基于微分平坦理论的燃料电池用高增益DC-DC变换器鲁棒控制研究

As an important energy generating device in distributed information energy system, fuel cell plays an important role in the security of energy network. However, due to the low output voltage of fuel cell and the large range of fluctuation with the loads, it is necessary to use a high-gain DC-DC converter to realize a safe and stable DC-bus for the safe operation of loads. In this paper, an output series Boost converter was studied. In order to improve the power converter's ability to reject internal and external disturbances, the outer voltage loop and inner current loop were designed by using the theory of differential flatness control. In addition, the disturbance observer was used to estimate the parasitic parameters of the system, so as to improve the ability of the system to reject the perturbation of internal parameters. At the same time, the load current and input voltage are estimated in real time to reduce the number of sensors, therefore the system cost can be also reduced. Finally, to verify the effectiveness of the proposed control scheme, a 240W converter prototype was built to obtain some necessary experimental results.