LabVIEW

synchronization phases

Hi @ all!

I use a PI controller for the synchronisation to the bulk grid. I could solved the problems with the voltage and frequency. But still I have the problem with the phases of the grid. The main problem is, that the 1st phases (public grid=master) is also a dynamic system ( it rotates around) and I can´t tracking the 2nd phases (island grid) on the 1st one:(

I wrote a PI Controller in a formula node and it works very well with the Voltage and frequency. I use it for the control of the active and reactive power of my Island Grid Mode. But I have to synchronize also the phases with the Grid for reconnection with the public Grid.I use a PXI Embedded Controller PXI-8186, a Data Acquisition Card PXI-6071E and a Digital I/O Card PXI-6528. I don´t know why the phases are rotating, so I can´t set the active power for my island grid.

Normally I would check the phases and than the frequency and send it, to my inverter to handle the active power and reactive power by the current.

But with the phase angle I have the problem. They switch between from -360 till 360° (it is 0°), but I have a phase jump in my controller output.

I tryed to set the angle of the Grid constant but it doesn´t work with the block in LabVIEW "Metering frequnecy components" ...it is already a dynamic system:(

Can anybody give me an advice?

So Thanks for support

Best Regards

Holger