Quadralateral Relay Model
3/21/2005

DFT Filter

Input signal

Cosine Filter

Delayed Cosine Filter

Size of arrays

Sample array (for plotting)

Memory Filter

Filter time constant

Digital Filtering Subroutine

"x" is an array of real
numbers containing the
input data.

Zn is a vector of coefficients
for the filter numerator
polynomial in dessending
powers of 1/z.

Zd is a vector of coefficients
for the filter denominator
polynomial in desending
powers of 1/z.

Returned vector is the filtered
data.

Input Voltage

Input Current

Symmetrical Component Cnstants

Compute peak amplitude Phase and Sequence voltages and currents

Three phase voltage or current from phase to sequence domain

Conversion from mH to reactive ohms

Compute Symmetrical Component impedance

ZLp is the phase line reactance for
the entire line length.

Compute source impedance matrix for S Bus

(Primary)

Compute source impedance matrix for R Bus

(Primary)

Zapp is just simply "V/I"

Compute S and R bus source inductance (primary) for back loading into ATP line model

No Compensaton

Mho circle plotting constants

Homogenious Line

Fault Current Approximation

Non homogeneous Line

Fault Current Approximation

No Homogeneous Line with Angle(T) compensation

Fault Current Approximation

Fault Current Approximation