Using transformer for gate drive is not a cheap solution.If you add your problem while using transformer,cost will be more. At least I find while testing. Ir2110 costs same as mosfet in Bangladesh and so, I don't find it costlier.I don't understand why you should not use modern ready made gate driver ics for saving few pennies. Alexsch has properly pointed out and I do agree with him.
Ir 2110 is having 2A gate driving current which is 4 times greater than sg3525. I think this amount of current is enough for making an Inverter with a capacity of 5 KW. Are you thinking in the line of making inverter of 10 kw capacity? Then you are right. I am discussing regarding an inverter <= 500 watt capability.
Creating 1 Amp is not problem. Problem is using 1A in lieu of mA in the circuit. When every body is trying hard to make the circuit smaller by infusing less current, then what is the use of making bulky current eating transformers? I find it is beneficial in using mosfets.
Nobody is forcing anybody to accept anything. Logic is forwarded so that good sense can be applied. It is up to the individual to accept the better and modern ones instead of sticking to the past and continue to use old but inefficient products.
If you want to stick to use transistors, switch to ESBT which is more efficient and requires mA of current for gate/base drive.
hi golam , since u asked why i m after transformer gate driver, cos i m designing a class d half bridge inverter for 50 hz sine wave , as its a half bridge so to produce 310 v ac pick , i need 620 v dc (+310 - 0 -310), now its lots of voltage to kill the whole driving stage if one of the igbt fails, and there is a very good possibility that they would explode on design phase , i dont want to change the whole control system every time mosfet or igbt fails, transformer will keep the voltage away from control stage and save my invest,
u r rite i m looking at 10kw, i already archive 1kw , without much problem,
u r rite i m looking at 10kw, i already archive 1kw , without much problem,
Thank you Golam, Luka, Areza and everyone who helped.
I have just completed the step up section of my SMPS IPS. I rewound my transformer according to the details provided by Golam, have used IRF3205 as suggested by Areza and I thank Luka for his suggestions. I have used 30kHz oscillator with SG3525 and the step-up section has been tested successfully with converting 12v dc to 240v dc and 300W load. It is working perfectly and no significant heat is produced.
Now I am moving onto the Full Bridge circuit for making this 240v dc to 220v ac. I will attempt both gate driver and MOSFET as well as MJE13009.
I have just completed the step up section of my SMPS IPS. I rewound my transformer according to the details provided by Golam, have used IRF3205 as suggested by Areza and I thank Luka for his suggestions. I have used 30kHz oscillator with SG3525 and the step-up section has been tested successfully with converting 12v dc to 240v dc and 300W load. It is working perfectly and no significant heat is produced.
Now I am moving onto the Full Bridge circuit for making this 240v dc to 220v ac. I will attempt both gate driver and MOSFET as well as MJE13009.
That is benefit of living in countery where everything is less expensive and lower tech (Please take no offense , I have nothing against that, just trying to point out, more money you have more you going to pay for stuff you buy) IR2110 here is in one store: 5,34 €, other one in my city: 3,0875€ if they have it, or they order it and you have to pay 50% moregolam said:
This trafos are very small, smaller then IR, you have them in PC supplys and don't say they are big and current demanding...no more then IR is
I think you need not to worie, since you start small and go up from there, only when you know that everything is working ok you go for higher voltage... IR would be easy to start with, but you need to make it robust for such application, where gate trafos are probably indestructable +areza said:
you get insulation, which is great if you have control circuit on secondary side, you can sense voltages by simple voltage deviders, sense current, all that
hi areza,
thanks. I am very happy that you have made 1 KW inverter. I am happy. But sometimes your postings create some confusion. Sorry. I don't post here to show what I am doing or I can do. My aim is to help those like Tahmid who are at the preliminary stage and need our help for moving forward. I am actually giving him the tips what I have done few years before so that he/others can start from lower level.
I am engaged in smps and embedded system designing for Industrial Automation. I actually design smps with Pic Microcontroller- Pic 18f series ,not with discreet ics.
I produce micro controller based inverter for Butt Welding M/C, high frequency inverter for Induction Heating etc. Recently I have tested my Single Microcontroller based sine wave inverter -upto 1.5 kw for consumer purpose with ETD-49 core. Shortly I will market my sine wave inverter or I may sale my technology as discussion is going on with a renown Company.
I also will try to open a new thread here for making smps with Pic Microcontroller- not using discreet Ic only.
CLEARING DOUBTS REGARDING HALF- BRIDGE CONFIGURATON
Probably you are not clear about inverter configuration. Half Bridge does not require 620v(310-0-310) but only 310 volts as in half bridge configuration, full windings are used, not half windings like push-pull. So, you do not require center tapping and 620v (310-0-310v ) rather 310v in opposite phases. So, you require a mosfet like irfp460 which can handle 500v. If you don't understand what I said and stick to 620v, your mosfets always will blow away and your 1k inverter will not see the light of the day.
Luka said that we are in low tech country but all of us are not working with low tech. Certainly, some of us are talking big with shallow knowledge.
Again, if I hurt you regarding my posting, I am sorry.
Hi
Nice to hear someone is using uC to control, I must say if you know what to write for program it must be really "easy" to make it better and better. Hope you will show some pic of anything sometime
I know it would come out like that, hope you know what I mean, hope no bad filling, I wouldn't want that. I would also try to help as much as I can to anybody that would need help.
Nice to hear someone is using uC to control, I must say if you know what to write for program it must be really "easy" to make it better and better. Hope you will show some pic of anything sometime
hi golam , sorry to make u confuse, if u have a look on some application notes from some semiconductor manufacture and some power amp manufacture (crown, ir , st etc)
on there proprietary topology and general design then u will se what i m talking about, class d need split power supply, a single power supply with capacitor split bus would cause imbalance and catastrophic failure,
please make your self educated enough before u comment on some thing on this forum,
evidently you dont know what you are talking about power electronics and microcontroller,
on there proprietary topology and general design then u will se what i m talking about, class d need split power supply, a single power supply with capacitor split bus would cause imbalance and catastrophic failure,
please make your self educated enough before u comment on some thing on this forum,
evidently you dont know what you are talking about power electronics and microcontroller,
areza,
You said class d requires split power supply, that is +310v and -310v with a common ground. This is actually 310v in two different phases, one positive, the other negative. 620v will be found if measured at -310v reference, not ground reference. Thus, I think that it is improper to call this 620v, but should be referred to as +/- 310v.
And, each MOSFET should be capable of at least 500v or more if possible, but 620v is not competely necessary, as each MOSFET will actually be tackling either +/-310v. 500v will suffice.
You said class d requires split power supply, that is +310v and -310v with a common ground. This is actually 310v in two different phases, one positive, the other negative. 620v will be found if measured at -310v reference, not ground reference. Thus, I think that it is improper to call this 620v, but should be referred to as +/- 310v.
And, each MOSFET should be capable of at least 500v or more if possible, but 620v is not competely necessary, as each MOSFET will actually be tackling either +/-310v. 500v will suffice.
Areza,
Actually you are correct. I know very less regarding Power Electronics and Microcontroller because still I am learning and could acquire very less till today. Still I am learning from Luka, Tahmid and all others and also from you and others. But could not get some, as their teaching is confusing. This is a vast field and I hope to learn till death. I will try to educate myself specially learning lessons from your postings before commenting in the forum. Thank you again for your valuable advice.
Actually you are correct. I know very less regarding Power Electronics and Microcontroller because still I am learning and could acquire very less till today. Still I am learning from Luka, Tahmid and all others and also from you and others. But could not get some, as their teaching is confusing. This is a vast field and I hope to learn till death. I will try to educate myself specially learning lessons from your postings before commenting in the forum. Thank you again for your valuable advice.
Areza,
There is also a confusion/miscalculation regarding your 10kW inverter.
You mentioned that you are using 600v 15A IGBT.
You are using 310v across each IGBT and maximum amperege is 75% of the capacity (you should not use more than 75% of a semiconductor's capacity for safety purpose) that is ~12.5A. This stands at a maximum power capability of 310v X 12.5A = 3.875kVa. And even if you use maximum capability, 15A, you get 310V X 15A = 4.65 kVA.
How do you expect to achieve 10kW (not 10kVA) power from your configuration? There will also be some power losses through different components. So power capability gets even lower. How do you expect to achieve 10kW from this configuration?
Hope you will make it clear so that I can learn from you.
There is also a confusion/miscalculation regarding your 10kW inverter.
You mentioned that you are using 600v 15A IGBT.
You are using 310v across each IGBT and maximum amperege is 75% of the capacity (you should not use more than 75% of a semiconductor's capacity for safety purpose) that is ~12.5A. This stands at a maximum power capability of 310v X 12.5A = 3.875kVa. And even if you use maximum capability, 15A, you get 310V X 15A = 4.65 kVA.
How do you expect to achieve 10kW (not 10kVA) power from your configuration? There will also be some power losses through different components. So power capability gets even lower. How do you expect to achieve 10kW from this configuration?
Hope you will make it clear so that I can learn from you.
tahmid @ i m not questioning , i m just looking for batter topology and ideas, look for some appnote on class d then u will understand what I m trying to point out, I already have the required semiconductor and some of magnetics I need, the half bridge controller will se +/-310 v = 620 v , u got the point?
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