The BOOST uses an IGBT inverter (INV-I), which is connected to the secondaries of a traction transformer. When energy flows from the DC network during train deceleration, the INV-I recovers it as usual.
During train acceleration, the INV-I injects reactive power into the transformer secondaries, thereby boosting the AC and DC voltage at the rectifier output.
This innovative operating principle offers the following advantages:
- Utilising a robust diode rectifier
- Having complete control over the traction power substations by including an energy recovery system
- Repurposing existing inverter modules designed for energy recovery
- Improved characteristics compared to a thyristor rectifier:
– Enhanced power factor
– Decreased harmonics
– Reduced transformer power