Gm Global Technology Operations LLC

Tula Technology, Inc.

Other

Dana Corporation

Tula Etechnology, Inc.

Andrew W Phillips

James M Hart

Scott H Wittkopp

Clinton E Carey

Madhusudan Raghavan

Edward W Mellet

Edwin T Grochowski

James B Borgerson

Gregory Hukill

Elizabeth I Wooden

Louis Joseph Serrano

Donald L Dusenberry

Xiaoping Cai

Shawn Harold Swales

Steven Patrick Moorman

Craig S Ross

Joel M Maguire

Steven E Carlson

Daryl A Wilton

Shikui Kevin Chen

Xin Yuan

Vijay Srinivasan

Mark A Wilcutts

John E Marano

Siamak Hashemi

Srihari Kalluri

Jeffrey Kenneth Baran

Vijay A Neelakantan

Brendan M Conlon

Matthew Aaron Younkins

Philip C Lundberg

Shushan Bai

David S Mathews

Ronald F Lochocki, Jr

Scott Heitzenrater

Hong Yang

David W Wright

Zhe Xie

Paul Carvell

Nathaniel E Wilke

Klaus Kersting

Amanda Luedtke

Jerry F Fuschetto

John M Fuerst

A control system for an electric machine, wherein the electric machine has a maximum bus value (V) is provided. The control system is configured to determine a feedforward vector (V), determine a feedback vector (V), compare a magnitude of a sum of the feedforward vector and feedback vector (|V+V|) and the maximum bus value (V), when |V+V|≤Vproviding a control vector of V+Vto the electric machine, and when |V+V|>Vproviding a control vector of V+k(V) to the electric machine, where k is a scalar value between 0 and 1 inclusive where |V+k(V)|=V.

Feedback scaling for electric machines

Methods and controllers for controlling engine speed to reduce NVH that occurs in conjunction with transmission shifts are described. In some embodiments, when a transmission shift to a target gear is expected, a target engine speed appropriate for the target gear is first determined. A target rate of change of the engine speed is calculated from the initial engine speed and target engine speed in conjunction with a target transition time. A target torque is then calculated from the target rate of change of engine speed. A target firing fraction or induction ratio are determined that are desired for use with the target engine speed based on the target torque. The transition to the target engine speed and target firing fraction or induction ratio are completed before the gear shift is completed. The described approaches are well suited for use during skip fire or other cylinder output level modulation operation of the engine.

Managing engine firing fraction changes during gear shifts

A method of controlling an electric motor includes receiving a duty cycle for the electric motor for delivering a target torque from the electric motor, generating a pulse train, and pulsing the electric motor with the generated pulse train. Generating the pulse train being at least partially based on the received duty cycle. The generated pulse train optimized to improve at least one of noise, vibration, or harshness of the electric motor when compared to a constant pulse frequency.

Methods of optimizing waveforms for electric motors

Controllers and methods for managing transitions into and/or out of a cylinder cut off mode are described. In some embodiments, a skip fire based transition into a cylinder cut off mode is used in which the fraction of working cycles that are fired is gradually reduced to a threshold firing fraction. Once the threshold firing fraction has been reached, all of the working chambers are deactivated.

Deceleration cylinder cut-off

A skip fire engine controller is disclosed that commands an early direct-injection of fuel during a skipped working cycle in which a cylinder is not exhausted. With early direct injection, the fuel has more time to vaporize and mix with air for combustion in an immediately following working cycle in which the cylinder is fired. By increasing the degree of vaporization and mixing, the combustion is both cleaner and more efficient.

Early direct fuel injection for internal combustion engines

Methods and controllers for coordinating firing fraction transitions that occur in conjunction with transmission shifts are described. In one aspect, an engine controller transmits a do-not-shift instruction to a transmission controller based at least in part on a determination that a particular type of firing fraction transition is desired. The firing fraction transition is then implemented using a skip fire transition protocol. In this manner, the transmission is affirmatively prevented from shifting during the firing fraction transition. The described approaches are well suited for use in connection with transitions to DCCO or DFCO operation.

Managing engine firing fraction changes

Methods and controllers for coordinating firing fraction transitions that occur in conjunction with transmission shifts are described. In some embodiments, when a transmission shift to a target gear is expected, a target firing fraction is determined that is desired for use after the shift has completed. In selected circumstances, the change to the target firing fraction is initiated prior to the shift to the target gear. The transition to the target firing fraction preferably completes before an inertia/speed phase of the shift. In other embodiments, the engine transitions to all cylinder operation or other suitable transitional firing fraction in response to an expected transmission shift. After the shift completes, a transition is made to a target firing fraction. The described approaches are well suited for use during skip fire or other cylinder output level modulation operation of the engine and are particularly beneficial during up-shifts.

Methods and arrangements for transitioning an engine between a deceleration cylinder cutoff (DCCO) state and an operational state are described. In one aspect, transitions from DCCO begin with reactivating cylinders to pump air to reduce the pressure in the intake manifold prior to firing any cylinders. In another aspect, transitions from DCCO, involve the use of an air pumping skip fire operational mode. After the manifold pressure has been reduced, the engine may transition to either a cylinder deactivation skip fire operational mode or other appropriate operational mode. In yet another aspect a method of transitioning into DCCO using a skip fire approach is described. In this aspect, the fraction of the working cycles that are fired is gradually reduced to a threshold firing fraction. All of the working chambers are then deactivated after reaching the threshold firing fraction.

A front wheel drive or rear wheel drive continuously variable transmission is provided having an input shaft, an output shaft, a continuously variable tilting ball planetary variator, a compound planetary gearset assembly having first, second, third, and fourth rotating elements, and a plurality of torque transmitting devices. The compound planetary gearset assembly has a simple single pinion gearset and a compound double pinion gearset, having fixedly connected planetary carriers and fixedly connected ring gears, creating a joint planetary gear carrier and joint ring gear. The outer planetary gears engage the ring gear which drives the output shaft. Selective torque transmitting devices include clutches and braking clutches.

3-mode front wheel drive and rear wheel drive continuously variable planetary transmission

Arc coil springs utilize coil spring wire formed in a substantially trapezoidal or other shape such that when bottomed, the side surfaces of the coil abut and carry the bottoming load. The angles of the sidewalls of the substantially trapezoidal cross section wire are preferably coincident with lines of radius when the spring is installed in an arc in a clutch, damper or flywheel. The radius of the outer surface of the arc coil spring wire is matched to the radius of the inner surface of the guide or housing so that the area of contact is large.

Arc coil spring configuration

A system according to the principles of the present invention includes a firing fraction module, an offset generation module, and a firing fraction module. The firing fraction module determines a firing fraction based on a driver torque request. The offset generation module randomly generates an offset. The firing control module adds the firing fraction to a running total each time that a crankshaft of an engine rotates through a predetermined angle, adds the offset to the running total, and executes a firing event in a cylinder of the engine when the running total is greater than or equal to a predetermined value.

System and method for randomly adjusting a firing frequency of an engine to reduce vibration when cylinders of the engine are deactivated

A transmission is provided having an input member, an output member, four planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. Each of the planetary gear sets includes first, second and third members. The torque transmitting devices may include clutches and brakes and are selectively engageable in combinations of at least two to establish at least eight forward speed ratios and at least one reverse speed ratio between the input member and the output member.

Multi-speed transmission

A transmission has an input member, an output member, at least four planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. Each of the planetary gear sets includes first, second and third members. The torque transmitting devices include clutches and brakes actuatable in combinations of three to establish a plurality of forward gear ratios and at least one reverse gear ratio.

A variety of methods and arrangements for determining conditions when an engine-decoupling friction interface may be locked-up during skip-fire operation of an internal combustion engine are described. In some embodiments, the engine-decoupling friction interface is the lockup clutch of a torque converter situated in a powertrain that transmits motive power from the engine to a wheel. Rotation of the wheel causes vehicle motion.

Torque converter clutch lockup during skip-fire operation

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Rochester, MI, United States of America

Andrew W Phillips