Titelmasterformat Klicken bearbeiten ANSYS Solutions durch for Electric Drives Daniel Bachinski-Pinhal, Johannes Raitmair, Wolfgang Freiberger, Christof Gebhardt, Jochen Haesemeyer

© CADFEM 2014

ANSYS Conference & 2nd CADFEM Ireland Users’ Meeting 24th & 25th September 2015 - Engineers Ireland, Dublin

Agenda

Component & Assembly Design

System Simulations

Customized Solutions

Electromagnetic

Power train

Stretching the limits

Circuits

Automatization

Signal integrity

Behavioral models

Thermal Mechanical Fluids

© CADFEM 2014

ANSYS Workbench

© CADFEM 2014

Workflow & Process Management • Flexible • Scalable

© CADFEM 2014

• Parametrised • Reproducible

Agenda

Component & Assembly Design

System Simulations

Customized Solutions

Electromagnetic

Power train

Stretching the limits

Circuits

Automatization

Signal integrity

Behavioral models

Thermal Mechanical Fluids

© CADFEM 2014

Electric Drives – Design Process

Analytical

Electro-magnetic

Thermal

Stress & vibration

Fatigue & lifetime © CADFEM 2014

Analytical Design • Easy and fast to configure • Datasheet/specification data as input • Winding editor: Definition of winding schemes

Source: ANSYS Inc.

© CADFEM 2014

Electromagnetic Field - Full Range • High-performance software package • Uses finite element analysis (FEA)

• Static solution • Magnetostatic • Electrostatic

• Time-Dependent • Time domain (Transient) • Frequency domain (AC) • Electric, Magnetic, Electromagnetic

Source: CADFEM

• Numerical modeling • 2D(Planar, Axisymmetric) • 3D

• Motion • Linear motion • Rotational motion • (cylindrical,non-cylindrical)

© CADFEM 2014

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Electric Drives – Design Process Analytical

Electro-magnetic

Thermal

Stress & vibration

Fatigue & lifetime

© CADFEM 2014

Thermal - CHT Simulation • Losses from EM simulation used as realistic loads • Fluid flow & heat transfer in single coupled simulation • Detailed modelling of physical effects

© CADFEM 2014

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CFD – Realistic Loads • Coupling of ANSYS Maxwell with ANSYS CFD • Electromagnetic analysis computes electromagnetic power loss • Coupling to CFD for considering heat transfer by surrounding fluid

Maxwell: Power Loss

CFD: Thermodynamics

© CADFEM 2014

Thermally Induced Motor Failure • Winding overheat à most common cause of motor failure • Hot-Spots usually not accessible for measurement • Accurate simulation requires detailed winding geometry • ANSYS equivalent material data model

Acessible for sensors

Hot-Spot “inside“ structure

• Detailed simulation of piece of winding • Extraction of equivalent material data (anisotropic model)

• Objective: Reduce simulation time maintaining result accuracy

Source: CADFEM GmbH

© CADFEM 2014

Thermal – Realistic Loads • Losses from EM simulation as realistic loads • Transient and steady-state heat transfer analysis with estimated or CFD-computed heat transfer coefficients • 2D-3D interpolation

Source: CADFEM GmbH

© CADFEM 2014

Thermal – Efficient Fluid Models • Components often cooled by fluid flow • Fluid flow by detailed CFD requires computing power

Oil flow channels

• ANSYS heat pipe model with semianalytical approach

• Objective: Reduce simulation time maintaining global result accuracy • Restriction: Exact knowledge of fluid flow not of interest

Axial air flow Axial Tgradient

Source: CADFEM GmbH

© CADFEM 2014

Example: Predict Electric Motor Performance • Objective: Predict Electric Motor Performance

Maxwell

Fluent

Mechanical

• real-life operating conditions

• ANSYS Solution 200.00

16% drop in predicted performance

Torque (N)

180.00

Y1 [NewtonMeter]

• Electromagnetic loss modeling with ANSYS Maxwell and thermal effects with ANSYS Fluent • Look at further thermal and stress analysis in ANSYS Mechanical

160.00

140.00

123.75 2.00

• Value of Simulation • Magnet temperature was more than 30 K higher than assumed • Combined simulation provides more understanding of product operation © CADFEM 2014

3.00

4.00

5.00

6.00 Time [ms]

7.00

8.00

Time (ms)

Single physics simulation, assuming a magnet temperature of 22 °C 3-way Multiphysics simulation shows that the actual magnet temperature: 53 °C

Temp Depeneded Demagnetization • Temperature determined by simulation • Arbitrary value

© CADFEM 2014

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Dynamic Temperature Dependent Coupled Demagnetization • Maxwell Transient

1st thermal iteration

• 3A current pulse

• First thermal iteration on original curve

2nd thermal iteration

• Second iteration on lower level

© CADFEM 2014

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Electric Drives – Design Process Analytical

Electro-magnetic

Thermal

Stress & vibration

Fatigue & lifetime

© CADFEM 2014

Structural - Upfront Improvement • Designer level analysis • • • •

Dimensioning Robust Design Sensitivity Single physics analysis

• Standardized assessments • Workbench FKM • ANSYS nCode DesignLife workflows

• Persistent data structure • Safety through knowledge transfer • Economic usage through customization • Re-use of data

© CADFEM 2014

Source: CADFEM GmbH

Stress & Fatigue Life • Centrifugal and magnetic forces • Nonlinear contact between magnet and steel • Definition of rotor shape according to • Deformation • Stresses • Fatigue life

© CADFEM 2014

Pressfit • Geometric modeling of overlap • Numerical modeling of overlap • Easy to define • Simple variation without touching the geometry

• Nonlinear contact combined with • No additional load • Rotation speed • Thermal deformation

© CADFEM 2014

Time to Frequency Domain Force coupling

ANSYS Workbench Magnetic Field Structural Dynamics Acoustic Field

Forces

Displacements

Source: CADFEM

© CADFEM 2014

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Vibration of Rotating Electrical Machines • Automated load transfer from magnetic field analysis • Transfer of transient magnetic loads to frequency domain by DFT

• Structural dynamics simulation • Harmonic response based on magnetic forces

• Evaluation of structure borne sound

Sources: CADFEM © CADFEM 2014

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Structure Bourne Sound to Air Bourne sound • Result of Structure borne Sound Analysis: Surface Velocity • Integral of Surface Velocity = ERP = Equivalent Radiated Power

ERP = r × c0 × A × v 2 • Airborne Sound is radiated, when the Surface Waves excite Air Waves • Radiation efficiency σ is a Function of Frequency and <1 for low Frequencies [Dr. Neher, MAN Turbo &Diesel]

SPWL = r × c0 × A × v 2 × s à Airborne Sound Analysis is required to get the True Sound Power

© CADFEM 2014

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CADFEM Test & Simulation correlation solution Simulation: 1295Hz

Simulation Tests: 755Hz

Testing

Calibration

CADFEM can help Nr. Test Sim. Diff.

Opt.

Diff.

§1 Reverse Engineering Solution: 92 112 21% 92 0% 2 3 4 5

© CADFEM 2014

Ø To close the gap between tests and simulation 403 758 88% 399.5 0,8 % Ø To understand and find the unknown parameters 755 1295 71% 753.4 0,2 % Ø To replace Try-and-Error with process automation 1341 51%the key 874.8 1,5of % an unsuccessful Ø888To understand issues 1341 1755 31% 1305 improve 2,7 % design and subsequently the design 25

Rotordynamics • Dynamic response of an elastic rotor key task: avoid instable behavior in operation mode • Instable Behavior – Reasons most common: • internal rotor friction & internal (= rotating) damping mechanisms (!) • Bearing characteristics • Contact between rotor and stator • …

© CADFEM 2014

Rotordynamics in ANSYS: Campbell Diagram Frequency

© CADFEM 2014

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ANSYS Workbench: Siemens Rotordynamic Simulation • Generator test setup with superconductors 2.5D model of the rotor

• Rot

Modal analysis with 3D model

• Identification of critical speeds, resonance behavior and stability of the rotating machine • Consideration of gyroscopic effects • 2.5 axiharmonic elements combines computation speed and convenient modeling • Transfer of simulation know-how from CADFEM to Siemens by pilot project

© CADFEM 2014

By courtesy of Siemens AG

Campbell diagram: natural frequencies as function of the rotational speed

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Production History of Injection Molded Parts §

MoldSim container (Project Schematic) - Attach MoldSim container(s) to Setup cell(s) of e.g. Static Structural: Fiber orientation and initial stress data transfer to ANSYS Workbench Mechanical

© CADFEM 2014

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Adhesion Films • Modeled by contact/interface elements • Debonding occurs by adhesion film fracture • Debonding start and progression • Limitations: • One-time separation only • No further closing • No fatigue cycling

• Modeled by material • Detailed modeling: viscoelasticity, creep, fatigue… • Stress distribution inside adhesive layer availible • Stress strongly depends on accurate material model © CADFEM 2014

Quelle: Henkel

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Structural - Validation & Optimization • Expert level analysis • Virtual prototyping • • • •

Advanced material modelling Nonlinear statics & dynamics Robust Design Coupled physics

• Deployment of simulation methods • Reusable on designer level • Quality assurance

© CADFEM 2014

Structural - Connected Fatigue Life • Established solution from HBM • Certified by Germanischer Lloyd

• Multiaxial assessment • Material libraries • SN & EN libraries

• Load mapping • • • • •

Multi-channel time series Transient Vibration Temperature dependent Duty cycles

• Integration into Workbench

© CADFEM 2014

WB/FKM: Fatigue Assessment of non-welded solid parts • Fatigue Analysis using the local stress approach of FKM Guideline • Standard fatigue evaluation in the German machine building industry

• Fully integrated into ANSYS Workbench • Associative, parametric Workflow for sensitivity and optimization studies • Low effort by automatic determination of local stress gradients • Specific material data base included

*) 6th, revised edition, 2012, VDMA

© CADFEM 2014

WB/FKM-Weld: Fatigue Assessment of welded shell structures • Fatigue Analysis using the nominal stress approach of FKM Guideline • Standard fatigue evaluation in the German machine building industry

• Fully integrated into ANSYS Workbench • Reduced effort by automatic detection of weld connections • Specific material data base included

*) 6th, revised edition, 2012, VDMA

© CADFEM 2014

Agenda

Component & Assembly Design

System Simulations

Customized Solutions

Electromagnetic

Power train

Stretching the limits

Circuits

Automatization

Signal integrity

Behavioral models

Thermal Mechanical Fluids

© CADFEM 2014

System Simulation • Component interaction • Control logic & software • Electronics • Electro-mechanical components

System Component 1

…

Component N

• Multi-Level • Field 1 System • 0-D 1 2-D/3-D

Mechanical Thermal

Mechanical Interaction

Thermal

• Multi-Domain • Electro-thermal • Electro-mechanical • Electro-magnetic compatibility

© CADFEM 2014

Electric

Electric

Controls

Controls

Electric Powertrain System Interactions Controls Battery Inverter

Actuator

Energy Transfer Information © CADFEM 2014

Mechanics

Electric Powertrain - Thermal Simulation Heat-Sink + Fan à Model Extraction from CFD

Power Transistor à Electrothermal Characterisation © CADFEM 2014

Motor à Magnetic FEM Co-simulation

Heat-Sink + Fan - Model Extraction from CFD

1. Geometry & Boundary Conditions

2. 3-D CFD Model 3. Equation Model for “0-D” Simulation

© CADFEM 2014

Motor Magnetic FEM Co-Simulation Solved each time step

System simulation

Field simulation

• Source voltage • Control logic / software • Mechanics, Fluids, Thermal

• Induced voltage • Magnetic force / torque • Losses: Iron, copper, magnet

Solved each time step EQUL_I ERS

EQUL_D ERS

Inertia

LoadTorqueDamping

J

A B C

ROT1

N

ROT2 RMX

STF

LoadTorqueRamp

© CADFEM 2014

System Simulation - Control System - Simulink Co-Simulation Simulink: Control system

© CADFEM 2014

Simplorer Power electronics, actuator, Digital

System Simulation - Control System Embedded Systems Software Development C/C++ code

Compiler

Binary

Hardware Target Real-Time Simulator (HIL, SIL) © CADFEM 2014

System Simulation C interface Compiler

Code Generation

System model • Power Electronics • Actuator • Mechanical/Thermal • Parasitics/EMC • Digital Control (VHDL) • ...

EMC Issues for Power Electronics • Simulation of EMC for Power Electronics is a new discipline • Motivation • Closer proximity of power electronics to humans and sensitive electronics • Increased switching frequencies for loss optimization => More radiated energy • Tighter EMC regulations

© CADFEM 2014

Electro-Magnetic Compatibility • Electric-electric interaction of neighbouring devices • Coupling types: • Radiated: EM wave • Conductive: Capacitive, inductive, resistive

© CADFEM 2014

Electronic Design Issues

Display Panel

EMI/EMC

Power Integrity

Common mode radiation - Differential mode radiation -

Switching Noise (SSO/SSN) - Impedance Profile - Power/GND Plane Resonance - Return Path discontinuity -

Pwr Noise

Control IC

Driver IC

Memory

Signal

PCB

Signal Integrity Power Supplies

© CADFEM 2014

Impedance - Crosstalk - Reflection - Termination - Dielectric Losses -

Agenda

Component & Assembly Design

System Simulations

Customized Solutions

Electromagnetic

Power train

Stretching the limits

Circuits

Automatization

Signal integrity

Behavioral models

Thermal Mechanical Fluids

© CADFEM 2014

Electric Drives – Design Process

Stretching the Limits

Automatization

Behavioral Models

© CADFEM 2014

Example 1: Fast Battery Pack Simulation - BMWI Project

• „Zentrales Innovationsprogramm Mittelstand” (ZIM) • 2-year project à 350,000 € • Project partners • CADFEM • Zentrum für Sonnenenergie- und Wasserstoff-Forschung (ZSW) Baden-Württemberg • LionSmart

© CADFEM 2014

Example 1: Fast Battery Pack Simulation • Car battery pack with 3 layers of 33 cells à 99 cells pack • Each cell is a source of heat • Temperature of the center of each cell was chosen as output

Simulation Information § §

© CADFEM 2014

4000s, adaptive time step 33 min computing time

Example 2: Elastohydrodynamics (EHD) • Bartel, D., IMK, Uni Magdeburg:

Reibungsreduzierung von mischreibungsbeanspruchten Tribosystemen durch Simulation. 8. CADFEM CAE Forum, Stuttgart (2011). • Approximation of Navier Stokes Equation: Reynold’s Approach for Thin Fluid Films in Gaps à Tribo-X

roller on glass plate

fluid EHD result: pressure distribution

structural EHD result: shaft orbit © CADFEM 2014

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Electric Drives – Design Process

Stretching the Limits

Automatization

Behavioral Models

© CADFEM 2014

Automatizaton – Advanced Vibration Simulation of Electric Drives • Applicaton Examples • • • •

Claw pole machines Skewed teeth Axial flux machines … Source: CADFEM

• Individual force calculation mechanism

EMVIB

1_1_Teilmodell_Test1

6

• More complex load distribution • Periodic re-use of data for improved performance

5 4

Y1

3 2 1 0 -1 4.00

© CADFEM 2014

5.00

6.00

7.00 Time [ms]

8.00

9.00

10.00

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• Automated script collection • Has an extension character • Open source • Users encouraged to change and adapt

FluxLinage(d-axis) [Wb]

UDOs – User Defined Outputs

0.2 0 -0.2 -0.4 300

300 200 100

100 0 0 -100 -100 -200 -200 Iq [A] Id [A] -300 -300

• UDOs are scripts to define typical outputs from standard Maxwell data

400

Torque [N.m]

• Dq-Transform • Currents, fluxes, inductances • Matrix multiplication in background

200

200 0 -200 -400 300 200

200

100 0

0 -100 -200

Iq [A] © CADFEM 2014

-200 -300

Id [A] 53

Machine Design Toolkit • Toolkit • Has an extension character • Open source • Users encouraged to change and adapt

• Simulation for motor design • Automatic generation of models with different operation point • Torque Speed Curve Computation • Efficiency Map Computation

Existing Design

Create Reports

User Input Data

Simulate Txn Curve (parametric sweep)

Create designs

Solution Scheme

Current/Gamma Sweep

Retrieve Data from Sweep

• Supports all types of synchronous machines (also with Magnets)

© CADFEM 2014

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Electric Drives – Design Process

Stretching the Limits

Automatization

Behavioral Models

© CADFEM 2014

Function Models - Enabled by Automatization • Re-Use knowledge of 3-D Field Simulation for efficient analysis of full systems • Extract behavioral models from 3D field simulation • RLC Models for cables and connectors • Modal Reduction State Space Model for linear structural components by SPMWRITE • Linear Time Invariant (LTI) for cooling applictions with CHT • Krylov Model Order Reduction (MOR inside ANSYS) for cooling, thermoelectric & piezo applications • Equivalent Circuit Elements (ECE) for electromagnetic actuators • Universal nonlinear behavioral models by DoE • Efficent DoE scheme, automated model selection and verification © CADFEM 2014

Behavioral Models – Strategy for Industrie 4.0 • The system integration generates value • Customers require numerical description of product properties • 3D geometry is a standard • Physical properties are likely to follow

• Behavioral models of your components • Will give additional customer satisfaction • Increase your competition advantage • Seal and secure your IP

© CADFEM 2014

Agenda

Component & Assembly Design

System Simulations

Customized Solutions

Electromagnetic

Power train

Stretching the limits

Circuits

Automatization

Signal integrity

Behavioral models

Thermal Mechanical Fluids

© CADFEM 2014

ANSYS Workbench – Multiphysics Simulation Platform

© CADFEM 2014

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Parametric Simulation • What is the benefit of a single simulation? Material ± 5-10%

• Variation gives most understanding • • • • • • •

Geometric shape Material Current Windings Circuits Controller …

Boundary Conditions ± 1-20%

Geometry ± 0.1-10%

Result ± ??%

Manufacturing ± 5- 30%

Loads, Signals ± 0.1-50%

• DoE, Optimization, Robust Design

© CADFEM 2014

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Example • Synchronous machine with internal permanent magnets (IPM) • Defined Power • High efficiency • Low ripple • Cost minimization due to reduced material usage • Magnet • Steel

© CADFEM 2014

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Is a manual variation efficient? • Take 1 Parameter: Thickness of Magnet • The evaluation of the results is quite simple. • Just use two graphs in Excel.

mechanical Power (W)

Power 9350 9300 9250 9200 9150 9100 9050 9000 8950 8900 8850 4.9

5 5.1 5.2 5.3 Thickness of magnet (mm)

5.4

Mass Area of materia (mm²l

8.60E-05 8.50E-05 8.40E-05 8.30E-05 8.20E-05 8.10E-05 8.00E-05 7.90E-05 4.9 © CADFEM 2014

5 5.1 5.2 5.3 Thickness of magnet (mm)

5.4

Manual variations • Manual variation: normally 3 designs (low-mid-high) • • • •

Do you want to set this up manually? Can you ensure that all designs can be regenerated? Is this efficient? Ist the gathered information useful?

© CADFEM 2014

If 5 p.: 35 = 243 designs! If 7 p.: 37 = 2187 designs!

Benefit of stochastic sampling • Manual variation: normally 3 designs (low-mid-high) • Failed design: loss of large amount of information • Stochastic sampling: • No loss of information, best representation of variation space!

© CADFEM 2014

Technical Know How By Systematic Variation • Sensitivity = Understanding • What are the most important design variables? • Is there a correlation between parameters? • What is the range of results?

• Optimization • How to find the best result • Handle conflicting goals • Correlation of simulation and test

• Robust Design • Consider scatter in input

© CADFEM 2014

Sensitivity Study

B-Field

S1-Stress

© CADFEM 2014

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Sensitivity Study

© CADFEM 2014

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Sensitivity Study • Correlation Matrix • What is important? Positive correlation

• Where do we have correlations? • Design varialbe à result • Result à result No correlation

• Filter designs

Negative correlation © CADFEM 2014

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Optimization • Define multiple targets • Use advanced algorithms without beeing a mathematician • Find „the“ best design • Use the results of the sensitivity study • Fast – only seconds instead of hours • Accurate - verified prognosis quality

© CADFEM 2014

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Optimization • Define multiple targets • Use advanced algorithms without beeing a mathematician • Find „the“ best design • Use the results of the sensitivity study • Fast – only seconds instead of hours • Accurate - verified prognosis quality

• Re-do the optimization with different goals

© CADFEM 2014

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Robust Design • Consider scatter • Manufacturing tolerances • Material properties • Operation conditions

• Check the robustness • How safe is my design? • How many samples will fail?

© CADFEM 2014

Save

Failure

71

CADFEM – Simulation is more than Software PRODUCTS Software and IT Solutions SERVICES Advice, Support, Engineering KNOW-HOW Transfer of knowledge CADFEM in D, A, CH • 1985 founded • 2,300 customers • 12 locations • 185 employees (worldwide > 250) © CADFEM 2014

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