Multilevel frequency converters for differential electric drives

Reliable operation of industrial automotive equipment is one of the most important requirements, especially in the conditions of the far north. The most difficult task is starting the internal combustion engine, which is complicated by the low ambient temperature. The paper proposes the use of a differential electric drive as a starter-generator. It combines the starter and generator into a single electric machine and increases the energy efficiency of the unit. By using a planetary gearbox, we achieved a 10:1 change in the torque and speed in the generator and engine modes. Stable operation of the starter-generator in the starting mode was achieved by using a multi-level frequency converter and a synchronous reluctance motor with an independent excitation channel. This differential drive reduces the weight and size of the underhood space, increases the probability of starting the internal combustion engine, and consequently reduces fuel consumption.