Frequency-Current Induction AC Electric Drive with Vector Correction of the Control Signal

The problems of creating controlled electric drive systems based on an induction motor with a phase rotor, easy to manufacture, cheap to maintain and economical, remain relevant due to their fairly wide application on lifting and transport mechanisms (LTM), for example, on bridge metallurgical cranes and conveyors. At the same time, one of the important tasks is to increase the efficiency of AC electric drives with energy saving, which is achieved through the introduction of a frequency converter. At the same time, the parametric start-up control and frequency control systems currently used, made on the basis of starting resistors and controllers, are not economical in terms of energy consumption and do not allow to provide the required dynamic indicators. Currently, frequency converters with a DC link implemented on fully controlled IGBT transistors are mainly used to power regulated AC electric drives. The development of control systems for AC electric motors has led to the emergence of new algorithms for controlling the power switches of the frequency converter, which improve the quality of the voltage feeding the stator winding, reduce the number of high-frequency harmonics in the generated voltage and current of the stator. A promising direction for the development of frequency asynchronous electric drive systems based on an asynchronous motor with a phase rotor, characterized by the ability to measure the instantaneous values of the phase currents of the rotor, is the use of scalar frequency-current control systems with additional correction circuits of moment-forming variables, allowing to implement scalar control with vector correction of the three-phase signal setting the instantaneous values of phase currents of the stator.