Usable time estimation and suitable battery selection for electric tractor considering agricultural operational load

Area of Science:

• Agricultural Engineering
• Electrical Engineering
• Sustainable Energy Systems

Background:

• Electric tractors offer a sustainable alternative to traditional agricultural machinery.
• Accurate battery selection is crucial for ensuring the operational viability of electric tractors for extended periods.

Purpose of the Study:

• To estimate battery usable time and discharge rates for a single-motor electric tractor.
• To select an appropriate battery capacity for full-day (8-hour) agricultural operations.
• To validate dynamometer test results with field rotary tillage data.

Main Methods:

• Conducted dynamometer tests under light, medium, and heavy-duty loads.
• Performed field tests using rotary tillage at L-slow, L-fast, and M-slow gear stages.
• Validated power consumption and usable time estimations between dynamometer and field tests.

Main Results:

• Dynamometer tests showed power consumption of 6.25 kW, 8.76 kW, and 14.51 kW for different loads, yielding usable times of 3.00 h, 2.33 h, and 1.25 h.
• Rotary tillage tests confirmed similar battery consumption trends, validating the dynamometer-based estimations.
• A 900 Ah (64.8 kWh) battery was identified as suitable for 8-hour operations at the L-fast gear stage for rotary tillage, considering practical weight and space limitations.

Conclusions:

• The study provides a feasible method for selecting electric tractor batteries for real-world agricultural scenarios.
• A 64.8 kWh battery capacity is deemed suitable for full-day electric tractor operations, balancing energy needs with physical constraints.
• Further research could incorporate traction efficiency and slip ratio for more refined gear stage selection.