An Open-End Winding Machine Modulation Technique for Balancing Power Switches' Temperature

Open-end winding machines (OEWMs) present several advantages compared with traditional motors for many applications. Typically, they are supplied on both sides by two three-phase two-level inverters. Different modulation techniques have been proposed to optimize the operation of the drive composed of an OEWM and two inverters. In this paper, the most common modulation techniques are compared in terms of efficiency and balanced load on the inverters' components. It is shown that the most efficient modulation techniques are not the ones balancing the load on the switching components. Moreover, a new modulation technique is proposed to decrease the number of switching events on one of the inverters while providing a good heat balance in the inverters. The proposed modulation technique is compared with the others by means of numerical simulations in a Matlab/Simulink environment, showing a very high efficiency while keeping well-balanced the load on the switching components.