Energy Efficiency of Agricultural Tractors Equipped With Continuously Variable and Full Powershift Transmission Systems

Abstract

The efficiency of agricultural tractor transmission has been improved over the years, with new concepts such as Continuously Variable Transmission (CVT) and Full Powershift (FPS) evolving in advanced technologies. Both options seek to offer the farmer greater operational results with lower energy expenditure, necessitating studies to assess the effectiveness of these technologies and define the best choice for each purpose. The objective of this work was to evaluate the energy efficiency of two tractors equipped with CVT and FPS transmissions. For this, a strip experiment was conducted in a randomized block design, that analyzed, in addition to CVT and FPS transmissions, target velocities of 4, 6, 8 and 10 km h -1 . Operational energy performance parameters were evaluated, such as slippage index, engine rotation, operational velocity, fuel consumption, power available and efficiency on the drawbar, turbo pressure and temperatures of air intake and exhaust gas. Based on the results obtained, the tractor with FPS transmission was more energy efficient in most of the analyzed parameters, requiring 16.31% less in hourly fuel consumption, and providing 16.29% more in the traction bar yield, however, with lower operational velocity compared to the tractor with CVT transmission.

Full-Powershift Energy Behavior Tractor in Soil Tillage Operation

“…Analyzing the effect of speed on YD (Figure 2A) an increase of 2.07% is observed with the increase of 1 km h -1 , added to the 0.63% resulting from displacement speed and the relation between tractor weight and power. This can be explained by the fact that this parameter varies depending on the magnitude of the torque that the engine-transmission set is capable of applying to the drive wheels, according Strapasson Neto et al (2022).…”

“…Presently, different transmission types are provided by the national and international markets, especially the Full-Powershift transmission model (Strapasson Neto et al, 2022). This transmission operates by adjusting the gears and engine rotation through an electronic manager, coupling gears in an electro-hydraulic mode, with a limited number of gears (Li et al, 2019;Siddique et al, 2023).…”

Theoretical Calculations and Experimental Studies of Power Loss in Dual-Clutch Transmission of Agricultural Tractors

“…Additionally, research considering power loss in transmissions has also been conducted in the agricultural tractor sector. The efficiency and energy consumption of tractor transmissions have been examined primarily in relation to operating conditions using vehicle tests [23,24]. Studies have also been conducted to predict transmission efficiency by examining the power loss generated by each component of agricultural DCTs through theoretical calculations [25].…”