A coordinated control strategy for photovoltaic systems（PVs）and controllable loads is proposed，with which the net power output of the coordinated control system can be flexibly adjusted and high-capacity characteristics of controllable loads can be used.By solving a mixed integer programming problem，the reference power output of PVs and operational conditions of controllable loads can be determined.With the quadratic interpolation based active power control strategy，each PV can track its reference power output，and the net power output power of the coordinated control system can be flexibly adjusted.Externally，the coordinated control system behaves like the conventional hybrid energy storage system，with characteristics such as the fast charging/discharging speed.In addition，it has such exclusive advantages as large capacity and low cost.The feasibility of the control strategy proposed is verified by simulation results.