Participation factor in modal analysis of power systems stability

This paper provides a brief overview on existing approaches for defining participation factor in modal analysis which characterizes the interaction between modes and state variables of power system. We calculated participation factors using different methods and compared the results obtained with the expressions derived from mode evolution. For cases of complex eigenvalues of linear differential equations characteristic matrix it was discovered incorrect existing approaches for defining participation factor of state variable in mode. Modern software applications designed to analyze power system stability widely deploy the approaches discussed that provide incorrect results of modal analysis and pose risks to the operation of real power systems. Therefore the problem of calculating the participation factor remains as important as ever.