Load balancing in high-speed railway traction power supply systems

The article describes the problems associated with powering high-speed railway traction systems caused by load asymmetry and presents methods and systems for compensating for these asymmetries. The equations presented in the article allow for the determination of the appropriate power value for compensator elements under both normal and emergency power supply conditions.1. HSR POWER SUPPLY SYSTEM AND VOLTAGE ASYMMETRY
High-speed railway traction power supply systems are powered from a three-phase power system via a transformer with a special connection configuration. The primary task of this transformer is to convert the three-phase supply voltage system into a two-phase system. Depending on the transformer’s primary and secondary winding connection configuration used, two sinusoidally varying voltages shifted relative to each other with an RMS value of 25 kV are obtained. Regardless of the primary and secondary winding connection configuration of the supply transformer, voltage and current asymmetry is introduced into the power system [1, 2]. This is due to the fact that the load connected to the two phases of the transformer’s secondary side is asymmetrical, among other reasons, due to the varying number of vehicles powered at any given time from the individual transformer windings. (…)

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