In order to overcome the random and intermittent of photovoltaic(PV)power generation
realize the high reliability and quality of power supply
a hierarchical control method based on photovoltaic/storage battery/super capacitor/fuel cell(FC)DC generation system is proposed. For the multi-parameter and non-linear characteristic of hybrid DC power supply system
the control of upper layer designs differential flatness method to compensate non-linear components directly
which realizes the non-linear dynamic reversibility of system
makes the DC bus voltage still stable under situations of great changes of PV output
loads and system parameters. Meanwhile
the upper layer provides reference track for total load current to lower layer. Aiming at different characteristics of multiple power sources in the hybrid DC power supply system
the control of lower layer utilizes model prediction method to design weighting factors to extend cycle life of the system. According to the conditions of photovoltaic output and load demand
the charging and discharging rate of storage unit is dynamically adjusted
which makes the system immediately track the current expectation of total loads to achieve the reasonable distribution of power in various sources. Based on the MATLAB/Simulink
the simulation results show the feasibility and effectiveness of proposed method