Ensuring the optimum performance of a battery management system (BMS) requires measuring the performance of cell, module, and pack voltage, current, and temperature, plus verification of the operational performance of the battery and the cell supervisory circuits (CSCs), which includes static and dynamic accuracy measurements of temperature sensors and Hall-effect sensors at the cell, module, and pack levels. The test setup traditionally requires a known-good set of cells, modules, and packs operating in a controlled environment to test under different environmental conditions. This environment can be hazardous when engineers perform safety tests that bring cells close to their operating limits. In addition, each test requires returning the cells to the known-good condition before the next test can begin.
Testing a BMS efficiently and safely requires emulating cells connected in series and parallel, and emulating their behavior based on temperature and environmental variations. Engineers need a BMS environment with emulators to simulate the cells, current, temperature sensors, and insulation resistance. The system needs to estimate the state of charge (SOC) and state of health (SOH) of the battery and emulate the variables that change during the charging process. Additional interfaces are required to test monitoring systems and communication with other components, such as the electronic control unit (ECU). Closed-loop emulation of the different components enables the verification of all functions, routines, and algorithms to validate BMS functionality, safety, and performance.
BMS testing solution
BMS testing requires emulating a large set of battery cells and varying battery output based on simulated environmental parameters. In addition, the system must emulate the inputs and outputs of the cell supervisory circuits (CSCs), including temperature sensors, Hall-effect sensors, and circuit parameters related to the battery and the contact relays. The Keysight battery management system emulation environment provides all this, eliminating the need for large physical cell sets. It also eliminates the need to control and cycle batteries, returning them to known good states before each test. Its open platform enables deep testing of common and special charging scenarios without limiting flexibility, which enables extensive testing of how a BMS responds to potentially dangerous scenarios.