Volker Peinecke

Online stack monitoring tool for dynamically and stationary operated fuel cell systems

The motivation for this development of a new fuel cell stack monitoring system is to establish a much simpler, low-cost stack diagnosis unit feasible for large production volumes. In comparison to conventional cell voltage monitoring (CVM) technology, where up to several hundreds of voltage channels have to be measured, Total Harmonic Distortion Analysis (AVL THDA) significantly reduces the required wiring, contacting and instrumentation. This new approach derives information about critical cell and stack status from only the stack sum voltage. A real-time output signal then indicates whether the stack – in fact every single cell – is operating under safe and reliable conditions. The new technique also detects critical stack operating conditions during load changes, where other monitoring systems usually have difficulty in distinguishing between a change in the voltage of a single cell as a result of load changes or resulting from the occurrence of a critical cell operating status.