Tula Technology, Inc.

Cummins Inc.

Tula Etechnology, Inc.

Xiaoping Cai

Louis Joseph Serrano

Shikui Kevin Chen

Avra Brahma

Andrew W Phillips

Vijay Srinivasan

Benjamin M Wolk

Justin R Lee

J Steven Kolhouse

Xin Yuan

Adrian P Dale

Xi Luo

Aditya Mandal

Robert C Wang

Yongyan Cao

Louis Joe Serrano

Andrea Marie Evans

Kevin Shikui Chen

A method of controlling an electric motor to optimize system efficiency of an electric motor operable in a pulsed mode and a continuous mode is disclosed herein. The method includes receiving a requested torque for the electric motor, calculating a pulsed system efficiency, calculating a continuous system efficiency, and operating the electric motor in the pulsed mode when the pulsed system efficiency is greater than the continuous system efficiency. The pulsed system efficiency is calculated for delivering the requested torque from the electric motor in a plurality of torque pulses greater than the requested torque. The continuous system efficiency is calculated for delivering the requested torque from the electric motor as a continuous torque. The system efficiency may be at least partially based on a battery efficiency and a motor efficiency.

Method of optimizing system efficiency for battery powered electric motors

A variety of methods and arrangements are described for managing recharging of cylinders of an internal combustion engine during skip fire operation of the engine. In one method, a maximum allowed deactivation time for a cylinder is determined and the cylinder is recharged before the maximum allowed deactivation time is exceeded.

Recharging management for skipping cylinders

A system and method for operating an ICE by (a) generating a running history of one or more-cylinder events per cylinder, and (b) using the running history to select a least-used non-rotating firing pattern, among a plurality of non-rotating firing patterns, provided for each firing fraction less than one (1). By making the least used selection based on the running history, unequal usage among cylinders of the ICE can be mitigated.

Non-rotating cylinder pattern selection for equalizing cylinder usage in an internal combustion engine

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 system and method for transitioning a firing fraction of a variable displacement internal combustion engine when generating a desired torque output. During and following the transition to the second firing fraction, a combustion recipe is ascertained and used operating the cylinders of the variable displacement internal combustion engine to generate the desired torque output. The recipe is preferably optimized for the engine operating at the second firing fraction, at least relative to the previous charge of the previous combustion recipe used with the first firing fraction.

Optimizing combustion recipes to improve engine performance and emissions for variable displacement engines

Managing firing fraction transitions of a variable displacement internal combustion engines by (a) avoiding transport delays in an Exhaust Gas Recirculation (EGR) feed by starting movement of an EGR valve position after a decision to transition to a new firing fraction has been made, but prior to the start of the transition and (b) adjusting the EGR valve as needed during the transition so as to maintain an EGR fraction within a predetermined range during the transition. By performing both (a) and (b), spikes of nitrous oxide (NO) and/or hydrocarbon emissions are reduced or altogether eliminated during the transition.

Exhaust gas recirculation flow control for reducing emissions with variable displacement internal combustion engines

A system and method for the use of machine learning for detecting faults for cylinder intake and/or exhaust valves that do not properly open or close as commanded and for generating a flag for such faults.

Use of machine learning for detecting cylinder intake and/or exhaust valve faults during operation of an internal combustion engine

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

A system and method for transitioning a firing fraction of a variable displacement internal combustion engine when generating a desired torque output. During and following the transition to the second firing fraction, a charge of a combustion recipe is ascertained and used operating the cylinders of the variable displacement internal combustion engine to generate the desired torque output. The charge is preferably optimized for the engine operating at the second firing fraction, at least relative to the previous charge of the previous combustion recipe used with the first firing fraction.

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.

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Fremont, CA, United States of America

Xiaoping Cai