Battery electric drive of excavator designed with support of computer modeling and simulation

The motivation for this article was an effort to create an battery electric drive of a smaller excavator of a well-known manufacturer. This research followed the solution of the kinetic energy recovery of the road roller. The aim of the excavator electrification research was to replace its internal combustion engine with an electric motor so that the innovated excavator does not burden its surroundings with gas emissions and excessive sound emissions, so that it can work in confined spaces or protected areas. The solution was carried out in a number of stages– a patent search, the structure, functions, variants of individual solutions were analyzed, the technical possibilities of individual subsystems and the whole proposed electric drive system and the entire excavator with its mechanical and hydraulic systems were analyzed. The resulting variant included an accumulator, a Bodas RC control system, an electric motor control, a frequency converter, a special electric motor, etc. 3D models of drive elements were created to deal with the installation. Simulation models of electrical and hydraulic parts of the drive were created to select the most suitable solutions, which were verified or predicted by simulations in Matlab/Simulink environment. Tests have shown that the excavator is capable of operating for at least 7 hours without recharging the battery. The knowledge gained within the project will help in the electrification of other constructions, earthmoving and other machines, specifically the wheel loader, etc. In the development of the new electric battery drive of the excavator, mathematical modeling and simulations have proved to be a valuable tool. The main achieved results of the project are a functional model of a zero-emission mini-excavator with significantly reduced noise, a proven control algorithm in the form of software and its utility model according to the application 2018-35127 adopted by the Industrial Property Office of the Czech Republic. Innovation of the solution of the excavator was awarded the Gold Medal at the International Engineering Fair in Brno in 2018.