Abstract: A high current interconnection system is provided which can be configured to couple a motor to an inverter. A high current interconnection system comprises a bus bar, a motor winding coupled to the bus bar, and a thermal interface. The motor winding is configured to receive a current. The thermal interface can be coupled to at least one of the motor winding or the bus bar. The thermal interface is configured to reduce a temperature of the motor winding or bus bar which the thermal interface is coupled to.

Abstract: A method and system for operating a power converter having an electrical component and a switch coupled to a voltage source are provided. A signal is received that is representative of a desired current flow through the electrical component. A signal is generated that is representative of a difference between the desired current flow and an actual current flow through the electrical component. A duty cycle for the switch is calculated based on the signal representative of the difference and a voltage generated by the voltage source.

Abstract: A method and system for determining a current flowing through an electrical component are provided. A switch electrically coupled to the electrical component and two voltage sources is activated. The activation of the switch causes current to flow through the electrical component after an amount of time. The amount of time between said activating the switch and the flow of current through the electrical component is determined. The current flowing through the electrical component is measured to determine a measured current value. The measured current value is modified based at least in part on the amount of time between said activating the switch and the flow of current through the electrical component.

Abstract: A method and system for operating a power converter having an electrical component and a switch coupled to a voltage source are provided. A signal is received that is representative of a desired current flow through the electrical component. A signal is generated that is representative of a difference between the desired current flow and an actual current flow through the electrical component. A duty cycle for the switch is calculated based on the signal representative of the difference and a voltage generated by the voltage source.

Abstract: A rotor for an interior permanent magnet machine has a rotor body having an output shaft and a first cavity filled with magnetic material. Second cavities are disposed inboard of the first cavities and are not filled with magnetic material. Non-magnetic rods extend through the second cavities and protrude beyond end faces of the rotor body. The rods are press-fit in blind bores formed in non-magnetic end plates disposed adjacent the end faces of the rotor body. Shrink disks are shrunk around projecting ends of the output shaft in abutting relation with the end plates. In order to prevent induced voltage from generating current in the cage formed by the rods and end plates, an oxide layer is disposed between the rods and blind bores in the end plates.

Abstract: Methods for controlling a multiple DC-to-AC inverter system, which is suitable for an electric or hybrid vehicle application, are disclosed. In one embodiment, if an inverter fails or suffers from degraded performance (faulty inverter), the faulty inverter is disabled and drive signals to a healthy inverter that is coupled to the faulty inverter are updated such that the healthy inverter can remain active without being driven into an over-current condition.

Abstract: A rotor for an interior permanent magnet machine has a rotor body having an output shaft and a first cavity filled with magnetic material. Second cavities are disposed inboard of the first cavities and are not filled with magnetic material. Non-magnetic rods extend through the second cavities and protrude beyond end faces of the rotor body. The rods are press-fit in blind bores formed in non-magnetic end plates disposed adjacent the end faces of the rotor body. Shrink disks are shrunk around projecting ends of the output shaft in abutting relation with the end plates. In order to prevent induced voltage from generating current in the cage formed by the rods and end plates, an oxide layer is disposed between the rods and blind bores in the end plates.

Abstract: A coaxial stack of laminations for a stator of an electrical machine uses laminations that are substantially identical and in direct abutment with one another. Each of the laminations has an outer periphery and an inner periphery with the outer periphery being defined by an array of outwardly projecting pins and the inner periphery being defined by an array of inwardly projecting teeth. The outwardly projecting pins cooperate with a jacket surrounding the stack to provide a cooling space through which cooling liquid flows while the teeth provide spaces therebetween for receiving for receiving stator windings. The number of pins (npin) is proportional to the number of teeth (nth) according to the relationship (2K+1)/(2Kth) times the number of teeth (nth), where K is a selected integer number and Kth is the number of teeth past which each lamination is rotated with respect to adjacent laminations so that spaces between the teeth of adjacent laminations are aligned.

Abstract: An apparatus includes a multi-phase inverter, a fault detector to indicate a detection of a fault, a sensor to provide a speed signal indicative of whether a speed of a PM motor is greater than a transition speed, and a controller. The controller is operable to apply either an open-circuit response or a short-circuit response to the multi-phase inverter. The open-circuit response is applied when the speed of the PM motor is greater than the transition speed and a fault is detected. The short-circuit response is applied when the speed of the PM motor is less than the transition speed and the fault is detected. The transition speed is either a fixed predetermined speed or an adjusted predetermined speed.

Abstract: A multiple DC-to-AC inverter system, which is suitable for an electric or hybrid vehicle application, includes a plurality of inverters controlled by a single controller. One example embodiment includes four three-phase inverters driving one six-phase motor, where the output of the first inverter is coupled to the output of the fourth inverter and the output of the second inverter is coupled to the output of the third inverter. In response to the failure of an inverter, the drive signals to the inverter that is coupled to the faulty inverter are updated such that the partner inverter can remain active without being driven into an over-current condition.

Abstract: A power supply generates alternating current and direct current from a constant-voltage source. A multi-phase pulse width modulation voltage source inverter is connected across the source to output multi-phase alternating current. At least one waveform generator is bridged in parallel with the inverter, with each waveform generator outputting zero-sequence waveform current compensated to maintain the multi-phase current within a predetermined tolerance from a desired set point. A rectifier receives the waveform current and generates direct current.

Abstract: The present invention includes a method for thermal management in a voltage source inverter. The method includes sensing a low output frequency condition, determining a zero vector modulation responsive to the sensed low output frequency condition, and applying the determined zero vector modulation to reduce thermal stress in the voltage source inverter. The step of determining the zero vector modulation responsive to the sensed low output frequency condition includes mapping an output voltage requirement to a space vector structure and determining state switching space vectors based on the mapped output voltage requirement.

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: A drive system that is suitable for high bandwidth current control of a three-phase voltage source inverter in the overmodulation region includes a feedback path that has a harmonic decoupling block that subtracts selected harmonic components from signals representative of a corresponding motor phase current signal. The harmonic decoupling block thereby generates corrected feedback signals. The drive system also includes subtractor blocks that subtract the corrected feedback signals from signals representative of open-loop magnetizing reference currents to generate difference signals. Also included is a modulation block that utilizes the difference signals to produce signals to drive a three-phase voltage source inverter in an overmodulated six-step mode.

Abstract: Methods and apparatus are provided for controlling an inverter with an under-damped L-C filter connected to a load. Samples of the inverter output are processed to generate voltage regulation signals and damping signals. The voltage regulation signals include both regulating and imbalance compensating elements, and are further modified by the damping signals. The modified voltage regulation signals control the switching circuits of the inverter to stabilize the inverter output to the load.

Abstract: Methods and apparatus are provided for controlling a stand-alone four-leg three-phase inverter. The inverter three-phase output is converted from AC domain elements to corresponding DC domain elements. The DC domain elements are processed into combined regulating and imbalance compensating signals, including over-current limiting. The compensating signals are restored to corresponding AC domain signals, and are processed into control inputs for the inverter, in order to stabilize the inverter output when connected to an unbalanced load. The inverter controller can be implemented entirely in software as a control algorithm.

Abstract: A method of fabricating a rotor for an electric traction motor including the steps of forming cavities in the rotor, injecting magnetic material in a portion of the cavities, injecting nonmagnetic material in a portion of the cavities, and post-magnetizing the magnetic material.

Abstract: A method of generating low voltage auxiliary power forms for electric or hybrid vehicle use by tapping power from the traction motor primary winding with a secondary winding and rectifier.

Abstract: An electric motor control system including a stator for producing a magnetic field, a surface mount permanent magnet rotor rotated by the magnetic field, a motor shaft coupled to the rotor, power electronics for controlling the magnetic field in the stator, and where the power electronics controls the q-axis and d-axis current components for the electric motor.

Abstract: A method of fabricating a rotor for an electric traction motor including the steps of forming cavities in the rotor, injecting magnetic material in a portion of the cavities, injecting nonmagnetic material in a portion of the cavities, and post-magnetizing the magnetic material.