Transfer Power from Customer to the Grid 1

[ahmelsayed]

hi,
In our power Distribution System, the power transfer from central station to step-up transformer to substation and for our home use it transfer to a step-down transformer then supplied to our homes
The if one of the customer want to opposite the direction of power
to be from his home (his special generaor,solar cells, hydro car,..)
here is the question :
How can The Customer do That(supply the Grid) without affect the main power ??

 

[davidbeach]

Just think of it as negative load.

 

[pwrengrds]

synchronize with the grid before back feeding. This does require permission from the grid operator to do this as well as some equipment that is able to synchronize with the grid and automatically separate. In short though, yes it is commonly done.

 

[ahmelsayed]

I already know about synchronization with the power station but My Problem is how to Transfer my power to the Grid and Considering it as a negative Load will not affect on the Grid or on my power sources(generators, Solar cells, .. )??

 

[davidbeach]

What affects do you think there will be? I'm assuming a small distributed source and a large grid; the only thing you'll see is slightly less load.

 

[dpc]

Ask yourself how the direction of power flow is determined in an ac system.



David Castor

http://www.cvoes.com

 

[waross]

If you are using a generator, the throttle is opened automatically by the governor according to the various settings of the governor.
This puts the generator a small fraction of a cycle ahead of the grid and power is supplied back to the grid. An inverter must advance its wave form slightly ahead of the grid in order to transfer power to the grid.
Your utility will have rules for the protection required before they will grant permission to export power.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[slavag]

Hi.
ahmelsayed, as Bill saied, your utility have rules for work with DG-distributed generation.
any step-down transformer work as step-up transformer, w/o problem.

You must think about decoupling/anty-islanding automation/protection.

 

[ahmelsayed]

OK, I'm actually a control Engineering student and it seems that there are somethings in the power part i don't know about
but from the above replies i got some points I'll search about and back.
If can suggest more points in this topic to search about ??

 

[MAS2000]

Most of the friends above already explained the process, however to simplify I will add that power flow in any power system depends upon:

1. Frequency
2. Voltage
3. Power Factor

Controlling these parameters we control power flow in power system.

Usually in distribution system, power reversal is rare (only under extremely low load conditions and) therefore the distributed generation synchronize to grid will help reduce the real power flow from the main grid or substation towards load centre.

M.A.Sh.
Elect. Engr.

 

[waross]

Frequency is locked together.
Power transfer depends on slight changes in phase angle. Voltage and power factor go sideways. They affect reactive power which is at right angles to real power and has little effect on power transfer. (Except for reactive power transfer.)

Bill
--------------------
"Why not the best?"
Jimmy Carter