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Grid Tie Inverter Schematic 2.0


New Member
when ι design thinking to less consumption in the stimulation of transistors
and the voltage drop at 0,7 v in each diode helps the net stimulation
and diodes in the output transformer prevents
entry instead of exit current would result in higher internal consumption


Most Helpful Member
I for one have never trusted simulation programs to be the least bit correct on these types of circuits.

Try building it ans see what burns up first. Given your circuit layout I suspect the opto couplers with no current limiting resistors will go first. If not the lack of proper zero cross dead band adjustment will likely fry the output transistors if the high switching currents don't smoke the transformer windings first.

Just an educated guess based on personal experimentation done over the years. For basic grid tie power handling circuits simple and robust tends to be most durable! :)


New Member
perhaps the output transformer to heat up a bit
but to be burned should compose the wrong way.
For the rest i have to build it to express an opinion.
if the optomosfet not withstand the stimulation of 2N3055 i will simply
add two 2N2222 to driving it

Thanks for the reply :)


Most Helpful Member
I view GTI design as being a minimalistic concept. low parts count with maximum working efficiency is the goal. Extra parts that serve no practical purpose on the power handling circuits cost money and waste power. Your design has a lot of needless parts and parts with the wrong values as well.

The LM317 voltage regulator is pointless, opto isolators are completely unnecessary, there are 5 diodes that serve no purpose, a number of resistors that are of the wrong values for what purpose they do serve, and if ran at what I would call a realistic working power for a 2N3055 based switching circuit of this design on a 14 volt input I would doubt it would be reliable much above a 150 watt peak working input power with a more than likely return power of less than 100 watts.

I am not sure of your cost for parts but if it was done with all new parts for around $100 and you have a 100w average return on power your theoretical break even run time for 10 cent a KWH electricity would be around 1000 hours running at full output not including power source design and operating costs.


New Member
I see this as the best recycling an old ups.
otherwise the money to give someone on the transformer buy a gti from ebay ready for use.

For the rest i have to build it to express an opinion,
but I think it the best design as a simple construction οf those which have appeared in this thread
-if you have to propose a better then I will not have to say anything else.


New Member
I for one have never trusted simulation programs to be the least bit correct on these types of circuits.

Try building it ans see what burns up first. Given your circuit layout I suspect the opto couplers with no current limiting resistors will go first. If not the lack of proper zero cross dead band adjustment will likely fry the output transistors if the high switching currents don't smoke the transformer windings first.
You 're right on several points and I did some modifications.
Apart from the two diodes in the first transformer..
View attachment 60537


New Member
Thats a very good article love it. Powermos please can you help me out with the schematics circuit design of GRID TIED PV SYSTEM WITH BATTERY BACK.The intented load is 6 volts battery charger.I want to buid and simulate it on Proteus Isis but has been having some difficulties with the the design of the grid tied pv.Will really appreciate if you help out.Thanks alot.


New Member
Hi, I'm a newbie here. Anyone in PEM fuel cell field? I looking at input the fuel cell with 36 to 72 Vdc. Then boost up the low dc to 400 Vdc using a boost converter. After which, using a full bridge inverter to LC filter the signal as rms grid of 220 Vac. I am using the PSIM tool. The desired output is 1 KW and 4A. Comes with MPPT control over the DC input and a unity power control over the AC output.

Please any kind soul can help on this topic.

Thanks a million.


Most Helpful Member
TCM, I love your tenacity!
Well I have been known for getting more than just a few the arm chair safety Nazis and lawyers undies bunched up so tight they cant walk over my showing people how to do this sort of stuff on the cheap and down low DIY level! :D


New Member
Mr. tcmtech

I'd like your help and approval to use its "Grid Tie Inverter Schematic 2.0". I need your help to see if this list of components that put together is sufficient to assemble the circuit on breadboard. If you have the full list and can send me would be very grateful. I have some doubts about the components, which you used in diodes D1, D2, D3 ... 1N4007? What is the relationship that you used in transformers? This right capacitors 2.2m and 2.5m? What you used resistor R5 in the "Control Circuit A"? What voltage Vdd you used in the IR2113? How to calculate L1 and L2?
The list of components that did is this:

Components Model / Value Amount Description
Diode 1N4007 20
Diode Zener 12V MZD12 2
Diode ZR431 1
Diode Zener 3.3V 1N4728A 1
Voltage Regulator LM7812 1
LM555 2
LM2907 1
LM324 1
LM358 1
IR2113 2
Potenciometer 10k 4
50k 2
500k 2
5k 1
Optocoupler MOC3053 1
TRIAC Q7025R5 1 It= 25 A, Vdrm = 700V, Igt=500mA
RESISTOR 3.3 kOhm 2
47 kOhm 3
100 kOhm 3
2.2 kOhm 2
150 Ohm 2
470 Ohm 2
22 kOhm 1
220 kOhm 1
10 kOhm 5
5 kOhm 1
10 Ohm 1
8 Ohm 4
2.5 m 1
10 u 4
470 u 3
100 u 1
100 n 2
1 u 2
35 u 1
2.2 u 2
47 n 1
Transformer 220 / 12 + 12V 1 WITH CENTRAL TAP

I'm trying to simulate the circuit, but not against the IR2113 proteus you have a library with this component? Well that's why I decided to ride it physically. Do you know if this circuit works perfectly?

I'm sorry for my bad english.
Very, Very Thanks!;)
Jean Carlos dos Santos


New Member
Here in Brazil the eletronick electrick registrators used in the new stupid grids are unidirectional.
So, if you produce more energy than you use, you have to pay for the injected energy as it is consumed from you...


New Member
View attachment 67833 This schematic I found on this site http://www.neo-aerodynamic.com/GridTieInverter.html
The writer PHI TRAN has also given the way this is working.
PARTS LIST•4- Alternistors: Part# 511-BTA25-600BW*

•4- Diodes: (at least 600V 0.1A). To make sure all parts are approved and UL certified we use a couple of Bridge Rectifiers part#512-GBPC1506*
•1- Large capacitor or capacitor bank: We use 2 400V 5 UF.

•Some heavy gauge wire and quick connector (from local hardware/electrical store

•1- piece of 6" x 8" aluminum plate as heat sink.
•2 fuse holders and 220V 30Amp fuses*. (4 fuses are better)

•Terminal block for DC and AC 110V wall plug/receptacle.
•Some screws, small bolts, and nuts.
•Even its back side looked complex but it is exactly the same as the schematic above. It's front is much clearer and simpler.
•The rated wattage of the device are defined by the ohm law W=V *I, in this case it the alternistors are rated at 600V and 25Amp; assuming that the the capacitor(s) is large enough.
•Warning: This system could drain a car battery in a few minutes.
We first use a Variac to try on low AC voltage of about 24V. Only when we are comfort with the system then you connect to the grid.

* The parts are selected because we have some extra and handy.


•On the schematic the symbol of the triac does not state pin T1,T2 or MT2, MT2 but pins the actual work does make the difference. All the MT2 pins are connect to the AC source as at the schematic.
•DC supply can be anywhere from 3-50V
•At times we place 4 fuses after MT1 pins even though in our tests it only blew one when we abuse.
•You may need to try on different capacitor sizes to select the one that fit your configuration.
•As it; most household breakers; 10A ,15A, 20A; may not be strong enough to sustain the uploading and strip.


•Wide range of DC voltage from 3->50V.
•Always in phase/synchronous to the grid.
•The system automatically turns to idle (inactive) when AC the power goes down
•Instead of using over imposing technology which represent creation of higher voltage and synchronous AC, the technology use the amplification technique which always eliminate the islanding problem.

•No CPU (eliminate software, firmware problem)
•Only use passive components.
•Theoretically, the design has 100% efficiency. The only lost is the heat (equivalent to a 3w night light bulb?)

Disadvantages: (of this built)

•Fuse blow if the DC voltage raise above 50V.
•Only works on 110V AC configuration of 1 hot and one ground (US common residential electric system).
•Fuse blow in 2 hot wire AC configuration.
•Power surge may cause fuse blown.

Some notes about the technology.

•The old method of building a grid tie inverter is to creating an AC current that has higher the amplitude but having the synchronous frequency with the grid. The the two are parallel connected as if we seen in the battery charger.
•If one traces or simulates the current it is exactly as if it is a charger to be used to charge a battery bank that contains 8 serially connected batteries. It can be used exactly as it (if the polarity is reversed).
•And the circuitry (of that battery charger) works as (grid tie) inverter when it allows the reverse procedure to happen when it use the switching mechanism to produce a DC instead of using the blocking the reverse current as if it is in the conventional type of battery charger. Therefore the capacity of the device is limited by the rated of the component in AMP and the capacity of the capacitor bank.

•The technology that we work here lie behind a new approach:
•First it converts the AC current to the DC not by blocking the reverse bias as of the diode but switching the polarity of the current every time it crosses zero as if one turns a DPDT switch 120 times per second.
•Secondly; The system now provides the conversion in both directions. AC->DC and DC->AC. The rest of the work is to add some voltage at the DC side at the same time to expose it to a brake to remove unwanted power spikes.

•The novelties are:
◦One does not need to worry about the AC frequency.
◦Because it use switching mechanism to achieve the DC then both the AC and DC side interact each others. Uploading power to the grid is a simple job of raising the amplitude at the DC side. It's simple.
•Such the technology? simple? anyone can do it? Why nobody has ever attempted before? -Perhaps it's not obvious at the first glance. This is just a fall through from other projects; our intention at the time was not to develop a GTI (grid tie inverter). If is is our main ficus then definitely; this approach is not among the options.

Grid connection & UL Standard issues:

UL Issue:
UL 1741 is the de facto standard for grid tie inverter. and it's not applicable to this type of grid tie inverter.

The UL standard applies to grid tie inverter as if it is an independent AC power plan with: Allowable tolerance of the power curve, when it is safe to upload, etc . . .

This type of grid tie inverter is not an independent power plan and nor it generates power curve, nor it has the capability to be islanding.

This type of grid tie inverter contains only passive components reacting according the change from the grid and does not inject any current into it.

Grid connection:

For many decades each and every individual component has been approved and certified to be connected to the grid. Their manufactures spent millions for that purposes.

It's just happened on the way how to wire them making it to function as a grid tie inverter. I don't know how one can forbid user to use the products that they approved and certified. The same way one goes to the local store buying timer, sensor, charger, etc . . . .

In the nutshell, the system also is a functional battery charger, when battery bank of 8 serial unit is working in both direction. Such AC->DC converter; 'battery charger' only allows user to reverse its procedure to (grid tie) inverter by switching the battery polarity.

Beside nothing like this has been done before; honestly no one knows how to deal with it.

Personal I think the power companies may be able to stretch their arm on new installation (grand father clause?)- Or they can pass the law to restrict the sale of those components . . . . .
Here are the photosView attachment 67834View attachment 67835View attachment 67836View attachment 67837View attachment 67838View attachment 67839

Please any comments as to how this works and has anyone tried this kind of circuit before?


New Member
Hi Plodhi

It seams me a realy fantastic grid tie inverter.
I go to buy today the components.
The secret seams me to be the capacitor in serie...
So it is possible to feed 5VDC in 220VAC at every begining of the senoid.


New Member
Grid tie inverter

Hi Plodhi

It seams me a realy fantastic grid tie inverter.
I go to buy today the components.
The secret seams me to be the capacitor in serie...
So it is possible to feed 5VDC in 220VAC at every begining of the senoid.
Great! Lets see if it works on the 220V system having LINE->NEUTRAL like in many European and Asian countries. By the way did you browse that site there were other 'unconventional' type of circuits there too. :confused:


Well-Known Member
Not sure how that schematic is supposed be a grid tie inverter.

edit: nearly everything on that website is rubbish. Perhaps the clean your toilet rim project might work.
Last edited:


New Member
Yes, they are many other schematics and projects at that site.
Realy much of the things are not realistic and much optimistic, but not at all.
I believe that the schematics to connect a assyncronous motor as a generator with low RPM has also a chance to run, and if some clean head substitute the doble relays with triacs, resistors, capacitors and scrs, that circuit may be also a great project.

To the GTI, I think it is good to ad a simple diode in the DC line, and perhaps more litle and simple things.
The basic idea is very brilliant, simple, great, like to put a disc to make a wheel... and than put the rubber...
A 1 kW GTI realy has not to be senoidal. The arguments from the knowing anything spetialists, are all to much fool.

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