October 31/2003© Copyright by J. Bebic

2003

A Symmetrical HybridPower Flow Controller

Jovan Bebic, P.Eng.

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HPFC

Overview

VSC Basics Converter Based FACTS Devices Proposed Topology Steady-State Operation Reachable Sets and P- Curves Dynamic Control Summary Future Work

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HPFC

VSC Basics

Q

PP

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HPFC

Converter Based FACTS Compensators

SSSC

SV RV

0P SI RI

Q

1V 2VSX RX

STATCOM

SV RV

0P SI RIQ

SX RXMV

UPFC

SV RV

PSI RIEQ

SX RX1V

P BQ

2V

P

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HPFC

Proposed Topology

HPFC

SV RV

SI RI

SX RXMV

MQ

1V 2V

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HPFC HPFC

SV RV

SI RI

SX RXMV1V 2VXV YV

XP YP

MI

DCV

DCC

MB

X XmaxVV

S X maxII

Y Y maxVV

R Y maxII

1 1maxVV

2 2maxVV

M MmaxVV

X YP P

HPFC

SV RV

SI RI

SX RXMV1V 2VXV YV

XP YP

MI

DCV

DCC

MBSP 1P 2P RP

Limits and Constraints

X YP P 1 2P P S RP P

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HPFC

Equal Power Lines

S1I

S2I

SV

S S SP V I

SP constSI

RI

SV

RV

SP const

RP const

SV

RV

1V

2V

SI

RI

1 S S S

2 R R R

jX

jX

V V I

V V I

SV

RV

1V

2V

MI

SI

RI

MV

M S R

MM

MjB

I I I

IV

SV

RV

XV

YV

1V

2V

MI

SI

RI

MV

X 1 M

Y 2 M

V V V

V V V

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HPFC

Steady-State Operation

SV

RV

XV

YV

1V

2V

MI

SI

RI

MV

SV

RV

XV

YV

1V

2V

MI

SI

RI MV

SV

RV

XV

YV

1V

2V

MI

SI

RI

MV

SV

RV

YV

XV

2V

1V

MI

SI

RI

MV SV

RV

XV

YV

1V

2V

MISI

RI

MV

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HPFC

Reachable Sets

S R X max X max Y max Y max

Line Parameters Equipment Limits&

X ,X V , I ; V , I

S R

Line Conditions

, ,V V

S R,I I

1 1 2, ,P Q Q

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P- Curves

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System Properties

A system of variable structure, with infinitely many internal

operating points, for every line operating point.

A nonlinear control problem

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HPFC

Dynamic Control

table lookup1 1 2 Sref Rref, , ,P Q Q I I

X Y S Ruse , to control ,V V I I

Operator specifies1 1 2, ,P Q Q

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HPFC

HPFC

SV RV

SI RI

SX RXMV1V 2VXV YV

XP YP

MI

DCV

DCC

MBSP 1P 2P RP

Controlling the Power Balance of Converters

SV

RV

MI

SI

RI

MV

SI

DCvDCi

SedvSeqv

2 2x yxy

*DCv

*DCi

xy

xy

Srefi

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HPFC

Summary

HPFC UPFC

Power flow control Improves first swing stability margin

Topological symmetry Able to utilize existing shunt compensation

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HPFC

Future Work

Study machine based equivalents. Study dual topology. Formulate “optimality” algorithms

based on “reachable sets” algorithms.

Optimize the controller. Apply the concept of “equal power

lines” in load flow programs.