Why LHB Coaches in Indian Railways Need a Generator Car Despite Not All Coaches Being AC
Taken from a modern perspective, the LHB (Linke Hofmann Busch) coaches in Indian Railways are designed to enhance passenger comfort and operational efficiency. This article delves into the rationale behind including a generator car even when not all coaches are air-conditioned.
Purpose of the Generator Car
A generator car serves as a critical component in ensuring that all coaches in the LHB rake can function efficiently and provide a good level of service to passengers. Its inclusion is driven by a combination of power supply needs, standardization, future flexibility, operational efficiency, and enhanced passenger experience.
Power Supply for Amenities
Even non-AC coaches require power for amenities such as lighting, fans, and charging points. A generator car ensures a reliable power supply to all coaches, enhancing the overall journey experience.
Standardization
Standardizing the inclusion of a generator car across all coaches simplifies maintenance and operational procedures, making fleet management more efficient.
Future Flexibility
The generator car infrastructure allows for the future upgrade of non-AC coaches to AC without needing to redesign the entire power supply system, providing greater flexibility for Indian Railways.
Operational Efficiency and Passenger Experience
The generator car supports the entire rake, providing power to all coaches during remote journeys where external power sources may be unavailable. This ensures that all passengers have access to the necessary amenities, enhancing their experience.
Structural Analysis of Bogies and Coaches
Understanding the distinction between bogies and coaches is crucial. A bogie is the undercarriage with wheels, while a coach is the mounted structure that carries passengers. Different types of bogies are used in Indian Railways, each with unique features and capabilities.
ICF Coaches and LHB Coaches
ICF (Indian Coach Factory) coaches use either 13-ton or 16-ton bogies, while LHB coaches use FIAT bogies with better safety features. LHB hybrid coaches maintain the ICF bogie structure for enhanced safety and speed.
Alternator Arrangement in Bogies
In ICF coaches, alternators can be easily attached in the under-slung area of the bogie. This allows for power generation and distribution, optimizing the power supply for non-AC coaches. AC coaches use 2×25kW alternators, while non-AC coaches have a single 4.5kW alternator.
Visual Representation
The alternators in LHB coaches, which use FIAT bogies, cannot be attached in the same way as ICF coaches. Thus, they rely on end-on generation (EOG) to supply power to the coaches.
Head On Generation (HOG) Technology
To address the issues caused by the introduction of EOG coaches, Indian Railways introduced the HOG technology. In this system, power is supplied from the train locomotive to the coaches, bypassing the need for a generator car in the trailing coaches.
Hotel Power System
The HOG system involves a 25kV transformer in the electric locomotive, which converts three-phase AC to 750V. This power is then distributed to the coaches, both AC and non-AC. Currently, only the WAP-7 locomotive is capable of HOG, with limited capability in WAP-5 and yet-to-be-realized capability in diesel locomotives.
Observation of HOG Implementation
As of recent observations, many LHB trains have been seen with one EOG coach, supported by the hotel power system of the locomotive, rather than a generator car in each coach.
Visual Aid
A YouTube video of a recent run of the Paschim Express shows this new configuration. The train carries one LHB Luggage Car, one EOG coach, and ends with a Second Class cum Brake/Guard Van, featuring only one EOG coach per train.