Reviewing and Comparing Different Algorithms and Topologies to Control the Speed of Multi Electric Train Motors by a Drive System

With the growing trend of electrification in the rail transportation industry, the control system of electric motors plays a crucial role. Typically, each metro train consists of multiple wagons, and each wagon is equipped with several electric motors. In the conventional transportation system, each electric motor of the train is powered by a three-phase inverter, which increases the cost of the drive system and requires more space. Alternatively, another method involves using a three-phase inverter to control multiple electric motors, but this approach cannot independently control each motor. This paper provides a comprehensive review along with a comparative analysis of single-input multiple-output inverter topologies, along with some suggestions for selecting suitable configurations for electric transportation applications, particularly electric railways, to achieve independent control of each electric motor. Modern railway systems utilize multiple electric motors/drives for various functions such as traction, braking, steering, and suspension. As the number of electric motors in a train increases, challenges and issues arise in terms of cost, space, reliability, control, and energy management. This paper presents various architectures for power inverters to reduce the number of components and achieve centralized control in train bogies, different methods of motor synchronization in multi-motor drive systems, control algorithms for single-motor drive systems, and their extensions to various multi-motor drive structures.