E-Machine Calibration Drift for Hydraulic Leakage Prognostics

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Hydraulic systems in off-highway applications face downtime and reduced productivity due to leakage caused by high pressure and mechanical design issues, which existing technologies have not effectively addressed.

Innovation Solution

A hydraulic system that includes an electronic machine (e-machine) with processing circuitry to generate and compare calibration data over time, determining fluid degradation by detecting differences in torque and current profiles, allowing for early detection of leakage and fluid quality decline without external sensors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If hydraulic systems operate at high pressure, then power transmission capability is improved, but leakage increases and system reliability deteriorates

Engineering Contradiction:
Improvepower transmission capabilityVSAvoidsystem reliability
Core Design Contradiction:
PowerVSReliability

Solution Approach 1:

The system performs preliminary calibration of the e-machine at a first time to establish baseline performance characteristics. This preliminary action enables future comparison to detect degradation before it causes system failure, allowing proactive maintenance that prevents reliability deterioration while maintaining high pressure operation

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system continuously monitors e-machine calibration data over time and compares it against the baseline calibration. This feedback mechanism detects fluid degradation and leakage early, enabling the system to maintain reliability by triggering maintenance alerts before high pressure operation causes catastrophic failure

Inventive Principle:
Principle #23Feedback

2Device complexity

If traditional hydraulic systems are used, then simplicity is maintained, but leakage and downtime increase due to mechanical design limitations

Engineering Contradiction:
Improvesystem simplicityVSAvoiduptime and productivity
Core Design Contradiction:
Device complexityVSProductivity

Solution Approach 1:

The patent replaces traditional mechanical hydraulic drive systems with an electronic machine (e-machine) that can be precisely controlled and monitored. This substitution enables electronic monitoring of calibration data to detect fluid degradation, reducing leakage and downtime while maintaining acceptable system complexity through integrated electronic control

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The e-machine performs self-calibration and self-monitoring by comparing its own performance characteristics over time. This self-service capability enables the system to detect its own degradation without external sensors or complex additional monitoring equipment, maintaining simplicity while improving productivity through early leakage detection

Inventive Principle:
Principle #25Self-service

3Measurement precision

If external sensors are added to detect fluid degradation, then detection accuracy is improved, but device complexity and cost increase

Engineering Contradiction:
Improvefluid degradation detection accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The e-machine uses its own internal calibration data as the sensing mechanism. By monitoring changes in its performance characteristics (current, torque, speed relationships) over time, the system detects fluid degradation without requiring external sensors. This self-service approach maintains measurement precision while minimizing device complexity

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The e-machine serves multiple functions: it provides power transmission, performs self-calibration, and acts as its own sensor for detecting fluid degradation. This multi-functionality eliminates the need for separate sensing equipment, achieving accurate detection while keeping the system simple by reusing existing components

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

Data Source

PatentEP4450834A1Prognostics in hydraulic transmission system using e-machine drive
Publication Date: 2024.10.23 DEERE & CO
  • EP4450834A1 patent drawingFigure 1~2
  • EP4450834A1 patent drawingFigure 3
  • EP4450834A1 patent drawingFigure 4

AI summary

A device for determining fluid degradation includes a memory and processing circuitry configured to cause the device to generate first calibration data of an e-machine at a first time, generate second calibration data of the e-machine at a second time subsequent to the first time, and determine that the fluid is degraded in response to a difference between the first calibration data and the second calibration data being greater than or equal to a degradation threshold.