G-Clare Matrix Converter

8/2/2019 G-Clare Matrix Converter

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Matrix Converter Technology and

Applications

Jon Clare, Pat Wheeler, Lee Empringham,

Liliana de Lillo

Presented by

Jon Clare

Professor of Power Electronics

Head of PEMC Research Group

[email protected] (+44 (0)115 9515546)


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Presentation Outline

Basic Matrix Converter Concepts

Some Practical Issues

Applications


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Matrix Converter Concept

Inputfilter

AC supply

Arbitraryfrequency

Bi-directional

switchLoad

Variable frequencyVariable voltage

output

SAaA

a

B

C

b c


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Some Basic Ideas

Each output phase can be connected to any input phase atany time

Switching pattern and commutation control must avoid lineto line short circuits at the input

Switching pattern and commutation control must avoid opencircuits at the output (assuming inductive load)

Switch duty cycles are modulated so that the averageoutput voltage follows the desired reference (for example a

sinusoidal reference) Average input current is sinusoidal when the input voltage,

output reference and output current are sinusoidal


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Example Switching Pattern

Tseq (sequence time)

SAb (on)

SBa

(on) SCa

(on)SAa

(on)

SBb (on) SCb (on)

SAc (on) SBc (on) SCc (on)

tAa tBa tCa

tAb tBb tCb

tAc tBc tCc

Outputphase a

Output

phase b

Outputphase c

Switching frequency = 1/Tseq

Simple illustration generally more sophisticated in practice

Modulation strategy ensures that tAa - tCc are generated so that theaverage output voltage during each sequence equals the target

output voltage. The sequence time is constant.

Repeats


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Illustrative Output WaveformsFin > Fout

Output line to supply neutral voltage

Time (ms)

Volts

-360

-240

-120

0

120

240

360

0 20 40

Time (ms)

Volts

Output line to line voltage

-600

-400

-200

0

200

400

600

0 20 40

50Hz in - 25Hz outswitching frequency500Hz

Lo w sw i t ch i n gf requency

sh o w n f o rv i sua l cla r i t y


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Illustrative Input Waveforms

Time(ms)-1.2

-0.8

-0.4

0

0.4

0.8

1.2

0 10 20 30 40

Time(ms)

Input current (unfiltered)50Hz in - 100Hz out

-1.2

-0.8

-0.4

0

0.4

0.8

1.2

0 5 10 15 20

Input current (unfiltered)50Hz in - 25Hz out

Lo w sw i t ch i n g

f requencysh o w n f o rv i sua l cla r i t y


8/35

Example Spectra

50Hz in - 25Hz out

2kHz switching

%

%

kHz

kHz

Output voltage

Input Current

25Hz

50Hz

Sidebands aroundmultiplesof the switching

frequency

Sidebands aroundmultiples

of the switchingfrequency

0

20

40

60

80

100

0 1 2 3 4 5

0

20

40

60

80

100

0 1 2 3 4 5

Exact nature of

spectra depends

on modulationmethod


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Modulation Control

A number of modulation strategies have been proposed.

All of them allow flexible control with the followingfeatures:

Continuous control of output voltage amplitude from zero up

to a maximum limit (typically 87% of input)

Continuous control of output frequency up to a maximumfeasible limit of approximately 1/10 of the switching

frequency

Control of input displacement factor: unity, leading and

lagging regardless of output power factor DC-AC and AC-DC conversion is an inherent feature by

setting either the input or output frequency to zero


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Matrix Converter Features

Direct conversion - No DC link - all silicon solution

No restriction on input and output frequency withinlimits imposed by switching frequency

Inherent bi-directional power flow (can be disabled)

Sinusoidal input and output currents

Potential for high power density if switchingfrequency is high enough

Output voltage limited to 87% of input voltage (formost modulation schemes)


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Switch Configurations

Back to Back Switch

Can Control Direction of Current Flow within each Switch

Useful (required) for most current commutation strategies

Common Emitter

Pair of switching devices arrangedwith emitters connected

Both devices can be gated from thesame isolated power supply

Common Collector

Pair of switching devicesarranged with collectorsconnected


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A Bi-directional Switchin a Single Package

Dynex 200Amp Bi-directional ModuleDIM200MBS12-A

CommonEmitter

Nine packages for a 3-phaseto 3-phase Matrix Converter

Used for larger converters,say >200Amps


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A Matrix Converter OutputLeg in a Single Package

Three packages for a 3-phaseto 3-phase Matrix Converter

Used for medium converters,say 50Amps to 600Amps

600V, 300A

(SEMELAB)

1700V, 600A

(DYNEX)


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A Complete Matrix Converterin a Single Package

One package for a 3-phaseto 3-phase Matrix Converter

Used for small converters,

say


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SA1

SA2

SB2

SB1

SA1

SA2

SB2

SB1

SA1

SA2

SB2

SB1

SA1

SA2

SB2

SB1

SA1

SA2

SB2

SB1

IL

Safe, Snubberless

Current CommutationExample of one method based on output current direction sensing

Current commutates from A to B with no short circuit of input or open circuit of output


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Matrix Converter Protection

To matrixconverteroutputs

Input toswitchmatrix

Voltage Clamp (typical approach)

Capacitor is small

depends on nature of load For the Matrix Converter based EHA (shown later)

machine inductance = 1.15mH

maximum output current is, say, 30Amps

capacitor required is 2 F2 F


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Input Filter Design

R

L

C

MatrixConverter

C chosen to limit voltage distortion at converter terminals

L chosen to limit current distortion at supply

R chosen to give adequate damping Limit overshoot on turn-on

Avoid excitation of resonance by supply or converter

Power quality specification has strong influence on filter size


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Smiths Aerospace EHA

A320 Aileron EHA

Full Stroke - 44mm

Max Force - 44500N

Typical rate 35mm/s

Frequency response 2Hz

Hydraulic RamHydraulic Ram

M

MatrixConverter

Accumulator

Bypass valve

M

MatrixConverter

Pump

Bypass valve


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EHA Control Loops

MatrixConverter

PMMotor Actuator

Control

Ram Position250Hz sampling rate2Hz bandwidth

Motor Current12.5kHz

sampling rate200HzBandwidth

Motor Speed

1.25kHz sampling rate20Hz bandwidth

Supply

LVDTResolverLEMs

Supply

Voltage

Ram Position Demand

Voltagetransducers Filter


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Prototype EHA Converter

Control Card withFPGA and A/Ds

Gate Drives

for IGBTs

Power Circuitand sensors

Air-cooledHeatsink

Cable toPM Motor

DSP Card


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Loading Rig


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Speed reve rsal a t 960 0r pm

Speed Control Results

-15000

-10000

-5000

0

5000

10000

15000

0.00 0.05 0.10 0.15 0.20 0.25 0.30

Speed[rpm]

-12

-10

-8

-6

-4

-2

0

2

4

0.00 0.05 0.10 0.15 0.20 0.25 0.30

Iqref[Amps]

-15

-10

-5

0

5

10

15

0.00 0.05 0.10 0.15 0.20 0.25 0.30

Io1[Amps]

-15

-10

-5

0

5

10

15

0.00 0.05 0.10 0.15 0.20 0.25 0.30

Io2[Am

ps]

-15

-10

-5

0

5

10

15

0.00 0.05 0.10 0.15 0.20 0.25 0.30

Time [secs]

Io3[Amps]

Motor shaft speed (rpm)

q-axis current (torque) demand

Phase A current

Phase B current

Phase C current


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Ram Position

(Unloaded)

Position Control Results

-20

-10

0

10

20

Position[mm]

Position Position ref.

-15000

-10000

-5000

0

5000

10000

15000

MotorSpeed[rpm]

Speed Speed ref .

-15

-10

-5

0

5

10

15

0 1 2 3 4 5 6 7 8 9 10

Time [secs]

Iq[Amps]

Iq

Motor Speed

q-axis currentdemand (torque)


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Motor speed

Ride-Through Operation

Torque Producing Current, Iq

Input supply voltages (400Hz)showing a 50msec period ofsupply interruption

7000

7500

8000

8500

0 .0 0 .1 0 .2 0 .3 0 .4 0 .5 0 .6 0 .7 0 .8

MotorSpe

ed[rpm]

-5

0

5

10

15

20

25

0 .0 0 .1 0 .2 0 .3 0 .4 0 .5 0 .6 0 .7 0 .8

Iq[Amps]

-200

-150

-100

-50

0

50

100

150

200

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

Time [secs]

InputSupply[Volts]


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EHA Converter driving IM Load

-8

-4

0

4

8

12

16

20

24

0.001 0.0015 0.002 0.0025 0.003 0.0035 0.004

-30

-25

-20

-15

-10

-5

0

5

10

A

A

M at r i x co n v er t e r d r i v i n g t w o 4 0 0 H z i n d u ct i o n m o t o r f a n s, V/ f m o d e

Outputcurrent(400Hz)

Inputcurrent(360Hz)


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Prototype Size Reduction

Examples of size reduction opportunities

Bespoke FPGA/DSP board

prototype uses evaluation DSP board

Heatsink and Input filter inductors

currently rated for continuous 150% overload in 70OCambient

optimised designs for realistic duty/environment needed

Input filter capacitors

selected on delivery time for prototype

different vendors parts < 50% volume

Voltage and current transducers

Easily obtainable parts selected for prototype

Much smaller replacements are available

Bespoke silicon/silicon packaging


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A 130kW Matrix Converter Vector ControlledInduction Motor Drive

PC Controller

Gate

Drivers

FiberOptic

Links

(27)

Current Direction Sensor

Desired

voltage, freq.

Serial

Link

Input

voltageD/A

PWM

FPGAMicroContr.

BidirectionalSwitches

Controller Board

(6)

(6)

(6)

Current

Direction

(3)

MotorSpeed

Encoder PC Controller

Gate

Drivers

FiberOptic

Links

(27)

Current Direction Sensor

Desired

voltage, freq.

Serial

Link

Input

voltageD/A

PWM

FPGAMicroContr.

BidirectionalSwitches

Controller Board

(6)

(6)

(6)

Current

Direction

(3)

MotorSpeed

Encoder

Work done in collaboration with the US Army

Research Labs

Design and construction of a large MatrixConverter power circuit

Results from 150kVA tests with anInduction Motor Load under v/f control

Closed loop vector control of a 150HPInduction Motor

Control Platform Infineon C167 control platform

FPGA based Current Commutationcontrol

Fibre-optic connections from control cardto to gate drives

Power Circuit Water cooled heat sinks

Laminated input power planes


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Resu l t s f r om a 600 Am p, 120 0VI GBT

Mat r i x Conver t e r

Test a t US Arm y ResearchLabora to r ies

150HP Induction Motor Load, 480Volt

supply

Output Power 129kW (156kVA)

Switching Frequency: 4kHz

(Limited by processor)

Output Currents

Output Voltages

-1750

-1500

-1250

-1000

-750

-500

-250

0

250

500

750

1000

1250

1500

1750

0 5 10 15 20 25 30 35 40 45 50

Time, milliseconds

Volts

- 5 0 0

- 4 0 0

- 3 0 0

- 2 0 0

- 1 0 0

0

1 0 0

2 0 0

3 0 0

4 0 0

5 0 0

0 5 10 1 5 2 0 25 3 0 3 5 4 0 45 5 0

Amps


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vc

va

vbv

vvd

*

vq*

Rotor Speed

Flux Current DemandCompensation terms

iq*

sl e

r

id

iq

i

i ic

ia

ib

SpeedControl

Id CurrentControl

ej

e-j

Timers

3/2

2/3

Iq CurrentControl

*

*

d

q

i

i

dt

r

ref id*

Speed Demand

inputvoltages

MatrixConverter

ControlAlgorithm

PWM

MICRO-CONTROLLERInfineon SAB80C167

motor

3-Phase Supply

InputFilter

MatrixConverter

Power Circuit

FPGA

CurrentA to D

GateDrives

Voltage

A to D

FPGA

Encode

A B

A B

Up/Down

vAB

vBC

Closed Loop Vector Scheme applied to theMatrix Converter Induction Motor Drive

0

200

400

600

800

1000

Speed[rpm]

-400

-200

0

200

400

600

800

Id,

Iq[Amps]

-600

-400

-200

0

200

400

600

0 1 2 3 4 5Time [secs]

OutputCurrents[Amps]

0

200

400

600

800

1000

Speed[rpm]

-400

-200

0

200

400

600

800

Id,

Iq[Amps]

-600

-400

-200

0

200

400

600

0 1 2 3 4 5Time [secs]

OutputCurrents[Amps]

Closed Loop Vector Control of a150HP Induction Machine

Control Platform (old!)

Closed Loop Motor Control

Fi ld P S l U i F O L


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Field Power Supply Using a Four-Output LegMatrix Converter

collaborative proj ect wit h t he US Arm y Research Labs

LoadMatrix10kWGenDIESEL

ENGINE

FILTER

Engine

Speed Control

Modulation

D,Q, Control

and Engine Demand

MATRIX

CONVERTER

FILTER

Space

Vector

ModulatorInput Voltage

Output Voltage

Output Current

-250

-200

-150

-100

-50

0

50

100

150

200

250

0.000 0.001 0.002 0.003 0.004 0.005 0.006 0.007 0.008

Time [s]

OutputLinetoLineVo

ltages[V]

Field power supply

Matrix Converter Power Circuit

Variable Speed Diesel Engine Permanent Magnet Generator

Designed for 10kVA Load

50Hz, 60Hz or 400Hz Output Frequency

IGBT based Matrix Converter

25kHz Sampling Frequency DSP/FPGA Control Platform

LC Output Filter

Output Voltage Control Loop designedusing a Genetic Algorithm Optimisation

400Hz Output Voltage Waveforms


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MotorMotor

Electronics

MotorMotor

Electronics

Integrated EMATechnology demonstrator

To design and build an Integrated Electro Mechanical Actuator (EMA) intendedas a technology demonstrator for a rudder actuator on a large, twin-engined,civil aircraft.

Need to continuously deploy rudder under some flight conditions drives thermal

design (stationary motor with high torque) Natural cooling considered


32/35


Gate Drive Circuits

Ballscrew housing

Input Filter Capacitors

Switching Signals

Voltage Clamp DiodesVoltage Clamp Capacitors

30kW matrixconverter integratedwith ballscrew-heatsink

d


33/35


Bespoke PM motor designed

and constructed Speed limited to 4950rpm by

use of existing actuator fordemonstrator

I d EMA


34/35


Initial dynamic tests on unloaded motor (speed reversal)

Motor current (A) vs time Motor speed vs time


35/35

Conclusions

Matrix converters are a reality

Matrix converters can be constructed at 100kW+

Matrix converters are interesting for aerospace applications

Potential for high power density

Power quality

New devices and device technology (Silicon Carbide, reverseblocking IGBTs?) will increase attractiveness

Research now needs to be applications focussed

Continue better understanding of application issues

Optimised design

Realise potential

Other direct converter structures also interesting

eg Sparse 2-stage direct converter

Documents

G-Clare Matrix Converter