Turbocharger Base Boost Estimation Using Turbine-Compressor Power Models
Solution Overview
Problem
Existing turbocharger systems struggle to accurately estimate base boost pressure, leading to overboost phenomena that can damage hardware and render the turbocharger uncontrollable due to inaccurate estimation methods that fail to account for variables like cylinder exhaust temperature, turbine discharge pressure, and compressor efficiency.
Innovation Solution
A turbocharger control device that estimates base boost pressure by using a physical model-based turbine and compressor power functions, collecting status information such as exhaust gas flow rates and temperatures to exclude the influence of the turbocharger, and performing overboost prevention by controlling the throttle valve.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If base boost pressure is estimated using a map based on engine rpm and outside air pressure, then the estimation method is simple, but the estimation accuracy is poor and cannot exclude turbocharger influence
Solution Approach 1:
The patent replaces the simple map-based estimation method with a physics-based calculation model that uses turbine power function and compressor power function. This substitution introduces thermodynamic principles and physical relationships to achieve more accurate base boost pressure estimation by accounting for exhaust gas flow rates, temperatures, and compressor characteristics.
Solution Approach 2:
The patent introduces intermediate parameters such as turbine power, compressor power, exhaust gas flow rates, and temperatures as mediators to calculate base boost pressure. These intermediate measurements serve as bridges between the available sensor data and the target parameter, enabling more accurate estimation while excluding turbocharger influence.
2Reliability
If base boost pressure exceeds target boost pressure, then the turbocharger cannot supply negative pressure to the cylinder, but this causes overboost phenomenon that can damage hardware
Solution Approach 1:
The patent performs preliminary estimation of base boost pressure using the physics-based model before overboost occurs. By calculating the actual base boost pressure excluding turbocharger influence, the system can predict potential overboost conditions and take preventive throttle control actions in advance, avoiding hardware damage.
Solution Approach 2:
The patent implements a feedback mechanism where the estimated base boost pressure is continuously monitored and compared against target values. When the estimated base boost pressure approaches or exceeds the target, the system adjusts throttle position to maintain controllability and prevent overboost damage, creating a closed-loop control system.
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
Precise estimation of base boost pressure prevents overboosting, protecting hardware and ensuring the turbocharger remains controllable by adjusting throttle settings, thereby enhancing turbo control robustness.
Implementation Method 1
a turbocharger 1 in the related art rotates a turbine 2 by exhaust gas to generate rotational force
Implementation Method 2
compressed air is supplied to a combustion chamber of an engine cylinder 5 by the compressor 4
Data Source
AI summary
Disclosed is a turbocharger control device of a vehicle and a method of estimating base boost pressure using the same. The turbocharger control device of a vehicle includes a status information collection unit for collecting real-time status information according to an operation of a turbocharger when a vehicle is operated from various types of sensors, and a control unit for precisely estimating a base boost pressure by excluding a turbocharger boost pressure from a current boost pressure through a turbine power function and a compressor power function based on a physical model based on the collected status information.