Electric drive of coordinated rotation for mechanisms of flow-transport systems

Abstract The frequency method is currently recognized as the most technically and economically feasible approach for controlling alternating current electric drives. However, systems employing frequency-controlled electromechanical setups with stator circuits, while offering extensive capabilities, present a more intricate challenge for voltage frequency regulation compared to systems utilizing rotor circuits. This complexity arises from the fact that the power of a thyristor frequency converter is comparable to that of electric motors. Consequently, there is a pressing need in contemporary electromechanics for the development of innovative circuit solutions to regulate the performance of flow transport systems. This study aims to design a two-motor electric drive for the mechanisms of flow transport systems with medium to high power, aiming for improved energy efficiency. As a result of this study, it was found that utilizing a cascade circuit in a dual-motor electric drive, along with an additional power source in the rectified rotor current circuit, enables the synchronized rotation of two motors. This synchronization can be achieved not only with identical nominal parameters but also with differing power and synchronous frequency of rotation. The primary advantages of this coordinated rotation approach in a twin-motor electric drive using a cascade scheme include the ability to adjust the power factor of the machines and reduce the power transferred to the control circuit by the thyristor frequency converter, thereby enhancing the reliability of the electric drive’s power components. Furthermore, by regulating the rotation frequency of two AC motors, it becomes feasible to enhance overall energy efficiency.