For the HIL test for battery management systems (BMS), high-voltage batteries have to be simulated at cell level. To make this possible dSPACE provides the high-precision EV1077 battery cell voltage emulation board.
Emulation Electronics Setup
Cell voltage emulation is performed with several EV1077s. The number of these controllable buffer amplifier boards is configured to match the battery type. The boards supply an adjustable voltage in the range 0 to 6 volt. This relatively wide range means that damaged cells can be emulated. For example, a short-circuited cell can be emulated by outputting 0 V, and a voltage higher than the nominal voltage simulates a cell's increased internal resistance during charging.
The voltage is output with a precision of ±1.5 mV across the entire working temperature range. The voltage is galvanically isolated, allowing the modules to be connected in series up to a voltage of 800 V. A reference value step is corrected completely in less than 500 µs. Fast data transmission means that a change to all the cell's voltages takes less than 1 ms.
The maximum current that can be supplied or sunk is 1 A, which is sufficient for the usual balancing currents. For special requirements, up to four modules can be connected in parallel to quadruple the maximum current. dSPACE's Automotive Simulation Models are ideal battery simulation models.