Symbolic Expression of Damping Factor and Damping Resistance of Passive High-Pass LCL Filters

A procedure for computing the damping factor and damping resistor of passive high-pass LCL filters is presented in this paper. Both the numerical values and the symbolic expressions can be computed in this way. The procedure is based on a symbolic LR algorithm able to compute both the numerical values and the approximate symbolic expressions of poles and zeros of a circuit. Using these expressions, a designer can rapidly choose the optimal set of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\boldsymbol{R}_{\boldsymbol d}-C_{d}$</tex> values to fulfill an imposed damping factor.