An Analysis of Field Weakening Mode in DTC Based Induction Drive for Control Influences Forming

The article deals with DTC-based induction drives. DTC systems provide the same regulated properties as AC electric drives like DC electric drives. To expand the speed-range ratio in a DTC-based induction motor and provide a motor work with speed above its synchronous speed, it is necessary to weaken the induction-motor field. At the same time, DTC-based induction-motor work in the field weakening zone requires improvement. Therefore, the task of control-strategy synthesis in the field weakening zone of the DTC-based induction motor is very important. To ensure satisfactory dynamic and static characteristics of DTC-based induction drive in the zone of flux weakening, it is advisable to change the flux linkage in inverse proportion to the change in speed. The field-weakening mode in DTC-based induction motor in order to determine a control influence in case of two-zone speed regulation is analyzed.