Development of control interface for HIL simulation of electro-hydraulic energy converter

High energy efficiency has become an important topic in the world of off-highway working vehicles because of environmental and economic demands. Hardware-in-the-loop (HIL) simulation is a cost effective and powerful tool to study novel energy efficient power transmission solutions of working vehicles. HIL simulation enables comprehensive testing of novel hardware components and subsystems without the presence of the whole experimental working vehicle. The objective of this article is to develop a control interface for HIL simulation of electro-hydraulic energy converter (IEHEC). IEHEC consists of a hydraulic pump-motor and an integrated electrical permanent magnet synchronous motor-generator. IEHEC is capable to reduce power losses compared to conventional valve controlled fluid power systems. An energy recovery of potential and kinetic energies is also possible using IEHEC. In this article, alternative HIL control interfaces were studied experimentally. The results of HIL simulations were compared to reference results obtained from completely virtual simulations. The results show that a functional and accurate control interface was found. The developed interface will be used in the future to test the suitability of IEHEC for different working machines.