What is BS EN 62979- Thermal runaway test for bypass diodes about?
BS EN 62979 provides a method for evaluating whether a bypass diode as mounted in the module is susceptible to thermal runaway or if there is sufficient cooling for it to survive the transition from forward bias operation to reverse bias operation without overheating.
This test methodology is particularly suited for testing of Schottky barrier diodes, which have the characteristic of increasing leakage current as a function of reverse bias voltage at high temperature, making them more susceptible to thermal runaway.
The test specimens which employ P/N diodes as bypass diodes are exempted from the thermal runaway test required herein, because the capability of P/N diodes to withstand the reverse bias is sufficiently high.
Who is BS EN 62979- Thermal runaway test for bypass diodes for?
BS EN 62979 on bypass diodes is useful for:
- Photovoltaic module manufacturers
- Bypass diode manufacturers
- Photovoltaic power system manufacturers
- Solar cells and solar panel manufacturers
- Entities involved with solar energy engineering
- Aerospace and automotive industry
Why should you use BS EN 62979-Bypass diode photovoltaic modules?
Bypass diodes are placed in reverse bias between the positive and negative output terminals of a photovoltaic cell or panel and have no effect on its output. However, in some cases, increasing temperatures and reverse bias leakage current make the bypass diode susceptible to breakdown, the phenomena of which, is also known as ‘thermal runaway’. In this regard, BS EN 62979 provides the thermal design of the bypass diode in the junction box such that that thermal runaway does not occur.
The guidance in BS EN 62979 can assist you in evaluating whether the bypass diode as placed in the module is experiencing thermal runaway or whether there is adequate cooling for it to survive the transition from forwarding bias operation to reverse bias operation without overheating.
BS EN 62979 can thus help eliminate the effect of partial shading on photovoltaic modules and protect the shaded cells for uninterrupted performance.
