Central component of a BCS
The core of a BMS hardware-in-the-loop (HiL) system is the cell voltage emulation, with increasing requirements regarding accuracy, error simulation, value ranges, etc.. For a long time, these points alone have been insufficient to meet the high demands of OEMs and Tier1. A BMS-HiL should therefore emulate the temperature sensors in order to test the algorithms for winter conditions but also safety mechanisms, in case of overheating of cells.

Additional testing and simulation options
Since the battery must not be connected to PE (protective earth), there are additional requirements for insulation monitoring, a safety-critical element, which must be reliably tested under a wide range of climatic conditions. In addition, other environmental conditions have to be simulated by other control units, be it through analogue or digital signals or a residual bus simulation.

No valid result without verification
All in all, it is important that the test system also offers verification options and taps in order to make tests, accuracies and results verifiable. This also includes a very good self-diagnosis of the test system in order to be able to mark a test case as “not valid” in case of an error. All tests must be carried out in real time and be fully automated, reproducible and safe. This also includes a safely locked test item and an automatic shut down in case of an attempted access by the test person while testing.

Systems tailored to every requirement
Meeting the demands of car manufacturers and suppliers is always the incentive for comemso. An example of such a customer-specific test stand, with its unique combination of modules, can be seen in the illustrations. The most striking feature is the so-called Breakout-Box with the coloured banana sockets. With the help of these, the customer can pick up any signal separately in order to validate the data of the BCS.

Unusual requirements such as these are comemso’s speciality, for which a very high in-house production depth has been built up with its own electronics production, software development, laser cutting and engraving machines. From the individual transistor to the simulation software – everything from a single source and "100% Invented in Germany".