EXPERIMENTAL STUDY OF LINEAR ELECTRIC DRIVE OF THE DOUBLE-BREED CUTTING MACHINE OF THE GRAIN COMBINE HEADER

Abstract

The article is devoted to the development and research in the work of an experimental installation of an electric drive of a two-blade cutting apparatus of a combine harvester harvester. The layout of the combine harvester elements is given, the cutting apparatus of which is supplied with electric drive based on two-sided flat linear asynchronous motors. The kinematic diagram of the linear electric drive of the cutting apparatus was compiled, its efficiency was evaluated in laboratory conditions. It was revealed that for efficient operation of the cutting apparatus, the operation of drive induction motors in the mode of forced oscillations is preferable. This eliminates the position sensors and it is possible to adjust the parameters of the oscillations of the knife strips according to the technological process of cutting. A study was also made of the linear electric drive of the cutting apparatus of the combine harvester in field conditions. For this purpose, a thyristor switching and control unit for linear asynchronous electric motors, designed and tested under laboratory conditions, which allows optimally adjusting the parameters of the oscillating process of knife strips for specific harvesting conditions, was connected to a mobile diesel generator set. In this case, the time dependences of the currents of inductors of two-sided flat linear asynchronous motors and the amplitude of oscillations of the blade strips of the cutting apparatus were experimentally obtained. When comparing the current consumed by inductors of linear motors by the maximum amplitude and pulse duration, it was concluded that when the linear electric drive of the cutting unit operates in a steady state, the current difference is no more than 8,8 % compared to the previously obtained theoretical data. The combination of the experimental time dependence of the oscillation amplitude of the knife strips of the cutting apparatus with the theoretical one allows us to conclude that the difference in the amplitude of oscillations does not go beyond 8,4 %. All this testifies to the adequacy of the previously obtained mathematical model.