Method for early detection and anticipatory control of consumer-end load shedding in an electrical grid, and apparatus for carrying out the method

1. A method for early detection and anticipatory control of consumer-end load shedding in a single-phase or polyphase electrical grid supplied with single phase or polyphase by at least one generator driven by at least one rotating machine, the method comprising:

measuring a current and a voltage, the current and the voltage being measured between the at least one generator and the electrical grid, in the electrical grid or at both locations;

deriving at least one signal from the measured current and voltage;

using the at least one derived signal and a gradient signal generated from the at least one derived signal to at least partially reduce a load on the at least one rotating machine,

wherein the at least one derived signal and the gradient signal are sent to a regulator of emitted power of the at least one rotating machine so as to influence a power output of the at least one rotating machine during a load shedding in the grid; and

subsequently matching a generation of and demand for electric power.

2. The method as recited in claim 1 , wherein at least partially reducing the load includes controlling a power output of the at least one rotating machine using an actuator connected to the regulator, wherein the at least one rotating machine is a turbine.

3. The method as recited in claim 2 , wherein the turbine is a steam turbine, and wherein the controlling includes controlling a supply of steam to the turbine.

4. The method as recited in claim 2 , wherein the turbine is part of a gas turbine, and wherein the controlling includes controlling a supply of at least one of fuel and combustion air to the gas turbine.

5. The method as recited in claim 2 , further comprising amplifying the at least one derived signal in an output stage before the at least one derived signal is sent to the regulator.

6. A method for early detection and anticipatory control of consumer-end load shedding in a single-phase or polyphase electrical grid supplied with single phase or polyphase by at least one generator driven by at least one rotating machine, the method comprising:

measuring a current and a voltage, the current and the voltage being measured between the at least one generator and the electrical grid, in the electrical grid or at both locations;

deriving at least one electrical variable from the measured current and the measured voltage;

calculating a rate of change of the at least one electrical variable; and

using the at least one derived electrical variable and the rate of change of the at least one electrical variable to at least partially reduce a load on the at least one rotating machine,

wherein the at least one derived signal is used as soon as the calculated rate of change overshoots or undershoots a threshold value.

7. The method as recited in claim 6 , wherein the at least one electrical variable includes at least one of a real power, a real current and a reactive power and a reactive current, and wherein the calculated rate of change includes at least one of a real power gradient, a real current gradient, a reactive current gradient, a reactive power gradient and a rotation speed gradient.

8. The method as recited in claim 7 , further comprising computing a plurality of threshold value signals by comparing a calculated rate of change of at least one of one of the reactive current and the reactive power with a respective threshold value; and wherein the deriving the at least one signal is performed by logically linking the plurality of threshold signals to one another in an evaluation unit based on a structure of the electrical grid.

9. A method for early detection and anticipatory control of consumer-end load shedding in a single-phase or polyphase electrical grid supplied with single phase or polyphase by at least one generator driven by at least one rotating machine, the method comprising:

measuring a current and a voltage, the current and the voltage being measured between the at least one generator and the electrical grid, in the electrical grid or at both locations;

deriving at least one signal from the measured current and voltage; and

obtaining at least one electrical variable for the detection of the load shedding and a rotation speed gradient of a rotor of the at least one rotating machine from the measured current and voltage; and

using the at least one electrical variable and the rotation speed gradient of the rotor to generate a load reduction signal for controlling the at least one rotating machine.

10. The method as recited in claim 9 , further comprising calculating an expected acceleration from an instantaneous power and a mass moment of inertia of the rotor.

11. A method for early detection and anticipatory control of consumer-end load shedding in a single-phase or polyphase electrical grid supplied with single phase or polyphase by at least one generator driven by a plurality of rotating machines, the method comprising:

measuring a current and a voltage, the current and the voltage being measured between the at least one generator and the electrical grid, in the electrical grid or at both locations;

deriving at least one signal from the measured current and voltage; and

using the at least one derived signal and a gradient signal generated from the at least one derived signal to at least partially reduce a load on each of the rotating machines,

wherein the plurality of rotating machines are configured to drive a plurality of generators, and

wherein the at least one derived signal is used to influence power generated by the plurality of rotating machines in response to a load shedding of the electrical grid.