The Y-editor for network analysis withTi-84 Plus (CE)
Explanation of how to use the Y-editor for complex calculations
The Y-editor is a powerful tool for Electrical Engineering acting as formula editor also for complex functions. An example is demonstrated to illustrate the method. Assume we want to calculate the source current i of the following electric circuit. Step by step, using the Y-editor, this problem will be solved.
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The first step is to calculate the complex impedance of capacitor C1 using Y1 of the Y-editor.
1: Y1=1/(iX*0.1E-6), where X= the radial frequency (rad/sec), i= the complex unity vector (For Ti84 the symbol i=used for j). 0.1E-6 Farad is the capacitor value of C1.
The impedance of resistance R2 in series with L2 is stored in Y2.
2: Y2=0.1+iX0.3E-3 with 0.1 is R2 and 0.3E-3 is the inductance value of L1. As no plots of complex functions can be made with the Y-editor, the = key of the Y1, Y2, etc. are disabled. See the example.
The parallel impedance Zp of C1 and R2+ inductance L1 is calculated in Y3 with next formula.
3: Y3=Y1*Y2/(Y2+Y3). You find Y1, Y2 with the key VARS- Y-Vars-Function-Y1 etc.
The total impedance of the Network is stored in Y4=R1+iX*L2+Y3
4: Y4=5+iX1.3E-3+Y3. Don't forget to disable the = key of Y3 and Y4.
The current can be calculated by i=V1/Ztot and is calculated with
5: Y5=1/Y4 (disable =key of Y4).
The absolute value of the current is calculated with Y6
6: Y6=abs(Y5).
Don't disable the = key of Y5 because this function is plotted.
Use the window key and give the frequency area in Xmin and Xmax (10-100000) and choose Zoom-ZoomFit and the plot will appear. See the figures below. In the same way, the angle of the current can be plotted with the use of: point 7. To fit on the same screen as the current, the angle is divided by 1000
7: Y7=angle(Y5) /1000
Don't disable the = Key of Y7.
Of course, you can do more detailed calculations. For example, the absolute capacitor voltage = total current i* Zp
8:Y8= abs(Y5*Y3)
Plot of the source current amplitude (green) and the phase /1000 (red) as function of rad frequency. Green: current, red: phase. The angle is divided by 1000 to get amplitude and phase in 1 screen. Maximum current equals 0.144552 A @ omega= 640689 rad/sec and a maximum phase of 0.0819*1000=81.9 degrees @ 60033 rad/sec.
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The method is also used for filter design and Bode diagrams and is explained on the pages :