ln solar photovoltaic power generation system, DC combiner device should be added between PV module and inverter in order to reduce the connection between PV module and inverter, to facilitate maintenance and to improve reliability for large-scale photovoltaic grid- connected power generation system. The user can combine a certain number of PV modules with the same specifications in series into a PV modules string within the DC voltage range inputted by the inverter, and then connect a number of strings into the photovoltaic combiner box for convergence,then output to the inverter through lightning protective device and circuit breaker, which simplify the system wiring and improve the security of the system.
