B E C K W I T H E L E C T R I C

Automatic Synchronizing of

Generators

Automatic Synchronizing of

Generators

Theory and ApplicationTheory and Application

B E C K W I T H E L E C T R I C

Synchronizing

An attempt to connect two alternating currents (ac) machines or systems with the following restrictions:

– Frequency difference (∆F)

– Voltage difference (∆V)

РPhase angle difference (Ư)

B E C K W I T H E L E C T R I C

Typical Sine Wave

B E C K W I T H E L E C T R I C

Line or Source Voltage

P = ES EQ---------------------------------------------------------------

XS XQsin Φ

VA

VBVC

B E C K W I T H E L E C T R I C

Phase at 0º

P = ES EQ---------------------------------------------------------------

XS XQsin 0º

VA

VBVC

VA

B E C K W I T H E L E C T R I C

Phase at 40º

P = ES EQ---------------------------------------------------------------

XS XQsin 40º

VA

VBVC

VA

B E C K W I T H E L E C T R I C

Phase at 80º

P = ES EQ---------------------------------------------------------------

XS XQsin 80º

VA

VBVC

VA

B E C K W I T H E L E C T R I C

Phase at 120º

P = ES EQ---------------------------------------------------------------

XS XQsin 120º

VA

VBVC VA

B E C K W I T H E L E C T R I C

Phase at 160º

P = ES EQ---------------------------------------------------------------

XS XQsin 160º

VA

VBVC

VA

B E C K W I T H E L E C T R I C

Phase at 200º

P = ES EQ---------------------------------------------------------------

XS XQsin 200º

VA

VBVC

VA

B E C K W I T H E L E C T R I C

Phase at 240º

P = ES EQ---------------------------------------------------------------

XS XQsin 240º

VA

VBVCVA

B E C K W I T H E L E C T R I C

Phase at 280º

P = ES EQ---------------------------------------------------------------

XS XQsin 280º

VA

VBVC

VA

B E C K W I T H E L E C T R I C

Phase at 320º

P = ES EQ---------------------------------------------------------------

XS XQsin 320º

VA

VBVC

VA

B E C K W I T H E L E C T R I C

Waveform Data

Synchronizing of 5-AT-Generator

B E C K W I T H E L E C T R I C

Waveform Data

Synchronizing of 6 Generator at Avon

B E C K W I T H E L E C T R I C

Typical Scheme

Synchronizing a Generator Breaker

25A = Auto Synchronizing Relay25SC = Sync-Check Relay52 = Generator BreakerCC = Close Coil

B E C K W I T H E L E C T R I C

Schematic of a Model System

Source: IEEE Technical Paper ABC-117-2

Torsional Mechanical System Generator

Excitation

Transmission Transformer

LargeSystem

LoadCoupling

QuillShaft

3,600 rpm5,100 rpm

IaIb

Ic

B E C K W I T H E L E C T R I C

Synchronizing Procedure

Steps:

1. Speed and voltage matching

2. Phase angle matching

3. Send close command

B E C K W I T H E L E C T R I CTypical Synchronizing

Scheme

Generator Synchronizing

CC

-DC

+DC

Sync. Selector

AutomaticSync.

Auto Synchronizer(M-0193)

Synchronism Check(M-0188)

52b

Breaker Close Coil

Manual Sync.

Control Switch

B E C K W I T H E L E C T R I C

Speed Matching

Results From Using ConventionalPulse Frequency Modulation Matching Method

B E C K W I T H E L E C T R I C

Speed Matching

Using Proportional Pulse-WidthModulation Method

TBP TBP TBP

B E C K W I T H E L E C T R I CTypical Synchronizing

Scheme

Operator-Assisted Automatic Synchronizing

CC

-DC

+DC

Sync Selector Switch

AutoSynchronizer

Synch-CheckRelay

52b

Breaker Close Coil

Breaker Control Switch(Operator)

Enable Sync(M-0193)

(M-0188)

B E C K W I T H E L E C T R I C

Automatic Synchronizing

• System Sync-Check Relaying• There is a “static” angle across the

circuit breaker• Used to close the circuit breaker on a

power system for:– automatic reclosing after a fault– supervises SCADA closing– supervise manual closing

52

25

Bus

Line

VT

+DC

-DC

CC

25

52

B E C K W I T H E L E C T R I C

Syncrocloser®

Interconnections

B E C K W I T H E L E C T R I CSynchronizing, Sync-Check

Relays and Generator Control Features

Model No.

Device No.

Automatic Synchronizer

Generator Control

Sync-Check Relay

Phase Angle Limit

Time Limit

Voltage Verification

Voltage Difference (∆V)

Frequency Difference (∆F)

Dead Line/Bus Closing

19” Rack Mount

S1/FT-21 Style Case

Vertical Mount

GES Retrofit

GTL Retrofit

M-0193

25A

√

—

—

—

—

—

√

√

—

√

—

*

*

—

M-0194

15/16

—

√

—

—

—

—

—

—

—

√

—

*

—

*

M-0188

25

—

—

√

√

√

*

*

—

*

√

—

*

—

—

M-0388

25

—

—

√

√

√

*

—

—

*

—

√

—

—

—

M-0245†

25

—

—

√

√

—

√

—

—

—

√

—

*

—

—

M-0359

25

—

—

√

—

—

√

√

√

—

√

—

*

—

—

M-0390

25

—

—

√

√

√

√

—

√

—

—

√

—

—

—

√ Standard * Optional — Not Available† High Speed Sync-Check relay verifies Phase Angle within one cycle

B E C K W I T H E L E C T R I C

THE END