The Electric Choremaster: Development and Performance of an Agricultural Electric Tractor
Abstract
The National Rural Electric Cooperative Association partially funded a project at South Dakota State University for development of an electric tractor in 1983. The goals of this project were to build, demonstrate and evaluate a battery-powered farmstead chore tractor which would lead to a commercially produced and widely accepted vehicle. Three major results were expected from the work: 1) test results and analyses to verify the feasibility of farmstead electric vehicles and to indicate some of the problems and limitations encountered during actual use, 2) a vehicle to demonstrate the concept of e1ectric vehicles to farmers and to farm equipment manufacturers, and 3) design information for an electric vehicle prototype which could be used to aid the commercial development of electric farm vehicles. Design of this tractor, the Electric Choremaster, was a team endeavor. As a member of the design group, this · author's responsibilities were to: contribute to the vehicle design criteria; review and evaluate power train components; size, select, and supervise the installation of motors and drive train components; and perform the first ·phase of testing and evaluating the completed prototype. This thesis reports on the development of the Electric Choremaster and can serve as a guide for future developments of agricultural electric vehicles. Specific objectives of the research reported in this thesis were to: 1) describe the design process used for development of the Electric Choremaster, 2) detail the power train design for the Electric Choremaster, 3) evaluate the performance of the Electric Choremaster as compared to a conventional diesel tractor, and 4) investigate the effects of battery temperature and state of battery charge on vehicle performance.