Procedures to prevent the disconnection of a park of electricity generators from a network in the event of a voltage sag, through which, upon detection of the sag, the voltage travelling to the network is controlled in proportion to the magnitude of the sag; the active power produced by the park, rather than sent to the network, is thus diverted into to storage and/or energy dissipation equipment, keeping the park voltage at a nominal level.The invention also includes a device for carrying out procedures integrating a bypass, transformer, static inverter, static converter, capacitance and dissipation resistance unit, voltage sag detection circuit and control circuit.