High penetration of Distributed Generation (DG) plants in Medium Voltage (MV) / Load Voltage (LV) power grids may lead to abrupt voltage raises. Typical critical scenarios are represented by either low demand conditions or high power production from renewable sources. Traditional approaches used to face such a situation involve both the disconnection of the distributed generators and the curtailment of the generated power leading to several disadvantages. However, new technologies allow an active orchestration between some controllable devices of the grid, e.g. distributed generators, MV/HV transformers, storage devices in order to maintain relevant system variables within prescribed operative constraints in response to unexpected adverse conditions. This work addresses the online management of distributed generators and storage devices. The approach is based on Command Governor (CG) ideas and is based on the resolution at each time instant of an optimization problem containing explicit constraints related to voltage bounds and operational limits of adopted devices.