Increasing the efficiency of an industrial tractor-bulldozer by improving the control algorithm of the motor-transmission unit. Results of mathematical modeling and field tests

The introduction into the design of industrial tractors of continuously variable externally adjustable hydrostatic and electric continuously variable transmissions, as well as internal combustion engines with controlled fuel supply, opens up broad prospects for optimizing the operation of bulldozers and other technological machines based on industrial tractors. Optimization, first of all, in terms of fuel consumption. The materials presented in the article include mathematical modeling of a tractor in the bulldozing technological cycle, formulation of the problem of optimal joint control of the engine and transmission, development of the control algorithm, its implementation in the controller, test conditions and methodology, test results carried out at the plant test site “DST-URAL” in Kalachevo and analysis of the results obtained. As a result, the work carried out by the team of authors recorded a positive effect from the implementation of the developed automatic system, which consisted not only in the expected significant fuel savings, but also in increasing the service life of the internal combustion engine and hydrostatic transmission pumps, and increasing the productivity of the bulldozer, reducing the influence of the human factor (operator qualifications) on tractor performance, increasing operator comfort, reducing cases of activation of the engine overload protection system. Simulation modeling was carried out in the VISSIM programming environment, the code for the controller was created in CoDeSys, testing of the automatic system was implemented on a serial bulldozer tractor produced by the DST-URAL plant D14 with a traction class of 14 tons in August 2023. A patent of the Russian Federation was received for the invention No. 2783552 “Method and device for controlling the motor-transmission unit of an industrial tractor with a continuously variable transmission”. The invention was introduced at the DST-URAL plant.