Inverter-Assisted Exhaust Heating for Catalyst Temperature Control

Solution Overview

Problem

Existing exhaust aftertreatment systems face challenges in maintaining temperature-sensitive catalysts at desired operating temperatures, leading to underperformance and increased emissions, with conventional heating methods suffering from fuel economy, parasitic losses, power availability, reliability, and system complexity issues.

Innovation Solution

An inverter-based thermal management system utilizing an inverter module with phase legs and an auxiliary leg to provide heating to temperature-sensitive catalysts in the exhaust aftertreatment system, leveraging energy from an electric machine and energy storage system to regulate temperature effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If conventional heating methods (fuel injection or electrical heating) are used to maintain catalyst temperature, then catalyst operating temperature is improved, but fuel economy and system complexity worsen

Engineering Contradiction:

Improvecatalyst operating temperatureVSAvoidfuel economy

Core Design Contradiction:

TemperatureVSUse of energy by moving object

Solution Approach 1:

The patent converts the harmful waste heat from the electric machine/inverter into a beneficial heating source for the catalyst. The inverter, which normally dissipates power as heat during operation, is repurposed to provide controlled heating to the aftertreatment system, transforming a waste product into a useful resource that maintains catalyst temperature without consuming additional fuel.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The inverter is given a dual function: its primary function for power conversion is maintained, and it simultaneously serves as a heating source for the aftertreatment system. This multi-functionality eliminates the need for separate heating systems, reducing overall system complexity while improving fuel economy.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Temperature

If conventional heating methods (fuel injection or electrical heating) are used to maintain catalyst temperature, then catalyst operating temperature is improved, but system complexity worsens

Engineering Contradiction:

Improvecatalyst operating temperatureVSAvoidsystem complexity

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The inverter is given a dual function: its primary function for power conversion is maintained, and it simultaneously serves as a heating source for the aftertreatment system. This multi-functionality eliminates the need for separate heating systems, reducing overall system complexity while improving fuel economy.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The heating function is merged with the existing inverter system rather than being implemented as a separate component. By combining the heating capability with the power conversion system, the patent reduces the number of discrete components and simplifies the overall system architecture.

Inventive Principle:

Principle #5Merging (Combining)

3Temperature

If in-cylinder or post-cylinder fuel injection is used to generate heat, then catalyst temperature is improved, but parasitic losses and power availability worsen

Engineering Contradiction:

Improvecatalyst temperatureVSAvoidpower availability

Core Design Contradiction:

TemperatureVSPower

Solution Approach 1:

The patent converts the harmful waste heat from the electric machine/inverter into a beneficial heating source for the catalyst. The inverter, which normally dissipates power as heat during operation, is repurposed to provide controlled heating to the aftertreatment system, transforming a waste product into a useful resource that maintains catalyst temperature without consuming additional fuel.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The system efficiently maintains catalyst temperatures within desired ranges, improving performance and reducing emissions while optimizing energy use and system reliability.

Implementation Method 1

one or more electrical heating elements thermally coupled with the one or more components exhaust aftertreatment system

Methodology Applied

Scientific EffectJoule heating: Joule Heating

Data Source

PatentEP3873782B1Inverter-based exhaust aftertreatment thermal management apparatuses, methods, systems, and techniques

Publication Date: 2025.10.15 CUMMINS INC

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AI summary

One exemplary embodiment is a vehicle system comprising an engine, an exhaust aftertreatment system including a heating element, an electric machine configured to selectably operate as a motor or a generator, an inverter module including a plurality of inverter phase legs and an auxiliary leg, and an electronic control system in operative communication with the inverter module and the exhaust aftertreatment system. The electronic control system is configured to evaluate whether the electric machine is operating as a generator, selectably operate the plurality of inverter phase legs to rectify AC power received from the electric machine, evaluate whether to heat one or more components of the exhaust aftertreatment system, and selectably operate the auxiliary leg to provide rectified power from the inverter legs to one or more electrical heating elements thermally coupled with the one or more components exhaust aftertreatment system effective to heat the one or more components.