Damping power system oscillations by unidirectional control of alternative power generation plants

The paper shows the potential that alternative power generation plants have to damp oscillations in large electrical power systems. Electrochemical fuel cell, gas turbine, wind turbine, solar, photovoltaic, etc. plants can provide local damping when they inject power in proportion to the frequency deviation from the standard reference. The damping is introduced through the power electronic converters that most alternative power plants use to interface with the power system. Another important contribution of the paper is the use of a unidirectional damping strategy with only absorption (or injection) of power. As a feasibility study, the goal of the paper is to evaluate the necessary size (as a fraction of the overall power) that the Alternative Power Generation Plants (APGP) must have to damp out system oscillations in a few seconds. Examples on power systems of two, six and thirty-nine nodes are presented for illustration.