.ModelicaAdditions.Blocks.Continuous.ButterLow

Information

This block defines the transfer function between the input u=inPort.signal[1] and the output y=outPort.signal[1] as an n-th order low pass filter with Butterworth characteristics and cut-off frequency f. It is implemented as a series of second order filters and a first order filter.

If transients at the simulation start shall be avoided the states x1 and xr need to be initialized with the start value of the input signal and the states x2 need to be initialized with zeros.

     y = PT21*PT22*...*PT2(n/2)*PT1 u

Release Notes:

• October 17, 2002 by Christian Schweiger:
  Changed to block. Therefore made some variables protected, others changed to output variables.
• June 28, 2001 by Michael Thümmel:
  Realized.