Workflows zur Systemanalyse und Optimierung in anhand der Auslegung eines Elektromotors

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Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang

M. Schimmelpfennig, Dynardo GmbH ACUM 2016 Linz

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© Dynardo GmbH

Dynardo

• Founded: 2001 • More than 60 employees, offices at Weimar and Vienna • Leading technology companies Daimler, Bosch, E.ON, Nokia, Siemens, BMW are supported

Software Development CAE-Consulting • Mechanical engineering • Civil engineering & Geomechanics Dynardo is engineering specialist for • Automotive industry CAE-based sensitivity analysis, • Consumer goods industry optimization, robustness evaluation • Power generation and robust design optimization

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 3 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Master of Design Robust Design Optimization (RDO) in virtual product development Our customized FE-consulting and software products enable you to: • Quantify risks • Identify optimization potentials • Perform variant studies • Secure resource efficiency • Ensure product quality • Improve product performance • Save time to market

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 4 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH optiSLang

• is an general purpose tool for variation analysis using CAE-based design sets (and/or data sets) for the purpose of

• sensitivity analysis • design/data exploration • calibration of virtual models to tests • optimization of product performance • quantification of product robustness and product reliability • Robust Design Optimization (RDO) and Design for Six Sigma (DFSS) serves arbitrary CAX tools with support of process integration, process automation and workflow generation

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 5 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Design Understanding Investigate parameter sensitivities, Design Improvement reduce complexity and Optimize design performance generate best possible meta models

CAE-Data

Robust Design

Measurement Data

Model Calibrations Design Quality Identify important model parameter Ensure design robustness for the best fit between simulation and reliability and measurement

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 6 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

SPDM

Input Workflow-Management Output 1 1 with Process Integration Input and for Output 2 Automatization 2

Input Output n m Excel Add-In ANSYS optiSLang other Solver

Postprocessing

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 7 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

optiSLang as an ANSYS Workbench plugin • optiSLang modules Sensitivity + MOP, Optimization and Robustness are directly available in ANSYS Workbench

Signal Processing module to work with curves inside ANSYS Workbench

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 8 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

CAX-Interfaces – the ANSYS Workbench Node • optiSLang Integrations provides the flexibility to extend the process chain • ANSYS Workbench can be coupled with different other solvers like MATLAB, SimulationX or • External geometry or mesh generators can work together with the ANSYS Workbench node

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 9 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 10 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

The motor simulation • ANSYS Maxwell 2D model • commutator principle

Sensitivity analysis with optiSLang • problem understanding • identification of influential parameters • identification of tradeoffs

Optimization with optiSLang • minimization of torque ripples

• maximization of the efficiency “eta”  η = Pout/Pin • suitable in this case: ARSM – adaptive response surface method

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 11 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

Commutator motor: working principle motor characteristics What creates the driving torque? • commutator principle • 12 lamellae & coils B-field from • one current branch magnets U0 = 12 V B-field from • fixed outer diameter coils OD = 78 mm

https://commons.wikimedia.org/w iki/File:Kommutator_animiert.gif

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 12 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor The model: 2D commutator motor FE-simulation

simulation details • time: 16.67 ms in 180 steps  Δt = 92.6 μs • time integration: Backward Euler • ensure that stationary state is reached (not all designs will become stationary at the same time)

data extraction: • key properties extracted by analyzing only the last cycle • access to output variables via Ansys Workbench  ParameterSet • access to signals via Ansys Workbench or ASCII files

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 13 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Model parametrization

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 14 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Model parametrisation magnet_coverage: magnet coverage in percent

magnet_thickness airgap gapwidth

magnet_rounding: as fraction of magnet thickness

rotor_borehole: diameter of motor axis

HS0

wall_thickness

magnet_voffset: for widening of air gap

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 15 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor Parametrization needs careful decisions example A: example B (used): • set rotor diameter • set motor size • set magnet thickness • set magnet thickness  motor size dependent  rotor size dependent

the bigger the better magnet takes away (in terms of torque & power) space available for rotor and vice versa

lost chance to learn real-world goal about a relevant conflict well tradeoff represented

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 16 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 17 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Calling Maxwell from optiSLang

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 18 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor Method A: using Ansys Workbench

in Maxwell • export scalar output variables to Optimetrics • parallel design computation with Optimetrics  Parametric

in the Workbench • optiSLang and Maxwell communicate through the ParameterSet

parallel/distributed computation: • RSM, PBS, LSF, HPC pack • use “optiSLang inside Ansys”

alternative: • optiSLang full version and a “Workbench node”

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 19 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor Method A: using Ansys Workbench

in Maxwell • export scalar output variables to Optimetrics • parallel design computation with Optimetrics  Parametric

in the Workbench • optiSLang and Maxwell communicate represented inside through the ParameterSet the Workbench node parallel/distributed computation: • RSM, PBS, LSF, HPC pack • use “optiSLang inside Ansys”

alternative: • optiSLang full version and a “Workbench node”

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 20 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor Method B: scripting and ASCII files direct coupling Maxwell and oSL

Maxwell • run batch job • run Python script text file for • write transient reports into files transporting input  signal data accessible parameters

optiSLang • text-based batch job node • extract signal data with ETK • signal data  free mathematical computations inside optiSLang

parallel/distributed computation: • optiSLang spawns Maxwell batch jobs

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 21 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor Method B: scripting and ASCII files direct coupling Maxwell and oSL

Maxwell • run batch job • run Python script the batch script • write transient reports into files  signal data accessible

optiSLang • text-based batch job node • extract signal data with ETK • signal data  free mathematical Python computations inside optiSLang

parallel/distributed computation: • optiSLang spawns Maxwell batch jobs

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 22 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor Method B: scripting and ASCII files direct coupling Maxwell and oSL

Maxwell • run batch job

• run Python script reading generated • write transient reports into files stored data  signal data accessible

optiSLang • text-based batch job node • extract signal data with ETK • signal data  free mathematical computations inside optiSLang

parallel/distributed computation: • optiSLang spawns Maxwell batch jobs

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 23 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor Method B: scripting and ASCII files direct coupling Maxwell and oSL

Maxwell • run batch job

• run Python script reading generated • write transient reports into files stored data  signal data accessible

optiSLang • text-based batch job node • extract signal data with ETK • signal data  free mathematical computations inside optiSLang

parallel/distributed computation: • optiSLang spawns Maxwell batch jobs

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 24 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor • extract signal data with ETK  green area for data analysis • FFT amplitudes of the reference signal  picture for postprocessing

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 25 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Sensitivity analysis

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 26 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Initial sensitivity analysis (100 DPs)

• Good Meta models for responses but bad for the torque ripples parallel coordinates plot: restrict some parameters by 20%-30% • select designs of interest = • restrict search space reduction of whole search space by 80%

airgap magnet edge radius magnet v. offset magnet coverage hs0 losses torque ripple magnet thickness gapwidth rotor borehole wall thickness mech. power amplitude

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 27 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

2nd sensitivity analysis (limited space – 200 DPs) • Very good metamodels for responses • Medium metamodels for the torque ripples • Analyze of the optimization potential • Multi-objective approach • Correlation analysis

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 28 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

2nd sensitivity analysis (narrowed space)

Correlations

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 29 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

2nd sensitivity analysis (narrowed space)

Correlations

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 30 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

2nd sensitivity analysis (narrowed space)

Correlations  no linear correlation for torque ripples Are there nonlinear dependencies?

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 31 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

2nd sensitivity analysis (narrowed space)

Getting more information with coloring

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 32 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

2nd sensitivity analysis (narrowed space)

designs with low torque ripples are scattered

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 33 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 34 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization problem definition

for eta torque

or eta P_mech

the tradeoff is already well captured in the random sampling

 optimization = picking

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 35 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization problem definition

for eta torque

or eta P_mech

the tradeoff is already well captured in the random sampling

 optimization = picking

but for torque_cv any other goal

the nonlinear interactions complicate the situation

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 36 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization: starting point

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 37 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

Objective function minimize:

(1-eta) + 0.4*torque_cv

Constraint:

torque ≥ 0.5

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 38 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

ARSM (adaptive response surface method) • objective function and constraint functions treated separately by ARSM • good convergence for the objective

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 39 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

Reference design

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 40 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

parallel coordinates plot • select designs of interest • restrict search space

Best design of the sensitivity

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 41 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

parallel coordinates plot • select designs of interest • restrict search space

Best design of optimization (ARSM)

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 42 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

reference design

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 43 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

sensitivity: best design

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 44 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Optimization of an electric motor

optimization: final design

Next steps: • Take final design as start for Maxwell 3D analysis • Ad some new parameters • Pre-analysis in 2D saves a lot of time because the design space in 3D is now smaller Last step: • Make a robustness analysis to check the influence of tolerances

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 45 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Summary

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 46 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

Summary - Optimization of an electric motor

Coupling Maxwell with optiSLang • via Workbench (node) easy use but only scalar parameters • via ASCII files powerful signal processing (incl. Large Scale-DSO) Sensitivity analysis • identification of important parameters and correlations • exploring tradeoffs and optimization potentials • meta models (MOPs): can be used for optimization visualization gain knowledge about nonlinear interactions

Optimization • ARSM: efficient & robust algorithm for optimization directly on simulation • torque ripples reduced by 73%, efficiency increased by 36% • play with parametrization and goals fast gain of engineering intuition

Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 47 M. Schimmelpfennig - Dynardo GmbH Linz 2016 © Dynardo GmbH

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Workflows for analysis and optimization of an electric motor with ANSYS and optiSLang 48 M. Schimmelpfennig - Dynardo GmbH Linz 2016