Closed loop control of fuel cell with a buck converter
This video explains the control algorithm for the fuel cell. The output power of the fuel cell is controlled by a D.C. converter, and the output ports of the converter are to supply power for the electric load. One way to prolong service life is to have the fuel cell system deliver steady-state power. However, because of fluctuations in the bus voltage and uncertainness in the D.C. converter, the output power of the fuel cell system changes drastically. A closed-loop control algorithm is necessary to eliminate the errors between the output and target power of the fuel cell system. The algorithm is composed of two parts, the feed-forward one and the feedback one. Influences of the bus voltage and D.C. efficiency are compensated automatically in the feedback algorithm by using a PI algorithm. The stability and robustness of the algorithm are analyzed. Formulas for choosing suitable parameters are given considering both the transient process and the system stability. Experimental results show that the stable relative error between the target power and the actual output power of the fuel cell system converges to zero.