Optimal design of passive tuned filters for time-varying non-linear loads

This paper presents a new method for designing passive filters by using a minimization technique for time-varying nonlinear loads. The proposed procedure takes into account the non-convex behavior of any objective function in case of considering harmonics below the tuned frequencies of the filters. Hence, it is always assured that the optimal filter is obtained with respect to an optimization criterion. The method is completed with additional restrictions, which consider the position of the resonances introduced by the filters and the injected fundamental reactive power. Applying these restrictions, the designed filters are immunized against the parameter changes. Moreover, the facility including the passive filters does not inject fundamental reactive power to the power system.