifier, a regulator and a gate driver. The sensor is configured to sense a collector-emitter voltage and includes a first resistor and a second resistor connected in series, a high voltage diode connected between the series connected first and second resistors and a first capacitor connected parallel to the second resistor. The amplifier is configured to amplify a sensor output voltage and includes a non-inverting operational amplifier controlled by means of a plurality of resistors, a voltage follower connected to an output terminal of the non-inverting operational amplifier through a first diode and a third resistor connected across the first diode and the voltage follower. The regulator is configured to regulate a regulator output voltage based on an amplifier voltage. The gate driver is configured to connect/disconnect the regulator output voltage to the base terminal of the BJT.
    Type: Grant
    Filed: July 13, 2020
    Date of Patent: November 30, 2021
    Assignee: Turntide Technologies Inc.
    Inventors: Alejandro Pozo Arribas, Mahesh Krishnamurthy
  • Patent number: 11165382
    Abstract: A method for controlling switched reluctance machine (SRM) utilizing a SRM control system. The method allows for adaptive pulse positioning over a wide range of speeds and loads. An initial rotor position is provided for the SRM utilizing an initialization mechanism. A pinned point on a phase current waveform is defined during an initial current rise phase of the current waveform. A slope of the current rise is determined as the current waveform reaches the pinned point. The slope is then fed to the commutation module of the SRM control system. An error signal from calculated inductance or current slope is used as an input to a control loop in the SRM control system. The time determining module determines an optimum time signal to fire a next pulse. The optimum time signal is fed to the SRM for turning the plurality of SRM switches to on and off states.
    Type: Grant
    Filed: March 31, 2018
    Date of Patent: November 2, 2021
    Assignee: Turntide Technologies, Inc.
    Inventors: Trevor Creary, Mahesh Krishnamurthy, Tim Knodel
  • Patent number: 10992247
    Abstract: A system and method for reliable control of a high rotor pole switched reluctance machine (HRSRM) utilizing a sensorless reliable control system. The method comprising: energizing at least one of the plurality of stator phases; measuring a first current value and time taken by the first current value to reach a first peak value or preset threshold value of current; determining a self-inductance value; measuring a second current value and time taken by an adjacent un-energized stator phase to reach a second peak value of current; determining a mutual inductance value; and estimating a rotor position utilizing the self-inductance and mutual inductance values; and controlling the HRSRM based on the estimated rotor position.
    Type: Grant
    Filed: April 6, 2020
    Date of Patent: April 27, 2021
    Assignee: Turntide Technologies Inc.
    Inventors: Mahesh Krishnamurthy, Trevor Creary
  • Patent number: RE49723
    Abstract: A power electronics assembly for an electric motor controller. The power electronics assembly comprises an insulated metal substrate, a composite material substrate, and a bolt having a bolt head and a bolt shaft for mechanically coupling the composite material substrate to the insulated metal substrate. The power electronics assembly also includes an electrically conductive sleeve configured to be held between a first electrical contact carried by the insulated metal substrate and a second electrical contact carried by the composite material substrate and the bolt is configured to clamp the composite material substrate to the insulated metal substrate to force the electrically conductive sleeve against the first electrical contact and the second electrical contact.
    Type: Grant
    Filed: September 21, 2021
    Date of Patent: November 7, 2023
    Assignee: Turntide Technologies, Inc.
    Inventors: Peter Barrass, Matt Jackson