3. Continuous catenary input converter

In Europe, the three main sources of continuous power supply are :

• 750 V (RATP, England...) ;

• 1,500 V (SNCF, Hollande...) ;

• 3,000 V (Belgium, Spain, Italy...).

The input converter for traction units powered by continuous catenary is a "current chopper", or simply "chopper". Depending on the configuration of the chopper, energy is transferred from the supply line to the motor, or vice versa.