Repairing ribbon bus bar interruptions in photovoltaic modules using non-intrusive interruption location

Abstract

Ribbon bus bar interruptions in photovoltaic modules represent approximately a 10 % of photovoltaic module failures. The purpose of the present work is to repair this failures using the simplest, fastest and cheapest techniques. Twin and single intercell interruptions are defined. The first one, twin intercell interruptions, cut off electrical current flow between two cells while the second one permits current flow between cells through just one ribbon bus bar at the cost of module efficiency reduction. We propose non-intrusive methods to find precise location of single and twin intercell interruptions. A simple technique for intercell interruption repairing is described. Three modules were repaired, multiplying its power production in two cases by 4, when comparing with its non-repaired power production. The third module did not produce any electricity before repairing, and after being repaired produced a power similar to its nominal value. The proposal of repairing can be put into practice in modestly equipped factories and laboratories, without using expensive and time consuming techniques.