Tsenta E. An improvement of working process hydraulic unit of the tractor mounting equipment by the synthesis of correcting devices

Object of research is the interaction processes of working liquid with the executive bodies of hydraulic unit of the mounting equipment. Purpose of research is the improvement of the dynamic characteristics quality of hydraulic unit of the tractor mounting equipment on the basis of developed mathematical model and synthesis of corrective devices. Basic research methods are: system analysis, methods of machines and mechanisms theory, methods of liquid and gas mechanics, methods of mathematical modelling, methods of the optimal systems theory. Theoretical and practical results are: the software in the form of diagrams of computing blocks of a VisSim package; procedure of the correcting device (PID-regulator) synthesis with non-linear dependences of control channels; procedure of correcting device synthesis allowing to improve working process of hydraulic unit; modular principle of hydraulic unit mathematical model with variable structure; algorithm of input into the mathematical model of hydraulic unit in a VisSim package of experimental and model curves. Scientific novelty is: for the first time the advanced mathematical model of working process of hydraulic unit of the mounting equipment was developed and it takes into account the inter-element connections, non-linearity of hydraulic devices characteristics, wave processes in pipelines, two-phasing and compressibility of working fluid, changing of discharge coefficient in throttle apertures of elements, changing of load, friction in the valve couples, reverse negative connections, and allowing to perform a wide complex of researches of hydraulic unit dynamics and to improve its static and dynamic characteristics; for the first time the dynamic synthesis of correcting device by the integral criterion was carried out and it provides an essential reduction of speed fluctuation of motion of hydraulic cylinders rods (mounting equipment) and decrease of pressure pulsation of working fluid in various devices of hydraulic unit; for the first time the correcting device synthesis was carried out, the adjusting channels non-linear characteristics of which realize the small set movements and working out of small mismatching signals by the position of the mounting equipment and traction effort. Degree of implementation: chair of hydraulic machines of NTU "KhPI", LRC "Promgidroprivod" (Kharkov). Scope - mechanical engineering.