Abstract: A motor controller configured to drive a permanent magnet synchronous motor (PMSM) with Field Oriented Control (FOC), includes a current controller configured to generate control signals for driving the PMSM. The current controller is configured to measure current information of the PMSM, including a direct-axis motor current and a quadrature-axis motor current. The current controller includes a direct-axis current regulator configured to receive a direct-axis reference current and the direct-axis motor current to generate a direct-axis error value based on a difference between the direct-axis reference current and the direct-axis motor current. The current controller includes a voltage regulator configured to regulate a DQ voltage vector comprising a direct-axis motor voltage and a quadrature-axis motor voltage, wherein the voltage regulator generates the direct-axis motor voltage based on the direct-axis error value and a voltage vector limiting function to drive the direct-axis motor current to zero.

Abstract: A motor controller configured to drive a permanent magnet synchronous motor (PMSM) with Field Oriented Control (FOC), includes a current controller configured to generate control signals for driving the PMSM. The current controller is configured to measure current information of the PMSM, including a direct-axis motor current and a quadrature-axis motor current. The current controller includes a direct-axis current regulator configured to receive a direct-axis reference current and the direct-axis motor current to generate a direct-axis error value based on a difference between the direct-axis reference current and the direct-axis motor current. The current controller includes a voltage regulator configured to regulate a DQ voltage vector comprising a direct-axis motor voltage and a quadrature-axis motor voltage, wherein the voltage regulator generates the direct-axis motor voltage based on the direct-axis error value and a voltage vector limiting function to drive the direct-axis motor current to zero.

Abstract: This application discusses techniques for providing sensorless rotor position information of a multiple phase motor without using predetermined motor parameters or models, other than the number of phases of the motor. In certain examples, motor rotor position information can be provided using samples of current from zero-voltage vectors of the motor windings.

Abstract: The present disclosure provides a system and method to determine at least one parameter of a motor, such as an inductance. The inductance can be determined, such as based on one or more digitally sampled motor winding currents. A digital filter can be applied to the digital samples such as to determine a slope of the motor winding currents. The digital filter can include a least squares fit that can be applied to the digital samples, such as to determine a slope of the motor winding currents. The least squares fit can be determined based on a computation of central tendencies such as an average value of time, an average value of current, an average value of the square of time, and the average value of the product of time and current. The average values can be determined recursively to provide improved computational speed.

Abstract: This application discusses techniques for providing sensorless rotor position information of a multiple phase motor without using predetermined motor parameters or models, other than the number of phases of the motor. In certain examples, motor rotor position information can be provided using samples of current from zero-voltage vectors of the motor windings.

Abstract: The present disclosure provides a system and method to determine at least one parameter of a motor, such as an inductance. The inductance can be determined, such as based on one or more digitally sampled motor winding currents. A digital filter can be applied to the digital samples such as to determine a slope of the motor winding currents. The digital filter can include a least squares fit that can be applied to the digital samples, such as to determine a slope of the motor winding currents. The least squares fit can be determined based on a computation of central tendencies such as an average value of time, an average value of current, an average value of the square of time, and the average value of the product of time and current. The average values can be determined recursively to provide improved computational speed.

Abstract: According to one embodiment, a system for actively balancing power between several power units is disclosed. Each of the power units includes a corresponding group of cascoded energy cells. The system for actively balancing power comprises a group of buck/boost circuits used in each of the power units for maintaining an internal power balance among the corresponding group of cascoded energy cells, and an energy distribution circuit for responding to a respective energy need in each of the power units. The energy distribution circuit is configured to transfer energy between the power units to balance power among the power units according to their respective energy needs. In one embodiment, a method for actively balancing power between several power units comprises maintaining the internal power balance among the group of cascoded energy cells within each of the power units, and transferring energy between the power units as needed.

Abstract: According to one embodiment, a system for actively balancing power between several power units is disclosed. Each of the power units includes a corresponding group of cascoded energy cells. The system for actively balancing power comprises a group of buck/boost circuits used in each of the power units for maintaining an internal power balance among the corresponding group of cascoded energy cells, and an energy distribution circuit for responding to a respective energy need in each of the power units. The energy distribution circuit is configured to transfer energy between the power units to balance power among the power units according to their respective energy needs. In one embodiment, a method for actively balancing power between several power units comprises maintaining the internal power balance among the group of cascoded energy cells within each of the power units, and transferring energy between the power units as needed.

Abstract: Resolver systems are described that generate an estimate &phgr; of a rotatable member's position angle &thgr; and provide fault signals which monitor the reliability and accuracy of the estimate. The fault signals are formed from a monitor signal which multiplies resolver and estimate signals to derive information on the absolute and relative levels of resolver sense signals. At least one fault signal is formed from a loop error signal of the system servo loop. The fault signals report on, for example, mismatched sense signals, out-of-range sense signals and loss of position tracking to thereby enhance accuracy and safety in various resolver applications.

Abstract: A direct current brushless electric motor has a rotor, and a stator with inwardly extending teeth, between each pair of which a winding slot is defined. The radially inward face of each tooth has a dummy slot shaped so the reluctance forces between rotor and stator due to the presence of the dummy slots are the same as those due to the winding slots. Motor control arrangement incorporates a current feedback loop based on the incoming phase of each phase combination in the phase energization sequence in a driving mode and phase changeover may be initiated by Hall devices, two for each transition point, underlying the axial ends of the rotor magnets. The control arrangement may incorporate a pulse width modulation power supply permitting the establishment of bias currents under motor standstill conditions.

Abstract: In a screened inductance sensor having a drive winding, a sense winding, and a conductive screen for varying the induced voltage in the sense winding by reason of the eddy currents generated in the conductive screen in the presence of the drive field, a physical barrier is interposed between the region of the sensor in the windings are located and the region in which the screen is located. These regions are fully environmentally isolated from each other by the physical barrier. The construction is especially suited to screened inductance level gauges, in particular for fuel tanks, where the conductive screen is part of a float assembly in contact with the fuel, but the electrical windings are kept dry in a separate portion of the gauge.

Abstract: In a sensor having a drive winding for establishing a forward field, an electrically conductive screen is displaceable relative to a sense winding. In the presence of the drive field, eddy currents are generated in the screen to establish a counter-field opposing the forward field, so that the sense winding is shaded by the screen to a varying extent during relative displacement of screen and sense winding and the voltage induced in the sense winding is accordingly correspondingly varied. Application of a high frequency input to the drive winding results in a modulated output from the sense winding which may be demodulated to provide a signal indicative of screen position relative to sense winding. The position signal may be further processed to provide a speed signal. The sensor may assume a multiplicity of linear or planar, rotational and axial or solenoidal configurations.

Abstract: A direct current brushless electric motor has a rotor, and a stator with inwardly extending teeth, between each pair of which a winding slot is defined. The radially inward face of each tooth has a dummy slot shaped so the reluctance forces between rotor and stator due to the presence of the dummy slots are the same as those due to the winding slots. Motor control means incorporate a current feedback loop based on the incoming phase of each phase combination in the phase energization sequence in a driving mode and phase changeover may be initiated by Hall devices, two for each transition point, underlying the axial ends of the rotor magnets. The control means may incorporate a pulse width modulation power supply permitting the establishment of bias currents under motor standstill conditions.

Abstract: In a sensor having a drive winding for establishing a forward field, an electrically conductive screen is displaceable relative to a sense winding. In the presence of the drive field, eddy currents are generated in the screen to establish a counter-field opposing the forward field, so that the sense winding is shaded by the screen to a varying extent during relative displacement of screen and sense winding and the voltage induced in the sense winding is accordingly correspondingly varied. Application of a high frequency input to the drive winding results in a modulated output from the sense winding which may be demodulated to provide a signal indicative of screen position relative to sense winding. The position signal may be further processed to provide a speed signal. The sensor may assume a multiplicity of linear or planar, rotational and axial or solenoidal configurations.