High-order sliding mode control of DC-DC converter for PEM fuel cell applications

The power converters play a key role for the performance of fuel cell power system. The fuel cell output voltage and power depend highly on the random load profile. Thus, a robust design and analysis of the converter can help the online control and optimize the diagnostic method in fuel cell applications. In this paper, a robust control algorithm for DC-DC converter for proton membrane fuel cell (PEMFC) applications is realized through a high-order super-twisting shding mode method (STSM). The effectiveness of the proposed control methods is verified on a buck-boost converter under various operating conditions including step and varies input disturbances. Moreover, the proposed high-order sliding mode control algorithm can avoid the chattering phenomenon, which commonly happens in power converters when conventional sliding mode control method is deployed. The simulation and experimental results indicate that a stronger robustness can be obtained through the STSM method. The simple architecture of the proposed STSM make it easily to be implemented for the real-time online diagnostic control.