mathworks technology session at ge closed-loop motor
TRANSCRIPT
1 ยฉ 2012 The MathWorks, Inc.
MathWorks Technology Session at GE
Closed-Loop Motor Control
Development
February 28, 2013
Brad Hieb
Tom Priestley
Marc Semma
2
Design Controller
Control System Toolbox
Robust Control Toolbox
Model Predictive Control Tbx
Optimize Control System
Simulink Control Design
Simulink Design Optimization
Model Physical Plant
System Identification Toolbox
Model-Based Calibration Tbx
Simscape
data model
3
Embedded System
Motor
Hardware
Controller
C Code
System Model
Model Based Design for Embedded Controls
Controller
C Code
Controller
Model
Motor
Model
Motor
Hardware
4
Embedded System
Motor
Hardware
Controller
C Code
System Model
System Modeling and Simulation
GE Tech
Session, Tues.
March 26
Controller
C Code
Controller
Model
Motor
Model
Motor
Hardware
5
Whatโs Next
Introduction and overview
PMSM motor characterization Characterization tests
Test data to model parameters
Validating the characterized model
Control system design Control model architecture
Tuning control parameters
Verifying closed-loop performance
Q&A
6 ยฉ 2012 The MathWorks, Inc.
Characterizing a Permanent Magnet
Synchronous Machine
Brad Hieb โ Application Engineer
7
Motivation
Why characterize the motor?
โ To develop a plant model
Why develop a plant model?
โ To simulate the system
Why simulate the system?
โ Simulation is a safe environment to try out new ideas without
the risk of damaging prototype hardware.
โ Visualization and analysis of the complex data in our system.
โ Gain confidence in our controller design before deploying on
hardware.
10
Key Point
Create accurate plant models by executing tests,
identify parameter values and verifying against real-
world data
Test Identify
Parameters Verify
12
Surface Mount PMSM Equations
Mechanical Model
Electrical Model
๐ฃ๐ = ๐ ๐๐ โ ๐ฟ๐๐๐๐ ๐๐ + ๐ฟ๐
๐
๐๐ก๐๐
๐ฃ๐ = ๐ ๐๐ + ๐๐๐ ๐ฟ๐ ๐๐ + ๐ + ๐ฟ๐
๐
๐๐ก๐๐
๐๐ = ๐๐๐
๐๐ = 1.5๐ ๐๐๐ + ๐ฟ๐ โ ๐ฟ๐ ๐๐ ๐๐
๐๐ = ๐พ๐ก๐๐ ๐๐ ๐ ๐ข๐๐๐ ๐๐๐ข๐๐ ๐๐๐ก๐๐, ๐ฟ๐ = ๐ฟ๐
๐
๐๐ก๐๐ =
1
๐ป ๐๐ โ ๐ ๐๐ ๐๐ ๐ฝ0 โ ๐๐๐ โ ๐๐๐๐๐
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Required Parameters
Electrical Model
Mechanical Model
๐ฃ๐ = ๐ ๐๐ โ ๐ฟ๐๐๐๐ ๐๐ + ๐ฟ๐
๐
๐๐ก๐๐
๐ฃ๐ = ๐ ๐๐ + ๐๐๐ ๐ฟ๐ ๐๐ + ๐ + ๐ฟ๐
๐
๐๐ก๐๐
๐๐ = ๐๐๐
๐๐ = 1.5๐ ๐๐๐ + ๐ฟ๐ โ ๐ฟ๐ ๐๐ ๐๐
๐๐ = ๐พ๐ก๐๐ ๐๐ ๐ ๐ข๐๐๐ ๐๐๐ข๐๐ ๐๐๐ก๐๐, ๐ฟ๐ = ๐ฟ๐
๐
๐๐ก๐๐ =
1
๐ป ๐๐ โ ๐ ๐๐ ๐๐ ๐ฝ0 โ ๐๐๐ โ ๐๐๐๐๐
15
Tests to Characterize Motor and Load
Motor Tests Parameters Identified Identification method
Back EMF Test
Number of Pole Pairs (p)
Flux Linkage Constant (ฮป)
Torque Constant (Kt)
Calculation
Friction Test
Viscous Damping Coefficient (b)
Coulomb Friction (J0)
Curve fitting
Coast Down Test
Rotor Inertia (H) Curve fitting
DC Voltage Step Test Resistance (R)
Inductance (L)
Parameter estimation
Load Tests Parameters Identified Identification method
Bifilar Pendulum Test Disc inertia (Hd) Calculation
16
Tests to Characterize Motor and Load
Motor Tests Parameters Identified Identification method
Back EMF Test
Number of Pole Pairs (p)
Flux Linkage Constant (ฮป)
Torque Constant (Kt)
Calculation
Friction Test
Viscous Damping Coefficient (b)
Coulomb Friction (J0)
Curve fitting
Coast Down Test
Rotor Inertia (H) Curve fitting
DC Voltage Step
Test
Resistance (R)
Inductance (L)
Parameter estimation
Load Tests Parameters Identified Identification method
Bifilar Pendulum
Test
Disc inertia (Hd) Calculation
17
Tests to Characterize Motor and Load
Motor Tests Parameters Identified Identification method
Back EMF Test
Number of Pole Pairs (p)
Flux Linkage Constant (ฮป)
Torque Constant (Kt)
Calculation
Friction Test
Viscous Damping Coefficient (b)
Coulomb Friction (J0)
Curve fitting
Coast Down Test
Rotor Inertia (H) Curve fitting
DC Voltage Step Test Resistance (R)
Inductance (L)
Parameter estimation
Load Tests Parameters Identified Identification method
Bifilar Pendulum Test Disc inertia (Hd) Calculation
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Coast Down Test
Coast down test used to identify:
Rotor inertia (H)
Test Extract
Parameters Verify
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Identify Rotor Inertia (H)
๐๐๐
๐๐ก=
1
๐ป๐๐๐ โ ๐๐๐ โ ๐ฝ0 โ ๐๐๐๐๐
๐๐๐๐๐ = 0
๐๐ = ๐๐0 + ๐ฝ0๐
๐โ๐๐ป๐ก โ
๐ฝ0๐
NRMSD = Normalized Root Mean Square Deviation
Note: J0 and b are known from friction
test. Curve fit equation for ฯr to find H.
Test Extract
Parameters Verify
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Validate Coast Down Test
NRMSD = Normalized Root Mean Square Deviation
Test Extract
Parameters Verify
21
Tests to Characterize Motor and Load
Motor Tests Parameters Identified Identification method
Back EMF Test
Number of Pole Pairs (p)
Flux Linkage Constant (ฮป)
Torque Constant (Kt)
Calculation
Friction Test
Viscous Damping Coefficient (b)
Coulomb Friction (J0)
Curve fitting
Coast Down Test
Rotor Inertia (H) Curve fitting
DC Voltage Step
Test
Resistance (R)
Inductance (L)
Parameter estimation
Load Tests Parameters Identified Identification method
Bifilar Pendulum Test Disc inertia (Hd) Calculation
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DC Voltage Step Test
Used to identify:
Phase resistance (R)
Phase inductance (L)
Test Extract
Parameters Verify
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Identify Phase Resistance (R)
๐ฃ๐ผ๐ ๐ก = ๐ ๐ฟ๐๐๐๐ก๐ ๐ก + ๐ ๐ ๐ก + ๐ฟ ๐๐
๐๐ก
๐ฃ๐ผ๐ ๐ก = ๐ ๐๐ ๐ก + ๐ฟ ๐๐
๐๐ก
๐ ๐ก = ๐๐ผ๐
๐ ๐ 1 โ ๐
โ๐ ๐๐ฟ
๐ก
๐ค๐๐๐๐: ๐ ๐ = ๐ ๐ฟ๐๐๐๐ก + ๐
๐ = lim๐กโโ
๐ฃ๐ผ๐ ๐ก
๐ ๐ก
๐ = ๐
2
๐ฟ = ๐ฟ
2
Test Extract
Parameters Verify
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Validate DC Voltage Step Test
NRMSD = Normalized Root Mean Square Deviation
Test Extract
Parameters Verify
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Tests to Characterize Motor and Load
Motor Tests Parameters Identified Identification method
Back EMF Test
Number of Pole Pairs (p)
Flux Linkage Constant (ฮป)
Torque Constant (Kt)
Calculation
Friction Test
Viscous Damping Coefficient (b)
Coulomb Friction (J0)
Curve fitting
Coast Down Test
Rotor Inertia (H) Curve fitting
DC Voltage Step Test Resistance (R)
Inductance (L)
Parameter estimation
Load Tests Parameters Identified Identification method
Bifilar Pendulum
Test
Disc inertia (Hd) Calculation
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Bifilar Pendulum Test
Bifilar pendulum test used to
identify:
Disc inertia (Hd)
Test Extract
Parameters Verify
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Identify Disc Inertia (Hd)
๐ป๐ = ๐๐๐ ๐2๐2
4๐2๐ฟ
๐ค๐๐๐๐: ๐๐ = ๐๐๐ ๐ ๐๐ ๐๐๐ ๐ ๐ = ๐๐๐๐๐๐๐๐๐ก๐๐๐ ๐๐ ๐๐๐๐ฃ๐๐ก๐ฆ ๐ = ๐๐๐๐๐๐ ๐๐ ๐๐๐ ๐ ๐๐๐ก๐๐ก๐๐๐
Measurements:
L = 2.356 (m)
b = 0.0565 (m)
md = 0.0425 (kg)
T = 2.21 (sec)
Test results
Hd = 6.993e-5 (kg-m2)
Test Extract
Parameters Verify
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Validate Bifilar Pendulum Test
Simulation result
T = 2.21 (sec)
Parameters:
L = 2.356 (m)
b = 0.0565 (m)
md = 0.0425 (kg)
Hd = 6.993e-5 (kg-m2)
Test result
T = 2.21 (sec)
Test Extract
Parameters Verify
31
Key Point
Create accurate plant models by executing tests,
identify parameter values and verifying against real-
world data
Test Identify
Parameters Verify
35
Where can I find more information?
Explore a demo on generating C code from a controller and verifying its compiled behavior and execution time
>> docsearch "Field-Oriented Control of Permanent Magnet
Synchronous Machine"
http://mathworks.com/products/demos/shipping/rtw/rtwdemo_pmsmfoc_script.html
Watch a recorded webinar: โEmbedded Code Generation for AC Motorsโ http://www.mathworks.com/company/events/webinars/wbnr61549.html
Watch 2012 MathWorks Automotive Conference recording of: โParameterizing and Verifying a Permanent Magnet Synchronous Motor Modelโ http://www.mathworks.com/company/events/conferences/automotive-conference-michigan/2012/proceedings/registration.html?video=3
Enroll in SAE Course: โModel Based Design: Delivering Quality Electronic Products Fasterโ http://www.sae.org/pdevent/C0806
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Tests to Characterize Motor and Load
Motor Tests Parameters Identified
Back EMF Test
Number of Poles (P)
Flux Linkage Constant (ฮ๐๐)
Torque Constant (Kt)
Friction Test
Viscous Damping Coefficient (b)
Coulomb Friction (J0)
Coast Down Test
Rotor Inertia (H)
DC Voltage Step Test Resistance (R)
Inductance (L)
Load Tests Parameters Identified
Bifilar Pendulum Test Disc inertia (Hd)
42
Tests to Characterize Motor and Load
Motor Tests Parameters Identified
Back EMF Test
Number of Poles (P)
Flux Linkage Constant (ฮ๐๐)
Torque Constant (Kt)
Friction Test
Viscous Damping Coefficient (b)
Coulomb Friction (J0)
Coast Down Test
Rotor Inertia (H)
DC Voltage Step Test Resistance (R)
Inductance (L)
Load Tests Parameters Identified
Bifilar Pendulum Test Disc inertia (Hd)
43
Tests to Characterize Motor and Load
Motor Tests Parameters Identified
Back EMF Test
Number of Poles (P)
Flux Linkage Constant (ฮ๐๐)
Torque Constant (Kt)
Friction Test
Viscous Damping Coefficient (b)
Coulomb Friction (J0)
Coast Down Test
Rotor Inertia (H)
DC Voltage Step Test Resistance (R)
Inductance (L)
Load Tests Parameters Identified
Bifilar Pendulum Test Disc inertia (Hd)