1 © 2014 The MathWorks, Inc.

Vom Konzept zum Modell physikalischer Systeme

Smarter Modellieren mit Simscape™

Maximilian Apfelbeck

MathWorks

München, 9.07.2014

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Key Take-Aways

Create accurate, reusable

plant models quickly and easily

Intuitive and easy to read multi-domain

modeling approach

Optimize system performance

– Develop in a single environment

V+

V-

u y s1 s2

s3

System

Actu

ato

rs

Sen

so

rs

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Model-Based Design Development Process

System-Level

Specification

Subsystem

Design

Subsystem

Integration & Test

System-Level

Integration & Test

Complete

Integration

& Test

Code Verification and

Validation

Integration testing

User Acceptance

Testing Requirements

Subsystem

Implementation

DSP FPGA ASIC

Embedded Software

Digital Electronics

C, C++ VHDL, Verilog

Implementation

Integration

MCU

Data Modeling

Algorithm

Development

Data Analysis

Research

System Design

Physical Components

Environment

Algorithms

Component Design

Design

with

Simulation

Executable

Specifications

Continuous

Test and

Verification

Automatic

Code Generation

Models

4

Model-Based Design Multi-Domain Modeling and Algorithm Development

System-Level

Specification

Subsystem

Design

Subsystem

Implementation

Subsystem

Integration & Test

System-Level

Integration & Test

Complete

Integration

& Test

Code Verification and

Validation

Integration testing

User Acceptance

Testing

DSP FPGA ASIC

Embedded Software

Digital Electronics

C, C++ VHDL, Verilog

Implementation

Integration

MCU

Requirements

System Design

Physical Components

Environment

Algorithms

Component Design

Data Modeling

Algorithm

Development

Data Analysis

Research

Methods for modeling systems in different domains

Physical Modeling (Schematic) Data Flow (Block diagram)

Event-Driven Systems Programing Language (Textual)

5

What Is This?

V+

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ω

dt

diLRiKV m

mmmbin

dt

dJDiKT mt

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How To Model This System?

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ω

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How To Model This System?

8

Fast and Efficient

Plant Modeling

Simulink is best known for

signal-based modeling

– Causal, or input/output

Simscape enables

bidirectional flow of power

between components

System level equations:

– Formulated automatically

– Solved simultaneously

– Cover multiple domains

Simulink: Input/Output

Simscape: Physical Networks

9

Through & Across Variables

p1 p2

q

Abstract to a physical network

All nodes have the same pressure (across variable)

Sum of flows (through variables) at a node is zero

Each component must specify an equation involving the through

and/or across variables at its boundary

p1 p2

p3

p4

10

Physical Systems in Simulink

Multibody mechanics (3-D) Mechanical systems (1-D)

Fluid power and control Multidomain physical systems

Electrical power systems

Electromechanical and

electronic systems

Sim

Me

ch

an

ics

Sim

Dri

ve

lin

e

Sim

Hyd

rau

lic

s

Sim

Ele

ctr

on

ics

Sim

Po

we

rSys

tem

s

Simscape

MATLAB, Simulink

Sim

Me

ch

an

ics

Sim

Dri

ve

lin

e

Sim

Hyd

rau

lic

s

Sim

Ele

ctr

on

ics

Sim

Po

we

rSys

tem

s

Simscape Mechanical Hydraulic Electrical

Thermal

Liquid

Custom Domains via

Simscape Language

Pneumatic Magnetic

N S

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Simscape Add-on Libraries

Multidomain

physical systems

Sim

Me

ch

an

ics

Sim

Dri

ve

lin

e

Sim

Hyd

rau

lic

s

Sim

Ele

ctr

on

ics

Sim

Po

we

rSys

tem

s

Simscape

MATLAB, Simulink

Simscape Mechanical Hydraulic Electrical

Thermal

Custom Domains via

Simscape Language

Pneumatic Magnetic

N S

SimDriveline™

– Gears, leadscrew, clutches, tires, engines

SimElectronics®

– Actuators, sensors, and semiconductors

SimHydraulics ®

– Pumps, actuators, pipelines, valves, tanks

SimMechanics™

– Multibody systems: joints, bodies, frames

SimPowerSystems™

– Three-phase electrical networks

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Physical Modeling Best Practice

Structure your system and componentize it

Get familiar with the available blocks

Build incrementally

Write test scripts/harnesses

Use appropriate level of fidelity

Add dampers, fluid volumes or capacities to un-stiffen the system

13

DC Motor Modeling Options V+

V-

Pre-build components

Equivalent circuit model with Simscape

components

Define a custom component using

Simscape language

14

Viewing Simscape Simulations Results ssc_explore

Explore simulation results

from entire physical network

– Select multiple signals

– Overlay or separate plots

– Arrange plots

– Extract plot to separate window

Spend more time analyzing,

less time simulating

Download from

MATLAB Central

http://www.mathworks.com/matlabcentral/fileexchange/28184-simscape-simulation-results-explorer

15

Developing Control Systems

Implement high-fidelity

nonlinear plant models

Extract linear model for use

with linear control theory

Explore interaction between

control system and plant

Optimize system performance

A x + B u = 0

Root Locus Bode Plot

Real Axis Frequency

y Plant

u Controller

s1 s2

s3

+

16

Key Take-Aways

Create accurate, reusable

plant models quickly and easily

Intuitive and easy to read multi-domain

modeling approach

Optimize system performance

– Develop in a single environment

V+

V-

u y s1 s2

s3

System

Actu

ato

rs

Sen

so

rs

17

Backup

Simscape Editing Modes

Share models with

other Simscape users

– Simulate, analyze, generate code

without purchasing extra licenses

Model Developer Purchases Simscape

and add-on products

Model Users Purchases Simscape

Add-on product installed,

No add-on purchases required

Function Full Mode

Restricted Mode

Add or delete regular Simulink blocks Yes Yes

Change Simulink solver, simulate Yes Yes

Change numerical parameters Yes Yes

Access PowerGUI functions, settings Yes Yes

Generate code Yes Yes

Add/delete blocks from add-on products Yes No

Make or break physical connections Yes No

Change block parameterization options Yes No

Change Simscape Local Solver Yes No

Model using Simscape

and add-on products

18

Backup

Simscape Equation Formulation and Simulation

Simscape performs

several steps before

starting a simulation

– Diagram parsing

– Symbolic simplification

– Index reduction

These steps are

performed automatically

to ensure robust

and quick simulations

Physical Network

(diagram)

Structural Model

Behavioral Model Reduced System

of Equations

Equations for

Simulation

Simulation

Results

Parse diagram

for component

connections

Incorporate component

equations, parameters,

and setup functions

Simplification of equations

through symbolic methods

Index

reduction

Integration