Buck Converter Control Design

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Buck Converter Control Design

• Sung-yeol Youn
• Electrical Engineering
• Virginia Tech
• December 10th, 2008

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We can obtain following transfer functions by
analyzing steady state and small signal models.


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Open-loop Bode Plots and Output Voltage
Gvd
Gvg
Zo
Vout
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Compensator Design
Gc
Open loop bode plot with Gc
GM 18.3dB PM 54.1deg fc5.93kHz
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Closed-loop Bode Plots and Transfer Functions
Max. Value of GvgCL -24.4dB ? ? V 1.21V
Max. Value of ZoCL 11.6dB ? ? V 3.80V
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In result, the final design satisfies the
instaneous voltage change and settling time
specifications.
20V Input Voltage 1A Load Current
Peak Vo change 0.702V 1.10V
Settling-Time 1.037ms 1.01ms