18 March 2021
Siemens Mobility using Infineon’s 1200V CoolSiC MOSFETs for trains
Siemens Mobility GmbH (a separately managed company of Siemens AG) and Infineon Technologies AG, both of Munich, Germany, have jointly developed new auxiliary converters that use silicon carbide (SiC)-based power semiconductors to improve the efficiency of on-board power systems in trains.
The auxiliary converter makes use of power semiconductors (in a half-bridge topology) that are based on Infineon’s CoolSiC MOSFET 1200V technology. Depending on the design, between 8 and 16 half-bridge modules are installed for each converter.
“Our vehicles should not only offer the highest level of passenger comfort but also enable our customers to operate them sustainably over the entire product life-cycle,” says Albrecht Neumann, CEO of Rolling Stock at Siemens Mobility. “Energy-efficient on-board train power systems can make a major contribution to economical and environmentally friendly train operations.”
Siemens Mobility uses the new converter for various train platforms, which are hence said to be maintenance-friendly, reliable, economical and power efficient. “With SiC, we achieve higher switching speed as well as efficiency to reduce the size of transformers, capacitors, cooling elements and the housing unit,” says Dr Peter Wawer, president of Infineon’s Industrial Power Control Division. “The advantages of this semiconductor material are evident and are now being leveraged in rail-bound vehicles,” he adds.
In addition to providing the AC voltage (e.g. 3 AC 400V 50Hz) required for the vehicle power system, auxiliary converters also deliver the required battery voltage (e.g. 110V DC). To achieve this, they convert the DC voltage provided at the converter input. They ensure that train passengers can charge laptops and smartphones; the air conditioning and ventilation systems are running; and the on-board restaurant can offer hot and cold drinks and food. Without them, connectivity, information or entertainment services on trains would not be available. As part of the system, SiC reduces the overall costs in the on-board electrical system and the energy consumption of the auxiliary converter. It also enables more compact and lighter converter designs, along with a modular and service-friendly design to ensure lower maintenance costs, the firms say.