Research progress and development trend of electric agricultural equipments

Green agriculture needs energy saving and emission reduction agricultural machinery, and it is feasible to replace fossil energy with new energy based on electricity to become the power source of agricultural machinery. Agricultural machinery is a kind of non-road mobile machinery working in farmland, which is a complex and changeable unstructured scene, including paddy field, hilly farmland and facility farmland. Agricultural machinery for the operation of the object that is the crop is also a lot, the operation of the link also contains a plowing and planting management and harvesting and other operational aspects, which makes the agricultural machinery operation load changes, to the design of electric agricultural machinery has brought many technical difficulties, coupled with the rural areas of the maintenance capacity of the poor, small farmers poor affordability and other socio-economic factors, resulting in the popularization of the application of electric agricultural machinery there are many problems that need to be solved. The characteristics of new energy agricultural machinery using pure electric, hybrid, solar auxiliary power and fuel cell power were reviewed. Domestic and foreign large-scale agricultural machinery manufacturers have begun to actively layout the field of new energy agricultural equipment, but mainly concentrated in the concept machine stage. Endurance is a key factor restricting the development of electric agricultural equipment. The battery life of pure electric agricultural machinery products mainly relies on the increase of battery energy density, and hybrid agricultural machinery products increase the battery life through fuel, solar energy or clean fuel. Electric agricultural equipment products are currently mainly concentrated in the concept machine stage, the real mass production of products is less, in addition to consumer product cognition issues, economy is the main determining factor. Compared with foreign countries, China's electric vehicles and new energy industry chain is complete, the rapid development of electric construction machinery, to provide favorable conditions for the electrification of agricultural equipment, should make full use of advantages, accelerate the development and promotion of electric agricultural equipment. This paper starts with the operation characteristics of agricultural machinery, analyzes the key technical requirements of electric agricultural machinery on battery components, electric drive components, electric drive control, energy management and collaborative control, discusses the technical methods to increase the battery life of electric agricultural machinery, adapt to low speed and high torque and multi-power output conditions, and summarizes the relevant technical research progress. It is suggested that the battery life of agricultural machinery can be increased by increasing the battery energy density, increasing the battery charging efficiency and increasing the auxiliary power supply. In terms of electric drive, agricultural machinery operations require low-speed motors with large torque, and the different speed requirements of transfer fields and operations require electric drive systems with large speed ranges. In terms of control, the whole machine energy algorithm and coordinated control of agricultural machinery is the focus of research, compared with electric vehicles, electric agricultural machinery in addition to providing power to the driving parts, but also need to achieve the power output of each working part, so the multi-power output power dynamic regulation algorithm is one of the focuses of research. The application of electric agricultural machinery in facility planting, hilly and mountainous areas and leisure agriculture was forecast. In view of the existing problems, it is pointed out that in the future, research should be carried out in the aspects of high-pass special chassis, high-adaptation three-power system, electrification transformation of operating parts, intelligent electrification technology integration, etc., to improve the comprehensive performance of electric agricultural machinery, reduce the cost of electric agricultural machinery through agricultural machinery subsidies, agricultural machinery multi-functional, “battery bank” construction and other methods, and improve the promotion speed of electric agricultural machinery.