All over the world, people who live in cities and municipalities are suffering from the great strain caused by noise and air pollution emitted by daily traffic. The Schunk Group has decades of experience with electro-mobility and alternative emission-free drives. More than 80 cities in 25 countries world-wide are already benefiting from this. They use durable, flexible and economical pantographs made in Germany for their electric buses. There is now a new pantograph model available – the Depot Charger SLS301. This makes it possible for vehicles of different heights – up to and including double decker buses – to hook up in seconds in the depot.
E-buses with pantographs from Schunk are in use in 25 countries around the world. Whereas only individual buses were equipped for specific projects initially, the company now delivers this key technology for fleets of up to 200 buses. Customers trust in Schunk's experience, which has been gained through more than 100 international projects. The new pantograph builds on the already existing portfolio. The model SLS301 is a Depot Charger. In comparison with “opportunity charging” – charging en route during driving – the advantage of charging in the depot is that it does not require a large amount of current to flow in a very short time as is the case en route. Since charging takes place overnight, the equipment can be constructed simpler, lighter and more compact – making it especially efficient. In addition, it is possible to integrate one or more inverted pantographs into the existing charging structure. In other words, charging en route remains possible.
The Depot Charger SLS301 is an alternative to conventional plug-in solutions which need to be plugged in individually. Instead, the vehicles automatically dock onto the inverted pantograph when parked in the depot for the night. All charging pantographs have precise compensation of parking deviations available during contacting and charging.
Advantages of depot chargers compared with plug-in solutions
Communities or cities that have a fleet of electric vehicles not only have to allow for generously sized parking lots and space between vehicles for the plug-in method due to plugs being attached at the side. Bus drivers also have to be able to park precisely, and at the same time have not been trained to initiate the charging process. In other words, additional personnel needs to be included in costing calculations. In addition, charging equipment solutions involving cables are prone to breakage and wear.
Depot charging with automated pantographs as envisaged by the Schunk solution offers a whole range of advantages in comparison:
- Vehicles can be parked with a certain tolerance under the system. An automatic signal ensures connection to the pantograph. Specially trained personnel is not necessary for the process.
- The charging process takes place via charging rails attached to the roof and docked on from above. Buses can park close together, reducing the parking space required.
- Charging pantographs from Schunk make safe current transmission between the charging infrastructure and vehicle possible. The pantographs SLS102 and SLS103 are mounted on the electric vehicles. This is where contacting with the infrastructure takes place using the bottom-up principle. The inverted pantograph SLS201 is integrated in the charging infrastructure and requires a counter piece on the vehicle for the upside-down connection. The Depot Charger SLS301 is now expanding this portfolio with an efficient overnight charging alternative. Depending on the charging cycles, the systems have a service life of between ten and fifteen years, significantly longer than plug-in solutions.
Successful project in Poland
Various pantograph models supplied by Schunk are currently in use in nine Polish cities, including the capital Warsaw, where 130 vehicles have been equipped accordingly. This is the largest E-bus project in Poland. The new Depot Charger SLS301 is an especially efficient supplement to this system. The southern Polish city of Jaworzno was one of the first customers and has been using the Schunk technology since 2015. The model SLS102 is the one most used here. Its impressive features include its long service life with more than one million charging processes, as well as its high degree of flexibility. Since it can be tilted in all directions, connection to the current source is not interrupted even in extreme positions. This is particularly important when buses “tilt” to one side when they stop to allow easier passenger access. More than 300 vehicles are to be equipped with the pantographs in Poland by the end of 2020. An important driver for e-mobility in Poland is a law introduced by the government promoting the expansion of eco-friendly transport projects. Schunk had made a name for itself as a reliable partner even before it opened its own office in Warsaw in 2018, having often advised cities and communities on long-term projects for innovative mobility solutions before that. Local contacts are now able to benefit from the long years of international experience gained by Schunk’s experts.
Outlook
Electro-mobility in public transport is already a success story which will continue in the next few years. Thanks to Schunk’s know-how, a wide range of individual customer requirements can be taken into account in product development. Schunk’s experts are currently working on getting new systems for underfloor loading ready for market launch so that bus driving will become cleaner and more environmentally friendly all over the world.