introduction of synchronous generators technology syn hydro technical introduction_1.pdf · rotor:...

TECO-Westinghouse Motor Company 5100 N. IH-35, Round Rock, TX 78681

Toll-Free: 1-800-451-8798 Phone: 512-244-4141 Fax: 512-244-5512 www.tecowestinghouse.com

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Introduction of Synchronous Generators Technology



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Capability KW and Speed Ranges:

Slow Speed Machines: 150 to 450 rpm 1,000 to 20,000 + KW

Medium Speed Machines: 514 to 900 rpm 1,500 to 75,000 + KW

High Speed Machines: 1000 to 1200 rpm 3,000 to 27,000 KW

High Speed Machines: 1500 to 1800 rpm 2,000 to 15,000 KW

Basic Specifications: 1. Voltage: 2300 to 13,800 volts

2. Frequency: 50, 60 Hz

3. Enclosures: ODP, WPI, WP2, TEWAC and TEAAC (IP00, IP22/24, IP54)

4. Power Factor: 1.00 (unity), 0.90, 0.80 or as specified leading

5. Type: Vertical or Horizontal

6. Bearings: Sleeve or Kingsbury-Type Thrust Bearings

7. Exciter: Brush or Brushless Excitation

8. Frame construction: Engine, Pedestal or Bracket Frame Construction



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Rotor:

• TWMC Synchronous Machine rotor assemblies are designed and built with proven construction

methods to insure long life and dependable service.

• Synchronous rotor construction starts with a high strength forged steel shaft that is adequately

sized for the electrical and mechanical loads that the motor must withstand in rolling mill service.

The shaft is machined to a smooth finish with generous radii to assure minimum stress

concentrations.



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Left- Fabricated spider with bolt on poles. Right- Solid dovetail shaft/spider forging

• Both types of shaft and spider assemblies seen above are designed to withstand the harsh impact

loads seen in applications. They are final machined to accept the pole assemblies and then

balanced at several points during the manufacturing process.

• Dovetail poles are made from accurately stamped steel laminations which are stacked, pressed and

bolted. Each pole has two individual dovetails which assure tightness of the pole to spider under

the most severe conditions. Each pole assembly is easily removable.

• Bolted on poles are made from accurately stamped steel laminations which are stacked, pressed

and bolted. Each pole is built around a special steel core beam. This machined bar is tapped to

accept high strength studs and provides a rigid member to assure tightness of the pole to spider

under the most severe conditions. Each pole assembly is easily removable.

• All pole assemblies have integral upper coil supports to protect the coil ends from centrifugal

forces, thus preventing any movement or deflection from occurring during overloads.



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• The field winding is constructed from layers of rectangular copper strap that are edge bent into a

coil configuration. Insulation is placed between each layer, after which the winding is pressed and

baked assuring a very rigid structure. The finished coils are then fitted to the pole assembly, over

ground wall insulation and between large glass laminate top and bottom washers.

• The damper bars (which are oversized electrically) are tightly fitted in the pole shoe. Swaging is

often done to assure a tight fit. The damper connections at the ends of the bars are brazed to the

bars and do not restrict thermal growth of the bars. There are also sleeves brazed to the bars on

each end to prevent bar thermal migration. The end result is a damper system which can

mechanically withstand all of the forces imposed on it during service without fatigue problems.

• The new synchronous rotor assembly can be supplied with either a machined shaft extension for a

removable half-coupling, or an integral machined shaft flange drilled to mate with the customers

driven equipment as seen above.

• TWMC utilizes a keyless “shrink fit” to eliminate slippage under heavy torque conditions and the

stress concentrations produced by keyways. Our keyless couplings are shrunk onto the shaft with a

high interference fit that provides a strong bond. Special fittings and groves allow the coupling to

be removed and even installed using hydraulic pressure.

• Key-type couplings can be designed when specific application or requirements exist.



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Frame & Stator:

• All Synchronous stators have a rugged fabricated steel frame structure capable of being lifted as a

unit. The massive frame feet are integral with the frame, accurately machined, with adequate hold

down capabilities and pre-drilled with starter dowel holes.



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• Stator cores are made from high grade, low loss Silicon steel, accurately stacked on high strength

steel studs between massive endplates. After the core is pressed, the studs are accurately torqued.

Additional steel beam bracing is welded between endplates forming a rigid assembly.

• The winding end turns are rigidly supported at multiple locations on both DE and NDE. Solid steel rings

are supported by steel brackets welded to the frame. This very sturdy design assures resistance to the forces

imposed on the windings in severe service applications.



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Insulation & VPI:

• TWMC stator coils feature our exclusive mica based "Thermalastic" insulation system. Introduced

first by Westinghouse, Thermalastic systems are the standard by which all systems are measured.

Often copied yet are never duplicated. TWMC employs two distinctive types of Thermalistic

stator coil insulation systems. Each being stable and under the most severe environments and

applications.

• For Synchronous machines having very large diameters, Thermalastic insulation is applied to

individual coils. In this “Hard Coil” system each coil is impregnated with TWMC’s proprietary

low viscosity, solventless resin, then pressed and cured before being wound into the stator core

slots. After winding, the coils are fully wedged, connected, and the bracing system is installed.

The completed “Hard Coil” stator assembly is then coated with a highly durable epoxy varnish to

provide a tough, smooth, dirt resistant finish. This design offers a very rigid system, having

excellent heat transfer capabilities and is able to withstand the rigors of variable speed reversing

steel mill service.



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• For the smaller Synchronous stators, TWMC utilizes a “VPI” Vacuum Pressure Insulation – Post Impregnation Thermalastic Epoxy insulation system. In this system stator coils are wound, wedged,

connected and the bracing system is installed into the stator core. The wound stator core is first pre-

heated the placed into the VPI tank. Here the stator undergoes vacuum cycles followed by high

positive pressure to force epoxy resin into all components of the wound stator. After the complete VPI

cycle, the stator is baked afterwards to fully cure the resin. The entire VPI cycle is then repeated. After

the final treatment, the insulated stator is coated with a highly durable epoxy varnish to provide a

tough smooth, dirt resistant surface.

Exciter: Brush & Brushless

• Heavy duty collector ring assemblies are made from a special material for low friction and good

brush riding ability. They are shrunk onto the shaft and insulated from it. Located inboard of the

bearing they have their own housing and ventilation. The carbon dust from the brushes will not

enter the main motor air stream. The brushes are readily accessible for servicing and inspections.

• Westinghouse pioneered the Brushless Exciter. Provides DC Current to the Motor field windings.

• Brushless Exciter Stator is supported by a fabricated steel perch with a rigid designed to reduce

vibration.



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Bearings: TWMC uses only the highest quality insulated, split sleeve babbited type bearings. Both bracket and

pedestal designs are fitted with oil rings and are self contained. RTD's are mounted in each bearing liner.

The drive end bearing controls generator endplay and has a thrust surface for any turbine generated thrust.

The bearing assemblies are bolted to heavy steel fabricated & machined bedplates.



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Enclosures & Ventilation:

The ventilation system is self contained and mounted on top of the motor. This assembly consists of an air

to water heat exchanger and separate motor driven fans. These are enclosed in heavy removeable steel

housings. The heat exchanger tube material is chosen based on analysis of samples of the proposed water

supply. The slip ring area has separate ventilation to assure no mixing of carbon dust laden air with main

cooling air. TWMC offers the follows cooling feature:

ENCLOSURE NEMA IEC IEC COOLING

Open Open IP00 IC-01

Weather Protected I WPI IP24 IC-01

Weather Protected II WPII IP24 IC-01

Totally Enclosed, Water to Air Cooled TEWAC IP54 ICW-86

Totally Enclosed, Air to Air Cooled TEAAC IP54 IC-48

Items also offered as options

In order to provide a complete hydro generator solution customers need, TECO-Westinghouse Motor

Company also offer the following equipments or service as options:

• Flywheel

• Brake system

• Excitation Control System

• Vibration or temperature sensors of bearings

• Oil lube system for Bearings

• Water cooling system for generator

• Field supervision for assembly, startup, and commissioning



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TECO-Westinghouse Motor Company’s Advantages

With over a Century of uninterrupted experience in the design and manufacture of large rotating

equipment for the power industry, TWMC has a very knowledgeable engineering and research staff.

Experienced in finite element analysis and design for electromagnetic, heat transfer, airflow, fluid, stress

and vibration problems on generators. We have an impressive number of modern computer programs in

house to perform these analyses. Based on our previous dealings with the other major power plants

TWMC has established a very good reputation in regard to our capabilities, performance based designs,

and ability to meet our contract dates.

Our modern generator manufacturing facility was specifically designed and constructed to accommodate

the custom manufacture of all types of large electrical rotating machines. It is without equal in the U.S. in

terms of its overall capabilities and features. Highlights include a 42,500 square meter climate controlled

manufacturing and testing area with over 9,000 square meters of heavy lift capacity. The maximum

overhead crane capacity of the Main Isle (A) largest crane is over 200 tons. A wide range of CNC

machining centers, lamination punching shop, stator coil factory, VPI process facility with multiple

ovens, and dedicated final assembly and test areas are all conveniently located within the Prime

Manufacturing building.

Since our primary business is the design and manufacture of large electric motors and generators, our

workforce has on average, in excess of 10 years experience. They are also cross-trained in a wide range of

skills. We have also a significant number of manufacturing personnel with 20+ years of experience

building and testing custom machines such as these.



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Exhibit 1: Recent Generator Experience List

PO

LE

S

ST

AT

OR

OD

CO

RE

LG

TH

KV

A P

OW

ER

VO

LT

S

PH

AS

E

HE

RT

Z

SF

PF

RP

M

EN

CL

OS

UR

E

16 108 39 15625 6900 3 60 1 0.8 450 OTD

16 108 39 15625 6900 3 60 1 0.8 450 OPEN 1

8 62.5 42 6050 6900 3 60 1 0.8 900 ODP

8 62.5 42 6054 6900 3 60 1 0.8 900 ODP

8 62.5 42 6050 6900 3 60 1 0.8 900 ODP

16 108 39 15625 6900 3 60 1 0.8 450 OPEN 1

8 62.5 42 6050 6900 3 60 1 0.8 900 ODP

8 62.5 42 6050 6900 3 60 1 0.8 900 ODP

6 62.5 42 9375 2400 3 60 1 0.8 1200 TEWAC 1

16 51 16 1500 1040 3 15 1 0.3 450 TEWAC

6 44 19 1750 450 3 60 1 0.8 1200 TEWAC

4 66 26 1500 1040 3 15 1 0.3 450 TEWAC

6 75 42 12000 12470 3 60 1 0.9 1200 TEWAC

30 128 33 6800 13800 3 60 1 0.8 240 ODP

30 128 33 6800 13800 3 60 1 0.8 240 ODP

16 108 39 15625 6900 3 60 1 0.8 450

Pitt Vent - open

4 66 26 1500 1040 3 15 1 - 450 TEWAC

12 75 28 5263 2400 3 60 1 0.95 600 WPII

14 93 35 10286 6600 3 60 1.05 0.7 514 TEWAC 1

14 93 35 10286 6600 3 60 1.1 0.7 514 TEWAC 1

8 71 24 1875 450 3 60 1 0.8 900 TEWAC

4 66 26 1500 1040 3 15 1 0.8 450 TEWAC

12 108 49 19853 11000 3 50 1 0.8 500 DP

4 62.5 43 9500 11400 3 60 1 - 1800 TEFV

18 85 32 - 4160 3 60 1 0.8 400 ODP

20 93 36 7300 6600 3 60 1 0.9 360 ODP

4 66 26 1500 1040 3 15 1 0.3 450 TEWAC

20 93 36 5000 3300 3 60 1 0.8 360 TEFV



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Exhibit 2: Excitation Control Panel

Typical Specifications:

This is for the use with a brushless synchronous machine. Power output is rated to 15 Amperes continuous at up to 125 Volts,

with ten-second forcing rating of 30 Amperes at 200 Volts - suitable for operation at temperatures to 40°C at altitudes to 1000

meters.

NEMA 1 Enclosure measuring approximately 30” x 30” x 90” and weighing approximately 350kg/750 lbs. Includes:

DECS-200SMC:

1. DECS-200 digital controller, Door Mounted, with the following features and functions:

Var and Power Factor Controller

Field Current Regulator

Voltage Regulation 0.25%, true RMS sensing

Power Bridge-15 Ampere Capacity

Under excitation limiter (UEL)

Stator Current Limiter (SCL)

Over excitation limiting (OEL)

Protection

Over/undervoltage

Field overvoltage

Field overcurrent

Loss of voltage sensing to internal FCR Mode (Manual)

Rotating Diode Fault Detector (ripple detector)

Metering, real time at local LCD or at personal compute

Reference Adjusters: AVR, FCR, Var/PF

Preposition setpoints (maintain or release)

Setpoint position indication

RS-485 communication for monitoring, annunciation, control

Control

Front panel keypad switches

Provisions for external hardwired contacts and switches

Software through personal computer

2. PRP-320 Synchronous Motor Pullout Relay

3. Incomplete Sequence Timer Relay

4. Independent Field Over/Undercurrent relay trip

BE3-74SD

DC Ammeter Shunt

5. Field Voltage Surge Arrestor

6. Remote Interface

AC field start/stop relay

Contact annunciation

Protective Trip – Watchdog

FCR Mode

Limiter Active

General Protection

Regulator “ON”

7. ICRM-15 Inlet Current Reducing Module

8. Local Control Switch

S1 FCR Select Switch

9. 20% Spare Terminal Points

introduction of synchronous generators technology syn hydro technical introduction_1.pdf · rotor:...

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