Active Resistance Emulation in Three-Phase Rectifier with Suboptimal Current Injection Milan Darijević1 , Predrag Pejović1 , Yasuyuki Nishida2 , and Johann Walter Kolar3 1 University

of Belgrade, Faculty of Electrical Engineering, Serbia [email protected], [email protected] 2 Chiba Insitute of Technology, Japan [email protected] 3 Swiss Federal Insitute of Technology, Zürich, Switzerland [email protected]

Introduction I

three-phase current injection based rectifier

I

suboptimal current injection

I

resistance emulator to improve efficiency

I

to use the dc-side filter or not? Predrag Pejović, Predrag Božović, Doron Shmilovitz, “Low Harmonic, Three-Phase Rectifier that Applies Current Injection and a Passive Resistance Emulator,” IEEE Power Electronics Letters, vol. 3, no. 3, pp. 96–100, September 2005

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optimization of RE to achieve minimal THD

I

the optimum somewhere close to the CCM-DCM boundary

I

models needed to optimize RE

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optimization

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experiments

Introduction, the rectifier vA

iA

iY /2

iER

C D1

D3

D5

LF

1

+ v1

i1

v2

i2

v3

i3

vAV

CPA IOUT

1 p(t) D2

iX

D4

iX

D6

iX

RE

CF

C iY /2 iB 1

1

CPB

vB

1 iY

1

1 vN

1

vOUT −

Introduction, now makes sense I

three-phase current injection based rectifier

I

suboptimal current injection

I

resistance emulator to improve efficiency

I

to use the dc-side filter or not? Predrag Pejović, Predrag Božović, Doron Shmilovitz, “Low Harmonic, Three-Phase Rectifier that Applies Current Injection and a Passive Resistance Emulator,” IEEE Power Electronics Letters, vol. 3, no. 3, pp. 96–100, September 2005

I

optimization of RE to achieve minimal THD

I

the optimum somewhere close to the CCM-DCM boundary

I

models needed to optimize RE

I

optimization

I

experiments

Models I I

goal: determine ik , k ∈ {1, 2, 3}

simplify the circuit as much as reasonably possible

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include the DCM!!!

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equivalent circuit methods Predrag Božović, Predrag Pejović, “Current Injection Based Low Harmonic Three Phase Diode Bridge Rectifier Operating in Discontinuous Conduction Mode,” IEE Proceedings Electric Power Applications, vol. 152, no. 2, pp. 199-208

I

let’s define: 1. vA0 = max (v1 , v2 , v3 ) 2. vB0 = min (v1 , v2 , v3 )

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diodes DA and DB to model the DCM

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out of four possible diode state combinations, three are of interest

Model of the rectifier with the filter DA

vA

iA

+

iIA

VC

C vA0

+ −

1

− +

vAV

−

1

+

vT R

vN = 0 iY

vT vB0

− +

+ −

VC

C

−

iIB DB

iB

vB

IER = vAV iY / (vA − vB ) , averaging present

IOUT − IER

Model of the rectifier without the filter iA

DA

vA iIA

+

C vA0

+ −

VC

1

− +

vAV

−

1

+

vT R

vN = 0 iY

vT vB0

− +

+ − C

VC −

iIB DB

iB

vB

iER = vAV iY / (vA − vB ) , no averaging

iER

IOUT

Solving the models

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determine iA and iB from the equivalent circuits

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determine i1 , i2 , and i3 from iA and iB

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convenient to normalize, v’s over Vm , i’s over IOU T

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the rest is mathematics . . .

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iterate over RE to optimize

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normalization, not exactly RE , but G , Vm /(IOU T RE )

Optimization 35

filter, filter, no filter, no filter,

30

CCM DCM CCM DCM

[%]

20

T HD

25

15 10 5 0

0

1

2

3

4 G

5

6

7

8

Optimization results

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with filter: 1. 2. 3. 4.

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without filter: 1. 2. 3. 4.

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GOP T = Vm /(IOU T RE OP T ) = 6.62 optimum in CCM T HDmin = 4.01% on RE there is 8.66% of PIN GOP T = Vm /(IOU T RE OP T ) = 6.50 optimum in DCM T HDmin = 4.22% on RE there is 8.40% of PIN

there is no need to use the filter!

Experiments

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goal: to verify models and the analysis

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up to 2 kW experimental setup

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input voltages 100 V rms

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output voltage about 230 V

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output current 5 A

Resistance emulator LEMI DER1

D

LB

iER

DER3

CPA

CB

CEMI S DER2

DER4

CPB CONTROL

n 1

iY +

vAV

−

Experimental results, with the filter 35

theoretical experimental

30

[%]

20

T HD

25

15 10 5 0

0

1

2

3

4 G

5

6

7

8

Experimental results, without the filter 35

theoretical experimental

30

[%]

20

T HD

25

15 10 5 0

0

1

2

3

4 G

5

6

7

8

Experimental results, joined 35

filter filter no filter no filter

30

[%]

20

T HD

25

15 10 5 0

0

1

2

3

4 G

5

6

7

8

Experiment, no filter, i1 and v1

Experiment, with filter, i1 and v1

Experiment, no filter, iY and vAV

Experiment, with filter, iY and vAV

Experiment, phase currents shapes

no filter

with filter

Conclusions

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three-phase rectifier with suboptimal current injection

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resistance emulator, output filter needed or not?

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models developed, DCM included

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optimization over RE to minimize T HD performed optimization results:

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1. with filter T HDmin = 4.01%, in CCM, 8.66% of PIN 2. without filter T HDmin = 4.22%, in DCM, 8.40% of PIN I

filter not needed!!!

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experimental verification

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excellent agreement with the model