Analytical tool for designing MMC parameters to improve damping of transients

The analytical tool is based on linearization about the steady-state solution of the nonlinear first order differential equations modeling the MMC. The resultant linear dynamic equation of the perturbation state variables is time periodic. The state-transition matrix is computed by numerical integration and its eigenvalues are applied to determine small signal stability and the sensitivity of the eigenvalues to parameter changes are used as guide in designing damping. The method is based on the Floquet-Liapunov Theorem.