Homework 4 announcement

Homeworks/Homework 4/README.md

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+# EE 463 Homework#4
+
+## DC/DC CONVERTERS
+
+### Deadline: 18/01/2023 23:59
+
+Please check [evaluation.md](evaluation.md) for other details and evaluation criteria about the project. Open a **private repository**, which you will put all your work into. Please add [me](https://github.com/OgunAltun) as a collaborator.
+
+<br />
+
+**1) Buck Converter**<br />
+
+A step-down DC/DC converter will be used in regulated power supply. The specifications are; the input voltage range is 12-24 V and the output voltage is fixed at 5 V. The output voltage control is maintained by means of feedback control. The switching frequency is selected as 500 kHz. The L and C filter components are given as 5 µH and 10 µF. Assume ideal components, ignore all parasitic effects and assume ideal switches.
+
+
+**a)** Find the load current that guarantees CCM operation under all operation conditions. Don't just use the formula; derive your steps.
+
+**b)** Assume that rated output power is 15 W. Calculate the maximum inductor current ripple and output voltage ripple for the given input voltage range.
+
+**c)** Simulate the steady-state behaviour of the converter and show the important waveforms for boundary conduction mode with 24 V of input voltage. Plot following waveforms and comment on the results.
+* Inductor voltage and current
+* Output voltage
+* Diode voltage and current
+* Switch voltage and current
+
+**d)** Repeat part-c with 12 V input and 1 W output power. Comment on the results.
+
+**e)** What is inrush current, define it. Considering the case in part-d, what is your inrush current at input current for this case. Propose a method to avoid inrush current and implement your solution to your simulation model. Compare the results by plotting the cases in this part and part-d.
+
+**f)** Now, consider that the output capacitor has 50 mΩ ESR. Simulate the converter for boundary conduction mode with 24 V of input voltage. Compare the results with ideal case of part-c. Comment on the effect of adding capacitor ESR to the converter parameters such as output voltage ripple. Also, offer a solution to decrease the equivalent ESR of the output capacitor and to reduce the output voltage ripple.
+
+**2) Boost Converter**<br />
+
+In step-up DC/DC converter, let input voltage range be 5-12 V and output voltage be 16 V with switching frequency of 300 kHz. Assume that rated output power is 16 W.
+
+**a)** Consider all components as ideal. Calculate minimum inductance that will keep the converter operating in the CCM operation for rated output power.
+
+**b)** Calculate the output capacitance for peak-to-peak voltage ripple less than 2% under rated output power.
+
+**c)** Simulate the steady-state behaviour of the converter and show the important waveforms for boundary conduction mode of part-a. Plot following waveforms and comment on the results.
+* Inductor voltage and current
+* Output voltage
+* Diode voltage and current
+* Switch voltage and current
+
+**d)** Assuming the switches and capacitors are ideal, but the inductor has 30 mΩ ESR, and considering the load resistance is equal to the rated load resistance, derive the voltage gain as a function of the duty cycle. Show your steps clearly. On the MATLAB, plot the voltage gain with and without ESR on the same graph as a function of duty cycle. Comment on the results.
+
+**e)** Repeat the same steps in part-d for the converter efficiency.
+
+**f)** Choose commercial semiconductor products using Digikey that is appropriate for your design. Calculate the losses on these devices for rated power operation with 12 V input voltage. How would losses on the diode and switch change if the duty cycle is increased? Explain in detail.
+
+**g)** Using the calculated loss values, construct a thermal lumped element model and estimate the junction temperature without a heatsink. If necessary, choose a thermal interface material and heatsink and find out the junction temperature with these materials. Clearly state any assumption that you made.

Homeworks/Homework 4/Teams.md

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+# Homework 1 Team Members
+
+Random generated teams are announced below. It is your responsibility to find your team member.
+If you can not contact your team member, please let me know as soon as possible. Individual homeworks will not be accepted.
+
+| Team No 	| First Member          	|   Second Member       |	
+|---------	|-------------------------	|-----------------	|
+| 1       	|mehmet hakan yel         	|ismail macit
+| 2       	|omer sen            	|ahmet can yulaf
+| 3       	|mehmet emre dogan            	|ahmet furkan gursoy
+| 4       	|ekin arda comez            	|basak koca
+| 5       	|fatih erden           	|isa ersoz
+| 6       	|metehan kucukler           	|isik emir altunkol
+| 7       	|atilla can aydemir     	|yasin enes caliskan
+| 8       	|ahmet bilgin            	|ozgur gulsuna
+| 9       	|selin ezgi ozcan           	|gamze celik
+| 10       	|nilsu bora          	|irem bayin
+| 11      	|arda kasim   	|eminalp koyuncu
+| 12       	|utku deniz altiok          	|ahmetcan akuz
+| 13     	|ozan akturk   	|baris ozgorgen
+
+
+
+If your name is not listed above, please let me know.

Homeworks/Homework 4/evaluation.md

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+## Guideline for Homework #4
+
+Here are the important points for Homeworks: 
+
+- You will complete the project in pairs.
+- You are required to create one Github repo in one of the team member's account. Then please add Ogün (/OgunAltun) as contributor. Each partner is required to contribute to the work.
+- You can use any simulation software you want, but it is advised to use MATLAB Simulink.
+- At the end of the homework, you are required to submit a report (in PDF) to ODTUClass. Both this report and your source files in the GitHub repo will be used for grading.
+- Reports will be checked using Turnitin, and copying will not be tolerated. Even if you find a report, so that you can inspire, you are limiting of what you can learn from this course. Don't fool yourself, and do your projects with your team member only.
+- Late submissions will be available in 1 days after the deadline but the homework will be graded over 85 pts. (-15% reduction for late submissions)
+
+## Evaluation
+
+The homework will be evaluated using the following guideline:
+
+**Number of Commits (15%):** The number of edits of your homework files as seen from the contributors list. For example, if you start making your homework in the last few days, you’ll get no credit. If you start early and continue editing your files, you’ll get full credit. The projects/homeworks are time consuming, so this is a way to encourage you to start early and work regularly. Note that, each student will be evaluated separately according to personal commit number.
+
+**Report Quality (Pass with multiplier or Rejection):** Text explaining your design decisions, quality of your figures, citing relevant studies and your conclusion section.
+
+**Technical Level (85%):** The detail level of your simulations and your conclusions.
+
+## Number of Commits:
+
+In this project the minimum expected number of commits on different days is 2. Each days you made at least one commit is 5 points (saturating at 10 points).  The following rules apply:
+
+- Each student will be evaluated personally. So please make sure each team member contributes.
+
+- Your commit has to be a meaningful, and considerable amount of change has to be made compared to the previous version. For example, just changing a few words in your report is not a meaningful commit.
+
+- Number of days that you committed will be evaluated by common sense. For example, a commit at 23:58 and another commit at 00:02 will still count as one.
+
+- Do not try to find a workaround. Just spend time on your project, and improve your models regularly and it should be fine.
+
+You'll get 5 points from the content of your commit messages. You are supposed to write clear and explanatory commit messages, listing what  specific improvements that you made in that version. Please have a look at the following links:
+
+- [Writing Good Commit Messages](https://vip.wordpress.com/documentation/commit-messages/)
+
+![](https://imgs.xkcd.com/comics/git_commit.png)
+
+## Report Quality:
+
+You report quality will be evaluated using the following criteria:
+
+- The report has a separate title page
+- The report has an introduction section that briefly explains the content and the aims of the report
+- The report organized properly with clear sections and subsections
+- All figures and tables have proper captions
+- Figures are given with white background
+- The graphs have proper axes labels and font size of labels is adequate
+- No grammar/spelling errors and very well-written report (hint: use spell-check, Grammarly
+- Use *Export Figure* command of MATLAB instead of screenshot
+- No equations or any comments presented as a photo of written copy
+
+According to mentioned quality criteria, your report will be multiplied by a number beween 0.9-1. If the report is not qualified well enough, the report will be rejected and students will be asked to resubmit the report in 1 day. The second submissions or late submissions will be evaluated over 85 pts.
+
+## Technical Level:
+
+Following grades will be applied for the technical parts:
+
+- Q1: 45 pts
+	- a) 5 pts
+	- b) 5 pts
+	- c) 9 pts
+	- d) 9 pts
+	- e) 8 pts
+	- f) 9 pts
+
+- Q2: 55 pts
+	- a) 5 pts
+	- b) 5 pts
+	- c) 8 pts
+	- d) 11 pts
+	- e) 11 pts
+	- f) 7 pts
+	- g) 8 pts
+
+