PV generators do often contain low voltage bypass diodes at module level, and less frequent high voltage string blocking diodes. Example of such blocking diodes are the Ixys DNA30E2200P (VRRM = 2200V) and DSI30-16A (VRRM = 1600V).
String blocking diodes
These string blocking diodes normally operate in forwarding mode, thus at a higher junction temperature. Let's say forwarding 2,3 Amps at NOCT. NOCT is irradiance 800 W/m², ambient temperature 20ºC, wind 1 m/s.
PCB assembly with heat sink
String blocking diodes are often soldered on a PCB and mounted with heat conducting material onto an aluminum heat sink.
Failure rate
Can someone point me to authoritative source availble for failure rates of high voltage (VRRM > 1500 V) diodes that are used as string blocking diodes in a photovoltaic generator setup, and where the DUT are manufactured 2007 or later?
