Design, Specification and Installation of a Resistive Load Bank for a Hybrid-Electric Propulsion Test Bench

Abstract

The present work describes the design process, building and testing of an electronically-controlled resistive load bank for being used in a lab environment. The bank's basic characteristics are from a preliminary design on a previous work. The bank is part of an aircraft hybrid-electric propulsion test bench for stationary analysis, aiming to be low-cost and safe to handle. It is intended to simulate the variable mechanical load that an aircraft propeller applies to the drivetrain axis, at different rotation speeds on steady state conditions. Supplied by an electrical generator (EG), it can apply its resistive load in steps, which gets converted into a mechanical load by the generator. The support frame that houses the resistive elements and cooling fans was designed, built and assembled. Two sensor boards were developed to measure voltages and currents. The bank's controller is implemented with an Arduino board, employs a real-time operating system (RTOS) and communicates with a supervisory system hosted on a computer through a Controller Area Network (CAN) bus. The program's user interface was created as a Windows Forms App to allow ease of use and real-time monitoring of the bank's operation. A single load tap was built and tests were performed on it to validate sensor performance and acquire thermal response curves. Results indicate the system operates predictably and reliably, encouraging further developments.