WEG Welcomes

For

Presentation on

Quality aspects of Hydro-Generators

Date: 06.01.2018

0

Our History September 16th, 1961

Back in 1961, Werner Ricardo

Voigt, Eggon João da Silva and

Geraldo Werninghaus decided to

join efforts to create a company.

Werner Ricardo Voigt

Eggon Joao da Silva

Geraldo Werninghaus

These men did not just create a

company. They created a

complete culture of doing

business that is focused on

people.

WEG INDUSTRIES (INDIA) PVT. LTD. ,FACTORY VIEW

-Total land area : 146,500 m2

-Total build up area : 30,000 m2

- Production Capacity : 25 units/

month.

- Crane : 14 cranes

Capacity (10, 20, 40, 60and 80

tons)

- Total Investment : 70 million

(US$)

-Main building : 300 m x 65 m

- Power Back up : 2.25 MW

- Investment in Training :

US$ 350,000

- 50 Indians trained at Brazil

- 50 Brazilians trained Indian

Personnel

Front View of Factory

View from the Gate Machines in Test Lab

WHY ?

v

Technology

Capability

Reliability

Reputation

Quality

Customer Friendly

Design

Mfg.

Process

• Complete In-House manufacturing – Total process under control.

• Special process in Fabrication

• Special welding technology

• Special process for heat treatment & stress reliving

• In-House stamping manufacturing – flexibility in design & Performance.

• Special test on core materials and insulation materials .

• Global VPI system

•Accuracy in machining with CNC Machines

•Highly special shaft manufacturing consoles

•State of Art grinding machine for perfect finish

•In-house tool grinding facilities

•Special technic for core building process

•Special knowledge on balancing applied

•Ease of maintenance and repair

•Installation and commissioning support through expert team

•Detail guideline in E&C Manual.

•Customer interaction and training

• Software's for

• Electrical and Magnetic Design.

• Insulation system

• Mechanical & Structural Design

• Bearing Lubrication system

• Noise & aquatics

• Vibration

TECHNOLOGY

APPLICATION / INDUSTRY KNOWLEDGE

Generators for

All types of Hydro turbines

All types of steam/Gas

turbine

Horizontal / Vertical

All types of enclosures

Salient / Cylindrical

Poles

Special knowledge on Seismic

zone operation

RESOURCES & CAPABILITY

Resources &

Capability

Trained manpower at different

levels

Highly equipped

design team & interlink with

HQ Brazil

Qualified operators for

special operations (like – welding and

special machining etc)

Special lean flow process

and knowledge

Adherence to global quality

standards

WEG SCOPE OF SUPPLIES FOR HYDRO POWER PLANT

WEG can Supply :

Generator (Both Horizontal and Vertical) Excitation System Lubrication Oil System

Output: Up to 50,000 kVA

Frame: 450 to 4000 (IEC)

Voltage: up to 13,800 V

Hydro Generators

S Line

Poles: 4 and above

Mounting: Horizontal & Vertical

TECHNOLOGY APPLIED TO

ENGINEERING/DESIGN

ENGINEERING

ELECTROMAGNETIC

DESIGN

THERMAL AND NOISE

ANALYSIS

MECHANICAL

DESIGN

SOFTWARES • OTIMEC

• Preliminary Model

• Preliminary design

• RENK

• Sleeve bearing cal.

• SKF website

• Antifriction bearing cal.

• ROTODIN

• Preliminary calculation

• Detail calculation

• MATHCAD

• Torsional critical speeds

• Torque transmission capacity

• Preliminary Deflection calculation

• Flywheel Stresses calculation

• EXCEL calculations

• Heat exchangers calculations

• Brake calculations

• Gross mass calculations

• AUTOCAD

• Preliminary Dimensional Drawing

• ASSOM – Data sheets

• SAP – Data exchange

ROTORDIN -INPUT

RENK -OUTPUT RENK -INPUT

CAMBELL Diagram

ROTORDIN -OUTPUT

System Responce

ROTORDIN -OUTPUT

Orbit-Mode Shape

ROTORDIN -OUTPUT ROTORDIN -OUTPUT

SOFTWARE - OTIMEC

It is preliminary design software used to model the generator to

perform Various type of calculations.

It is integrated Calculation software which perform Various

calculation such as • Sleeve Bearing calculation (RENK interface)

• Flywheel Stress calculation

• Initial Static/ Dynamic Deflection Calculation

• Loading Calculation over supports

• Approximate 1st un-damped Critical speed

• Modelling of various type of Salient Pole construction

• Modelling Cylindrical Pole construction

• Inertia/ GD2 calculation

• Optimization of designs with graphical interphase

RENK -INPUT RENK -OUTPUT

SOFTWARE - ROTORDIN

It is Advance design software used to perform Advance rotor

Dynamic Calculation

Software Can perform:

• CAMPLELL Diagram

• Unbalance system Response Curve for Given Speed Range

• Detail Static as well as dynamic Deflections.

• Un- Damped as well as Damped Natural Frequencies.

• Un- Damped as well as Damped Critical Speeds.

• Calculation N-Number of Mode shapes

• 3-Dimension Shaft whirl profile corresponding to mode.

CAMPBELL Diagram

Unbalance Response

Solid Shaft Model Finite differential Shaft Model

3-D Mode Shape @ Natural Freq.

SOFTWARE - CRITICAL CALCULATION Critical Calculation in advance stages will be analysed in FEA

FEA software ANSYS:

TECHNOLOGY APPLIED TO

ELECTROMAGNETIC ANALYSIS

Engineering ELECTROMAGNETIC ANALYTICAL TOOLS

Use of electromagnetic calculation tools to improve the productivity and design of

electric motors and generators

Global software available to all WEN engineering around the world

- INDUCTION &

FLUX

Stator core & teeth

Rotor core & teeth

- EFFICIENCY 25% / 50% / 75% / 100% of load

- LOSSES Winding

Iron

Stray

Mechanical

- INSULATION Voltage withstand & Impulse

ELECTROMAGNETIC DESIGN

- LOCKED ROTOR Current

Torque

- ACCELERATION Acceleration time

Stator Current during acceleration

40 40 40 40 40

60 75 80

100

125 5

5 10

15

15

CLASS A CLASS E CLASS B CLASS F CLASS H

Ambient Temperature (40 deg C) temperature Rise Hot Spot Temperature

22

INSULATION CLASS AND TEMPERATURE RISE

Insulation system

Insulation system WEG MICATHERM

VPI system with epoxy resin (solvent free), with insulation capacity

monitored during the whole impregnation process.

Class F (155°C) insulation machine and class F or class B , temperature

rise allowing extended insulation life time

COMPONENTS AND MANUFACTURING PROCESSES

25

THERMAL EVALUATION

TEMPERATURE RISE

SIMULATION OF TEMPERATURE RISE

IN IRON AND WINDING BY SASVPI

TEMPERATURE

Stator winding

Rotor winding

Air flow inside machine

Air pressure

Fan efficiency

Losses (friction & ducts)

TECHNOLOGY APPLIED TO

MECHANICAL DESIGN

DESIGN TECHNOLOGY MECHANICAL DESIGN

- SHAFT BEARING SELECTION

- BEARING TEMPERATURE & LIFE

CALCULATIONS

-SHAFT STRESS CALCULATION

-ROTOR CRITICAL SPEED CALC.

-FLUID FLOW ANALYSIS

-COOLING /VENTILATION

CALCULATION;

-BASE LOADS CALCULATION

- TORSIONAL ANALYSIS

-MACHINE PARTS STRUCTURAL

ANALYSIS

-DESIGN GUIDELINES

28

BEARING CALCULATION

Sleeve Bearings: - Effective lubricant film temperature;

- Frictional power loss;

- Lubricant film stiffness coefficients;

- Lubricant film damping coefficients;

- Hydrodynamic required flow rate.

INPUT DATA

OUTPUT DATA

Anti-Friction Bearings: - L10h bearing life;

- Re-lubrication interval;

- Re-lubrication grease quantity.

BEARING SELECTION

29

DESIGN TECHNOLOGY MECHANICAL BASIC DESIGN

SHAFT STRESS CALCULATION

-Fatigue analysis;

-Static analysis;

-Loads:

- Start up;

- Rated speed.

- Runaway speed

ANALYTICAL

CALCULATION

PROCEDURES -ANALYTICAL CALCULATION USING SPECIFIC

CALCULATION PROCEDURES;

-FINITE ELEMENTS SIMULATIONS. FINITE ELEMENTS

SIMULATIONS

ROTOR DYNAMICS

Shaft natural frequencies and responses

Campbell diagram

Prediction of rotor unbalance consequences

Fluid Dynamics

Numerical simulation :

Machine overall cooling using ANSYS CFX

Component and rotor geometry optimization to

reach the best performance

FLUID FLOW ANALYSIS

MECHANICAL BASIC DESIGN

BASE LOADS CALCULATION

-Base loads at rated load:

- Static forces;

- Dynamic forces;

- Turbine load.

-Base loads in case of fault;

- Dynamic forces at three phase short circuit;

- Dynamic forces at phase to phase short circuit;

- Dynamic forces at synchronizing out-of-phase;

CALCULATION PROCEDURES

-ANALYTICAL CALCULATION USING

SPECIFIC CALCULATION PROCEDURE

MECHANICAL & STRUCTURAL DESIGN

Use of Analysis for numerical simulation

Stress, fatigue and modal analysis

Mechanical optimization of components

Numerical simulation of Mechanical - Structural

NOISE CALCULATION

ALFRED/AGR

ANALISYS OF THE AIR-GAP FIELD OF

MULTI-PHASE ELECTRICAL MACHINE

GENERAL NOISE PREDICTION

- Natural frequencies

- Spatial harmonics of flux density

- Origin of flux density harmonics

35

Design : Dedicated software - ensures the rotor natural frequencies are

well out of the operating range to avoid resonance.

Check upto 3rd harmonic of the operating speed & 2nd harmonic of the

line frequency.

Consideration of bearing and support stiffnesses at operating temp.

Deflection is restricted to maximum 5% of airgap.

VIBRATION:

TECHNOLOGY FOCUS

ON

INERTIA

Synchronous Motor

INERTIA CONSTANT (H)

Definition

(kVA)

)2

(tm(rpm)

kVA) /(kWs

N

2N

2

P*1800

J*N*H

2mr2

1J

Equation

Ratio between energy and the output power.

Represents storaged energy per kVA.

METHODS TO INCREASE THE INERTIA

Increase rotor external diameter (increase stator internal

diameter)

Stator for a rotor with natural inertia

IEC Frame 900 (580 kg.m2)

Stator for a rotor with higher inertia

IEC Frame 1120 (1000 kg.m2)

Higher windage losses

Higher mechanical losses

TECHNOLOGY APPLIED TO

ELECTRICAL DESIGN

RATING AND GENERATOR SIZING

Generator Rating: Generators are rated in KVA and power factor.

This needs special consideration.

Speed: The speed of generator is decided by turbine speed or type

of turbine.

FACTORS AFFECTING GENERATOR SIZE :

Power output (kVA): Generator size will increase with power output

to maintain the magnetic and electric loading.

Speed: Lower the speed of the machine bigger is the size delivering

same power.

Altitude: Machines installed at higher altitude will increase size of

the machine since altitude will effect cooling

Inertia: Higher inertia requirement to improve stability will lead to

higher mass and higher is the machine size

Power Factor: Poor power factor requires higher field input due to

the effect of armature reaction and bigger size of field coils

GENERATOR OVERLOAD

The continuous over load of the generator will increase temperature

rise , so need to limit thermal.

Continuous over load is indicated by service factor

Performance of the machine is offered at rated conditions but thermal

is limited considering the overload.

Short circuit ratio is achieved at rated conditions, as SCR drops at

overload.

EFFICIENCY CURVE

Efficiency will increase with load till peak point and then drops as

shown in the curve.( Below curve is plot between efficiency and Load

in %)

The poor power factor of the machine increases the losses in rotor

and drops the efficiency . The Iron Losses and mechanical losses

remain constant but the copper losses increase with load

The efficiency will increase the price of the machine since the losses

need to be reduced

SHORT CIRCUIT RATIO REQUIREMENT:

Advantages of higher SCR value:

• The generator will have a more stable operation when connected to the grid

• Better voltage regulation

• Lower noise

Effects of higher SCR value:

• The machine should be designed with a higher air gap, increasing the size

and cost of the machine

• Higher short circuit currents

• Higher temperatures in the rotor leading to increased copper quantity

Synchronous Motor

Increase the airgap Larger airgap increase the field leakage. This will

demand more copper in rotor winding.

METHODS TO INCREASE THE SHORT CIRCUIT RATIO (SCR)

Increase the flux Increase the flux will saturate the machine

magnetic circuit demanding more active parts

SUB TRANSIENT DIRECT AXIS REACTANCE (𝑿𝒅" ) – REQUIREMENT :

HYDROGENERATORS

When a three phase fault occurs in a synchronous machine, the current instantly

rises to a very high value, falls to intermediate value and then settles at a lower

steady state fault value. A typical fault current oscillogram is shown below :

With a generator operating at full voltage, a symmetrical 3-phase short circuit at

its terminals will cause a large amount of current to flow. This initial current is

used to determine the required interrupting rating of overcurrent devices, circuit

breakers and fuses, located at the generator(s). The initial instantaneous

current value (I"fault ) is controlled by the sub-transient reactance (X"d) and is

expressed as the voltage divided by the sub-transient reactance.

I"fault a 𝑉𝑎𝑐 𝑋"𝑑

COST - EFFECTIVE DESIGN

Natural Inertia :

Double-check power system stability studies to request

natural H, Large inertia increase the generator frame

Natural SCR :

High SCR increase the generator active parts or oversize

the copper

TECHNOLOGY APPLIED TO

PROCESSES

60 08/01/2018

COMPLETE IN-HOUSE MANUFACTURING

COMPONENTS AND MANUFACTURING PROCESSES

Frame

Wounded Stator

Coils

Rotor

Impregnation

Bearings

Accessories

Excitation

COMPONENTS AND MANUFACTURING PROCESSES

Welded steel structure which provides mechanical support and protection to the Generators.

Frame

COMPONENTS AND MANUFACTURING PROCESSES

Consists of a low loss silicon lamination core and the stator winding,

which is connected to an AC power supply in order to provide the

rotating magnetic field.

Wounded Stator

COMPONENTS AND MANUFACTURING PROCESSES

Coils

Manufactured with rectangular copper wires, using an automatic process

Insulated with mica tape, semi-conductive and conductive tapes

Impregnated with epoxy resin (without solvent) through VPI system (WEG micatherm

system)

Inserted into the core slots and fixed with fiber glass or magnetic wedges;

The high potential test and short circuit between turns test (surge test) are performed

before and after the stator impregnation process

COMPONENTS AND MANUFACTURING PROCESSES

Rotor - Laminated Salient Poles

Manufactured with steel laminated plates

The field winding is made of copper wires / bars

individually insulated

The poles are manufactured separately and

fixed to the shaft usually with screws or dove

tail

The cage bars are inserted into the pole shoes

and short circuited at both ends through the

short-circuit ring.

COMPONENTS AND MANUFACTURING PROCESSES

Rotor - Cylindrical Poles

The cylindrical rotor is composed by a non

segmented laminated core mounted on the

shaft.

The field winding is manufactured with

insulated rectangular copper wires

The coils are inserted into core slots and

fixed with proper wedges

The amortisseur winding (brass or copper

bars) are placed into the rotor slots and short

circuited at their ends by short circuit rings

COMPONENTS AND MANUFACTURING PROCESSES

Impregnation

Vacuum Pressure Impregnation System (VPI)

WEG MICATHERM Insulation system

Vacuum and pressure impregnation (VPI)

with epoxy resin (without solvent)

Insulation capacitance monitored during all

impregnation process

COMPONENTS AND MANUFACTURING PROCESSES

Bearings

Ball or Roller Bearings

Grease lubricated

Oil lubricated

Ball or Roller Bearings Sleeve bearings

naturally lubricated Sleeve bearings with

forced lubrication

Grease lubricated

Oil lubricated

When the rotor turns, the

lubrication oil is distributed by the

internal oil ring and transferred

directly to the shaft surface

creating a layer of oil between

the shaft and the bearing liner

surface

The oil heat is dissipated only

through radiation or convection

The lubricating oil circulates in the

bearings through an independent

external system, which is also

responsible for the oil cooling

This system is required when

natural lubrication / cooling is not

sufficient, specially due to high

speed operation and high friction

losses

COMPONENTS AND MANUFACTURING PROCESSES

Ball or Roller Bearings

Grease lubricated

Oil lubricated

Exciter

Supplies the magnetizing DC current to the motor field winding

Types of Excitation:

Static – with brushes

Brushless – without brushes

ROUTINE TESTS

Resistance measurement of all windings

Insulation resistance measurement before

and after HV

High Voltage test on all windings

Open Circuit and short circuit characteristics

Efficiency test by summation of losses

method.

Phase sequence

Voltage balance

Rotor impedance

Functional check of accessories with

Generator

TYPE TESTS

Open Circuit Heat run

Short Circuit Heat run

Momentary Over Current Test

Sudden Short Circuit test @ 30% rated voltage

Noise Level test

Recording of no load wave form, harmonics and THF

calculation

Determination of reactance values by sudden short

circuit test

Vibration measurement

Shaft voltage

Over speed test

Retardation Test

STANDARD TESTS The following are the Preferred tests conducted as per IEC 60034-4

Quantity Test Description

Synchronous Reactance (Xd) No- load saturation, sustained

Three phase short circuit

Direct-axis Transient Reactance

(Xd’),

Direct Axis Sub transient

Reactance(Xd”)

Sudden three phase short circuit

Quadrature Axis Synchronous

Reactance (Xq)

Negative Excitation

Quadrature Axis sub transient

Reactance (Xq”)

Applied voltage test with rotor in

direct and quadrature axis

Zero Sequence Reactance (X0) Single phase voltage application to

three phases

Negative sequence Reactance (X2) Line-Line Sustained Short Circuit

Quantity Test Description

Armature Resistance Ammeter Voltmeter

Zero Sequence Resistance Single phase voltage application to

three phases

Armature Short circuit Time constant Sudden three phase short circuit

Direct Axis Transient & sub Transient

short circuit time constant

Sudden three phase short circuit

Direct Axis Transient Open circuit time

constant

Field current decay with armature

winding open circuited , at rated speed

THANK YOU

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