Waste Gate Valve Control for Turbocharger Stall Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Engine stall occurs when switching from a non-drive range to a drive range at low temperatures in high altitudes in vehicles equipped with turbocharged engines and automatic transmissions, due to reduced air intake and increased friction torque in the torque converter.
Innovation Solution
A vehicle with a turbocharger, automatic transmission, and a controller that performs valve closing control for the waste gate valve when the hydraulic fluid temperature is below a threshold, ensuring sufficient engine output torque exceeds the torque converter's friction torque by bypassing exhaust gas and increasing air suction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the vehicle uses a turbocharged engine to increase output, then engine power is improved, but air intake at idling is reduced at high altitudes, reducing output torque
Solution Approach 1:
The waste gate valve is closed in advance before the shift operation to increase air intake and engine torque, preventing engine stall when switching from non-drive to drive range at high altitudes
2Temperature
If the vehicle operates at low temperatures to maintain cooling, then thermal management is improved, but friction torque of the torque converter increases, making engine stall more likely
Solution Approach 1:
The waste gate valve is closed before the shift operation to increase engine torque, compensating for the high friction torque of the torque converter at low temperatures and preventing engine stall
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
Prevents engine stall during shifts from non-drive to drive range by increasing engine output torque through controlled waste gate valve operation, ensuring the engine's torque exceeds the torque converter's friction torque at low temperatures and high altitudes.
Implementation Method 1
the turbine is rotated by the exhaust, and the rotation of the compressor connected to this turbine increases the amount of suction air
Implementation Method 2
the rotation of the compressor connected to this turbine increases the amount of suction air
Data Source
AI summary
The valve closing control is performed to close the waist gate valve of the turbocharger when the hydraulic fluid temperature is less than the temperature threshold. By closing the waist gate valve, the output torque is increased by increasing the amount of air taken into the engine that is idling operation, to suppress the engine stall that may occur when switching from the non-driving range to the driving range.