Abstract: A sensorless position estimation and control system and method for a permanent magnet electric motor of a powertrain system of a vehicle involve determining a reference torque to be achieved by the electric motor based on a set of vehicle operating parameters, determining a reference current magnitude to achieve the determined reference torque using a lookup table, determining current commands for the electric motor based on the determined reference current magnitude and a fixed reference current angle, injecting a high frequency voltage into a voltage control loop for the electric motor and estimating, by the controller, a position of a rotor of the electric motor thereafter, and controlling a current provided to the electric motor based on the determined current commands and the estimated rotor position.

Abstract: The present invention relates to a pharmaceutical composition of ferric citrate or a pharmaceutically acceptable salt and one or more pharmaceutically acceptable excipients. The present invention specifically relates to oral pharmaceutical composition of ferric citrate and one or more pharmaceutically acceptable excipients. Further, the present invention relates to stable pharmaceutical composition of ferric citrate or a pharmaceutically acceptable salt which improves patient compliance by enhancing ease of administration of the above mentioned pharmaceutical composition. Moreover, the present invention describes the methods employed for manufacturing the above mentioned oral pharmaceutical composition of ferric citrate.

Abstract: A sensorless position estimation and control system and method for a permanent magnet electric motor of a powertrain system of a vehicle involve determining a reference torque to be achieved by the electric motor based on a set of vehicle operating parameters, determining a reference current magnitude to achieve the determined reference torque using a lookup table, determining current commands for the electric motor based on the determined reference current magnitude and a fixed reference current angle, injecting a high frequency voltage into a voltage control loop for the electric motor and estimating, by the controller, a position of a rotor of the electric motor thereafter, and controlling a current provided to the electric motor based on the determined current commands and the estimated rotor position.

Abstract: Methods and apparatus are provided for an electric vehicle embodying an axial flux traction motor directly coupled to a wheel thereof. The traction motor comprises a stator having coils for producing a magnetic field, an annular rotor magnetically coupled to the stator and mechanically to an output shaft. Permanent magnets of alternating polarity are mounted on the annular rotor. Magnetic shunts bridge a portion of the stator slots above the coils. The magnets are arranged in groups with group-to-group spacing exceeding magnet-to-magnet spacing. Adjacent edges of the magnets diverge. The method comprises, looking up d- and q-axis currents to provide the requested torque and motor speed for the available DC voltage, combining at least one of the d- and q-axis currents with a field weakening correction term, converting the result from synchronous to stationary frame and operating an inverter therewith to provide current to the coils of the motor.

Abstract: Methods and apparatus are provided for generating zero-sequence voltages based on voltage commands and a motor output signal. At least one of the methods includes, but is not limited to, receiving a torque command and generating three-phase voltage commands based on the torque command. The method also includes, but is not limited to, generating a motor output responsive to the three-phase voltage commands and generating three-phase zero-sequence voltage samples based on the three-phase voltage commands and the motor output.

Abstract: A method of controlling an IPM machine having a salient rotor. Stator terminal signals are measured and rotated to obtain synchronous reference frame current signals. A rotor position is estimated based on an impedance generated using the rotor and included in the current signals. The estimated rotor position is used to control the machine. An alternator-starter system in which this method is used can provide high cranking torque and generation power over a wide speed range while providing operational efficiency.

Abstract: A method of starting a permanent magnet machine. A machine stator voltage in a stationary reference frame is sensed. An initial speed of a rotor of the machine is estimated based on the sensed voltage, and state variables of control algorithms are initialized based on the estimated initial speed. This method can provide smooth startup and/or restart at any speed.

Abstract: A control system for an electric machine includes a flux weakening module, which includes a voltage magnitude calculator that receives d-axis and q-axis command voltages and that generates a voltage magnitude. An error circuit compares the voltage magnitude to a reference voltage and generates an error signal. A controller receives the error signal and generates a feedback flux correction signal. A limiter limits the feedback flux correction signal to a predetermined flux value and generates a limited feedback flux correction signal. A feedforward stator flux generating circuit generates a feedforward stator flux signal. A summing circuit sums the feedforward stator flux signal and the limited feedback flux correction signal to generate a final stator flux command.

Abstract: A control system and method for an electric machine includes a first calculation module that receives a modified torque command and a calculated stator flux command and that generates first and second current commands and first and second voltage commands. A voltage magnitude calculation module generates a voltage magnitude based the first and second voltage commands. A reference voltage calculator module generates a reference voltage based on a DC link voltage, an angular stator velocity and the first and second current commands. A flux weakening module generates the calculated flux command based on the angular stator velocity, the reference voltage and the voltage magnitude.

Abstract: A method for decoupling a harmonic signal from an input signal wherein the harmonic signal is harmonic relative to a signal other than the input signal. An angular position of the other signal is multiplied by a value representing the harmonic to obtain an angular position multiple. A harmonic decoupling block uses the angular position multiple to obtain correction signals representing the harmonic signal, and subtracts the correction signals from the input current to decouple the harmonic signal from the input signal. This method is useful for decoupling unwanted harmonics from currents into which high-frequency signals have been injected for control of electric motors.

Abstract: The present invention includes a method for managing processor execution time in a motor controller. The method includes receiving motor speed data, comparing the received motor speed data to predetermined motor speed ranges, determining a motor speed range based on the comparison, and modulating an inverter switching frequency of the motor controller processor based on the motor speed range. The step of receiving motor speed data may include receiving machine terminal information, processing the received machine terminal information utilizing a sensorless control algorithm, and determining motor speed data based on the processed information. The step of modulating the inverter switching frequency may include determining a modified inverter switching frequency value based on the determined motor speed range and providing the modified inverter switching frequency value to a processor control algorithm.

Abstract: Methods and apparatus are provided for an electric vehicle embodying an axial flux traction motor directly coupled to a wheel thereof. The traction motor comprises a stator having coils for producing a magnetic field, an annular rotor magnetically coupled to the stator and mechanically to an output shaft. Permanent magnets of alternating polarity are mounted on the annular rotor. Magnetic shunts bridge a portion of the stator slots above the coils. The magnets are arranged in groups with group-to-group spacing exceeding magnet-to-magnet spacing. Adjacent edges of the magnets diverge. The method comprises, looking up d- and q-axis currents to provide the requested torque and motor speed for the available DC voltage, combining at least one of the d- and q-axis currents with a field weakening correction term, converting the result from synchronous to stationary frame and operating an inverter therewith to provide current to the coils of the motor.