In order to reduce the adverse effects of the distributed generation system to the main grid, a reasonable and effective solution is a systematic method, that is, microgrid. And the bus voltage of the micro grid will fluctuate when the main grid got failure or the micro grid is disconnected to the main grid. The paper proposed using super-capacitors energy storage system as part of the micro grid's electrical energy storage to retrain the normal voltage level. It built the simulation models of the super-capacitors energy storage system on the PSCAD/EMTDC platform after analyzing the charge-discharge characteristics of the super-capacitor. And then it designed the control strategies as well. The correctness and the effectiveness of the designed models and the control strategies were verified in the end.