E-compressor Speed Control for E-cat Light-off
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Solution Overview
Problem
Existing engine systems face challenges in quickly reaching the light-off temperature of catalytic treatment devices after a cold start, leading to ineffective emission reduction during this period.
Innovation Solution
A method involving an E-compressor with a controllable electric motor to regulate air supply to the E-cat, adjusting speed in response to temperature changes, allowing for precise control of catalyst heating and rapid heat-up, combined with a controller to manage the system's operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If a secondary air pump (SAP) and E-cat are activated before engine start to pre-heat the catalyst, then the catalyst can reach light-off temperature faster, but the system complexity and control difficulty increase due to the need for sensors and control logic schemes
Solution Approach 1:
The E-compressor is activated before engine start to pre-heat the E-cat catalyst, delivering compressed air through the catalyst to distribute heat from the electrical heater. This preliminary action ensures the catalyst reaches light-off temperature faster when the engine actually starts, reducing emissions during the critical warm-up period.
Solution Approach 2:
The control system monitors E-cat temperature and adjusts E-compressor speed accordingly. When the catalyst reaches the target temperature range, the compressor speed is reduced or stopped, preventing unnecessary energy consumption and optimizing the heating process dynamically.
2Speed
If the E-compressor speed is increased to deliver more air to the E-cat for faster heating, then the catalyst heats up quicker, but energy consumption increases
Solution Approach 1:
The E-compressor speed is made variable rather than fixed. The control system dynamically adjusts the compressor speed based on real-time E-cat temperature measurements, increasing speed when heating is needed and reducing speed when the target temperature is approached, optimizing the balance between heating speed and energy consumption.
Solution Approach 2:
The system changes the operating parameters of the E-compressor based on temperature conditions. By adjusting compressor speed as a variable parameter in response to temperature feedback, the system achieves efficient heating without excessive energy consumption.
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
This approach enables the E-cat to reach its light-off temperature more quickly, improving emission reduction effectiveness during cold starts by accurately controlling air flow and heat distribution.
Implementation Method 1
an electrical heating device proximate the catalyst... activating the electrical heating device of the E-cat... as the electrical heating device heats the catalyst
Implementation Method 2
an E-compressor comprising a compressor operably coupled with an electric motor for rotatably driving the compressor... activating the E-compressor to supply air to the E-cat
Implementation Method 3
catalytic treatment devices are effective for reducing emissions... An E-cat comprises a catalyst arranged in close proximity to an electrical heater... effective at reducing emissions of the exhaust gases
Data Source
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AI summary
In an internal combustion engine system having an emissions control system including an electrically heated catalyst (E-cat) and an E-compressor (either standalone or part of an E-turbocharger), a method for operating the emissions control system includes predicting that a cold start of the engine is imminent, activating the E-cat and the E-compressor in response to the prediction, and monitoring a characteristic parameter Pe of the E-cat as it changes. The E-compressor speed Nc is regulated to change in proportion to the changing Pe while the E-cat is activated. If no engine start occurs, the E-cat is deactivated, and speed Nc is regulated to track the changing Pe.