As clean and renewable energy, Photovoltaic (PV) systems have been developed quickly nowadays. However, high penetration of PVs would cause overvoltage problem. This paper proposes a cooperative real-time overvoltage prevention control, which is managed by a community energy management system (CEMS). The main idea is to suppress the overvoltage by managing the operation schedule of household loads facilitated by the CEMS. The scheduling by CEMS is formulated as a combinatorial nonlinear time-series scheduling optimization problem in which the profit of the whole community is maximized. A fast heuristic search method called local search method is developed for the purpose of real time control. To validate the proposed method, a simulation of one day schedule is carried out on a 20-customers distribution system model.