Real-time assessment of power system transient stability using rate of change of kinetic energy method

The effectiveness of the rate of change of kinetic energy (RACKE) in defining power system stability was studied previously using off-line computer simulation. Theoretical analyses indicated the effectiveness of this method in deciding transient stability of power systems, and its effectiveness in increasing the stability margin when a dynamic brake element is used. The practical implementation of the RACKE method with a resistive dynamic brake is presented. The brake insertion and removal instants are decided on-line by a microcomputer controller. The hardware and software design considerations of the proposed controller are described. The observed behaviour of the power system prototype during fault conditions is found to be in agreement with that obtained from simulation tests.