Meanwhile, each power converting apparatus 500 in a plurality of photovoltaic modules 50a, 50b, . . . , 50n includes an unfolding inverter 540, as described above with reference to FIG. 1A, and, based on a difference between a grid voltage Vacr and an output current of the inverter 540, the controller 550 controls a bidirectional current to flow to the converter 530. Accordingly, the power converting apparatus 500 including the unfolding inverter 540 may be capable of controlling a power factor. As a result, it is possible to output AC power stably in connection with the grid.

FIG. 2 is a front view of the photovoltaic module according to an embodiment of the present invention and FIG. 3 is a rear view of the photovoltaic module of FIG. 2.

Referring to the figures, the photovoltaic module 50 according to an embodiment of the present invention can include the solar cell module 100 and the junction box 200 provided on the rear side of the solar cell module 100.

The junction box 200 can include at least one bypass diode for preventing a hot spot in the case of occurrence of a shading.

FIG. 4 shows that a junction box includes three bypass diodes Da, Db and Dc corresponding to four solar cell strings of FIG. 2.

Meanwhile, the junction box 200 can convert DC power supplied from the solar cell module 100. This will be described with reference to FIG. 4 and the following figures.