About phasor voltage and phasor current.

AI Thread Summary
Phasor voltage, current, and impedance can be represented as vectors, with voltage being the product of current and impedance. The discussion centers on the process of multiplying these complex numbers, questioning whether it involves dot or cross products. It suggests using complex notation and matrix forms to perform calculations, particularly a 2x2 matrix for complex numbers. The complexity of using a 2x1 vector for these calculations is noted, indicating potential difficulties in tracking the operations. The conversation implies that understanding these concepts is foundational for applications in SPICE programs.
sabbir ahmed
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we know that phasor voltage, current and impedence can be represented by vector. we know phasor v is equals to the product of phasor i and impedence. the what is the process of multiplication? is it dot or cross product?
 
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I have no idea. Do you know how to multiply complex numbers? If I wanted the voltage as a function of impedence and current. I would express impedence, current and voltage as complex numbers.
 
Phrak said:
I have no idea. Do you know how to multiply complex numbers? If I wanted the voltage as a function of impedence and current. I would express impedence, current and voltage as complex numbers.

if complex number can be measured like a vector then why complex multiplication is not dot or cross?
 
sabbir ahmed said:
if complex number can be measured like a vector then why complex multiplication is not dot or cross?

Do the calculations in complex notation and see if you have can convert it to the dot product or real valued vectors.
 
The only way I've ever seen complex numbers in matrix form was like so:

[real -imag]
[imag real ]

So it's a two by two matrix, so if you input the impedance, and current into these equations and do the DOT-PRODUCT, you'll get the voltage in matrix form.

I don't think you can easily do it with a 2x1 vector though. It gets complicated and very difficult to keep track.

Try the matrix thing yourself. It's kind of need. I think this is a building block on SPICE programs, not sure though about that

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Justin Coulston
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TheModernEngineer.blogspot.com
 
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