Novel topology and control of single inverter system for two permanent magnet synchronous machines

This paper proposes a novel topology which is capable of operate two permanent-magnet synchronous machines (PMSM) using a single 6-bridge inverter and its control method. In the conventional parallel connection method for this application, two motors can operate only at the same speed and have a high risk of loss of synchronism since the single voltage is applied to both motors. In other inverter topologies, the number of switches increases or implementation of inverter is complicated. On the other hand, the proposed topology can employ the conventional six bridge power module without any modification or addition and operate two motors at the different speeds using the superposition principle. The analysis of the proposed system is presented and the control method to independently operate two motors is proposed. It is verified through experimental results.