A Brief History of Railway Electrification in India
by Anirban Das Gupta, Sep. 2010, revised Dec. 2012
Part II
Continued from Part I.
Electric locomotives for AC Electrification Programme
The pioneer broad gauge type electric locomotives for our AC electrification system, were imported from 1958-59 onwards, from a very famous European consortium called the 50 Cycles Group (also, known as the 50 Hz Group, 50 Hz Project Group, 50 Cycles European Group or simply the Group, consisting of Alsthom, Schneider-Westinghouse / Jeumont, MTE, Siemens, AEG, Brown-Boveri, Maschinenfabrik Oerlikon, ACEC and some others). These electric locomotives were provided with Ignitron tube rectifiers initially, and featured Bo-Bo axle pattern. Classification was BBM 1, and this was later altered to WAM-1 by IR, after certain technical modifications, like equipping the locomotives with more reliable Excitron tube rectifiers, and fitting of knuckle couplers with adaptors at the ends (CBCs). In short, these engines heralded rectifier technology, on IR.
The initial stud of WAG 1, goods duty electric locomotives also came from the 50 Cycles Group, around 1960-61, and these engines featured B-B axle pattern,and not Bo-Bo. Each bogie had a single traction motor, so the bogies are referred to as "monomotor" bogies, a typically French practice. This design was taken up by the Indian Railways, as the first AC locomotive design, to be made here in India.
The next set of electric engines arrived in 1960-62, from Japan. A consortium called the Japanese Group (consisting of Hitachi, Toshiba and Mitsubishi), built and supplied WAM-2 class electric locomotives of Bo-Bo type. These units featured Ignitron tube rectifiers. The same consortium, supplied WAG 2 type monomotor design, goods duty electric locomotives. Around 1962, the 50 Hz Group supplied ten WAG-3 class electric locomotives for freight work, and these heralded silicon-rectifier technology on IR, along with three WAM-3 class Bo-Bo electrics supplied by the Japanese Group. Silicon rectifier technology is still used in India.
For metre-gauge, AC electrification was completed by 1966, and in 1965, deliveries started for monomotor type (B-B) electric engines of YAM-1 class, from the Japanese Group. Today none are in service, but once upon a time, these were quite unique in India and equally powerful for passenger and goods trains on SR's metre-gauge lines. Rectifier type EMU rakes started being supplied by ICF to SR for metre-gauge routes.
Back to broad gauge-the first rectifier type electric locomotive built in India was one of WAG-1 class, and this was No. 20710, christened "Bidhan" which was inaugurated in 1963. It was quite an advanced product in the early 60s and it was manufactured by CLW after a successful transfer of technology by the 50 Cycles Group. This engine is preserve at the NRM, New Delhi. CLW progressed further with silicon rectifier technology, by assembling and manufacturing WAG-4 class goods duty electric locomotives from 1965. These featured monomotor bogies.
More advanced technology and designs on broad gauge
This is the final saga in this narrative about electric locomotives of India. 1960s saw a big locomotive movement in terms of adoption of the latest and the best electric locomotive technology for IR, as well as intense research and hard work, which eventually bore fruit, from the early 1970s. In 1971, for 25 kV AC routes, CLW outshopped Co-Co type rectifier locomotives of WAM-4 class. Similarly, for Mumbai's DC routes powerful freight locomotives of WCG-2 class were rolled out. WAM-4 and some WCG-2 engines are still hard at work, in 2012, but for the DC locos their days are numbered. WCG-2 class locomotives were supplied to CR. Considering Mumbai's DC routes, especially the WR main line section from Bombay Central to Ahmedabad via Virar, CLW built and supplied the dual current electric locomotives of class WCAM-1 from 1974. The first one was named "Vallabh". It featured Co-Co axle pattern. Bharat Heavy Electricals Limited or BHEL started supplying certain electric locomotive components to CLW, and these were used in WAM-4 and WCAM 1 locomotives. WAM-4 class became a test bed for more powerful and advanced designs, like the dedicated goods duty electric engines of WAG-5 class and sleek passenger duty electric engines of WAP-1 class. There had been numerous sub-classes for WAM-4 and WAG-5 electric engines. The WAG-5 and WAP- 1 were made by CLW from 1980. In 1987, under licence, BHEL produced some WAG-5HB class locomotives. In fact, WAG-5HA and WAG-5HB classes were fitted with Hitachi-made traction motors.
The K.K.Line on the Eastern Ghats, was a part of South-Eastern Railway (SER).The route is a very arduous one in terms of the inclines and curves and 25 kV AC electrification was completed on this mountain line in the 1980s. Initially, WAM-4 class electric engines were used by SER, geared fro heavy goods trains, followed by WAG-5 class locos, and based on a requirement to offer more powerful engines on this route, eighteen thyristor type electric locomotives were imported by IR, from 1987. There were actually three sub classes WAG-6A, built and supplied by ASEA of Sweden (ASEA became a part of the ABB Group in 1988), WAG-6B and WAG-6C classes built,and supplied by Hitachi of Japan. These locomotives, till 1995-96, were the most powerful, in India and certain concept like their Bo-Bo-Bo bogies (WAG-6A and WAG-6B classes only) were not popular here. (WAG-6C class locomotives are of Co-Co type, and feature high-adhesion bogie design, by Hitachi, also supplied to some DC electric engines of Morocco in Africa. This bogie design was subsequently adopted by CLW and BHEL for future locomotive classes) Some of these heavy duty locomotives are still at work on the K.K.Line today. By the time thyristor technology was being researched, it was observed that 3-phase AC motor technology is gradually being preferred where the concept for 25 kV AC was essentially a mono-triphase concept. Single-phase AC was modified and subsequently altered to produce 3-phase AC to feed the 3-phase AC motors of the electric locomotives and EMU rakes.
CLW, on behalf of Indian Railways, in 1993, signed a transfer of technology arrangement with ABB Transportation (subsequently ADtranz, and presently, Bombardier Transportation) for manufacturing of state-of-the-art electric locomotives with 3-phase drive system. By 1996, seventeen completely built, 3-phase AC electric locomotives arrived in India: the WAG-9 class with Co-Co axle pattern, was the freight design, while the eleven passenger locomotives were awarded the WAP-5 class nomenclature. These have Bo-Bo axle pattern. This order was a part of an order for a total fleet of thirty-three 3-phase electric locomotives (22 for goods, 11 for passenger). Sixteen WAG-9 class electric locomotives arrived in kit form, assembled on site at CLW.
Silicon rectifier technology for electric engines was ultimately manifested in powerful goods duty electric engines of WAG-7 class, made initially by CLW since 1992, and as of today, some have been built by BHEL with a streamlined exterior, and air-conditioning. On the passenger front CLW started manufacturing rectifier type electric engines of WAP-4 class in 1994, followed by some of WAP-6 class. These locos are the ultimate manifestation of silicon rectifier technology on IR.
In 1995-96, BHEL, made and supplied powerful dual current (25kV AC/ 1500 volts DC) electric locomotives to WR. These are of WCAM-2 class, with a Co-Co axle pattern. The bogie design was somewhat similar to WCAM-1 and WAM-4 classes, but the difference is that, the bogies are fabricated. In 1997, BHEL supplied WCAM-3 class dual current electric locomotives to CR, for the Mumbai Region, which was still on DC. These locomotives feature Hitachi design traction motors and high adhesion bogies. BHEL also supplied some freight duty, dual current electric engines of WCAG-1 class. All of these locomotives are still working today.
In November 1998, the first 3-phase AC electric loco of WAG-9 class, to be made in India, rolled out of CLW. It was aptly named "Navyug" meaning new era and by the turn of the century and the beginning of the new millennium CLW was able to gift us with two WAP-5 class electric locomotives ("Navodit" and "Navjagran"). A heavy duty passenger electric locomotive design was developed by IR, in consultation with RDSO and ADtranz, of WAP-7 class, and the prototype was named "Navkiran". It was made in India by CLW for tests. Today, CLW is producing top class 3-phase AC type electric engines and we are proud to have always received the best technology which had been successfully aligned with the requirements we have for railway operations in India.
In 2000-01, when it was announced by IR that, on WR, the Virar-Dahanu Road Sector would also be absorbed in to the Churchgate-Virar section as an extension of WR's Mumbai Suburban Operations, some existing DC only EMU rakes, were modified with 3-phase AC motors and dual current equipment, supplied by Alstom Transport, France. The modification took place at the famous Mahalakshmi Workshops of WR in Mumbai. WR today uses 25 kV AC, all throughout Mumbai area. CR is gradually changing to AC.