Ford Global Technolgoies, LLC

Jiyao Wang

Wei Xu

Silong Li

Michael W Degner

Zhichun Ma

Shuzhen Liu

Yang Xu

Xuemei Sun

Yinghan Xu

Hongjie Wu

William Reynolds

Joseph Sherman Kimmel

Yingfeng Ji

Felicia Sun

Wenbo Liu

Systems and methods for operating an electric drive system for an electric or hybrid vehicle is described. In one example, the drive system is operated by suppling a pulsed torque current command while supplying a zero flux current command. The torque current command and the flux current command make up winding current commands for an electric machine.

Methods and system for estimating electric machine position offset

An electric machine includes a rotor and a stator. The rotor is configured to generate rotational motion. The stator is disposed radially about the rotor. The stator has a core and windings. The core defines a first array of orifices about an inner diameter of the core and a second array of orifices radially outward from the first array of orifices. The windings are disposed within the first array of orifices. A magnetic material is configured to advance into and retract from the second array of orifices to adjust a magnetic flux within an airgap defined between the rotor and the stator.

Electric machine and control system for a vehicle powered by the electric machine

A vehicle includes an electric machine, a battery, an inverter, and a controller. The controller switches the inverter at a switching frequency selected to generate an AC current to heat the battery, adjusts a d-axis current of the electric machine to increase a battery heating power, and adjusts a q-axis current of the electric machine according to the adjusted d-axis current.

System and method for resonant heating battery

A system for controlling an electric machine of a vehicle includes, among other things, a controller module configured to attenuate noise from the electric machine by altering a corrective voltage in response to feedback about the noise. The corrective voltage and a fundamental voltage command are supplied to the electric machine as a combined voltage command. The corrective voltage is on a harmonic adjacent to a harmonic of the noise. A method of controlling noise associated with an electric machine of a vehicle includes, among other things, altering a corrective voltage to attenuate noise in response to feedback about the noise. The corrective voltage and a fundamental voltage command are supplied to the electric machine as a combined voltage command. The corrective voltage is on a harmonic adjacent to a harmonic of the noise.

Electric machine noise attenuation

A control method includes sequentially updating a next cycle pulse width modulation command for each of an upper switch and lower switch of a phase leg of a power converter according to an order defined by timing of a rising edge of the next cycle pulse width command for one of the switches relative to a rising edge of a previous cycle pulse width command for the one of the switches.

Dynamic pulse width modulation update

A vehicle includes an electric machine having a number of pole pairs, N, a position sensor having a number of pole pairs, M, that generates output indicative of a rotational position of the electric machine, and one or more controllers. The one or more controllers generate a remapped rotational position according to a product of the rotational position and L/N, generate a scaled position according to a product of the remapped rotational position and N/M, and command the electric machine to produce a specified torque or speed based on the scaled position. M is not equal to and not a factor of N, and L is a minimum common multiplier of N and M.

Detection and control of electric machine with any combination of position sensor number of pole pairs and electric machine number of pole pairs

A vehicle power system includes a battery bus between a traction battery and voltage converter, a high-voltage bus between the voltage converter and an inverter, and a controller. The controller, responsive to a contactor between the traction battery and voltage converter opening, controls an engine to maintain a speed of a generator electrically coupled with the inverter within a predefined range, controls the voltage converter to drive a measured voltage of the battery bus toward a first commanded value based on a first difference between the first commanded value and measured voltage of the battery bus, and controls the generator to drive a measured voltage of the high-voltage bus toward a second commanded value different than the first commanded value based on the first difference and a second difference between the second commanded value and the measured voltage of the high-voltage bus.

DC bus voltage regulation in automotive vehicle during contactor open events

A vehicle includes a traction battery, an inverter, and a controller. The inverter includes a plurality of pairs of switches. Each of the pairs includes an upper switch that is directly electrically connected with a positive terminal of the traction battery and a lower switch that is directly electrically connected with a negative terminal of the traction battery. The controller, responsive to presence of a fault condition and during each of consecutive switching periods, deactivates all of the switches for a predetermined portion of the switching period, activates only the upper switches for another predetermined portion of the switching period, deactivates all of the switches for yet another predetermined portion of the switching period, and activates only the lower switches for still yet another predetermined portion of the switching period.

Alternating passive rectification and 3-phase-short control for motor fault protection

An electric drive system has a motor including a rotor, an inverter, and a controller. The controller perturbs a position of the rotor via a pulse width modulation (PWM) command to the inverter such that the motor receives an Id current that changes during the perturbing and an Iq current, and responsive to the Iq current settling at zero during the perturbing, alters the PWM command to cause the rotor to rotate.

Vehicle electric motor closed-loop position holding control

In an electrified vehicle having a synchronous traction motor, an inverter is connected to stator windings by three power cables. If these cables are accidentally connected to the wrong windings, the resulting torque will not match the desired torque, and may even be in the wrong direction. To avoid this problem, a test is performed any time that the cables may have been unplugged and re-connected. The inverter is commanded to generate a rotating magnetic field while the rotor is held stationary, resulting in a positive and a negative response current. A relationship between a phase angle of the negative response current and the rotor position indicates which cables are connected to which windings. If the cables are incorrectly connected, the controller disables the motor and informs an operator which cables to swap to achieve correct connection.

Hybrid transmission wiring verification

A vehicle power system includes an electric machine, an inverter electrically connected with the electric machine, and a controller. The controller, while injecting AC voltage output by the inverter into the electric machine as a DC voltage input to the inverter changes, drives a duty ratio of the inverter toward a constant value to obtain resolver offset information associated with the electric machine from a current response of the electric machine to the AC voltage.

Constant duty ratio high frequency voltage injection-based resolver offset detection

A vehicle includes a controller programmed to, responsive to injecting a high frequency voltage signal to an electric machine, determine an estimated negative sequence current phase associated with an electric machine current, and responsive to a rotor of the electric machine being at a predetermined rotor position, inject a pulse torque command to the electric machine and observe a speed change of the electric machine to determine a cable sequence.

High frequency voltage injection-based cable swap detection

An electric machine assembly for a vehicle is provided. The electric machine is in operational communication with a traction battery and includes a stator core defining a cavity and a rotor disposed within the cavity having an inner region defined by sets of triangle-shaped holes tessellated about respective central regions to form a truss structure such that the holes of the truss structure, during operational rotation, do not influence magnetic flux paths generated by magnets of the rotor. The rotor may have a strain energy value less than or equal to 16,100 Joules. The truss structure may include pairs of symmetrical portions each including segments arranged with adjacent rotor portions to define the triangle-shaped holes.

Rotor structure for electric machine assembly

A vehicle includes an electric machine. The vehicle includes a controller configured to repeatedly adjust power outputs for the two inverters so that they differ to drive the difference toward zero and such that power provided to the electric machine satisfies demand until the difference falls below a second predetermined threshold. The controller may be configured to adjust responsive to a temperature difference between two inverters associated with the electric machine exceeding a predetermined threshold.

Variable inverter output

Systems and methods for operating an inverter that is electrically coupled to a battery and an electric machine that provides propulsive force to vehicle are described. The systems and methods may selectively adjust a duty cycle of an inverter transistor responsive to battery voltage and a dead time between when a first transistor is deactivated and when a second transistor is activated.

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Canton, MI, United States of America

Jiyao Wang