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 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 a method of using the same for an electric machine having a random number generating module generating a random number ranging from a first value to a second value, a multiplying module multiplying the random number and a sample rate to generate an random delay value; and a delay limiter module limiting the random delay value as a function of speed of the electric machine and generating a limited delay value.

Abstract: An electric cord utilizing flat strip metal under tension to simplify rewinding the cord. The apparatus comprises a spring biased metal clad within a non-conducting sheath. The spring-loaded metal is biased to effect a concave surface in the general axis congruent to the extreme or long axis. The preloaded spring metal coils in its natural state. The embodiment of the invention locates multiple strips of spring metal in a parallel configuration. The apparatus confines the linear metal strips within a plastic or alternate non-conductor sheath configured to bend or distort the apparatus parallel to the long axis. The apparatus can then be distorted along the major axis to counteract the spring tension delaying the natural coiling of the electric cord. In a basic embodiment the distortion is applied by folding the electric cord along the major axis producing a ridged configuration and resisting the spring from coiling.

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.