Title of Invention	AN ALTERNATOR FOR HIGH POWER DIESEL ELECTRIC LOCOMOTIVES FOR TRACTION APPLICATION
Abstract	The invention relates to an alternator for 2500 to 3000 HP diesel electric locomotive for traction application with high power to weight ratio, which is enabled to convert the mechanical power received from the diesel engine and to generate A.C. electric power and having a rectifier unit to convert the solid A.C. power in the D.C. power an auxiliary generator, an exciter, a power take off unit, the traction alternator being driven by a gear train device, characterized in that the rectifier is mounted on the traction alternator, and in that the auxiliary generator, the exciter, and the power take off unit are mounted on the gear train.

Title of Invention

AN ALTERNATOR FOR HIGH POWER DIESEL ELECTRIC LOCOMOTIVES FOR TRACTION APPLICATION

Abstract

The invention relates to an alternator for 2500 to 3000 HP diesel electric locomotive for traction application with high power to weight ratio, which is enabled to convert the mechanical power received from the diesel engine and to generate A.C. electric power and having a rectifier unit to convert the solid A.C. power in the D.C. power an auxiliary generator, an exciter, a power take off unit, the traction alternator being driven by a gear train device, characterized in that the rectifier is mounted on the traction alternator, and in that the auxiliary generator, the exciter, and the power take off unit are mounted on the gear train.

Full Text	FIELD OF INVENTION The present invention relates to a traction alternator to work on various application ratings in the range of 2500-3000 HP mechanical power input from diesel engine for application in high horse power Diesel Electric locomotives. More particularly, the present invention relates to an improved system for generating high power to drive a locomotive. BACKGROUND OP INVENTION The substantial parts of rail routes in India and abroad are not electrified. Essentially diesel electric locomotives operate in these routes. In a diesel locomotive, there is a diesel engine couple with generator to work as mobile power house to provide electric power for feeding the traction motors which drive the wheels. Earlier the diesel locomotive was provided with DC generator (Fig. 1) coupled with diesel engine to cater for electrical power to traction motors. It was able to develop limited power at lower voltage as compared to AC alternators. To overcome these issues, the new product traction alternator (Fig.2) has been developed which is capable of delivering higher power within same frame size and also generates higher voltage to operate the locomotive at higher KPH. The elimination of large no. of brushes & commutator as compared to DC generator renders higher reliability and lesser maintenance. The production cycle is also shorter and the cost of machine is also less as compared to similar size generator. The comparison of features of the prior art machine and the new machine is as per table below: The comparison of power ratings of DC gen. and the AC alt. after considering the rectification losses etc. for the same frame size is furnished as below in tabular form: OBJECTS OF INVENTION It is an object of the present invention to provide a higher horse power alternator. Another object of the invention is to develop an alternator which enables the loco to operate at higher HP, higher starting torque and higher KFH. Yet another object of the invention is to provide more reliable AC alternator to customer and reduction of maintenance as compared to DC generator. SUMMARY OP THE INVENTION Accordingly there is provided an improved system for generating high power to drive locomotives which takes mechanical power from diesel engine and generates AC power which is further rectified to DC to feed the motors which drive the locomotive and runs the train. The alternator also has built in small DC generator for its field excitation and another small DC generator for auxiliary power supply of the loco. The alternator also incorporates several improved constructional features based on service experience on the prior art. A notable feature of the new alternator is the adoption of improved auxiliary generator and exciter type AG 3101AY - 1 (with series parallel arrangement of shunt field coils for better battery charging at low rpm). A sturdy power take off unit type PT70AZ is also provided for driving heavy duty FTM blower (front traction motors blower). BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS: 1. Fig. 1. shows earlier D.C. generator. 2. Fig. 2. shows the Present A.C. Alternator. 3. Fig. 3. shows the block diagram of Traction Alternator. DETAIL DESCRIPTION OF THE INVENTION: The alternator details are shown as per block diagram in Fig 3. The alternator (1) is connected to a gearbox (2). Two Nos. aux. generators (3) are mounted on this gearbox (2). Initially at the time of cranking of diesel engine of the loco, these two generators (3) work as prime mover motor and rotate the diesel engine crankshaft by taking power from battery bank (4). Afterward these two machines work as generators. One machine work as exciter to alternator by supplying power to rotor field coils via excitation control system. The other works as aux. generator which charges the battery bank and also supplies to aux. Loads of the locomotive engine. Further constructional details of alternator are as described below:- STATOR: Low loss high quality electrical sheet steel segmental punchings are built on insulated stator core studs between core and end plates which are welded to stator ribs inside the stator frame. The frame is a rolled steel barrel with axial and circumferential reinforcing steel ribs. Coupling lugs, lifting lugs and resting flags welded on to it A 10-pole, 2-layers, 3-phase, star connected, were winding with two parallel circuits per phase, is housed in open type stator slots. Single turn stator coils are Class 'H' insulated. Bach stator conductor is sub-divided in depth into six sections to limit the eddy losses. The insulation of stator coils have been strengthened by using PTPB tape for an insulation level of 1500 V. The three terminals of the stator winding are brought out through the cut-outs in frame in the form of copper bus-bars inside the terminal box. The neutral connection is also brought out to terminal box to facilitate the connection of ground relay and better ground fault protection. The fabricated end-shield is spigoted and bolted to the stator. Three large air- inlets cum inspection opening with perforated covers have been provided on the end shield to facilitate inspection and maintenance in service. Brush gear assembly and bearing housing are mounted on the end shield. ROTOR: The rotor hub is a steel barrel with driving flange welded on one end. On the non-driving end a shaft extension and disc assembly is spigoted and bolted onto the rotor barrel. The ten laminated rotor poles are mounted on the round rotor hub and bolted from inside of the rotor hub. The fan is spigoted and bolted onto the rotor hub on driving end. The rotor assembly is solidly coupled to the diesel engine crank shaft and the other end of the shaft supported on a cylindrical roller bearing housed in the end shield. The Class 'H' insulated Field Coils are of edge-wound design, made out of a continuous copper strip. Coil to coil connections are of brazed type. The field connections are supported on a common tie- ring, which is firmly secured to the rotor hub. VENTILATION SYSTEM: The alternator is ventilated by the fan. The ventilation air is drawn into the alternator through the air-inlets, provided on the alternator end shield and stator peripheral openings at non-driving end AUXILIARY DRIVE ARRANGEMENT: A gearbox is mounted on the non-driving end of the non-driving end of the alternator, which holds and drives the exciter, auxiliary generator and traction motor blower through the power take-off unit. The bull-gear of the gear drive is so designed to transmit the required cranking torque of the diesel engine, when auxiliary generator and exciter are used as starting motors. The bull gear, pinion, bearing and the drive end bearings of auxiliary machines and PTU are oil-lubricated with the gearbox oil. The idler gear assembly provides continuous circulation of lubricating oil. WE CLAIM : 1. An alternator for 2500 to 3000 HP diesel electric locomotive for traction application with high power to weight ratio, which is enabled to convert the mechanical power received from the diesel engine and to generate A.C. electric power and having a rectifier unit to convert the solid A.C. power in the D.C. power an auxiliary generator, an exciter, a power take off unit, the traction alternator being driven by a gear train device, characterized in that the rectifier is mounted on the traction alternator, and in that the auxiliary generator, the exciter, and the power take off unit are mounted on the gear train. 2. The alternator as claimed in claim - 2 wherein the stator of the alternator is housed in a stator frame made of a rolled steel barrel with axial and circumferential reinforcing steel ribs. 3. The alternator as claimed in claim 1, wherein the stator comprises low loss high quality electrical sheet steel segmental punchings built on insulated core studs between the stator core end plates, which are welded to stator ribs inside the stator frame. 4. The alternator as claimed in claim 3, wherein the stator has a plurality of open type stator slots and a 10-pole, 2-layers, 3-phase star connected, wave winding including two parallel circuits per phase, is housed in the slots, wherein single turn stator colls are of class "H" insulated with each stator conductor sub-divided in depth into six sections to limit the eddy losses, and wherein the insulated stator coils are strengthened by using PTFE tape to achieve an insulating level of 1500V. 5. The alternator as claimed in claim 4, wherein three terminals of the stator winding are brought out through cut - outs formed in the stator frame in the form of copper bus-bars inside the terminal box, and wherein the neutral connection is also brought out to the terminal box, the end sehield being spigoted and bolted to the stator. 6. The alternator as claimed in claim 5, wherein at least three large air-inlets cum inspection opening with perforated covers are provided at the end shield and brush gear assembly and wherein the bearing housings are mounted on the end-shield. 7. The system as claimed in claim - 1, where in the rotor hub a steel barrel driving flange welded on one end and on the non-driving end a shaft extension and dise assembly is spigoted and bolted on to the rotor barrel, wherein the laminated rotor poles including a fan are mounted on the round rotor hub and wherein the rotor assembly is coupled to a first end of the diesel engine crank shaft and the second end of the shaft is supported on a cylindrical roller bearing housed in the end shield. 8. The alternator as claimed in claim - 7 wherein the field coils of the rotor are of the class "H" insulated and are of edge - wound design, made out of a continuous copper strip, and wherein the field connections are supported on a common tie - ring which is firmly secured to the rotor hub. 9. An alternator for 2500 to 3000 HP diesel electric locomotive for traction application with high power to weight ratio, which is enabled to convert the mechanical power received from the diesel engine and to generate A.C. electric power and having a rectifier unit to convert the solid A.C. power in the D.C. power an auxiliary generator, an exciter, a power take off unit, the traction alternator being driven by a gear train device, characterized in that the rectifier is mounted on the traction alternator, and in that the auxiliary generator, the exciter, and the power take off unit are mounted on the gear train as substantially described and illustrated herein with reference to the accompanying drawings.

Full Text

FIELD OF INVENTION
The present invention relates to a traction alternator to work on
various application ratings in the range of 2500-3000 HP mechanical
power input from diesel engine for application in high horse power
Diesel Electric locomotives. More particularly, the present invention
relates to an improved system for generating high power to drive a
locomotive.
BACKGROUND OP INVENTION
The substantial parts of rail routes in India and abroad are not
electrified. Essentially diesel electric locomotives operate in these
routes. In a diesel locomotive, there is a diesel engine couple with
generator to work as mobile power house to provide electric power
for feeding the traction motors which drive the wheels.
Earlier the diesel locomotive was provided with DC generator (Fig.
1) coupled with diesel engine to cater for electrical power to traction

motors. It was able to develop limited power at lower voltage as
compared to AC alternators. To overcome these issues, the new
product traction alternator (Fig.2) has been developed which is
capable of delivering higher power within same frame size and also
generates higher voltage to operate the locomotive at higher KPH.
The elimination of large no. of brushes & commutator as compared
to DC generator renders higher reliability and lesser maintenance.
The production cycle is also shorter and the cost of machine is also
less as compared to similar size generator. The comparison of
features of the prior art machine and the new machine is as per table
below:

The comparison of power ratings of DC gen. and the AC alt. after
considering the rectification losses etc. for the same frame size is
furnished as below in tabular form:

OBJECTS OF INVENTION
It is an object of the present invention to provide a higher horse
power alternator.
Another object of the invention is to develop an alternator which
enables the loco to operate at higher HP, higher starting torque and
higher KFH.
Yet another object of the invention is to provide more reliable AC
alternator to customer and reduction of maintenance as compared to
DC generator.
SUMMARY OP THE INVENTION
Accordingly there is provided an improved system for generating
high power to drive locomotives which takes mechanical power from
diesel engine and generates AC power which is further rectified to
DC to feed the motors which drive the locomotive and runs the train.
The alternator also has built in small DC generator for its field

excitation and another small DC generator for auxiliary power supply
of the loco.
The alternator also incorporates several improved constructional
features based on service experience on the prior art. A notable
feature of the new alternator is the adoption of improved auxiliary
generator and exciter type AG 3101AY - 1 (with series parallel
arrangement of shunt field coils for better battery charging at low
rpm). A sturdy power take off unit type PT70AZ is also provided for
driving heavy duty FTM blower (front traction motors blower).
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
1. Fig. 1. shows earlier D.C. generator.
2. Fig. 2. shows the Present A.C. Alternator.
3. Fig. 3. shows the block diagram of Traction Alternator.
DETAIL DESCRIPTION OF THE INVENTION:
The alternator details are shown as per block diagram in Fig 3. The

alternator (1) is connected to a gearbox (2). Two Nos. aux.
generators (3) are mounted on this gearbox (2). Initially at the time
of cranking of diesel engine of the loco, these two generators (3)
work as prime mover motor and rotate the diesel engine crankshaft
by taking power from battery bank (4). Afterward these two
machines work as generators. One machine work as exciter to
alternator by supplying power to rotor field coils via excitation
control system. The other works as aux. generator which charges
the battery bank and also supplies to aux. Loads of the locomotive
engine.
Further constructional details of alternator are as described below:-
STATOR:
Low loss high quality electrical sheet steel segmental punchings are
built on insulated stator core studs between core and end plates
which are welded to stator ribs inside the stator frame. The frame is
a rolled steel barrel with axial and circumferential reinforcing steel
ribs. Coupling lugs, lifting lugs and resting flags welded on to it

A 10-pole, 2-layers, 3-phase, star connected, were winding with
two parallel circuits per phase, is housed in open type stator slots.
Single turn stator coils are Class 'H' insulated. Bach stator
conductor is sub-divided in depth into six sections to limit the eddy
losses. The insulation of stator coils have been strengthened by
using PTPB tape for an insulation level of 1500 V.
The three terminals of the stator winding are brought out through the
cut-outs in frame in the form of copper bus-bars inside the terminal
box. The neutral connection is also brought out to terminal box to
facilitate the connection of ground relay and better ground fault
protection.
The fabricated end-shield is spigoted and bolted to the stator.
Three large air- inlets cum inspection opening with perforated
covers have been provided on the end shield to facilitate inspection
and maintenance in service. Brush gear assembly and bearing
housing are mounted on the end shield.

ROTOR:
The rotor hub is a steel barrel with driving flange welded on one
end. On the non-driving end a shaft extension and disc assembly is
spigoted and bolted onto the rotor barrel. The ten laminated rotor
poles are mounted on the round rotor hub and bolted from inside of
the rotor hub. The fan is spigoted and bolted onto the rotor hub on
driving end. The rotor assembly is solidly coupled to the diesel
engine crank shaft and the other end of the shaft supported on a
cylindrical roller bearing housed in the end shield.
The Class 'H' insulated Field Coils are of edge-wound design, made
out of a continuous copper strip. Coil to coil connections are of
brazed type. The field connections are supported on a common tie-
ring, which is firmly secured to the rotor hub.
VENTILATION SYSTEM:
The alternator is ventilated by the fan. The ventilation air is drawn

into the alternator through the air-inlets, provided on the alternator
end shield and stator peripheral openings at non-driving end
AUXILIARY DRIVE ARRANGEMENT:
A gearbox is mounted on the non-driving end of the non-driving end
of the alternator, which holds and drives the exciter, auxiliary
generator and traction motor blower through the power take-off unit.
The bull-gear of the gear drive is so designed to transmit the
required cranking torque of the diesel engine, when auxiliary
generator and exciter are used as starting motors. The bull gear,
pinion, bearing and the drive end bearings of auxiliary machines and
PTU are oil-lubricated with the gearbox oil. The idler gear
assembly provides continuous circulation of lubricating oil.

WE CLAIM :
1. An alternator for 2500 to 3000 HP diesel electric locomotive for traction
application with high power to weight ratio, which is enabled to convert
the mechanical power received from the diesel engine and to generate
A.C. electric power and having a rectifier unit to convert the solid A.C.
power in the D.C. power an auxiliary generator, an exciter, a power take
off unit, the traction alternator being driven by a gear train device,
characterized in that the rectifier is mounted on the traction alternator,
and in that the auxiliary generator, the exciter, and the power take off
unit are mounted on the gear train.
2. The alternator as claimed in claim - 2 wherein the stator of the alternator
is housed in a stator frame made of a rolled steel barrel with axial and
circumferential reinforcing steel ribs.
3. The alternator as claimed in claim 1, wherein the stator comprises low
loss high quality electrical sheet steel segmental punchings built on
insulated core studs between the stator core end plates, which are welded
to stator ribs inside the stator frame.
4. The alternator as claimed in claim 3, wherein the stator has a plurality of
open type stator slots and a 10-pole, 2-layers, 3-phase star connected,
wave winding including two parallel circuits per phase, is housed in the
slots, wherein single turn stator colls are of class "H" insulated with each
stator conductor sub-divided in depth into six sections to limit the eddy
losses, and wherein the insulated stator coils are strengthened by using
PTFE tape to achieve an insulating level of 1500V.
5. The alternator as claimed in claim 4, wherein three terminals of the stator
winding are brought out through cut - outs formed in the stator frame in
the form of copper bus-bars inside the terminal box, and wherein the
neutral connection is also brought out to the terminal box, the end sehield
being spigoted and bolted to the stator.
6. The alternator as claimed in claim 5, wherein at least three large air-inlets
cum inspection opening with perforated covers are provided at the end
shield and brush gear assembly and wherein the bearing housings are
mounted on the end-shield.
7. The system as claimed in claim - 1, where in the rotor hub a steel barrel
driving flange welded on one end and on the non-driving end a shaft
extension and dise assembly is spigoted and bolted on to the rotor barrel,
wherein the laminated rotor poles including a fan are mounted on the
round rotor hub and wherein the rotor assembly is coupled to a first end
of the diesel engine crank shaft and the second end of the shaft is
supported on a cylindrical roller bearing housed in the end shield.
8. The alternator as claimed in claim - 7 wherein the field coils of the rotor
are of the class "H" insulated and are of edge - wound design, made out
of a continuous copper strip, and wherein the field connections are
supported on a common tie - ring which is firmly secured to the rotor
hub.
9. An alternator for 2500 to 3000 HP diesel electric locomotive for traction
application with high power to weight ratio, which is enabled to convert
the mechanical power received from the diesel engine and to generate
A.C. electric power and having a rectifier unit to convert the solid A.C.
power in the D.C. power an auxiliary generator, an exciter, a power take
off unit, the traction alternator being driven by a gear train device,
characterized in that the rectifier is mounted on the traction alternator,
and in that the auxiliary generator, the exciter, and the power take off
unit are mounted on the gear train as substantially described and
illustrated herein with reference to the accompanying drawings.

Documents:

01231-kol-2006 abstract.pdf

01231-kol-2006 claims.pdf

01231-kol-2006 correspondence others.pdf

01231-kol-2006 description(complete).pdf

01231-kol-2006 drawings.pdf

01231-kol-2006 form-1.pdf

01231-kol-2006 form-2.pdf

01231-kol-2006 form-3.pdf

01231-kol-2006 gpa.pdf

1231-KOL-2006-ABSTRACT 1.1.pdf

1231-KOL-2006-CLAIMS.pdf

1231-kol-2006-correspondence.pdf

1231-KOL-2006-DESCRIPTION (COMPLETE) 1.1.pdf

1231-KOL-2006-DRAWINGS 1.1.pdf

1231-KOL-2006-EXAMINATION REPORT REPLY RECIEVED.pdf

1231-kol-2006-examination report.pdf

1231-KOL-2006-FORM 1 1.1.pdf

1231-kol-2006-form 18.pdf

1231-KOL-2006-FORM 2 1.1.pdf

1231-kol-2006-form 2.pdf

1231-kol-2006-form 3.pdf

1231-KOL-2006-FORM-27.pdf

1231-kol-2006-gpa.pdf

1231-kol-2006-granted-abstract.pdf

1231-kol-2006-granted-claims.pdf

1231-kol-2006-granted-description (complete).pdf

1231-kol-2006-granted-drawings.pdf

1231-kol-2006-granted-form 1.pdf

1231-kol-2006-granted-form 2.pdf

1231-kol-2006-granted-specification.pdf

1231-KOL-2006-OTHERS 1.1.pdf

1231-kol-2006-reply to examination report.pdf

abstract-01231-kol-2006.jpg

« Previous Patent

Next Patent »

Patent Number

247744

Indian Patent Application Number

1231/KOL/2006

PG Journal Number

19/2011

Publication Date

13-May-2011

Grant Date

11-May-2011

Date of Filing

16-Nov-2006

Name of Patentee

BHARAT HEAVY ELECTRICALS LIMITED

Applicant Address

REGIONAL OPERATIONS DIVISION (ROD), PLOT NO :9/1, DJBLOCK 3rd FLOOR, KARUNAMOYEE SALT LAKE CITY, KOLKATA 700091, HAVING ITS REGISTERED OFFICE AT BHEL HOUSE, SIRI FORT, NEW DELHI-110049 INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	MANVENDRA BHAKTA	TME DIVISION, BLOCK-9 ANNEXE, 1ST FLOOR, BHARAT HEAVY ELECTRICALS LIMITED, BHOPAL-462022
2	MANISH VERMA	TME DIVISION, BLOCK-9 ANNEXE, 1ST FLOOR, BHARAT HEAVY ELECTRICALS LIMITED, BHOPAL-462022
3	AMBIKA PRASAD SAMAL	TME DIVISION, BLOCK-9 ANNEXE, 1ST FLOOR, BHARAT HEAVY ELECTRICALS LIMITED, BHOPAL-462022

PCT International Classification Number

B61C7/00, F02C6/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA