Q) Where we got the locomotive technology from?
Ans):-Transfer of
technology (ToT) from ABB (Switzerland, Germany & Australia). Then ToT partners developed in India with an aim to indigenize the major equipments.
Indian Railway obtained Technology from ABB, for indigenous
manufacturing of two types of 3Ф electric locomotives viz. WAG9 freight and WAP5 passenger class
through ToT agreement signed in 1993. Based on the know how, the new variants WAP-7 and WAG9H class locomotives were produced. Serial
production of WAP-7 was taken up from 2000 and that of WAG-9H from 2011.
Indigenization of 05 major equipment viz. Traction Motor, Transformer, Traction
Converter, Auxiliary Converter and Central Electronics along with other items
of the loco has been done.
Q)Why are IGBT based Converters used for in Locomotives?
Ans) 3-phase locomotives in Indian
Railways are equipped with GTO based converters. GTO based converters have
disadvantages such as poor Slip/slide control due to group drive, higher switching
losses, complex snubber circuit and above all obsolescence of GTO. Therefore, IGBT (Insulated Gate Bipolar Transistor) based
converter is being used.
First locomotive with IGBT based Traction Converter
was rolled out in December 2009 and first locomotive with IGBT based Auxiliary
Converter was rolled out in October 2010. For FY 2012-13, about 40 locomotives
with different mix of converters are expected to be rolled out with IGBT based
converters. As per Railway Board’s directives 70% of 3-ф locomotives with IGBT
based converters have been targeted to
be rolled out in FY 2013-14.
Q) What is Open Platform Control System for Vehicle Control with TCN
compatibility?
Ans):Present vehicle control system of 3-phase
locomotive is based on ABB proprietary protocol MICAS-S2, which is of 1980s vintage.
Thus, the system is vendor specific and has disadvantages such as difficulties
in modification/upgradation due to specific compatibility of available hardware
with software. Further, being an old system hardware architecture is based on
old slow processors and components.
Open control VCU works on published
protocol based on IEC-61375, also known as TCN (Train Communication Network).
Application Software coding is based on PLC languages complying IEC-61131. Due to use of high speed processors, there
are less number of processor cards, faster signal processing and implementation
of latest algorithm for signal processing. No special tool is required for
downloading the software in locomotive and troubleshooting.
Indigenous development of TCN compatible vehicle control system has been tried. First
locomotive with indigenous TCN compliant vehicle control system has been
dispatched to ELS/TKD in December 2012.
Q) What is the status of Indigenous development of IGBT based
3- Phase propulsion equipment?
Ans):CLW has placed supply orders on M/s Medha Servo Drives Pvt. Ltd.
for indigenous development of the 3-Phase propulsion equipment. The prototype
supply is expected by May 2013.
Q) What is Hotel load Converter?
Ans):Diesel power cars used in Rajdhani/Shatabdi
trains consume ever depleting fossil fuel accompanied by emission of air and
sound pollution.
Hotel load converter utilizes
pollution free and cheaper power from OHE. It has highest reliability as
compared to SG and EOG system due to reduced number of generating equipments. Cost saving per loco per year on account of
fuel only is estimated to be Rs. 50 Lakhs and thus return on investment can be
achieved in less than three years.
First locomotive with Hotel load
converter is running under commercial service in Kalka Shatabdi since February
2011.
Q) What is Active Speed sensor with Doppler radar on 3- phase locos:
Ans):The 3-ф loco is a group drive system. Slip (Slide) control algorithm
is based on comparison of the bogie wise filtered lowest(highest) axle speed
with the highest (lowest) axle speed in traction (braking) mode. In case of
wheel slip/slide in a bogie this algorithm doesn’t give correct reference
speed. The problem is particularly severe in case of slipping/sliding of all
axles in a bogie.
Speed sensor with Doppler radar has been developed for 3-phase
locomotives. In this system, actual ground speed is measured by radar which is
taken as the reference speed. The loco slip/slide is detected with respect to
the ground reference speed. This will result in better slip/slide control.
05 prototype units of Speed sensor with Doppler radar Speed sensor
with Doppler radar have been installed in locomotives and trials have been
conducted under ELS/GMO.
Q) What is wireless remote control of slave locomotives In a long haul train:
This system, popularly known as
Locotrol, has been developed to handle heavier and longer trains with
locomotives distributed over the length of the train. The Master locomotive
(one which has the loco pilot) controls other locomotives through the RF wireless
link in distributed power (DP) consists. This enables optimized distribution of
traction and braking action, faster acceleration and deceleration leading to
improved throughput and faster cycle times, reduced crew need and increased
overall tonnage hauling capabilities.
The first pair of 3-phase WAG-9 locomotives
with RRCS (Radio Remote Control System) is running in commercial service under
ELS/Tata. CLW has also developed wireless MU coupler system for microprocessor
based AC tap changer locomotive. The first pair of locomotives with this system
is running under ELS/KZJ.
Q) What is Hurth Coupling (Alternate Drive Gear Assembly for WAP5) ?
Ans) :There were reliability issues of the presently used Hurth coupling by way of improved
design of the transmission system. Hurth
coupling has a rubber membrane where as Alternate Drive Gear system has
combined curved tooth coupling/ring disc
coupling, having no rubber membrane. First locomotive with alternate
drive gear system for 160 kmph service speed has been dispatched to
ELS/Vadodara in Decemder 2012.
First locomotive with alternate drive gear system for 160 kmph
service speed.
Q)Can we operate WAP-5 in multiple consists?
Ans): Yes !This enables running of
24 coach trains at a speed of 160 kmph. WAP-5 Multi Locomotive enables operation
of slave loco, without raising its pantograph, taking OHE power from master
locomotive through HV cable.
Successful trial with modified loco
software has been carried out under NR. WAP-5 loco Nos. 30059 & 30060 with
MU system has been dispatched to ELS/BRC in February 2013.
Q)Can we operate WAP-5 in multiple consists?
Ans): Other developments are:
- Composite Converter: There are space constraints in WAP-5 locomotive for installation of hotel load converter. As the IGBT based traction converters have smaller size vis-à-vis GTO converters, CLW has planned to develop the composite converter housing both IGBT traction and hotel load converter in the same cubicle for WAP-5 locomotives. The hotel load inverter shall be fed through common DC link.
•
Development of drive gear system to
increase the speed potential of WAP-5 up to 200 kmph is in its advanced stage
and is likely to be installed by September’13.
•
Development of common software across
all the variants of locomotives.
Q) What are ACHIEVEMENTS OF CLW IN RECENT YEARS?
•
Turning out first Electric loco with
IGBT based Traction Converter in December 2009.
•
Turning out first Electric locomotive
with IGBT based complete Propulsion system in July 2012.
•
Turning out first locomotive with Hotel
Load Converter in June 2010.
•
Turning out first Electric loco with
Open Control VCU in October 2010.
•
Turning out first 3-Phase Loco with
Locotrol system in January 2011.
•
Turning out first Microprocessor
based conventional locomotive Locotrol system in July 2012.
•
Turning out first locomotive with
indigenous VCU in December 2012.
•
Turning out first WAP-5 locomotive
with advanced alternate gear drive system in December 2012.
•
Installation of prototype Doppler
radar based slip/slide control system for improvement of slip/slide performance
of 3-Phase locomotive in December 2012.
•
Porting of existing MICAS-S2 based
loco software into IEC 61131 compliant Functional Block Diagram based PLC
Language for TCN compliant VCU.
•
Completion of 3-D modeling of 3-Phase
locomotives.
•
Development of Improved 10.4” Color
Driver Display Unit.
•
Development of Remote Diagnostic
System.
•
Development of Active speed sensor.
•
Indigenous Development of GUL ASIC
for Gate drive unit of traction converter.
