The market for signalling, train control and telecommunication systems in India has expanded significantly in the past few years. Till 2006, there were only two operational metro projects – Delhi metro, Phase I, and Kolkata metro. However, with the operationalisation of metro systems in a number of cities, the market for advanced signalling and telecommunication (S&T) systems has grown substantially. The Ministry of Housing and Urban Affairs has made it mandatory for metro corporations/contractors to procure nine types of signalling equipment from domestic manufacturers. The move is aimed at incentivising the setting up of manufacturing facilities in the country and making India a manufacturing hub. Also, to promote healthy competition in the S&T segment, the ministry has standardised norms for the procurement of S&T equipment.
Key features and advantages
Signalling systems are used to direct traffic, keep trains at a safe distance from each other, and ensure that they run as per schedule. The systems ensure that train operations are safe and smooth by separating trains, ensuring they have enough braking distance to stop, and also by routing trains down the correct tracks and platforms. The systems bring down staff costs through driverless operations and improve quality of service, which enhances reliability and ensures shorter waiting time at platforms. State-of-the-art telecommunication systems facilitate continuous communication between central controllers, train operators and station controllers. These are modular, reliable and proven systems. They make certain that all station communication equipment operates independently in “local mode” in the event of a failure in the link between the operations control centre (OCC) and the station. Besides, telecommunication systems facilitate broadcast and display of train-related information in different languages and provide emergency call point phones at stations to assist passengers in case any help is required.
System upgrades and innovations
The nature of signalling, train control and telecommunication systems has evolved over time. While the Kolkata metro ran on absolute signalling systems, the Delhi metro became the first to deploy continuous automatic train control (ATC) signalling systems. After ATC came, communication-based train control (CBTC) next. It is the highest grade of automation (GOA4) and is designed to provide immediate status updates and control to prevent accidents in the event of special circumstances such as sudden breakdowns and power loss. CBTC, because of its mobile nature of application, uses wireless local area networks. The advanced CBTC, RF-CBTC, enables continuous two-way digital communication between each train and the OCC. The control system benefits from enhanced information such as train performance data and continuous train position and speed. Systems of this type, therefore, have dynamic distance control, thus making the block locations and lengths consistent. The latest technologies in metro rail networks include driverless train operation and unattended train operation (UTO) using CBTC signalling with moving block technology instead of fixed block technology.
Recent developments
With the objective of enhancing the reliability of S&T systems across various metro rail projects, a number of measures have been taken. These include progressive upgradation of signalling systems by deploying electronic interlocking with centralised operation of points and signals, multicoloured LED signals, complete track-circuiting of stations, digital-axle counters and automatic signalling.
The Delhi Metro Rail Corporation (DMRC) is planning to upgrade its signalling system and introduce the concept of “virtual signals” on the Blue Line, and subsequently on the Red Line and Yellow Line as well. The new signalling system is expected to reduce train delays by up to 80 per cent. It will also ensure that metro trains reach the nearest interchange system at a faster speed. Besides, virtual signalling will keep metro trains operating at the normal speed of 35-37 km per hour during the deployment phase. The system is expected to be in place by end 2021. The virtual signal system can be utilised, wherever needed, in order to divide the route between any two fixed signals. To provide a boost to the Make in India initiative, the DMRC is planning to develop its own signalling system, for Phase IV corridors, in collaboration with the Centre for Development of Advanced Commuting and Bharat Electronics Limited. In March 2019, Alstom won contracts to supply CBTC signalling systems and modern telecommunication systems to Lines 2A, 2B and 7 of the Mumbai metro and Corridors I and II of the Pune metro. The company is also providing a signalling system with UTO technology for the Mumbai metro’s Line 3. The telecommunication contract includes public address systems, passenger information display systems, fibre optic transmission systems, CCTV and access control systems.
Conclusion
The upcoming metro, light rail and MetroNeo projects are expected to create huge opportunities for players in the S&T segment. With the government’s focus on automation of operations, there has been a surge in the demand for modern S&T systems. These systems are economical, reliable and efficient. Besides, in view of the ongoing pandemic, the technology has come to the fore to ensure that physcial distancing norms are complied with. These systems are expected to play a crucial role in ensuring smooth operation of metros, with a minimal requirement of personnel, and help avoid crowding at metro stations.