Tractor equipped with an external electric generator combined with electric powered Sprayer and Mulcher performances evaluation

In the last decades many studies were conducted on tractor and agricultural machinery electrification. In particular, the electrification of traditionally PTO powered implements could apport many benefits such as improved comfort and safety during implement connection, less noisiness, accurate implement rotational speed control and fuel consumption reduction. However, commercially available tractor do not generate sufficient electric power to run electrified implements. One available solution to this issue is to mount on the front Three Point Hitch of the tractor an external electric generator (e-Source) powered by the PTO. The aim of the study is to evaluate the performances of the combination of a tractor equipped with an e- Source and electric powered sprayer and mulcher (e-Sprayer and e-Mulcher) compared with their PTO powered versions (m-Sprayer and m-Mulcher). Field tests were performed acquiring essential parameters such as tractor engine speed and power, travelling speed, fuel consumption, power generated by the e-Source and power absorbed by both mechanical and electrified implements. Moreover, implements noisiness and hitching time were measured. Results show that on the electrified implements the absence of the cardan shaft and hydraulic remotes shortened the implements hitching time and improved comfort and safety during the operation. In addition, the electrified implements were generally less noisy, especially reductions up to 8.3 dBA of the pressure sound level were measured with e-Sprayer. Field tests demonstrated that the adoption of the e-source combined with the electrified implements permitted a fuel consumption reduction of up to 30%. This is mainly due to the independence of the e-Sprayer and e-Mulcher rotational speed from the engine speed of the tractor, allowing the engine to run slower and save fuel.