Lab 001 - High Voltage

% Data from the lab
    % Gap distance
    d = (1e-3)*[2 3 4 5 6];
    % Negative DC BD volt
    Dc_neg = (1e3)*[6.4 9.5 12 13 14.5];
    % Positive DC BD volt
    Dc_pos = (1e3)*[7.6 10 14.5 15 17];
    % AC BD volt
    Ac = (1e3)*[5.5 7.4 8.8 10.1 11.8];

%Using the poly fit function to get the approximated curves (polynomials)
    % I will take gap distances form (1mm) to (10mm) with step (1 micro m)
    d_fit = [0.001:0.00001:0.01];
    % Using the polyfit
        p_Dc_neg = polyfit(d,Dc_neg,1)
        p_Dc_pos = polyfit(d,Dc_pos,1)
        p_Ac     = polyfit(d,Ac,1)

% Getting the y axis values using the approximated polynomials
    Dc_neg_fit = polyval(p_Dc_neg,d_fit);
    Dc_pos_fit = polyval(p_Dc_pos,d_fit);
    Ac_fit = polyval(p_Ac,d_fit);

% Plotting the curves and the practical points
    %Dc negative curve
    subplot(3,3,1);
    plot(d_fit,Dc_neg_fit,'--b',d,Dc_neg,'ob'),xlabel('Gap Distance'),ylabel('BreakDown Voltage');
    title('Negative DC BreakDown Voltage Vs. Gap Distance'),grid on,legend('DC Negative','DC Negative(practical)');

    %Dc positive curve
    subplot(3,3,2);
    plot(d_fit,Dc_pos_fit,'-r',d,Dc_pos,'or'),xlabel('Gap Distance'),ylabel('BreakDown Voltage');
    title('Positive DC BreakDown Voltage Vs. Gap Distance'),grid on,legend('DC Positive','DC Positive(practical)');

    %AC curve
    subplot(3,3,3);
    plot(d_fit,Ac_fit,'k',d,Ac,'ok'),xlabel('Gap Distance'),ylabel('BreakDown Voltage');
    title('AC BreakDown Voltage Vs. Gap Distance'),grid on,legend('AC','AC(practical)');

    % All
    subplot(3,3,4:9);
    plot(d_fit,Dc_neg_fit,'--b',d,Dc_neg,'ob',d_fit,Dc_pos_fit,'-r',d,Dc_pos,'or',d_fit,Ac_fit,'k',d,Ac,'ok');
    xlabel('Gap Distance'),ylabel('BreakDown Voltage')
    title('Positive,Negative DC and Ac BreakDown Voltage Vs. Gap Distance'),grid on;
    legend('DC Negative','DC Negative(practical)','DC Positive','DC Positive(practical)','AC','AC(practical)');