HIL600 simplifies testing and optimization of electric vehicle drive trains
The Institute of Industrial Systems at HES-SO Valais-Wallis is a leading research institution with very strong industry connections. Its cutting-edge innovations serve a dual purpose: they prepare students for the world of work and real-life problems.
In line with other academic partners (HEIG-VD, HEPIA-GE), the Institute of Industrial Systems at HES-SO Valais-Wallis performs applied research activity regarding the integration of a DC bus for micro-grid. This ambitious project is co-funded by The Ark (foundation for innovation in Valais, CH) and by ESR (Energies Sion Région, electrical energy provider, CH).
Under this frame the Institute set itself a goal to develop a VSI (Voltage Source Inverter) which is fed by a DC bus having a mid-point and which can be used in large-scale electric vehicles. The main goal was to make sure that the mid-point required to feed the VSI is perfectly symmetrised. For this purpose, we defined a dedicated voltage balancing cell with active switches.
The HIL600 from Typhoon HIL turned out to be an indispensable tool.. We developed an analog control board with a simple but effective bang-bang controller to balance the neutral point of the converter. The HIL600 was used to test the early design of the control board and then to debug it and fine-tune it. After that, the HIL600 was used again to verify the optimizations in real time, enabling us to considerably shorten the time used to design and optimize the control board, as well as to streamline the whole process.
After HIL testing the control board was ready for the full-scale laboratory tests of the VSI. As expected, the system performed exactly as it did on the HIL600. We even developed a generic comparison tool to compare the results from HIL testing with the results obtained on the real VSI. There are virtually no differences between the results from the high-fidelity HIL600 and from the real VSI.