Patents by Inventor Mahesh Krishnamurthy
Mahesh Krishnamurthy has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 11929697Abstract: 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: GrantFiled: May 23, 2022Date of Patent: March 12, 2024Assignee: Turntide Technologies Inc.Inventors: Mahesh Krishnamurthy, Trevor Creary
-
Patent number: 11784598Abstract: 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: GrantFiled: February 27, 2022Date of Patent: October 10, 2023Assignee: Turntide Technologies, Inc.Inventors: Trevor A. Creary, Mahesh Krishnamurthy, Piyush C. Desai, Mark Johnston, Timothy Knodel
-
Publication number: 20230208336Abstract: 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: ApplicationFiled: March 2, 2023Publication date: June 29, 2023Inventors: TREVOR CREARY, MAHESH KRISHNAMURTHY, TIM KNODEL
-
Patent number: 11682995Abstract: 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: GrantFiled: March 7, 2022Date of Patent: June 20, 2023Assignee: Turntide Technologies, Inc.Inventors: Mahesh Krishnamurthy, Trevor Creary, Piyush Desai, Mark Johnston
-
Publication number: 20230107792Abstract: A switched reluctance machine comprising at least one rotor comprising a set of rotor poles arranged about a central axis, at least one stator positioned concentric to and radially outward from the central axis and the rotor, the stator having an outer surface and an outer surface active zone; a housing having a sleeve positioned only radially outward from the stator outer surface active zone; at least one housing endplate coupled to an end of said housing; wherein said stator has no direct connection to said housing, and wherein 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.Type: ApplicationFiled: December 11, 2022Publication date: April 6, 2023Inventors: Piyush Desai, Tim Knodel, Bryan Knodel, Earl Fairall, Mark Johnston, Mahesh Krishnamurthy
-
Patent number: 11601081Abstract: 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: GrantFiled: November 1, 2021Date of Patent: March 7, 2023Assignee: Turntide Technologies, Inc.Inventors: Trevor Creary, Mahesh Krishnamurthy, Tim Knodel
-
Publication number: 20220286074Abstract: 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: ApplicationFiled: May 23, 2022Publication date: September 8, 2022Inventors: MAHESH KRISHNAMURTHY, TREVOR CREARY
-
Publication number: 20220190765Abstract: 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: ApplicationFiled: February 27, 2022Publication date: June 16, 2022Inventors: Trevor A. Creary, Mahesh Krishnamurthy, Piyush C. Desai, Mark Johnston, Timothy Knodel
-
Publication number: 20220190766Abstract: 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: ApplicationFiled: March 7, 2022Publication date: June 16, 2022Inventors: MAHESH KRISHNAMURTHY, TREVOR CREARY, PIYUSH DESAI, MARK JOHNSTON
-
Patent number: 11342872Abstract: 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: GrantFiled: April 24, 2021Date of Patent: May 24, 2022Assignee: Turntide Technologies Inc.Inventors: Mahesh Krishnamurthy, Trevor Creary
-
Publication number: 20220085804Abstract: 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: ApplicationFiled: November 28, 2021Publication date: March 17, 2022Inventors: Alejandro Pozo Arribas, Mahesh Krishnamurthy
-
Patent number: 11277061Abstract: 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: GrantFiled: March 18, 2020Date of Patent: March 15, 2022Assignee: Turntide Technologies, Inc.Inventors: Mahesh Krishnamurthy, Mark Johnston, Trevor Creary, Piyush Desai
-
Patent number: 11271509Abstract: 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: GrantFiled: July 5, 2020Date of Patent: March 8, 2022Assignee: Turntide Technologies Inc.Inventors: Mahesh Krishnamurthy, Trevor Creary, Piyush Desai, Mark Johnston
-
Patent number: 11264932Abstract: 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: GrantFiled: July 31, 2020Date of Patent: March 1, 2022Assignee: Turntide Technologies Inc.Inventors: Trevor A. Creary, Mahesh Krishnamurthy, Piyush C. Desai, Mark Johnston, Timothy Knodel
-
Publication number: 20220060132Abstract: 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: ApplicationFiled: November 1, 2021Publication date: February 24, 2022Inventors: TREVOR CREARY, MAHESH KRISHNAMURTHY, TIM KNODEL
-
Patent number: 11190179Abstract: 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: GrantFiled: July 13, 2020Date of Patent: November 30, 2021Assignee: Turntide Technologies Inc.Inventors: Alejandro Pozo Arribas, Mahesh Krishnamurthy
-
Patent number: 11165382Abstract: 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: GrantFiled: March 31, 2018Date of Patent: November 2, 2021Assignee: Turntide Technologies, Inc.Inventors: Trevor Creary, Mahesh Krishnamurthy, Tim Knodel
-
Publication number: 20210242814Abstract: 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: ApplicationFiled: April 24, 2021Publication date: August 5, 2021Inventors: MAHESH KRISHNAMURTHY, TREVOR CREARY
-
Patent number: 11050101Abstract: A method and apparatus for determining and/or monitoring a thermal state of charge or melt fraction of phase change material in a battery system. The battery system includes a plurality of electrochemical cell elements, a supply of a phase change material in thermal contact with the plurality of electrochemical cell elements, and a battery management system that monitors a thermal storage capacity of the phase change material and automatically controls a power of the plurality of electrochemical cell elements as a function of the thermal storage capacity of the phase change material. The battery management system automatically adjusts a power output of the plurality of electrochemical cell elements as a function of the thermal storage capacity of the phase change material to provide a heat output within a predetermined safe temperature limit.Type: GrantFiled: January 9, 2018Date of Patent: June 29, 2021Assignee: ALL CELL TECHNOLOGIES, LLCInventors: Said Al-Hallaj, Mohamad M. Salameh, Siddique Ali Khateeb Razack, Benjamin Schweitzer, Stephen Wilke, Mahesh Krishnamurthy
-
Patent number: 10992247Abstract: 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: GrantFiled: April 6, 2020Date of Patent: April 27, 2021Assignee: Turntide Technologies Inc.Inventors: Mahesh Krishnamurthy, Trevor Creary