Theoretical analysis for optimal control of hydrostatic four-wheel drive of a self-propelled harvester

The objective of this article is to examine the hydrostatic four-wheel drive system of self-propelled grain harvesters. The selection of hydraulic pumps is carried out in accordance with the operational parameters of the harvester’s internal combustion engine, ensuring the generation of the required hydraulic fluid flow rate and pressure to meet the demands of the hydraulic motors. The configuration, involving hydraulic pumps with relatively low flow rates and hydraulic motors with comparatively high flow rates, contributes to the efficient and stable performance of the system. Under these operating conditions, overloads are not observed. The pumps driven by the internal combustion engine are typically of variable displacement or variable geometry, while the motors used for driving the running wheels are of fixed geometry or fixed displacement. The selection of pumps and motors is based on the portion of engine power allocated for driving the running gear.