A simple yet useful Microprocessor based Arduino full-bridge inverter circuit can be built by programming an Arduino board with SPWM and by integrating a few mosfets with in H-bridge topology, I have explained the details below:
In one of our earlier articles I will comprehensively explained how to build a simple Arduino sine wave inverter, here we will see how the same Arduino project could be applied for building a simple full bridge or an H-bridge inverter circuit.
Using P-Channel and N-Channel Mosfets
To keep things simple we will use the P-channel mosfets for the high side mosfets and N-channel mosfets for the low side mosfets, this will allow us to avoid the complex bootstrap stage and enable direct integration of the Arduino signal with the mosfets.
Usually N-channel mosfets are employed while designing full bridge based inverters, which ensures the most ideal current switching across the mosfets and the load, and ensures a much safer working conditions for the mosfets.
However when a combination of and p and n channel mosfets are used, the risk of a shoot through and other similar factors across the mosfets becomes a serious issue.
Having said that, if the transition phases are appropriately safeguarded with a small dead time, the switching can be perhaps made as safe as possible and blowing of the mosfets could be avoided.
In this design I have specifically used Schmidt trigger NAND gates using IC 4093 which ensures that the switching across the two channels are crisp, and it's not affected by any kind of spurious transients or low signal disturbance.
Gates N1-N4 Logic Operation
When Pin 9 is logic 1, and pin 8 is logic 0
- N1 output is 0, Top Left p-MOSFET is ON, N2 output is 1, the Lower Right n-MOSFET is ON.
- N3 output is 1, Top Right p-MOSFET is OFF, N4 output 0, Lower Left n-MOSFET is OFF.
- The exactly same sequence happens for the other diagonally connected MOSFETs, when pin 9 is logic 0, and pin 8 is logic 1
How it Works
As shown in the above figure, the working of this Arduino based full bridge sinewave inverter can be understood with the help of the following points:
The Arduino is programmed to genearte appropriately formatted SPWM outputs from pin#8 and pin#9.
While one of the pins is generating the SPWMs, the complementary pin is held low.
The respective outputs from the above mentioned pinouts are processed through Schmidt trigger NAND gates (N1---N4) from the IC 4093. The gates are all arranged as inverters with a Schmidt response, and fed to the relevant mosfets of the full bridge driver network.
While pin#9 generates the SPWMs, N1 inverts the SPWMs and ensures the relevant high side mosfets responds and conducts to the high logics of the SPWM, and N2 ensures the low side N-channel mosfet does the same.
During this time pin#8 is held at logic zero (inactive), which is appropriately interpreted by N3 N4 to ensure that the other complementary mosfet pair of the H-bridge remains completely switched OFF.
The above criteria is identically repeated when the SPWM generation transits to the pin#8 from pin#9, and the set conditions are continuously repeated across the Arduino pinouts and the full bridge mosfet pairs.
Battery Specifications
The battery specification selected for the given Arduino full bridge sinewave inverter circuit is 24V/100Ah, however any other desired specification could be selected for the battery as per the user preference.
The transforer primary voltage specs should be slightly lower than the battery voltage to ensure that the SPWM RMS proportionately creates around 220V to 240V at the secondary of the transformer.
The Entire Program Code is Provided in the following article:
4093 IC pinouts
IRF540 pinout Detail (IRF9540 will also have the same pinout config)
An Easier Full-Bridge Alternative
The figure below shows an alternate H-bridge design using P and N channel MOSFETs, which does not depend on ICs, instead uses ordinary BJTs as drivers for isolating the MOSFETs.
The alternate clock signals are supplied from the Arduino board, while the positive and negative outputs from the above circuit is supplied to the Arduino DC input.
Questions & Answers
thanks Swag for the update and correction in diagram i’v tried the simulation with TL494 an the input cd4093 and it works fine as a modified sine so am gonna build this and see sine i like h-bridge more than centered type.
pics attached
http://www.mediafire.com/?96fb9vdahpidh
Thank you very much Nito, I hope you succeed with your project, but remember TL494 is specified to work with minimum 1000 Hz so it might not work correctly below this frequency
Thanks once more for the info. Will SG3525 be okay if i use, from the data sheet it’s frequency is 100 Hz to 400 kHz and i already have one circuit built as well as the TL494.
am yet to get 4093 ic to test the whole project
yes SG3525 will be OK, alternatively IC 4047 can be even better
Hi Swag, do I have to bridge the paired inputs on the 4093, Ie Pin’s 1 & 2; 5 & 6 etc?
Regards D
Hi Dylan, yes the inputs of all the gates will need to be shorted.
Thank you Sir!
I built it this morning: https://imgur.com/a/xrMajrw
Will connect it up tonight after I get home from work
That’s great Dylan, I wish you all the best, just make sure the mosfets are correctly connected before you apply power….
Hi Swag, I built the system and it seems to be working. I used a 12V power supply boosted up to 24V in place of the batteries and I was able to get an AC reading on both sides of the transformer. The problem is I am only getting 4V there. Is this because of the power supply?
Thanks again for taking the time to help me out 🙂
Hi Dylan, yes it could be due to power supply, however the secondary should have shown higher voltage if both side mosfets are conducting correctly.
you can confirm the design with a 12V transformer and 12V power supply and check the response. Once confirmed you could then go ahead with 24V
Hi Swagatham , you blew my mind, I have a couple of none center tapped trafo`s from damaged driver inverters ranging from 24V, 36V , always love full bridge , I will try 24V , then 36V for 48V input output 240VAC
Thanks again
You are most welcome vhafuwi, keep up the good work.
Hello Swagatham , what is the alternative to IC4093
Hi vhafuwi, you can try IC4584B, and use 4 out of 6 available gates, and terminate the inputs of the unused 3 gate appropriately
Thanks for the prompt reply , Due to the simplicity of the circuit , I am constructing after testing I will design the PCB layout and order few boards ,
One question Though
For the SPWM output , what will be more efficient comparing Aduino Atmega328P / IC4047 /SG3525 , I have been considering IC4047 for its straight forward use ,
Any Idea how to get Puse Sine Wave out of IC4047 to feed in the above circuit.
Trying to get this circuit cheaper and efficient as possible
4047, 3525 cannot be used directly for creating SPWM, you may have to apply an external SPWM chopper to enable sine waveform from these ICs.
If Atmega is coded with SPWM just like the Arduino, then it might also work as effectively as the Arduino.
for 4047 yo can refer to the following post
https://www.homemade-circuits.com/pure-sine-wave-inverter-circuit-using/
Thanks Swag, I have a question, why you use or for what is use the IC 4047 in this circuit, I am a noob on electronics and I would like to know more about the IC 4047
Hi Ethan, IC 4047 is an oscillator IC, which has two outputs for generating a frequency with alternate ON/OFF switching, meaning when one of the two outputs is ON the other will be OFF and vice versa, the oscillation rate depends on the adjustment of an external resistor/capacitor values connected with another set of pinouts of the IC
Ok thanks, and I have a big question, what pin are conectted to which mosfet, can you explaine me, for example “pin 12 its conected to IRF9540”, like I said im a noob on this
The mosfet gates are connected to the NAND gates from the IC 4093, you can see the IC pinout diagram at the bottom section of the article, you can see which pins are internally connected with its internal NAND gates. Just compare the IC layout with the gates shown in between the Arduino board and the mosfets, you will get an idea how the IC 4093 needs to be configured
Sir is there any programming code require for this circuit
link for the code is given in the article, please check it.
Sir we realy appreciate with ur effort. please sir can u help me with pure sine wave inverter circuit using ATMEGA32 IC that include LCD DISPLAY
Hi Bashir, I do not have this design at the moment, if I happen to find it I’ll let you know…
thank u sir
Sir how r u? I have a duestion
we know sine wave inverter hard to design,
so what kind inverters are best for our normal house hold appliances? ( light, fan only)
Modified sine wave or PWM what is best?
Hi Mehedi, both will work, PWM inverter is also a kind of modified inverter but they are better than ordinary modified ones. If you apply proper filter stage at the transformer outputs both versions will work quite efficiently.
sir how are u? i have a question. In your 4093 ic logic, when pin 9 give pulse (=1). N1 = 0 and N2 = 0, so P channel (N1) = OFF and N channel (N2) = ON. Is it right? thanks
I am good Luna, thanks, When N1 input is high, its output is 0, this 0 is applied to the input of N2 causing its output to be “1” or high, this allows the opposite diagonally positioned fets to conduct simultaneously and keep the other diagonal fets switched OFF.
Oh thanks sir. GBU
You are welcome!
Thanks alot swag……can you mention? What ic and voltage regulator should i prefer when constructing same design for 45v dc supply…….
Hi Raghib, the easiest way is to use a transistor emitter follower regulator. Please see how the BC546 circuit is in the following article, for getting 9V
https://www.homemade-circuits.com/48-v-inverter-circuit/
Will it work i have input supply from 45v dc solar panel rating 300W to get a spwm unipolar based inverter (230v ac, 50Hz)where losses is minimum.How can i do please suggest me.Can i go for your full bridge inverter?How can i fixed ic and regulartor for 45dc input voltages.
Yes the mentioned emitter follower BC546 concept will work for 45V DC input. The base zener will fix the output voltage. The above Arduino is a bit complex so i wouldn’t recommend this to you since you are a newbie. Instead you can use your own unipolar design without issues.
Thanks swag……Will ic4093(maximum rating 18v) not burn?if we supply 24v dc.
It will definitely burn even at 20V, a 7812 IC can be used for preventing this issue.
Reply.
The mosfets were connected the wrong way and after fixing that we got the pwm pulses.
Thank you for your kind cooperation.
That’s great Vignesh, let me know if you have any further issues with the design
Please sir can u help me with cascaded H-Bridge 5 level inverter circuit using arduino
Hi Dhams,
I’ll investigate, and If it’s possible, I will surely try to update it.
Hello sir,
We tried to build the circuit as shown on the breadboard,but unable to get the output as spwm. Can you suggest what probable mistakes we might have made.
Hello Vignesh,
What kind of output are you getting? I have not yet tested this circuit practically but I believe if it’s built correctly it will surely work.
But on breadboard the mosfet may have a high possibility of blowing even with minor hidden issues
Hi Swag!
Did you test this circuit, with Arduino code, IC4093 and MOSFETS in bridge? is it necessary to use both, so P-channel and N-channel? If I understand right, P-channel and N-channel is here because of transition, when the first 10ms period ends and second 10ms period starts, so that transition between periods is not dangerous for MOSFETS? If I use delay and use relay on +12V line, then I could use just N-channels? Will be 9V/230V transformer ok for 12V battery, we calculated the rms value of 12V to 8,5V rms with Arduino signal, so it could be ok?
Thanks for answer, Serđ.
Hi Serd, As per the standard transistor biasing rules the source or the emitter must get the “ground” reference for operating through a normal base/gate switching.
That’s why p-channel is used on top and n-channel on bottom so that p gets the required positive “ground” reference and the n gets the negative “ground” reference.
If all 4 n-channel fets are used then the situation gets complex and requires bootstrapping a explained here:
https://www.homemade-circuits.com/h-bridge-bootstrapping/
The p channel n channel will also work but the p channel might show some significant heating due to incompatibility with n channel switching and higher R(ds) than n-channel.
The transition is perhaps handled correctly here, with the help of a “LOW” between the Arduino code sets, and also by the use of Schmidt trigger NAND gates IC 4093.
I have not yet tested this design practically!!
Thanks for your answer. So I don`t have to change Arduino code, because there is “LOW” command for signal, at the end of first and second period. Now I understand better, why to use P-channel at top and N-channel at bottom.
That’s right Serd, Glad it helped!
I will use 9V/230V – 200W or 300W transformer with 12V car battery. If I use 200W or 300W, I can expect the primary current of: 200W or 300W / 9V= 22A or 33A. Let`s say that I use 300W, that mean current consumption of max. 33A on battery side.
N channel IRF540 datasheet is (100V and 33A) and P-channel IRF9540 (100V and 19A). Are max. current limits of MOSFETS added together, so 33A+19A= 52A? Or is better to use N-channel IRF3205 (55V and 110A) and P-channel IRF9540 (55V and 74A) with that power of transformer?
The 33A will be the maximum current delivering capacity of the transformer, but actually 33A will be consumed only when the load is 33 amp, so it will depend on the load.
Current will not add across the mosfets, it will be 33A only, so both the mosfets can be rated at around 40A, higher values than this will also do.
Yes the last two mosfets look good and can be used.
So, if I understand right, the current in that schematic is limited to 19A, because the P-channel IRF 9540 MOSFET has 19A max. current limit, this means about 200W with 9V transformer? It doesn`t matter, if IRF540 has higher current limit, max. current of IRF 9540 is 19A, so 19A is max. current through. The current limits for both MOSFETS should be closely together. Let me know, if I`m right.