Dual-Motor Power Assembly Oil Path Layout for Cooling and Lubrication

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Dual-drive vehicle power assemblies face challenges in cooling and lubrication due to increased torque requirements, leading to higher copper losses, efficiency decreases, and complex cooling oil path designs, which complicate manufacturing and processing.

Innovation Solution

A power assembly with a simplified oil path design, utilizing dual oil pumps and a single heat exchanger to efficiently cool and lubricate both drive motors and speed reducers, with independent heat exchange branches and flow regulating components to maintain optimal temperature and lubrication.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If dual-drive motors and dual speed reducers are used to improve power performance, then peak torque and power output are improved, but the complexity of the cooling oil path increases significantly

Engineering Contradiction:
Improvepeak torqueVSAvoidcooling oil path complexity
Core Design Contradiction:
PowerVSDevice complexity

Solution Approach 1:

The patent merges the cooling oil paths of the first and second drive motors by using a shared heat exchanger. The oil paths are integrated such that both motors draw cooling oil from the same heat exchanger, reducing the overall complexity of the cooling system while maintaining adequate cooling for both high-power motors

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The heat exchanger is designed to serve multiple functions: it cools both the first and second drive motors, and also provides lubrication oil to both speed reducers. This multi-functional design reduces the number of separate cooling systems needed, thereby simplifying the overall oil path configuration

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Temperature

If the cooling oil path is designed separately for each motor, then cooling effectiveness is improved, but manufacturing and processing difficulty increases

Engineering Contradiction:
Improvecooling effectivenessVSAvoidprocessing difficulty
Core Design Contradiction:
TemperatureVSEase of manufacture

Solution Approach 1:

The patent combines separate cooling paths into a unified system where a single heat exchanger serves both motors. The housing integrates oil paths that distribute cooling oil from the common heat exchanger to both drive motors, reducing manufacturing steps and processing complexity while maintaining cooling effectiveness through proper oil distribution

Inventive Principle:
Principle #5Merging (Combining)

3Reliability

If dual oil pumps are used to lubricate stators and rotors separately, then lubrication precision is improved, but the integration level of oil paths decreases

Engineering Contradiction:
Improvelubrication precisionVSAvoidoil path integration
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the lubrication functions by dedicating the first oil pump specifically to stator lubrication and the second oil pump to rotor lubrication. This segmentation ensures precise lubrication delivery to each component while the overall oil path remains integrated through the housing's unified structure and shared heat exchanger

Inventive Principle:
Principle #1Segmentation

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 solution ensures effective cooling and lubrication of dual-drive motors and speed reducers, maintaining optimal performance and simplifying the internal structure of the power assembly, thereby improving the integration level and reducing manufacturing complexity.

Implementation Method 1

the heat exchanger cools the lubricating oil, and therefore, a system has functions of cooling and lubricating the stator, the rotor, and the speed reducers on both sides

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Implementation Method 2

the first oil pump can pump the lubricating oil in the oil pan into the first stator and the second stator by using the first oil path

Methodology Applied
Scientific EffectHydraulic pumping: Pump

Implementation Method 3

supply the lubricating oil to the first speed reducer and the second speed reducer for lubrication

Methodology Applied
Scientific EffectLubrication: Lubrication

Data Source

PatentEP4166819B1Power assembly and vehicle
Publication Date: 2024.05.22 HUAWEI DIGITAL POWER TECH CO LTD
  • EP4166819B1 patent drawingFigure 1
  • EP4166819B1 patent drawingFigure 2
  • EP4166819B1 patent drawingFigure 3

AI summary

This application provides a power assembly and a vehicle. The power assembly includes a housing, and a first drive motor, a first speed reducer, a first oil path, a second drive motor, a second speed reducer, a second oil path, and a third oil path that are located inside the housing. The power assembly further includes a first oil pump and a second oil pump. The housing is provided with an oil pan. The first drive motor includes a first stator and a first rotor. The second drive motor includes a second stator and a second rotor. Both the first oil pump and the second oil pump are connected to the oil pan. The first oil path is connected to the first oil pump, and is configured to supply oil to the first stator and the second stator. The second oil path is configured to supply oil to the first rotor and the second rotor. The third oil path is connected to the first oil path and/or the second oil path, so that a part of lubricating oil in the first oil path and/or the second oil path can enter the third oil path, and the oil is supplied to the first speed reducer and the second speed reducer through the third oil path. The power assembly in this application simplifies the oil paths in the housing and improve an integration level.