Design load analysis for electrification of a 55-kW agricultural tractor based on workload

Abstract

Abstract This study aimed to determine and analyze the design loads required for the electrification of a 55‑kW agricultural tractor through field experiments. A measurement system was installed to record data from the engine, driving axles, power take‑off (PTO), and hydraulic pump during plow tillage, rotary tillage, and driving operation in a silt loam paddy field. The study specifically focused on power requirement analysis, load duration distribution (LDD), and rainflow counting (RFC)–based load spectrum generation for durability assessment of the electric tractor powertrain. Plow tillage imposed the highest loads, with total power peaking at 52.6 kW (95% of rated power) dominated by axle torque, while rotary tillage was PTO‑driven and driving operation showed low average loads with intermittent traction peaks. Compared with a previously studied 78‑kW tractor, the 55‑kW tractor exhibited lower overall power requirement and a more traction‑balanced distribution, while hydraulic requirements remained minimal. LDD and RFC analyses revealed that a few load cases and low‑amplitude cycles dominate the operating profile, and critical high‑load cycles occur primarily during tillage. These findings provide essential design data for electric powertrain components and establish a systematic measurement‑to‑spectrum methodology for deriving design loads for agricultural machinery, supporting the future development of utility electric tractors and durability‑driven powertrain design.