Karma Automotive LLC

Geng Niu

Lixin Tang

Younes Sangsefidi

Saleh Ziaieinejad

Parisa Mohammadalizadeh Shabestari

Khanh Nguyen

Xiaohang Yu

Kevin Y Zhang

Lance Liang Zhou

Harshith Kulai

An online method of detecting and compensating for errors in flux estimation in operation of a motor system. The method includes determining a voltage compensation term by comparing an expected voltage and an actual voltage. The method also includes determining a flux compensation term by passing the voltage compensation term through a low-pass filter, and determining a corrected flux component value by comparing the flux compensation term with a flux value obtained from a look-up table, wherein the low-pass filter receives operating parameters based on data regarding an operating environment of the motor system. The method then further determines a corrected torque value based on the corrected flux component value.

Method for online direct estimation and compensation of flux and torque errors in electric drives

A voltage saturation prevention algorithm used as at least part of a method of controlling an electric vehicle, wherein the electric vehicle comprises an electric motor, a controller, and an inverter. The controller receives a control signal with an instruction to operate the electric motor, then sends a switching signal corresponding to the control signal to the inverter, wherein the inverter provides a plurality of output signals for operation of the electric motor. The method includes determining the expected amplitude of the plurality of output signals based on the instruction to operate the electric motor, calculating the amount of modification of the plurality of output signals required to prevent the expected amplitude from reaching a saturation value, and modifying, based on the calculation, the instruction to operate the electric motor to prevent the expected amplitude from reaching the saturation value. The method is implemented in software, without any additional hardware.

Method for direct voltage saturation calculation and prevention of inverter voltage saturation

A vehicle drive system for an electric vehicle having in-hub motors configured to be independently controlled from the main traction motors. The configuration allows for robust control of the vehicle dynamics and behavior by allowing an improved powertrain control. The system also allows the vehicle to achieve better efficiencies.

Vehicle drive system

An electrical drive system for a vehicle. The system includes a plurality of electric propulsion motors and a plurality of corresponding inverter circuits. The system also includes an auxiliary motor for driving an auxiliary device located in the vehicle. The auxiliary motor is connected to the propulsion motors and is driven by the inverter circuits. The system does not include a separate inverter for driving the auxiliary motor.

Electric motor drive system for a vehicle

The present disclosure relates to systems and configurations for phase-shift autotransformers and multi-pulse rectifiers. A phase-shift autotransformer includes a wiring configuration for first, second and third magnetic cores, the wiring configuration including primary input and phase-shift windings. The primary input windings are configured to provide a first and second primary input inductances, and phase-shift windings of the wiring configuration are configured to provide multiple inductances for each phase-shift winding. A multi-pulse rectifier is provided including a phase-shifting autotransformer, a diode bridge rectifier configuration coupled to output of the autotransformer and a filtering capacitor coupled to the diode bridge rectifier. Other embodiments are directed to use of the multi-use rectifier system with vehicle charging station, such as an Electric Vehicle Supply Equipment (EVSE).

Phase-shift autotransformer, multi-pulse rectifier systems and fast charging

A DC link capacitor cooling system having an integrated heat sink disposed across a bottom surface of a DC link capacitor with a dielectric thermal interface material covering the integrated heat sink, and a chassis contacting the dielectric thermal interface material, wherein the chassis has an active fluid coolant domain therein.

DC link capacitor cooling system

An inverter assembly for an electric vehicle. The inverter assembly includes three inverters driving at least one wheel of the vehicle. Each inverter has a different phases angle relative to the other inverters in order to minimize current ripple and reduce the capacitor size to allow a smaller package for the inverter assembly.

Inverter system for an electric vehicle

A combined bi-directional converter and an auxiliary power module circuit for an 800V battery of an electric vehicle. The converter providing a stepped voltage of 400V with a duty ratio of 50 percent. The combined circuit comprises a high voltage side and a low voltage side. A transformer provides an interface between the high voltage side and the low voltage side. The combined circuit comprises a buck and boost mode.

Combined converter circuit

A method of controlling an electric vehicle, wherein the electric vehicle comprises an electric motor, a controller, and an inverter, wherein the controller receives a control signal with an instruction to operate the electric motor. In one embodiment, the method includes collecting an operational data set on a plurality of output signals of the inverter and a rotation angle of the electric motor. In one embodiment, the method includes computing a voltage change of the inverter and a magnetic flux of the electric motor based on a predetermined data set and the operational data set. In one embodiment, the method includes adjusting an output of the inverter to offset the voltage change and the magnetic flux, the output being provided to the electric motor to control the electric motor in accordance with the instruction.

Polar method for electric motor software calibration considering inverter voltage loss

A sleep-wake control circuit using a D-type flip-flop with a Schmitt trigger to detect pulse wake-up signal transitions. The sleep-wake control circuit comprises a sleep command input channel, a wake command input channel, and a D-type flip-flop. The D-type flip-flop is configured to receive a signal to switch to sleep mode from the sleep command input channel as a clock signal and to receive a wake event signal to switch to wake mode from the wake command input channel as a clear signal, such that a wake event signal from the wake command input channel takes priority over a sleep event signal from the sleep command input channel. The sleep command input channel and the wake command input channel are configured to include Schmitt triggers so as to detect pulse input signals.

Sleep-wake control circuit for battery powered electronic device

A switched reluctance motor for an electric vehicle. The switched reluctance motor includes an inverter with switchable windings to control the inductance of the motor. The motor also includes a high speed and low speed mode corresponding to the inductance of the motor. The inverter may include parallel switches, selectively running current to the windings in order to control the inductance.

Switched reluctance motor control

A segmented electrical drive system comprising a DC power bus comprising a DC voltage supply and a capacitor in parallel, an inverter comprising a plurality of inverter segments, a motor including a plurality of stator winding segments each connected to an inverter segment, and a controller. The controller receives a control signal and sends a switching signal to each of the inverter segments, wherein the switching signal is based on a discontinuous space vector pulse width modulation (DSVPWM) scheme for a segmented inverter. The DSVPWM scheme includes a set of reverse sawtooth carrier signals that are at an optimal phase shift angle with respect to each other.

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Irvine, CA, United States of America

Geng Niu