What is frame and divider conductance?

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Yes, this is essentially the same as U-value. This is the conduction heat transfer per area of window frame or divider that is projected onto the same plane as the window itself. The heat transfer equation used by EnergyPlus is:

$Q_{cond} = k*A_f * (T_{frame, inside} - T_{frame, outside})$

Where $k$ is the frame conductance input you are asking about. This equation also applies to the window divider conductance input.

You can read more about window frame and divider heat transfer calculations used by EnergyPlus here, as well as refer to this other Unmet Hours post that has a good discussion about this topic.

Just to correct the previous answer. Frame Conductance is different from U-value in that it does not include air film.

For example, the U-value of Aluminum Frame in the library of Berkeley Lab WINDOW Program is 5.680 [W/m2·K].

The Frame Conductance of this Aluminum Frame can be hand-calculated as follows.

Frame Conductance = 1 / {(1/Frame Conductance) - (R-value of outdoor air film) - (R-value of indoor air film)}

R-values of Air Film which are used in EnergyPlus are as follows.

All exterior conditions                       0.0299387 [m2·K/W]
Interior vertical surfaces                    0.1197548 [m2·K/W]

Then, the calculation above is

Frame Conductance = 1 / (1/5.68 - 0.0299387 - 0.1197548) = 37.9321831 [W/m2·K]

It's quite different from the U-value of 5.680 [W/m2·K].

Alternatively, some users recommend exporting IDF files which include Frame Conductance by the WINDOW Program. The exported Frame Conductance of the Aluminum Frame above is 56.42384 [W/m2·K], which is different from the hand-calculation above because WINDOW Program uses different air film resistances to EergyPlus.

All exterior conditions                       1/30 = 0.033333333 [m2·K/W]
Interior surfaces                             1/8 = 0.125 [m2·K/W]

Frame Conductance exported by the WINDOW Program = 1 / (1/5.68 - 0.033333333 - 0.125) = 56.42384 [W/m2·K]

In this case, 56.42384 [W/m2·K] seems more appropriate as the U-value of Aluminum Frame (5.680 [W/m2·K]) is from the WINDOW Program and it should be based on the air film resistances used in the WINDOW Program. When we get U-value data of window frames, we should be careful what air film resistances are based on.