Method for operating an energy installation, and an energy system having such energy installations

1. A method for operating an energy installation, the energy installation having a wind turbine or water turbine connected to a generator, a converter unit connected on a generator side to the generator, and an auxiliary energy unit to provide electrical energy to cover an intrinsic energy demand of the energy installation, the converter unit being connected on a grid side to an electric power grid to feed electrical energy generated by the generator into the electric power grid via the converter unit, and the auxiliary energy unit being connected to the electric power grid for drawing electrical energy, the method comprising:

drawing electrical energy from an energy storage unit via the auxiliary energy unit in an event of a separation of the converter unit and of the auxiliary energy unit from the electric power grid;

in the event of the separation of the converter unit and of the auxiliary energy unit from the electric power grid, drawing electrical energy from the energy storage unit for an adjustable period of time to the auxiliary energy unit, and then drawing electrical energy generated by the generator to the auxiliary energy unit via the converter unit;

electrically charging the energy storage unit, formed as a capacitive energy store or as a battery, by a charging unit; and

in the event of the separation of the converter unit and of the auxiliary energy unit from the electric power grid, drawing via the charging unit, electrical energy generated by a photovoltaic unit.

2. The method as claimed in claim 1 , comprising:

in an event that the converter unit and the auxiliary energy unit are connected to the electric power grid, drawing by the charging unit electrical energy from the electric power grid and/or from the photovoltaic unit and/or from a wind energy unit.

3. A method for operating an energy system having a plurality of energy installations, wherein each energy installation includes a wind turbine or water turbine connected to a generator, a converter unit connected on a generator side to the generator, and an auxiliary energy unit for providing electrical energy to cover an intrinsic energy demand of the energy installation, the energy installations being connected to one another in series at their converter units on the grid side and connected to one another in series at their auxiliary energy units on the grid side, and the series connection of the energy installations being connected to an electric power grid, the method comprising:

feeding electrical energy generated by the generators of the energy installations into the electric power grid via the converter unit of the series connection connected on the grid side to the electric power grid;

in an event of a disconnection of the series connection of the energy installations or a total separation of the series connection of the energy installations from the electric power grid, drawing energy, by a respective auxiliary energy unit of each energy installation no longer connected to the electric power grid via the series connection, from an energy storage unit provided for each energy installation;

in the event of the disconnection of the series connection of the energy installations or the total separation of the series connection of the energy installations from the electric power grid, drawing electrical energy, by the respective auxiliary energy unit, for each energy installation no longer connected to the electric power grid via the series connection, from an associated energy storage unit for an adjustable period of time, and then drawing electrical energy generated by the generator by the respective auxiliary energy unit via the converter unit;

electrically charging the energy storage unit, formed as a capacitive energy store or as a battery, by a charging unit provided for each energy installation; and

in the event of the disconnection of the series connection of the energy installations or the total separation of the series connection of the energy installations from the electric power grid, drawing electrical energy, by a respective charging unit for each energy installation no longer connected to the electric power grid via the series connection, generated by a photovoltaic unit.

4. The method as claimed in claim 3 , wherein in the event of the disconnection of the series connection of the energy installations or the total separation of the series connection of the energy installations from the electric power grid, providing via at least one auxiliary energy unit, for each energy installation no longer connected to the electric power grid via the series connection, electrical energy for at least one other energy installation.

5. The method as claimed in claim 3 , wherein in an event that the series connection of the energy installations is connected to the electric power grid, drawing via the respective charging unit electrical energy from the electric power grid and/or from the photovoltaic unit and/or from a wind energy unit.