In view of the slow response characteristic of large power proton exchange membrane fuel cell（PEMFC）and its inherent V-I relationship，a grid-connected topology including the150kW PEMFC（HD6）system，the DC/DC converter and inverter is built，and a novel SQ control method suitable for this topology is proposed.By introducing the reference control signals of a large power level PEMFC system，the DC and AC sides of the total micro-power system can be effectively coupled.This method is not only able to quickly track the grid power demand，but also prevent the instability in conventional PQ control because of the relatively slow response of PEMFC power source.The above problems and their solutions are analyzed and verified by simulation.Simulation results show that under the voltage stabilizing effect of the DC/DC converter，this topology can reduce the impact of the DC bus voltage fluctuation on the inverter，improve the system sensitivity to DC bus voltage and the safety and stability of the large power PEMFC.