ENTRY 2: FYP2 Reflection of progress 2

by MUHAMMAD SAZRUL BIN MOHD SULAIMAN

For this progression, I finish doing all the part by part, which is a rectifier, PFC Boost converter, Bidirectional DC-DC converter, and inverter for the online UPS design. Still, if doing it separately it may be getting the result you desired, but when it combined, it will get an error on the output. Other than that, I do the literature review by finding past research and comparing it with my discussion. I also prepared the draft of the thesis for this project.

WEEK 6

For this week, I am still designing the bidirectional dc-dc converter in Matlab Simulink. As we explained before, the bidirectional dc-dc converter is for charging and discharging the battery. Which will 2 modes known as buck mode and boost mode. Also, it uses for the problem of the high battery bank. Thus, there is flexibility in the choice of the battery bank voltage, making it possible to minimize battery cost, volume, and weight. In addition, low frequency (100/120 Hz) DC-bus voltage ripple can be largely reduced in the battery bank charge process.

So this figure below is my design which is the typical design for the non-isolated bidirectional dc-dc converter.

bidirectional.PNG

By using a timer switch I can set the time that I want to make the circuit undergoing 2 processes which charging and discharging. The result for this is not from what I expected, there must be some error somewhere. This is the result that I obtain for full circuit,

dc output.PNG

output dc 2.PNG

Therefore, I might need to do more literature studies on this circuit in order to generate better output.

WEEK 7

For this week, I’m trying to design the inverter but by not using the PWM generator or the universal bridge. Because I want to compare the output with the normal design and the universal bridge. This type of inverter consists of 4 switching components that are controlled by Unipolar PWM. A low pass filter will be used to eliminate unwanted frequency. In other words, this filter is used to get the pure sine wave due to the output of an inverter that is similar to the Unipolar PWM output.

Then, the design for the unipolar PWM circuit is shown below. With the result before the filter.

INVERTERDIP.PNG

BEFOREFILTER.PNG

 

WEEK 9

So, for this week, I’m trying to combine for all the parts that I have designed before which is consist of the rectifier, PFC boost converter, Bidirectional DC-DC converter, and inverter. From what I have expected if the output from the combination of the rectifier with the boost converter got some error which we need to tune the circuit until we get the value we want. So, I’m still not quite sure about the tuning. I’m still trying to make new calculations and tests. Also, some new literature studies for these ups. It turns up, that my boost converter did not get the result which causing the error for the whole configuration. The rectifier ripple becomes much bigger and the other component did does not get any expected result.

open loop.PNG

WEEK 8

Then, for this week I try to combined the rectifier and the PFC boost converter that I have designed before. Still, the output is not like what I’m expecting. I need to adjust the parameter for the configuration. Because the output for the peak to peak for the rectifier becomes bigger after combined also with the boost converter. Below is the result for the rectifier and the boost converter I have simulated,

BOOST+RECTIFIER.PNG

output rectifier, 

rectifier.PNG

output voltage PFC,

boostconverter.PNG

current for PFC, 

currentPFC.PNG

 

Updated on 15 May 2020, 12:55 AM; 213 page visits from 14 May 2020 to 8 February 2026