Dr.-Ing. Norbert Fröhleke

PIBRAC - Piezoelectrical Brake Actuator

Power Electronics and Electrical Drives 2Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

PIBRAC – Piezoelectric Brake ActatorMotivation for actuator enabling direct drive brakingFunctional principle of multi-mass ultrasonicPower supply and control development

Dr.-Ing. Norbert Fröhleke,Department of Power Electronics and Electrical Drives,University Paderborn, Germany

EU-Projekt PIBRACPIezoelectric BRake ACtuator

Power Electronics and Electrical Drives 3Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

PIBRAC Consortium

Projektleitung, Motorentwicklung Teilprojektleitung,

Spezifikation, Tests

Teilprojektleitung,Brems-systeme, Spezifikation, Tests Teilprojektleitung,

Reibschichtentwicklung

Entwicklung Leistungselektronik, Modellierung und Regelung

FEA-Modellierung für Validierung und Design

Materialtests,Ermüdungsuntersuchungen

Materialtests, Simulation,Prototypintegration

Produktion mechanischerTeile, Prototypenbau

Herstellen Piezokeramiken

Beschichten der Reibschicht

Power Electronics and Electrical Drives 4Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

Current Aircraft Brake Actuator

Power Electronics and Electrical Drives 5Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

1. Electric motor2. Transmission3. Bullet thread4. Rotor disc from carbon5. Stator disc from carbon

Advantages by „full electrical” aircraft:

• Reduction in volume and weight• Increase in reliability and operating

safety • Reduction costs for operation and

maintenance

Electromagnetic Brake

Power Electronics and Electrical Drives 6Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

1

10

100

1000

0,1 1 10 100 1000 10000

MAGNETIC

PIEZOELECTRIC

HYDRAULIC

canon

Sagem

DaimlerChrysler

Sagem

kurosawa

shinseiSagem

crouzet

W

W/kg

Power Density vs. Power

Power Electronics and Electrical Drives 7Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

Hydraulic Electromagnetic

Masse

Inertia

Maintenance

Environment & Fire risk

Peak power demand

Piezoelectric(Expected)

Technology Comparison

Power Electronics and Electrical Drives 8Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

Inverterandfilter

Power supplycontrol

motorcontrol

actuatorcontrol

brakemanagement

MM-USM

actuatorSAG

MB

actuator and motor control power electronics

DR29879D.220.2c

Objectives:Development of power supply and control architecture for Piezo Brake Actuator with a multi mass ultrasonic motor (MM-USM)

Power Supply Scheme and Control

Power Electronics and Electrical Drives 9Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

converter filter motor

Rm

CmLm

CpRpLp

LSCS

converter filter motor

Rm

CmLm

CpRpLp

LSCS

Tangential Mode

Normal Mode

Operating Principle of MM-USM

Power Electronics and Electrical Drives 10Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

normalelements

tangentialelements

rotordiscs

elastic layer

rigid layer

blockmass

Operating Mode of MM-USM

Power Electronics and Electrical Drives 11Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

T v

tangentialmode

normalmode

powersupply

uT

uN

pow

er s

uppl

y co

ntro

l

optimal point

control

xN

xN

frequencypart

amplitudepart si

gnal

ge

nera

tion

torque (force)control

T

speedcontrol

speed,position

v or ω

T*

positioncontrol

l or θ

Δl or ΔΘ

v* or ω*

operational profile controland

global control management

relevant sensor and internal signals

(TBD)

posi

tion

spee

dlim

itatio

n

torq

uelim

itatio

n

brakeforcesignal

addi

tiona

lsi

gnal

s

feed

back

sign

als

xt

90° phasecontrol KNfN

xt

uN

uT

|uN*|

φ(uT*)

operating

point

Δlor

ΔΘ

torq

ue

Δ

Δl or ΔΘ torqueestimation

forc

e

φ(uT*)

freq

|uT*|

torque

forc

e

Proposed Control Strategy for PIBRAC Motor

Power Electronics and Electrical Drives 12Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

DSP FPGA

CO

NVE

RTE

R

Com

mun

icat

ion

Com

mun

icat

ion MM-USM

PWM

Voltageand

currentcontrol

Monitoring

Operational profilecontrol management

brakeforcesignal

feedbacksignals

position, speed, forcecontrol

amplitude, frequency,phase control

online identification

PIBRAC Control Realisation

Power Electronics and Electrical Drives 13Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

PIBRAC Motor Construction

Power Electronics and Electrical Drives 14Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

Actuator Design

Motor (including isthousing)

800g

Roller screw 372g

Thrust bearing 37g

Clutch 279g

TOTAL 2027g

Needle bearings (x2) 139g

Actuator Housing 400g

Max. diameter 113mm

Motor min. diameter 74mmLength 123mm

Power Electronics and Electrical Drives 15Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

Actuator Kinematic

Rotor

Power Electronics and Electrical Drives 16Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

EMA PIBRAC

Component Weight Quality Total weight Weight

Actuator 4kg 16 64Kg 2,1kg 16 33,6kg

Cable 100kg 1 100kg 126kg 1 126kg

10,5kg

Quality Total weight

42kgController 10,5kg 4

206kg

4 42kg

Total 202kg

EMA

31%

49%

20%

Actuator Cable Controller

PIBRAC

17%

62%

21%

Actuator Cable Controller

Weight Comparison

Power Electronics and Electrical Drives 17Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45-170

-160

-150

-140

-130

Motor Voltage Transfer Function Gvx(jω)

Mag

nitu

de |G

(j ω)|

[dB

]

30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45-180

-135

-90

-45

0

Frequency [kHz]

Pha

se [ °]

fa = 160 N*s/m

fa = 640 N*s/m

fa = 1280 N*s/m

fa = 2976 N*s/m

30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45

-130

-120

-110

-100

Motor Current Transfer Function Gix(jω)

Mag

nitu

de |G

(j ω)|

[dB

]

30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45-270

-225

-180

-135

-90

Frequency [kHz]

Pha

se [ °]

fa = 160 N*s/m

fa = 640 N*s/m

fa = 1280 N*s/m

fa = 2976 N*s/m

fmech mechanical resonance

fmech mechanical resonance

Motor Impedance Z(jω)

30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45

0

10

20

30

40

50

60

Mag

nitu

de|Z

(jω)|

[dB

]

30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45-90

-45

0

45

Frequency [kHz]

Pha

se [ °

]

fa = 160 N*s/m

fa = 640 N*s/mfa = 1280 N*s/m

fa = 2976 N*s/m

M = 2.41

M = 5.61M = 11.2M = 44.9

fa = 640 N*s/mφ = - 5.1° P = 0.56kWS = 0.56kVA Q = - 50VAr

fa = 1.28 kN*s/mφ = - 10.1° P = 1.12 kWS = 1.14kVA Q = - 199VAr

fa=2.976 kN*s/mφ=- 22.5° P = 2.6 kWS=2.81kVA Q=- 1.08kVAr

fa = 160 N*s/m φ = 0°S = P = 140 W

Load Variation for MM-USM

Power Electronics and Electrical Drives 18Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

fct

ft2xt2

fN2

Normal Force

kct

~fc2

fN2

fct

ft1xt1

fN1

kct

~fc1

Elasticlayers

Substrate

mBlock

mBlock

Rotor

x > 0

Frictioncoefficient

μmi mimd md

fN1

kt

Mechanical Modelling

Disc contact area Generalized motor model

disc

rigid layer

block

mass

elastic

layer

disc

m i

m

k t

k ct

x tx i

x

y

fct

v d

fem

fem

f f

fc

it

ut

fc xt xt

xi xi

uticp

fN

v

vd

ff

Cp 1/Rp Nt

Nt

m

mi

fct

kct

ktelastic layer

block mass

dv

fem

fem

ff

ipz

electrical part

xtipz

friction

Motor Modelling

Power Electronics and Electrical Drives 19Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

-2-1.5

-1-0.5

00.51

Fig. 1 MM-USM friction modes

0 0.25 T 0.5 T 0.75 T 1.00 T 1.25 T -300

-200

-100

0

100

200

300

stickingsliding

braking driving

0 0.25 T 0.5 T 0.75 T 1.00 T 1.25 T

-μfN

fem

ff

μfN Forces

Speed vi

vd

it

ut

fc xt xt

xi xi

uticp

fN

v

vd

ff

Cp 1/Rp Nt

Nt

m

mi

fct

kct

kt

discrigid layer

blockmass

elasticlayer

elastic layer

block mass

dv

discmi

m

kt

kct

xtxi

x

y

fct

fem

fem

ff

vd

fem

fem

ff

fc

ipz

electrical part

xtipz

friction

Simulation Results

Power Electronics and Electrical Drives 20Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

-50 -40 -30 -20 -10 0 10 20 30 40 50

-40

-20

0

20

40

60

80

Ut = 0 VUt = 40 VUt = 80 VUt = 120 VUt = 160 VUt = 200 VUt = 240 VUt = 280 V

Mot

or to

rque

T[N

m]

Disc speed Ωd [rad/s]

Motor Torque vs. Disc Speed

Power Electronics and Electrical Drives 21Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

Power Electronics and Control

Power Electronics and Electrical Drives 22Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

S1

S2

S3

S4

S5

S6

Lp Cp

Ls Cs

Vi/2

Vi/2

Design Specification:

a) Input voltage 270 V DC

b) Maximal output voltage 270 V AC (peak)

c) Frequency 30 - 40 kHz

d) Maximal electrical power 1500W

Power Supply Structure

Power Electronics and Electrical Drives 23Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

Lp Integrated in Actuator

Parameters of Lp per 1 actuator172 uHDim.: 42*21*15 mm3

weight: 250 gLosses: 3 W

LLCC-filter Filter Components

Cable and Filter Components

Weight: 10.5 kgSum

Weight : 5 kgFilter

Weight: 1.5 kgCase

Weight : 4 kg

Efficiency: 97.5%

So = 9.4 kVAPo = 9 kW

Inverter

ParametersComponents of power supply

Power Electronics and Electrical Drives 24Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

Power Balance of Power Supply

Power supply output power at full load

1500W

Losses

Inverter losses 47W

Filter losses 11W

Total power supply losses 93W

Efficiency 93,8%

Cable losses 15W

Additional losses 20W

50%

12%

16%

22%

inverter losses filter losses cable losses additional losses

Power Electronics and Electrical Drives 25Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

MM-USM Power Balance

MM-USM output power 550W

Losses

Dielectric losses 5W

Deformation losses 347W

Total power supply losses 860W

Required electrical power 1410W

Efficiency 39,0%

Vibration losses 508W

39%

0%25%

36%

MM-USM output power dielectric lossesdeformation losses vibration losses

Power Electronics and Electrical Drives 26Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

M

A

D

DA

UD

PWM

Voltagecontrol

Sensor

SignalProcessing

DA

ifilter

u*cp

ucp

iiP

i*p

ifilter

Sa

Sb

xpi

iLp

i*filter

F*pϕΔ

currentcontrol

u*filter

Filter

ucp

sincos

sincos

i*Cp ufilterΔ

Dem

odul

atio

n

Dem

odul

atio

n

2

2

2

2

2

2 2

)sin(ˆ)(, tutu refsref ω=)cos(ˆ)(, tutu refcref ω=

*,scpu

*,ccpu ccpu ,

scpu ,

)(tucp X

X

Cascade Voltage and Current Control Scheme

Demodulation

Voltage and Current Loop Control Scheme

Power Electronics and Electrical Drives 27Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

Power inverter

Equivalent load

FPGA Controller Board

Transf., Ls, Cs

Lp, Cp

Prototype Hardware Configuration

Power Electronics and Electrical Drives 28Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

EMA PIBRACSteady-State Section

Converter efficiency 0 0

Motor efficiency + -

Mechanical efficiency 0 0

Dynamic Section

Inertia - +

Ways of improvement section

No lubricant - +

Conclusion

??? ???

Conclusion

Power Electronics and Electrical Drives 29Prof. Dr.-Ing. Joachim Böcker, Dr.-Ing. Norbert Fröhleke

Thank you for your attention !