High-tech drive systems for rail vehicles: Part 1

Development of a completely new, speed-controlled drive system for the railway

Milan Central Station: It's 4 p.m. and on platform number 1 one of Europe's fastest trains, the Frecciarossa1000, is already waiting for the conductor's start signal. I want to go to Rome. After 3 hours and 10 minutes of travel, passengers will get off in Rome, Termini Station. They used to spend at least 6 hours on the 477 km long route.

The Italians are very proud of their “Red Arrow”, as the Frecciarossa1000 is also called. The design is similar to that of an Italian sports car manufacturer. Just like this one, it is high-tech first class - very modern from the outside and the interior is of the highest standard. When I see this train, I also feel a little proud.

I work at VEM. My company produces electric motors, also for the railway industry. VEM worked with partners to develop a drive that cools the high-tech train's traction motor. When the Frecciarossa1000 sets off from the train station, the engine can be very warm. Added to this is the high current when starting. It is important that the train's traction motor is sufficiently cooled. The highest performance is required from the cooling system.

If the Freccierossa1000 is traveling on a high-speed route at 300 km/h, the traction motors work under full load. The highest thermal loads occur. The highest performance is required from the cooling system. In addition, special requirements and approvals apply to electrical assemblies manufactured for the railway sector.

Is VEM the right partner for the project?

The solution - a newly developed compact drive for railway applications

Our designers looked for partners with whom they could implement the goal of a drive with railway approval and the required parameters, consisting of a motor with a converter. In addition, passengers should have more space in the new high-speed train. Therefore, solutions were sought to reduce the size of the control cabinets and install the frequency converters in a different location.

The solution was a motor with an attached frequency converter. Until now, there was no compact drive for railway applications. With the German companyA.S.T. Power electronicsVEM had found the right partner for the new development. They developed the new frequency converter. Before it was ready for series production, many customer requirements still had to be met, such as the higher voltage strength of the output relays to 160 VDC or their dual-coded output function. A special winding was needed in order to be able to take the nominal torque even at 55 Hertz. We delivered the first drives with milled heat sinks for the new frequency converter. Once the heat sinks had proven themselves, we designed our own housing for them.

The detailed test phase of the compact drives could begin

Now the first prototype of the ventilation system could finally be tested. Extensive thermal and electrical tests were carried out. We then manufactured a sample series of 16 compact drives and delivered them to the client Systemair . A high-speed train requires 16 compact drives. The Berlin company installed our new development on the ventilation unit. Compliance with railway standards, including shock and vibration loads, was tested. The functional tests of the compact drives took two months at elevated temperatures and humidity. After the ventilation system had passed all tests, it was ready for installation in the Frecciarossa1000.

I'm still standing on the platform, the train attendant asks all passengers to get on. I get in and my journey begins. Would you like to find out more about our new drive and the Frecciarossa1000? Then read part 2, which will appear soon.