EACH GROUP WORKS INDEPENDENTLY FROM OTHER GROUPS.
Choice of Non-Isolated Converters:
1. Buck
2. Boost
3. Buck-boost
Choice of Transformer-Isolated Converters:
1. Full bridge buck derived
2. Full bridge boost derived
3. Forward (4 transistors)
4. Forward (2transistors)
5. Flyback
6. Cuk
7. Push-pull buck derived
8. Push-pull boost derived
Choose Buck & Flyback.
EACH GROUP CHOOSES ONE ISOLATED CONVERTER AND ONE NON-ISOLATED CONVERTER
A. Specifications:
Choose your own (realistic) specifications (NOT SHARED WITH OTHER GROUPS). (i.e. Choose input voltage, output voltage, duty cycle(s), inductances, Capacitances, output power, estimated critical switching frequency, inductor current ripple, capacitor voltage ripple, (N1/N2 or N1/N3 if applicable) etc.)
B. Snubber Design:
Explain the transistor and diode turn-on and turn-off switching transient waveforms in your NON-ISOLATED converter. Estimate the switching losses including those due to reverse recovery.
Show the switching transient waveforms from simulation before adding turn-on-turn-off snubbers. Select the appropriate turn-on-turn-off snubber type(s) and size(s) to be used and explain where to place. Then show by simulation the operation without the snubber circuit(s) and after adding the snubber circuit(s).
C. Magnetics Design:
Using the Kg or Kgfe methods of Ch.14 and Ch.15 (respectively), design all filter and transformer magnetics including core type, core size, winding gauge size, number of turns, etc. You must show all steps and used equations in detail. Use the magnetics tables for your design. Put all used equations in MATLAB, MATHCAD, or EXCEL files to generate the results.
D. Sinusoidally Modulated PWM Voltage-Source Inverter
Design a dc-to-ac sinusoidally-modulated PWM voltage-source inverter. Select reasonable specifications. Then, simulate your inverter and observe the output waveform. Explain the gating procedure and how you can increase and decrease the output voltage magnitude by varying the modulation. Support your explanation with simulation results.
E. Analysis and Discussion:
Discuss the operation of your converters as well as the effect of changing the different circuit parameters. For the transformer-isolated converters ex lain how our converter transformer is reset.
Show the effect of varying the duty cycle on the operating point, output voltage, ripples, efficiency, etc. Also show the effect of varying the load on the operating point, output voltage, ripples, efficiency, etc. Finally, show the effect of varying the switching frequency on the operating point, output voltage, ripples, efficiency, etc.
Compare and contrast the performance of your converter isolated with your non-isolated version of your converter s. Support your comparison by simulation. Explain the benefits of transformer isolating your converter.
F. Conclusion: Give your conclusion and explain the experience you acquired after completing this project.
Your results must be presented in report form including:
1. A 20 min (MAX) presentation
2. Full Report:
a. Title page
b. Table of contents
c. Introduction including the objective of the assignment
d. List of figures
e. All pages numbered
f. All figures labeled and captioned
g. All equations numbered
h. Simulation and results section
i. Analysis and Discussion
j. Conclusion
k. List all references
I. Submit softcopy of:
i. Report and Presentation
ii. Pspice , PLECS, Simulink, files etc.
TEXTBOOK - FUNDAMENTALS OF POWER ELECTRONICS, 2ND ED. ERICKSON/MAKSIMOVIC.