Hi,
I'm also working on ups as final year project... Our teacher has guided us to use inverter through H-bridge mosfets ..now it is being bit difficult to where to take an initial start ..which mosfets should use with their specific drivers.. our aim to achieve 1.5KW ups .. Mosfets driver will be operated through microcontroller ...
I am using IRF3205 Mosfets with HIP4081 Driver.. NOw help me which simulator i should use recently using proteus ...and also i dont have dat much idea about how to use microntroller ..
if anyone plz guide me i'll b really thankful to you

 

Why people always choose such easy beginner projects? A 1.5kW UPS...

1. What is the output voltage?
2. What is the output voltage frequency (sorry I don't want to research this)
3. What is the load power factor range? (what kind of load will be connected)
4. Is it a true sine wave output for the inverter?
5. Does it have a bypass?
6. Does it have a static switch?
7. What is the battery voltage?
8. What is the battery autonomy?
9. What is the maximum permitted THD at the output?
10. What is the switchover time from input power to inverter power?
11. Is it an online or offline UPS?
12. What is the input voltage?
13. Does the input needs to be isolated from output?
14. which protections shall it include? overvoltage, overload, undervoltage, short circuit, overtemperature etc?
15. How fast shall it respond to load changes?
16. How much can it cost?

These are just some examples (not all applicable to same UPS). Make a complete list of everything you want in that UPS, a list of which behaviour it should show in which condition. Then you start designing. This is not a small project if you want it well done.

 

I think you should with basic first, like me...
IRF540 i have used take a old transformer of Cu from UPS (Modified Sin wave)
I have made this and tested with 300W load with 12V 7Ahr battery( max given current was 15A only i think from battery)

 

praondevou thank u so much for reply ..
Mainly i'm giving u all my requirements which i know .. Its our project i really dont have any idea how to mke it perfectly owsum .. i want my project to be as a Perfect and complete project no matter how much it would be difficult i will try my best..



Ur Answers are .....
1. What is the output voltage? [Obviously 220V AC]
2. What is the output voltage frequency [50Hz]
3. What is the load power factor range? [It can be either any fans or lamp or a whole system of a room ]
4. Is it a true sine wave output for the inverter? [ yeah i want it true but a modified can be obtained]
5. Does it have a bypass? sorry i dnt know this
6. Does it have a static switch? yup it'll have
7. What is the battery voltage? 12V
8. What is the battery autonomy? 7Ahr
9. What is the maximum permitted THD at the output? [sorry no idea ..will u plz elaborate]
10. What is the switchover time from input power to inverter power?[ i think it will be depending on switching]
11. Is it an online or offline UPS? [online]
12. What is the input voltage? [input from house supply 220V]
13. Does the input needs to be isolated from output? [No idea]
14. which protections shall it include? overvoltage, overload, undervoltage, short circuit, overtemperature etc? [ precautions should be added in order to make it more efficient]
15. How fast shall it respond to load changes? [Sorry no idea as well ]
16. How much can it cost? [ No worry of expenses i just want my project to be perfect]

Once again thank u so much fo reply and i'll b highly thankful to u if u would b helping me in this project

 

RRITESH KAKKAR
thank u so much ..
I'm now finally using IRF630 with ULN 2003 drivers .. currently i'm working on to design H-bridge from these , Drivers will be run through outputs of Microcontroller 8pinAVR Attiny13..
Further informations have been given in previous reply ..
I want to simulate it first on pc but Proteus can't run this simulation due to CPU load help me in this

 

1.5 kW from a battery rated at 12V 7 AH will get you well less than three minutes of backup.
That is not even considering the efficiency of the UPS or the power factor of the various loads.


Is that what your seeking?

 

It will likely not work with such a small battery. You need a battery which is capable to deliver a high current, and the right cables/terminals.

1,5kW @ 12V = roughly 150 Amps (efficiency loss in the dc/dc).
Cables for 150A + terminals are pretty decent.
Even 30A already isn't easy anymore to handle.

 

JoeJester and takao21203
thanku so much fo replies.. U guyz are right battery ratings is also a problem in making such power rated ups..
will u plz suggest any gud1 ??