Grid Tie Inverter Project - Page 7

 you wrote:

That same law is also preventing you from providing anything useful.
Take off the lead helmet. You have electrons that are trapped inside
that thick skull of yours.

Jim Rojas

  On 12/22/2010 11:58 AM, Jim Rojas wrote:

<snip>

*IF* the 110V version 'works', then consider this:

Because the upper and lower circuit are connected to each 110V supply as
they are, the positive peak on L1 (with respect to the N of the upper
ckt) occurs at the same moment that the N of the lower circuit is also
positive (with respect to L2).

So when the Q2 of the upper ckt is conducting, so is the Q2 of the lower
ckt.  That connects L1 of the upper ckt to the N of the lower ckt.
Similarly, when Q3 is conducting in the upper ckt, so is Q3 of the lower
ckt, connecting the N of the upper ckt with L2 of the lower ckt.

Finally, remember that N of the upper ckt is connected to the same
neutral bus in the service panel as the N of the lower ckt.  So when
both Q3's are conducting you have a direct short from L2 to N and when
the two Q2's are both conducting, you have a direct short from L1 to N.
  Fuses F2 and/or F3 will blow when this occurs.

Rather than trying to get two 110V ckts working side by side (with no
isolation between them), it would be easier to get one 220V ckt working.

But as some others have pointed out, I think you need a lot more than
what you've shown here to have a useful grid-tie inverter.

daestrom

 daestrom wrote:

Thank you for your input. It is great appreciated.

Jim Rojas

 Tell him where an AAA cell can co0gen feed the HV line to his house.


On 12/22/2010 11:58 AM, Jim Rojas wrote:
*IF* the 110V version 'works', then consider this:

Because the upper and lower circuit are connected to each 110V supply as
they are, the positive peak on L1 (with respect to the N of the upper
ckt) occurs at the same moment that the N of the lower circuit is also
positive (with respect to L2).

So when the Q2 of the upper ckt is conducting, so is the Q2 of the lower
ckt.  That connects L1 of the upper ckt to the N of the lower ckt.
Similarly, when Q3 is conducting in the upper ckt, so is Q3 of the lower
ckt, connecting the N of the upper ckt with L2 of the lower ckt.

Finally, remember that N of the upper ckt is connected to the same
neutral bus in the service panel as the N of the lower ckt.  So when
both Q3's are conducting you have a direct short from L2 to N and when
the two Q2's are both conducting, you have a direct short from L1 to N.
  Fuses F2 and/or F3 will blow when this occurs.

Rather than trying to get two 110V ckts working side by side (with no
isolation between them), it would be easier to get one 220V ckt working.

But as some others have pointed out, I think you need a lot more than
what you've shown here to have a useful grid-tie inverter.

daestrom

 Josepi wrote:

Here is the link of the designer of the GTI circuit.

http://www.neo-aerodynamic.com/GridTieInverter.html

There is a complete parts list there in case you would like to make one
for yourself. It's easy to knock down these ideas, but it's always
better when you first try it yourself, then help develop the idea for
all to use.

Jim Rojas