Calculate Y parameters for nearly ideal transformer

This calculator allows calculation of a set of Y parameters for approximation of a nearly ideal transformer.

y1s or z1s specify the input admittance or impedance of port 1 with port 2 shorted (ie v2=0).

y1o or z1o specify the input admittance or impedance of port 1 with port 2 open (ie i2=0).

These values provide an opportunity to capture some non-ideal behaviour. The calculator assumes that z1s<<z1o.

In the absense of known values, use the defaults.

The calculator does not do a lot of error checking, if you enter nonsense, it will probably produce nonsense.

Model

Fig 1: model

If we assume that Yis>>Yio or Zis<<Zio, we can take y11=Yis-Yio and derive the rest of the Y parameters for an ideal transformer based on the turns ratio. We can then add in half the magnetising admittance Ym/2 at Port1, and refer the other half to Port 2 as Ym'/2 being Ym/2/n^2 at Port 2.

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