Optimization of the magnetic system of a VR machine for traction electric drives in agriculture

Abstract

The purpose of this article is to optimize a VR machine for traction electric drives in agriculture, as well as to identify its advantages and disadvantages, to compare an electric drive based on a test machine with an asynchronous electric drive of the same size. The optimal ratio of the elements of the magnetic system of the electromechanical converter based on the VR machine. It is shown that the overload capacity of an electric drive with a VR machine is about 25%. The specific electromagnetic moment of the studied machine is 30% higher than the corresponding indicator of an asynchronous machine of the same size in the nominal operating mode. The disadvantage of this machine is its low power factor, only 7%. This is due to the small ratio of conductivities along the longitudinal and transverse axes of the machine due to the large number of stator and rotor teeth. The problem is solved by introducing additional DC or AC windings on the stator. It is shown that a change in the air gap significantly affects the specific moment. Only by reducing by 2 times the air gap managed to increase the moment by 48%.