Design of drive system for series hybrid electric tractor

Abstract: Aimed at the drawbacks of traditional tractors, such as complicated transmissions, inefficient transmission systems, heavy fuel consumption rates, and high exhaust gas emissions, the design method of the tractor's series hybrid electric drive systems was put forward by calculating its plough operation rated traction. A feasible formation was given and included design methods of the electric tractive motor, weight parameters, and prime energy systems, which consist of a diesel engine and a generator of the powerful tractor's hybrid electric drive systems. Transmission ratios of the series hybrid electric tractor drive systems were designed to follow with differences of working load rates under commonly used working conditions, while making sure of the efficiency and capacity of transmission systems. Its storage battery parameters were designed to fill the traction power requirement, which is from the changing load situation when the tractor worked under a light gear. The YTO-1804 wheeled tractor has been taken as the investigative object, its series hybrid electric drive systems have been designed by using the aforementioned method. Upon analysis of its tractive characteristics, the results conveyed that the installed tractor's working adaptability and tractive characteristics are better when it compared with the original tractor. Output of the electric motor is suitable with the requirements of a heavy load working circumstance. The curve portrayed that the relation between the traction force and the traction power of the installed tractor could cover the original tractor's working area. The installed tractor's transmission is more efficient and its structure is simpler. Combined with the relevant slippage test results to analyze the installed tractor's slippage situation, changes in slippage rate followed with changes in driving force are acceptable. Based on the analysis of the difference of equivalent fuel consumption rates between the two types of drive systems, the analysis of the relevant curve, the relevant status of the installed tractor were on the bottom of original tractor's curve. The result proved that the installed tractor has a better fuel economy. Continuously variable function can be reached under a definitional gear. When the tractor is on the working model or the driving model, the most important performance parameter has a wide regulation range. Based on plough operation, furrow plow number and the product of tilling depth value with specific resistance value was seen as an index of the tractor's working load, the result proved that the original tractor's common working area can be distinguished with the relevant gears setting intention, and it has higher efficiency when the load rate is higher. As well, the traction efficiency can be improved 2.98% on average. So, different working requirements of investigative objects can be reached well. The design method laid the foundation for the following study of the powerful tractor's series hybrid electric tractor drive systems.