Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

June 5th, 2019

CCEFP Summit at Purdue in Honor of Monika Ivantysynova

Xin Tian, Josias Cruz [Presenter]

Advisor: Andrea Vacca

MAHA Fluid Power Research Center

Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling 2

Introduction

Current work

System Power Distribution Characterization

System Models Development and Validation

Experimental Tests Set Up

Contents

System Model Validation Results

Conclusion

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

Research motivation

Auxiliary hydraulic functions

Power beyond

Traveling service

Steering

Braking

Introduction Model development Experimental tests Power distribution ConclusionModel validation

Ag. Tractor Standards

Guarantee

State of The Art Architectures

Load Sensing

Competitive Machine

Operation

Optimal BehaviorAll working maneuvers?

How to know?

4

Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

Research goal

We know: Different sources of power loss existing [load sensing]

• Feasible and cost-effective solutions for significant increase of energy efficiency of such system to improve overall system efficiency.

Introduction Model development Experimental tests Power distribution CurrentModel validation

5

Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

Research approach

5

Classification of Energy Losses

Solution Proposal

Experimental Characterization

Validated AMESim Model

Machine Instrumentation

Steady State Testing

Dynamic Testing(Real Drive Cycles)

Introduction Model development Experimental tests Power distribution CurrentModel validation

6

Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

Steady State Testing

Dynamic Testing(Real Drive Cycles)

Experimental Characterization

Validated AMESim Model Testing

Solution ProposalImproved? Yes!

No

Improved?

Deliver

Yes!

No

Research approachIntroduction Model development Experimental tests Power distribution CurrentModel validation

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

Reference hydraulic circuit

Variable Displacement Load Sensing Pump

Hitch Control Valve

EHR Control Valve 1 EHR Control Valve 2

Introduction Model development Experimental tests Power distribution CurrentModel validation

8

Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

pump supply port LS signal port

CH

CH CH

System modelingVariable Displacement Load Sensing Pump

CHCH CH

CH

CH

CH

CH

CH CH

CH

Tank

Flow Compensator

Pressure Compensator

Control Piston

pump drain portlow pressure circuit port

shaft speed

Introduction Model development Experimental tests Power distribution CurrentModel validation

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

Pressure Compensator

System modeling

CH

CH CH

friction

𝐹

friction

𝐹𝑠

overlap underlap

𝑄 = 𝑐𝑞 ∙ 𝐴 ∙2 ∆𝑝

𝜌∙ 𝑠𝑖𝑔𝑛 ∆𝑝

CH𝑑𝑝

𝑑𝑡=

𝐵 𝑝 ∙ 𝑄 𝑝

𝑉 𝑝

Orifice equation:

Internal volumes:

overlapunderlap Jet forces:

𝐾 = 𝑘𝑗𝑒𝑡 ∙1

2tanh

2 𝑙𝑎𝑝 − 𝑚𝑖𝑛

𝑚𝑖𝑛+ 1

𝐹𝑗𝑒𝑡 = 𝐾 ∙ 2 ∙ 𝑐𝑞 ∙ 𝐴 ∙ ∆𝑝 ∙ 𝑐𝑜𝑠𝜃

Spool equilibrium: 𝐹 = 𝐹𝑠 + 𝐹𝑗𝑒𝑡

friction

𝑭𝒔

Viscous friction force: 𝑓 = −𝑏 ∙ 𝑣

Introduction Model development Experimental tests Power distribution CurrentModel validation

10

Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

• Pressure-flow compensator dynamic test: SAE STANDARD J745 JUN2009

Load Pressure:Model = 158.77 bar

Experiment = 159.11 bar

Standby Pressure:13.43 bar11.50 bar

Model validationIntroduction Model development Experimental tests Power distribution CurrentModel validation

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

Experimental tests set upIntroduction Model development Experimental tests Power distribution CurrentModel validation

Reference Vehicle

Hydraulic Theory

MAHA Fluid Power

Research Center

EHR Valves

MAHA Test Plan

DLG PowerMix Test

Nebraska Test

Agricultural Tractor

Testing Standards

Realistic Steady and Dynamic Tests

EHR Test Summary

Number of Tests

Single Remote 224

Multiple Remotes 48

TOTAL 272

• Maha Test plan:

– Based on real tractor testingstandards.

– Contains specific modifications forenergy consumption analysis

– Versatile & easily adjustable to largeror smaller size tractors.

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

Experimental tests set up

CE GB

FC

PC

A B

TP

LS

R E

A B

TP

LS

R E

𝒔

𝒔

𝒔 𝒔 C C

C

Introduction Model development Experimental tests Power distribution CurrentModel validation

𝐹𝑙𝑜𝑤𝑚𝑒𝑡𝑒𝑟

𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒 𝑇𝑟𝑎𝑛𝑠𝑑𝑢𝑐𝑒𝑟

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

System Model Tests

EHRHitch control valve

100% Flow CommandEHR: (Retraction/Extension, High/Low 𝑇𝑜𝑖𝑙)

HITCH: (Rising, High/Low 𝑇𝑜𝑖𝑙)

0% Load50% Load

75%Load

90% Load

90% LoadEHR: (Retraction/Extension, High/Low 𝑇𝑜𝑖𝑙)

HITCH: (Rising, High/Low 𝑇𝑜𝑖𝑙)

25% Flow command

50% Flow Command

75% Flow Command

LS pump

Load setting

Test Plan for EHR and Hitch

Introduction Model development Experimental tests Power distribution CurrentModel validation

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

System model validation results

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 20 40 60 80 100

Flo

w R

ate

Pre

ssu

re

Load setting [%]

• Different load settings• Full command• Retraction• High 𝑇𝑜𝑖𝑙

• High RPM

Single Remote Test Results Comparison

Introduction Model development Experimental tests Power distribution CurrentModel validation

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

System model validation results

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

40 50 60 70 80 90 100

Flo

w r

ate

Pre

ssu

re

Remote load setting [%]

Hitch with Single Remote Test Results Comparison

• Different load settings on remote• Hitch cylinder raising• Full command• Extension• High 𝑇𝑜𝑖𝑙

• High RPM

Introduction Model development Experimental tests Power distribution CurrentModel validation

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

System power distribution

Power Distribution Comparison Between Different Loads for Single Remote Test

Full command, Retraction, High RPM, High oil temperature

Power Distribution Comparison Between Different Loads for Dual Remotes Test

Full command, Retraction, High RPM, High oil temperature

52.64

55.99

9.42

20.33

5.56

4.37

8.25

2.99

8.74

2.11

15.40

14.21

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

75%

90%

Power distribution in the system [%]

Load

Set

tin

g [%

]

Useful power on remote TF pump

EHR local compensator EHR main spool

EHR lock check valve Back pressure and quick coupling

52.64

55.99

9.42

20.33

5.56

4.37

8.25

2.99

8.74

2.11

15.40

14.21

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

75%

90%

Power distribution in the system [%]

Load

Set

tin

g [%

]

Useful power on remote TF pump

EHR local compensator EHR main spool

EHR lock check valve Back pressure and quick coupling

29.07

13.13

0.31

11.06

4.337.19

0.75 0.61

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

75% Load 50% Load

EHR lock check valve EHR main spool

EHR local compensator Useful power on remote

Introduction Model development Experimental tests Power distribution CurrentModel validation

EHR A EHR B

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

Introduction Model development Experimental tests Power distribution CurrentModel validation

𝐸𝐻𝑅1𝑐𝑚𝑑 𝐸𝐻𝑅2𝑐𝑚𝑑 𝑄𝑝𝑢𝑚𝑝 𝑄𝐸𝐻𝑅1 𝑄𝐸𝐻𝑅2

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Analysis of Power Distribution in a Mid-Size Agricultural Tractor through Modeling

ConclusionIntroduction Model development Experimental tests Power distribution CurrentModel validation

Rationale & Motivation

Model Development

&Validation

Experimental Instrumentation

& Testing

Complete Characterization

&Technological Improvements

Thank youfor your attention!

June 5th, 2019MAHA Fluid Power Research Center

Xin Tian, Josias Cruz [Presenter]

Advisor: Andrea Vacca