Starting transients in slip energy recovery induction motor drives. I. Formulation and modeling

The authors examine the starting transients of slip-energy recovery induction motor (IM) drives when started directly with the rotor rectifier. The starting transients of slip energy recovery IM drives comprising three stages are presented: starting from zero speed with a starting resistor connected to the output of the rectifier; the transmission period in which the inverter is connected through a DC link; and the final period when the starting resistor is disconnected from the rectifier output. A hybrid model is used which retains the actual rotor phase variables but transforms those of the stator only, to examine the starting transients of a slip energy recovery drive system