New Electromagnetic-Thermal Coupled Analyses … Electromagnetic-Thermal Coupled Analyses for Electrical Machine Design ... e.g. flow over fins, housing ... up creation of 2D/3D FEA

1 © 2013 ANSYS, Inc. October 2, 2014 ANSYS Confidential

New Electromagnetic-Thermal Coupled Analyses for Electrical Machine Design

Marius Rosu, PhD EM Lead Product Manager, ANSYS Inc.


Manoj Nagulapally - ANSYS CFD Expert, USA

Mike Slack - ANSYS CFD Expert, UK

Yang Hu - ANSYS Electromagnetics, USA

Eddie Chong - MDL CFD Expert, UK

Acknowledgments


Integrated Motor Design Flow

Magnetic and Thermal Sizing Solution

• Case Study - PM Machine Design

Hybrid CFD Solution

• Case Study – IPM Motor Design

Electromagnetic - CFD Coupled Solution

• Case Study - Traction EV Motor Design

Outline


Motor Design Flow

Initial Design Electromagnetic Components Stress/Acoustic Temperature

Workbench System wide optimization using CAD parameters

0-D System





Hybrid CFD Solution




Outline


ANSYS Inc. and Motor Design Ltd. Collaborated to build an innovative new design flow that leverages, - ANSYS expertise in magnetic sizing of electric machines - Motor Design expertise in thermal sizing of electric machines


First-Pass Integration with ANSYS Software

RMxprt Motor Design

ANSYS Mechanical

Thermal/Stress

ANSYS CFD

Maxwell 2-D/3-D Electromagnetics

Simplorer System Design

PP := 6

ICA:

A

A

A

GAIN

A

A

A

GAIN

A

JPMSYNCIA

IB

IC

Torque JPMSYNCIA

IB

IC

TorqueD2D

Motor-CAD

Thermal

+

Magnetic and Thermal Sizing


Magnetic and Thermal Design Sizing Solution • Template-based electrical machine

design

• Fast analytical calculations for popular electric machine topologies

• One-click setup for Maxwell 2D and 3D finite element Solutions

• Network analysis dedicated to thermal analysis

• Heat transfer data calculated automatically

• Detailed cooling systems & facilitates optimisation

RMxprt

Motor-CAD


RMxprt - Magnetic Sizing


RMxprt - Magnetic Sizing Electric Machines Configurations

PM Rotor Topologies

Slot Editor

Winding Editor


Housing in RMxprt – New Capability Machine

– Stator – Rotor – Shaft – Housing

– Fin – Duct – Front Cap – Rear Cap – Foot – Flange

Overall Width

Cutout Depth

Fin Thickness

Inner Diameter

Flan

ge

Diam

eter

Plat

e He

ight

Plate Thickness

Flange Thickness

Base Thickness

Base Width

Foot Width Palm Width

Shaft Height Foot Distance

Palm Height

Length Extension

Cap Thickness Ho

lder

Dia

met

er

Bear

ing

Diam

eter

Shaft Diameter

Bearing Thickness

Out

er D

iam

eter


New UDP for Thermal Field Analysis

Housing – Four different profiles – Six different fin types – Three different duct types

EndCaps


Motor-CAD – Thermal Sizing

Includes proven models for an extensive range of cooling types: TENV: Totally enclosed non-

ventilated TEFC: Totally enclosed fan

cooled Through Ventilation TE with Internal Circulating Air Open end-shield cooling Water Jackets Submersible cooling Wet Rotor & Wet Stator cooling Spray Cooling Direct conductor cooling


Motor-CAD – Thermal Analysis

• Analytical lumped circuit analysis • Combined Thermal and Flow network

analyses • Steady state thermal analysis • Complex transient duty cycle analysis


Motor-CAD Integrated Thermal FEA Solver

Motor-CAD fully integrated FEA thermal solver allows fast calibration of analytical model giving best compromise of accuracy & calculation speed


Case Study - PM Machine Design

• Electromagnetic performance calculated in RMxprt • Default housing in RMxprt has axial fins which are suitable for TEFC cooling • Geometry and power losses are exported to Motor-CAD

RMxprt - Motor CAD



• Winding also exported from RMxprt • Motor-CAD updates winding to account for

wire size available, enamel on wire and slot liner available

RMxprt - Motor CAD



Steady-State Thermal - Instantaneous simulation

Repetitive Duty Cycle Analysis - Rapid simulation



Robust Design Analysis on Thermal Sizing - Parametric analysis - Sensitivity analysis

Initial Design Selected Design





Hybrid CFD Solution




Outline


Motor-CAD Thermal Network

Equivalent thermal network of a machine can be generated based on the machine information (geometry, materials, cooling types, heat sources, etc.)

Convective heat transfer is predicted using heat transfer correlations

The accuracy of the convection is only as good as the appropriateness and validity of the correlations used in the calculation, e.g. flow over fins, housing water jacket, etc.


Hybrid Model : CFD Domain Definition Motor – Thermal-Flow Network Equivalence

Motor-CAD thermal network is imported into ANSYS Icepak

ANSYS Icepak network replaces the thermal resistances between the housing and ambient with a CFD domain

Inside the housing, the machine is modelled using Motor-CAD thermal network, whereas the convective heat transfer outside the housing is modelled using an Icepak CFD domain

The thermal network and the CFD domain are coupled together through multi-faceted cylinder housing interfaces

Thermal-Net

Flow-Net

For the current application only thermal network is used


Detailed and Hybrid Models: Comparison

Detailed Model : 2M elements Network Model : 67k elements

3D Natural Convection Simulation on Hybrid Model • Turbulent flow model • Radiative heat transfer model • Fully parallelized solver • Converged CFD solution in ~ 2 minutes


Hybrid Model: CFD Simulation Results

Flow tracks around network Nodal temperature report





Hybrid CFD Solution




Outline


More Extensive FEA/CFD

Automated ANSYS couplings speed up creation of 2D/3D FEA and CFD models to make more detailed calculations • 3D electromagnetic effects • CFD to check/calibrate flow

calculations • AC loss in winding

SpaceClaim

Maxwell

Fluent

Motor-CAD

Icepak


Electromagnetic to CFD

• RMxprt creates complete Maxwell 3D model with housing

• Icepak account for air flow and mechanical motion on CFD domain

Temperature Profile

Icepak

Icepak

Maxwell


Modeling Water Jacket Cooling Channels

Path Lines Static Pressure

Fluent


Modeling Water Jacket Cooling Channels

Temperature Profile

Distribution of coolant using different channel configurations Fluent


Comprehensive Electromagnetic and Thermal coupled design concepts are considered at different level of design adoption

• Sizing design - Rapid Virtual Prototyping where thousands of “what if’s” can be performed in seconds;

• Hybrid design - Fast investigation of various cooling systems using thermal network coupled with CFD domain

• Physics-based design - Electromagnetic-CFD coupled solution for detailed analysis

Summary

Documents

New Electromagnetic-Thermal Coupled Analyses … Electromagnetic-Thermal Coupled Analyses for Electrical Machine Design ... e.g. flow over fins, housing ... up creation of 2D/3D FEA