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Generate Bus Admittance Matrix

For any power system containing n buses,

\[\begin{equation*} \begin{bmatrix} I_1 \\ I_2 \\ \vdots \\ I_i \\ \vdots \\ I_n \end{bmatrix} = \begin{bmatrix} Y_{11} & Y_{12} & \cdots & Y_{1i} & \cdots & Y_{1n} \\ Y_{21} & Y_{22} & \cdots & Y_{2i} & \cdots & Y_{2n} \\ \vdots & \vdots & \ddots & \vdots & \ddots & \vdots \\ Y_{i1} & Y_{i2} & \cdots & Y_{ii} & \cdots & Y_{in} \\ \vdots & \vdots & \ddots & \vdots & \ddots & \vdots \\ Y_{n1} & Y_{n2} & \cdots & Y_{ni} & \cdots & Y_{nn} \end{bmatrix} \begin{bmatrix} V_1 \\ V_2 \\ \vdots \\ V_i \\ \vdots \\ V_n \end{bmatrix} \end{equation*}\] \[[I_{bus}] = [Y_{bus}][V_{bus}]\]

Formulas for calculation:

For diagonal elements, \(Y_{ii} = \sum_{j=0}^{n}y_{ij}\)

For off-diagonal elements, \(Y_{ij} = Y_{ji} = -y_{ij}\)

where $y_{ij}$ is the admittance of the line between bus i and bus j.

Class Diagram

classDiagram
   class Complex{
      - float real
      - float imaginary
      + Complex(float real,float imaginary) Complex
      + getReal() float
      + getImag() float
      + fromString(String s) Complex
      + findMax(int[] array) int
      + add(Complex other) Complex
      + subtract(Complex other) Complex
      + multiply(Complex other) Complex
      + divide(Complex other) Complex
      + negate(Complex other) Complex
      + reciprocal(Complex other) Complex
      + toString() String
   }

   class Ybus_Java{
      - Scanner sc
      + main(String args[]) void
      + get_input(int choice, int n) Complex[][]
      + calculate_matrix(Complex[][] y, int n) Complex[][]
      + display_matrix(Complex[][] ybus, int n) void
   }


   Ybus_Java --> Complex : uses

Adding annotations for MATLAB and Python implementations:

• note for Complex:
  In MATLAB and Python, inbuilt libraries are used instead of this custom Complex class.\
• note for Ybus_Java:
  The MATLAB and Python versions implement similar functionality using inbuilt functions and data structures.

Documentation

Here are the links to the documentations:

Language	Link
Python	Ybus_python
Java	Ybus_java
MATLAB	Ybus_matlab