Energy conscious management for smart metro traction power supply system with 4G communication loop

This paper proposes an intelligent traction power supply system for urban rail transits, employing the wireless 4G modules to establish a communication loop among the trains, the ground bidirectional converters and the top-level energy management system. On this basis, an energy-conscious management system is developed, which obtains the instantaneous power and position of each train, parameters of the traction power supply system, real-time status of the substations and bidirectional converters through the 4G based communication loop to realize the digital reconstruction of the real traction power system for facilitating the ensuing optimizations. As physical executors, the bidirectional converters acquire their optimal DC output voltages from the genetic algorithm and then coordinately achieve the power flow dispatching of the entire metro line, so as to make the metro traction power system have a better power supply quantity and a higher efficiency. The full power scale (6.4 Mega-Watt) experiments conducted in actual Ningbo Metro Line 4 verify that the proposed EMS system is effective in energy-saving.