Full steam ahead for ‘green’ trains

This article originally appeared in the March'23 magazine issue of Electronic Specifier Design – see ES's Magazine Archives for more featured publications.

There has been much discussion about the rail industry moving away from its dependence on such fossil fuels as oil and gas and attempts to graduate towards genuinely ‘green’ transportation offerings.

Having environment-friendly trains is more than merely switching power sources. It is important to be able to measure and evaluate energy consumption with better granularity for transparent energy billing and to forecast, adjust, and optimise electricity production and consumption.

Energy metering

One solution to being able to manage energy consumption in railway applications is to adopt the use of on-board train energy metering, which involves combining energy measurement system (EMS) with ground-based data collection systems (DCS). Together, these systems give railway operating companies the ability to manage energy costs for individual trains by having access to precise and controlled measurements under the European regulation (EU) 2018/868.

Such systems also need to be capable of operating within challenging environments, including extremely low and high temperatures, while being able to satisfy every railway standard that covers such aspects as vibration, fire protection, shock, and electromagnetic compatibility (EMC).

One of the latest products developed by LEM is a the TEMA4G on-board energy meter. The device enables timestamped and localised energy billing data to be measured and transmitted to ground based DCS, with precise energy measurement (class 0.5 R) made possible by TEMA4G's ADCs. In compliance with the EN 50463:2017 standard, the TEMA4G is designed for use in multi-system AC or DC environments and in a wide range of temperatures from –40°C to +85°C. The monitor has long-term stability in various operating conditions, reports LEM.

Meter design

The TEMA4G meter’s architecture is designed to enable rapid retrofit implementation. It also allows it to be incorporated into new designs where easy connectivity is crucial. This means the meter is able to meet the requirements of railway operating companies involved in creating new projects as well as large retrofit programmes and which want to have a better grasp of energy monitoring and management.

A key feature of TEMA4G is that it processes measurement signals from current and voltage sensors then generates energy measurement and associated load profiles. These are recorded in datasets with five minute intervals (other timings can be selected). It can also include information such as time, date, location co-ordinates, and any events that may have happened. These measured energy datasets are stored for 300 days in the LEM device in consumption profiles.

The TEMA4G combines the company’s EM4TII+ on-board energy meter which is already used in many trains with an industrial modem offering 4G and GPS connectivity. TEMA4G has been designed to simplify the transition towards 4G networks and its web interface which allows users to access detailed load profiles, as well as numerous system parameters.

On-board communication

The company says it has built sufficient versatility into TEMA4G for it be suitable for use with any kind of trains and projects. This includes features specifically for the particular requirements of railway applications including four input channels offering multiple configurations via the Ethernet port as well as data exchange security.

Greater energy management and optimisation are essential in the modern rail transport sector, and it is vital that solutions are developed to meet the need to improve the efficiency of electrical systems. LEM has used its experience in on-board sensors for trains and complex systems using embedded software to develop TEMA4G to meet the very latest challenges the railway sector is facing in terms of energy management.

On-board energy metering is the future for today’s rail operators.