System and method for propulsion system control

Abstract

A method and system for controlling a vehicle that includes a first propulsion system with a first torque generator and coupled to a first drive member, a second propulsion system with a second torque generator and coupled to a second drive member. The method includes measuring a speed of the first drive member, estimating a speed of the first drive member using a model of the first propulsion system that includes a modeled first rotational inertia and a modeled first translational inertia that are rigidly connected to each other and a model of a first coupling between the modeled first propulsion system and a model of the second propulsion system, and comparing the measured speed of the first drive member to the estimated speed of the first drive member.

Description

FIELD[0001]The present disclosure relates to a system and method for propulsion system control.INTRODUCTION[0002]This introduction generally presents the context of the disclosure. Work of the presently named inventor, to the extent it is described in this introduction, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against this disclosure.[0003]Some vehicles include multiple prime movers which may be selectively operated to motivate a vehicle. For example, a hybrid vehicle may include an internal combustion engine and an electric motor / generator that may each be selectively operated to adapt to various demands and conditions. The prime movers may selectively apply torque to drive members via a driveline.[0004]One example of a hybrid vehicle is disclosed in, commonly assigned, U.S. Pat. No. 6,953,409, which is incorporated herein by reference in its entirety. The hybri...

AI Technical Summary

Benefits of technology

The invention provides a better solution for controlling multiple drive propulsion systems in a vehicle. This solution reduces or eliminates issues like driveline vibrations, lash, and other damage to components. It simplifies the control and reduces complexity, calibration workload, and processing and component costs. In summary, the invention simplifies the way vehicles with multiple drive propulsion systems work.

Problems solved by technology

Therefore, this model is not sufficient for vehicles having more than one drive member.

There are at least two problems with such an alternative.

The first problem is that the conventional model only includes a single drive member.

If each of these separate propulsion systems include their own independent control systems, a conflict may arise.

This would result in an incorrect estimate of the speed of the drive member in that second propulsion system and incorrect control of that system would result.

However, the complexity of such a system is enormous.

Processing capacity is not infinite and can be expensive.

Additionally, each of these values must be calibrated which can significantly adversely increase the workload required to generate those calibrated values.

Additionally, the inventor realized that the complexity of such a system may quickly become unwieldy.

Further, while it is possible to use the conventional single wheel speed estimate models to represent the speed of multiple wheels using a lumped vehicle mass, such a model would not provide accurate predictions because each wheel or drive member may have different tractive efforts that correspondingly effect the speeds of each of those drive members.

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