Which one is best for Inverter, IGBT or MOSFET?

Hi....... friends....

i'm going to design 12V DC to 230V AC 1KVA inverter.

For this igbt is best or mosfet?

Suggest me to use anyone with good reliability.

Thanks........

Hello,

For the power switch at 12V, the mosfet is the best device, simplest drive and lowest on-state loss.

IGBT has a fixed voltage drop, so your efficiency will be significantly less w.r.t. the mosfet. IGBT is nice for voltage above 300V, depending on required current

Also I believe MOS are easier to drive than IGBT. the only thing is that they have power limitation

Hi, if you are building a low power like 1kv it will be easier to use mosfet.

Hi love_analog,
Can you explain it pls?
Tnx & greetings!
K.

Hi, Karesz.
Although both MOSFET & IGBT have gate breakdown voltage 20V, some 30V, there are differences.
In order to turn MOSFET on, you apply about 10V to the gate, any more will have little benefit - the turn-on curve is "flat" above about 10V, you'd be just worsening the loses in gate drive.
On the other hand, IGBTs are often driven to 15V at the gate, their turn-on requirements are a little different.
To turn a MOSFET off, you simply drop the gate voltage to source potential, relative 0V.
IGBTs may be more tricky to turn off, sometimes you need to pull it about 5V below source, for a reliable turn-off (at least in some applications; inductive loads may require this; i'm not sure .

In the end you'll need to be able to charge/discharge about 150-200% gate energy and possibly dual voltage to drive IGBT compared to MOSFET. Not to mention that driving a device with 15V at the gate is dangerously close to it's breakdown limit.

Review some datasheets of both MOSFETs and IGBTs and look up the "Transfer characteristics" graph, you'll see the difference.

The power limitation of MOSFETs, besides breakdown limits, is inherent to the fact that their conduction losses are resistive - more volts, more heat. IGBTs are more like a diode, they have a defined forward voltage which is dependant only on the current being passed. This difference allows IGBTs to operate where MOSFETs would be too lossy, at high voltages.

JS

yes you are right js tuffer, and this depend on the characteristic of the type of fet's been used;also i have a pussle which iam trying to solve now,i build my inverter using HI and LO side gate driver and the problem here is when i power the circute with even 36v the wave form at the high side look ok(square wave)but when i power this circute with 48v the wave form at the high side changes from square to strait line -

Added after 9 minutes:

can some one tell me why this wave form change it's normal angle from 180°to about 47°at the high side of the gate and what could be the solution to this problem. thank's.

Hi Kabiru,
You can/should set slowly your 36V up to 48V and check at which potential @what is changed...
K.

Thanks for your quick responce karesz, the wave form start to change it's angle when the potential is above 40v and almost halve of the rail supply will be at the gate of the high side,in this condition the mosfet gate voltage is at saturation point therefore the mosfet is not at the safer side.