The electric variable transmission

TLDR

An electromechanical converter with two mechanical ports and one electrical port, comprising two concentric machines and two inverters, functions as a continuously variable transmission that could replace clutch, gearbox, generator, and starter motor in vehicles. The study introduces the electric variable transmission (EVT) as a new converter. The EVT is constructed from two concentric induction machines with a thin yoke, forming a single electromagnetic device whose working principle and losses are explained. The EVT offers similar performance to the original converter while being smaller and lighter, with its losses analyzed.

Abstract

First, an electromechanical converter with two mechanical ports and one electrical port (consisting of two concentric machines and two inverters) is considered. This converter works as a continuously variable transmission between the mechanical ports and may, e.g., replace the clutch, gearbox, generator, and starter motor in a motor vehicle. The working principle of this converter is explained. Next, a new converter, the electric variable transmission (EVT), is presented. This converter has similar properties, but is smaller and lighter. The EVT may be seen as built up from two concentric induction machines with a combined relatively thin yoke. Thus, we obtain one electromagnetic device instead of two magnetically separated devices. The working principle of the EVT is explained, and its losses are discussed