Dual scalar controlled drives of induction motors using single voltage source inverter for long cable applications

This paper presents dual scalar controlled drives of induction motors using single voltage source inverter through long feeding cables. As known, when the cable length is long, over-voltages at motor terminal could be doubled from the pulsed output voltage at inverter terminal. In this paper, a half DC-link inverter is implemented to drive two motors simultaneously for different configurations of cable lengths. The implemented inverter drastically reduces the over-voltage at both motor terminals with a proper duration time of V_dc/2 level (beta). Simulation and experimental results are provided to show the effectiveness of over-voltage reduction by using this inverter. According to these results, for two motors with different cable lengths, this beta should be calculated based on the cable length closed to the longer one.