TRƯỜNG ĐẠI HỌC SƯ PHẠM KỸ THUẬT
TP. HỒ CHÍ MINH
ELECTRICAL AND ELECTRONIC
PRINCIPLES
WEEK 7, 8
Cuong Q. Ngo
Last classes
• Trigonometric Fourier series
• Plot function - MATLAB
• Circuit Application (Applying Fourier series)
2
Contents (Today class)
• Laplace transform
• Circuit element models
• Circuit analysis
• Transient analysis
3
1. Laplace Transform
• The Laplace transform is an integral transformation of a
function f (t) from the time domain into the complex frequency
domain, giving F (s).
• Where s is a complex variable: 𝑠 = 𝜎 + 𝑗𝜔
4
1. Laplace Transform
• Determine the Laplace transform of
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1. Laplace Transform
• Laplace transform
pairs (f(t) = 0, for t < 0)
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1. Laplace Transform
• Laplace transform
pairs (f(t) = 0, for t < 0)
7
1. Laplace Transform
• Inverse Laplace transform
1. Decompose F(s) into simple terms using partial fraction
expansion.
2. Find the inverse of each term by matching entries in the
previous table.
8
1. Laplace Transform
• Find the inverse Laplace transform of
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1. Laplace Transform
• Answer:
𝑓 𝑡 = 3𝑢 𝑡 − 5𝑒 −𝑡 𝑢 𝑡 + 3 sin 2𝑡 𝑢(𝑡)
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