A Novel VSI and CSI Fed Active-Reactive Induction Motor Drive with Sinusoidal Voltages and Currents


Abstract— Till date Load Commutated Inverter (LCI) fed synchronous motor drive configuration is popular in high power
applications(>10 MW). The leading power factor operation of synchronous motor by excitation control offers this simple and rugged
drive structure. On the contrary, LCI fed induction motor drive is absent as it always draws lagging power factor current. Therefore
complicated commutation circuit is required to switch off thyristors for a current source inverter (CSI) driven induction motor. It
poses the major hindrance to scale up the power rating of CSI fed induction motor drive. A new power topology for LCI fed induction
motor drive for Medium Voltage drive application is proposed. A new induction machine (Active Reactive Induction Machine) with
two sets of three-phase winding is introduced as a drive motor. The proposed power configuration ensures sinusoidal voltage and
current at the motor terminals. The total drive power is shared among a thyristor based LCI, an IGBT based 2-level VSI and a 3-level
VSI. The benefits of SCRs and IGBTs are explored in the proposed drive.
Experimental results from a prototype drive verify the basic concepts of the drive.
Index Terms— LCI, CSI, Medium Voltage Drive, Active Reactive Induction Machine, VSI, Induction machine, synchronous machine.