Development and optimization of multi-motor asynchronous electric drives for carding machines

In this paper we describe the main results of the development and optimization of the multi-motor asynchronous electric drive of carding devices. The synchronous rotation of asynchronous motors is developed by the improvement of the “electric working shaft” system with the use of thyristor converters, frequency converters, double-feed machines. In this case, the synchronous rotation of the drive motors is supported by maintaining the power circuit and connecting the rotor circuits to a three-phase resistance. In this article we consider the synchronization of asynchronous motors in the “EWS” system (electric working shaft) facilitating the synchronous start-up of the engines of the carding machines and their synchronous braking, excluding the preliminary synchronization, as well as synchronous start-up. The equations of the moments of a multi-motor asynchronous electric drive of coordinated rotation for the unbalanced feeding of their motors, consisting of the moments of the engines with forward and reverse directions of rotation of the magnetic field are given. In subsequent developments with MAED microprocessor control, asynchronous motors with a phase rotor are used instead of asynchronous motors with a short-circuited rotor, and synchronous rotation of the drive motors is solved by using frequency converters controlled from industrial microcontrollers. For further optimization of the electric drive of the carding machine, the principles of the double-feed machines were applied. In this case, the MAED carding device is controlled from the rotor side by frequency converters with and without maintaining the power connection of the rotor circuits. At the same time, the necessary power of frequency converters for controlling the electric drive of the carding machines is reduced by 2-2.5 times.