Electric Machine Torque Assist for Wheel Loader Hydraulic Transients
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wheel loaders face challenges in managing sudden rapid increases in load on the working hydraulic system, leading to potential engine stalling and reduced performance, as existing solutions either overburden the combustion engine or diminish hydraulic system efficiency.
Innovation Solution
A method and system that detect operational parameters indicative of hydraulic load increases, determining if additional torque is needed, and using an electric machine to add torque to the transmission line, thereby reducing the load on the power source without compromising hydraulic system performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the combustion engine runs at higher rotational speeds to provide power margin for sudden load increases, then the ability to meet transient load increases is improved, but fuel consumption increases significantly
Solution Approach 1:
The electric machine is activated in advance or immediately upon detection of a transient load increase on the hydraulic system, providing torque to the transmission line before the combustion engine can respond. This preliminary action allows the engine to operate at lower speeds during normal conditions while still meeting peak demand during transients.
Solution Approach 2:
The electric machine acts as an intermediary between the hydraulic system and the combustion engine. It detects load increases on the hydraulic system and provides compensating torque to the transmission line, mediating the interaction between the hydraulic demand and engine supply, thereby allowing the engine to operate more efficiently.
2Use of energy by moving object
If the combustion engine runs at lower rotational speeds to reduce fuel consumption, then energy efficiency is improved, but the power margin for sudden load increases is significantly reduced
Solution Approach 1:
The electric machine serves as a mediator that detects transient load increases on the hydraulic system and provides compensating torque to the transmission line, allowing the combustion engine to operate at lower, more efficient speeds while still meeting peak power demands.
Solution Approach 2:
The system changes the operational parameters by introducing an electric torque source that can rapidly adjust its output based on detected hydraulic load conditions. This allows the engine to operate at optimized lower speeds while the electric machine compensates for power deficits during transient conditions.
3Speed
If larger hydraulic pumps with higher displacement are used to ensure fast hydraulic functions at lower rotational speeds, then hydraulic performance is improved, but the torque load on the combustion engine increases
Solution Approach 1:
The electric machine acts as an intermediary torque source that compensates for the increased torque demand on the combustion engine caused by larger hydraulic pumps. It detects transient load increases and provides additional torque to the transmission line, reducing the burden on the engine.
Solution Approach 2:
The patent replaces part of the mechanical torque transmission system with an electric torque provision system. Instead of relying solely on the combustion engine to provide all torque, an electric machine is introduced to provide torque to the transmission line, substituting mechanical engine torque with electric torque during transient conditions.
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 wheel loaders to effectively manage transient load increases without overburdening the combustion engine or reducing hydraulic system performance, ensuring stable operation and efficient power management.
Implementation Method 1
adding torque in case additional torque is determined to be needed by an electric machine arranged to add torque to the transmission line
Data Source
AI summary
A working machine (1 ) and a method for operating a working machine (1 ) comprising a power source (120) and a plurality of driving wheels (130); a working hydraulic system (140) comprising at least one hydraulic pump (142, 144, 146) powered by the power source (120) for moving an implement (3) on the working machine (1 ) and/or for steering the working machine (1 ); a transmission line (110) arranged between the power source (120) and the driving wheels (130) for transmitting torque from the power source (120) to the driving wheels (130). The method is characterized by the steps of: detecting at least one operational parameter indicative of a load exerted on the working hydraulic system (140), determining if torque needs to be added, in addition to a torque delivered by the power source (120), on the basis of a magnitude of the detected operational parameter in order to reduce the a load on the power source (120), and adding torque in case additional torque is determined to be needed.