Patent ID: 9013067
Filing Date: 2015-04-21
Classification: H02J,Y02E

Abstract:
1. Method for automatic stabilization of an electric power supply network system comprising a network and at least one converter adapted to exchange maximum transferrable power with the network at steady state stability limit of the electric power supply network system by change of real current flowing between the network and a converter through a stabilizing controller, whereby the necessary direction of current change is determined through real-time stability analysis comprising the following steps: determining at least two electrical main circuit quantities, forming derivatives of the at least two main circuit quantities with respect to time, comparing the signs of the derivatives, and generating a steady state stability limit detection signal in dependency on the outcome of the comparing step, wherein the change of the current direction is achieved by reversing a control loop feedback sign of the stabilizing controller via application of the generated stability limit detection signal, and wherein the stability limit detection signal is generated by comparing the signs of gradient values of real power with respect to time with the signs of gradient values of a second real power dependent quantity with respect to time and if the signs are different the stability limit detection signals is set to a true value and if the signs are equal the stability detection signal is set to false.