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The new fleet of electric, high-capacity and high-frequency metros will transform Brisbane’s bus network by unlocking capacity to help get more people to where they want to go, at the times they want to travel.
The metro fleet will use Hitachi Energy’s high-tech Grid-eMotion® infrastructure to charge the metros at end of route locations. The high-performance charging system is the first of its kind in Australia and will play a key role in supporting the turn-up-and-go Brisbane Metro services.
The charging strategy for Brisbane Metro, utilises Grid-eMotion® equipment, striking a balance between battery size and life, infrastructure requirements and operational efficiency.
There will be two types of Grid-eMotion charging technologies used to charge a fleet of 60 metros: Flash charging and CCS2 plug-in chargers.
The flash charging system will be capable of recharging the metros in up to six and a half minutes at the end of route locations by using overhead pantograph infrastructure that autonomously connects the charging point to charging equipment on the roof of the metro.
CCS2 plug-in chargers will be used at the metro depot to support battery conditioning and increase the battery lifespan. The project also includes e-mesh™ EMS and a Power Load Management system to control the charging and optimise the current drawn from the grid to moderate peak loads.
The 60 new metros, manufactured by HESS, will provide a comfortable, sustainable and energy efficient solution that will integrate seamlessly into busway operations as part of a better planned network.
Maintaining service frequency and optimising fleet requirements
The Grid-eMotion® charging solution is centered around delivering turn-up-and-go metro services. Charging will occur at the end of route locations and has been optimised to meet charging requirements. The batteries and charging power have been carefully selected to ensure that each metro can travel between end or route locations with sufficient battery state of charge, even during peak times.
An additional benefit of the flash charging is it allows for a greater passenger capacity on board the metros. By flash charging the metros at end of route locations, rather than carrying large batteries on-board, more seating can be allocated to passengers.
Matching battery chemistry to the task
The Grid-eMotion® Flash charging system powering the metro fleet relies on lithium-titanium-oxide (LTO) battery chemistry to support frequent high-power charging. These batteries have a unique chemistry that is perfectly suited to the metro application, where charging takes place at end of route locations throughout the day instead of relying on a single charge to last the entire day.
Charging integrated in vehicle operation
To provide frequent and reliable services, flash charging starts within seconds of arriving at a charge point. Hitachi Energy’s roof-mounted pantograph, Energy Transfer System (ETS) uses an active alignment system to ensure when the metro door-brake is activated the pantograph connects to the feeding station and charging commences.
The metro fleet uses feeding stations instead of chargers. The Grid-eMotion® Flash charging system relies upon the power electronics mounted onboard the metro, which are used to power the motor and wheels. The same components that support regenerative braking to charge the battery during driving are used by the Flash system, which is connected directly to the power grid via the ETS and feeding stations. Like regenerative braking, charging at a terminal station happens instantly.
Keeping drivers focused on driving not on battery levels or charging
Hitachi Energy’s Grid-eMotion® Flash system and ETS pantograph function automatically, allowing drivers to keep their focus on passenger safety and metro operation.
Battery charging is automatic during the metro on-route operation. Upon arrival at an end of route location, the pantograph automatically raises and aligns to an overhead rail for charging, without any driver intervention.
Due to the need for high power, the system is connected directly to the medium voltage electricity grid and charged at 600 kW - allowing the metro to continue its journey quickly. The benefit of the LTO chemistry means there is no damage to the batteries over time.
A system connected to a low voltage electricity supply would have higher losses due to the inherently higher currents required. At the metro depot, the Grid-eMotion® Fleet system will support 60 metros, with an independent 50 kW charger for each vehicle overnight and during extended parking periods. The metros will be connected at low power using a CCS2 plug to ensure the batteries stay conditioned and the metro is heated or cooled depending on the season for passenger comfort before departure.
Metro depot chargers are centralised in one location and coupled directly to the medium voltage grid, with a redundant connection to avoid outages. To help maximise space, the system has been designed to be compact.
For more information on Grid-eMotion® visit: Grid-eMotion | Hitachi Energy
The latest news on the Brisbane Metro project can be found at: Brisbane Metro | Brisbane City Council
About Hitachi Energy
Hitachi Energy is a global technology leader that is advancing a sustainable energy future for all. We serve customers in the utility, industry and infrastructure sectors with innovative solutions and services across the value chain. Together with customers and partners, we pioneer technologies and enable the digital transformation required to accelerate the energy transition towards a carbon-neutral future. We are advancing the world’s energy system to become more sustainable, flexible and secure whilst balancing social, environmental and economic value. Hitachi Energy has a proven track record and unparalleled installed base in more than 140 countries. Headquartered in Switzerland, we employ around 40,000 people in 90 countries and generate business volumes of approximately $10 billion USD.
About Hitachi, Ltd.
Hitachi drives Social Innovation Business, creating a sustainable society with data and technology. We will solve customers' and society's challenges with Lumada solutions leveraging IT, OT (Operational Technology) and products, under the business structure of Digital Systems & Services, Green Energy & Mobility, Connective Industries and Automotive Systems. Driven by green, digital, and innovation, we aim for growth through collaboration with our customers. The company’s consolidated revenues for fiscal year 2021 (ended March 31, 2022) totaled 10,264.6 billion yen ($84,136 million USD), with 853 consolidated subsidiaries and approximately 370,000 employees worldwide. For more information on Hitachi, please visit the company's website at https://www.hitachi.com.