nkinar
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I think that there are actually two equations for the cutoff frequency. For the parallel RCL circuit, the lowpass cutoff frequency (in Hz) will be
fc_parallel = 1 / ( 2 * pi * R *Cbyp )
Alternately, for the series RCL circuit, the lowpass cutoff frequency (in Hz) will be
fc_series = R / (2 * pi * L)
The designer selects both cutoff frequencies so that attenuation is provided. I believe that it is important to select the fc_parallel cutoff frequency prior to the fc_series cutoff frequency. These are two filters that are being cascaded.
Then, the selection of all other values in the circuit is an optimization problem based on the two equations above and the constraints for Rdamp given in the paper.
The required power for Rdamp is calculated simply using the ubiquitous P = I * V equation for power.
As mentioned in the paper, if Cdamp is very large (i.e. 200uF), then the ESL of the capacitor will serve in lieu of using a resistor R; no resistor is required.
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