On Apr 14, 10:20*am, Home Guy wrote:
...
At night the substation voltage ranged between 0.4 V to 0.7 V higher
than the home voltage. This is representative of a typical circuit with
voltage drops through the line and transformer impedances. During
daylight hours, this reversed and the home voltage rose as high as 0.7
V, or 0.6%, greater than the substation voltage. ...

Currently, there are too many uncertainties on the circuit to perform
any meaningful whole system validation. Efforts are under way to
increase the monitoring on the system so that the overall model may be
better validated. This includes adding meters at critical points to
eliminate many of the unknown loads described above.

They have stated that the servo-loop stability of grid voltage
regulation -may- become questionable at over 20% uncontrolled solar
input.

http://eioc.pnnl.gov/research/gridstability.stm

jsw