A Converter-Based Starting Method of a Direct power control for a Doubly Fed Induction Machine with Centrifugal Loads

Now a day’s adjustable speed drives has grasped more attractive usage for applications like pump, compressor, and other centrifugal load applications rather than conventional constant speed drives due to their high efficiency and flexibility of operation. In general to start up a Doubly Fed Induction Machine (DFIM) an additional starting resistors or an auto transformer is needed. In this paper a converter-based starting method for a DFIM with centrifugal loads by constant volts/hertz control is proposed, instead of using the additional starting resistors or autotransformer. It is also discussed a grid synchronization control scheme for motor starting and a Direct power control scheme for the operation of machine in high-speed region. Hence it is stated that the above said machine is operated in the whole speed region effectively by combining constant volts/hertz control and direct power control. Finally the proposed control technique is simulated in MATLAB/ Simulink environment and the results are produced. Keywords—Direct Power Control (DPC), V/F control, Grid synchronization, DFIM, Centrifugal loads.