Damping electromagnetic oscillations in power systems

1. A method of damping multiple electromagnetic oscillations in a power system, comprising:

obtaining phasor data signals from at least one power system location;

analyzing each oscillating mode by modal analysis;

extracting each oscillating mode from within said signals;

damping each oscillating mode based on the analysis; and

applying a control signal derived from the damped oscillating mode to a power flow control device in the power system,

wherein the step of extracting an oscillating mode comprises selecting a mode, and determining a residue having a maximal norm within a matrix of residues of the extracted mode.

2. The method according to claim 1 , wherein the method comprises:

superposing two or more damped oscillating modes to obtain a superposition signal, and

applying a control signal derived from the superposition signal to a power flow control device in the power system.

3. The method according to claim 1 , wherein the step of mode selection comprises obtaining modal controllability and modal observability.

4. The method according to claim 1 , wherein each mode residue represents a product of modal controllability and modal observability.

5. A controller for damping multiple electromagnetic oscillations in a power system (G), the controller comprising:

at least one phasor measurement unit (PMU) obtaining phasor data signals including oscillating mode signals;

at least one power oscillation damper (POD) controller for receiving and damping each oscillating mode signal;

a superposition means for receiving and summing the damped signals and deriving a control signal;

a feedback controller (H) to feedback the control signal to a power flow control device in the power system (G); and

means for extracting each oscillating mode within the phasor data signals, wherein the extracting means comprise a mode selection means and a means for determining a residue having a maximal norm within a matrix of residues of the extracted mode, respectively.

6. The controller according to claim 5 , wherein the at least one power oscillation damper controller is one of a MIMO power oscillation damper controller, a SISO power oscillation damper controller, a SIMO power oscillation damper controller, and a MISO power oscillation damper controller.

7. The controller according to claim 6 , wherein the controller is configured to operate on a wide-area monitoring and control platform.

8. The controller according to claim 6 , wherein the controller is configured to operate on a phasor measurement unit.

9. The controller according to claim 6 , wherein the controller is configured to operate on a power flow control device.

10. A computer-readable recording medium having recorded thereon a computer program for damping multiple electromagnetic oscillations in a power system, the computer program, when executed by a computer, causing the computer to carry out operations comprising:

obtaining phasor data signals including oscillating mode signals;

extracting each oscillating mode signal within the phasor data signals;

receiving and damping each oscillating mode signal;

receiving and summing the damped signals and deriving a control signal; and

feeding back the control signal to a power flow control device in the power system,

wherein the extracting operation comprises selecting a mode and determining a residue having a maximal norm within a matrix of residues of the extracted mode, respectively.

11. The method according to claim 2 , wherein the step of mode selection comprises obtaining modal controllability and modal observability.

12. The method according to claim 3 , wherein each mode residue represents a product of the modal controllability and the modal observability.