What causes small leakage currents in photovoltaic (PV) modules?

ABSTRACT: Small leakage currents flow between the frame and the active cell matrix in photovoltaic (PV) modules under normal operation conditions due to the not negligible electric conductivity of the module build-ing materials.

How do leakage currents affect PV module efficiency?

This will induce leakage currents flowing through the module package potentially leading to significant PV module efficiency loss. In standard p-type c-Si PV modules, leakage currents can flow from the module frame to the solar cells along several different pathways (Fig. 2), which are depicted as follows:12,13,44,48–50

How does dust affect the leakage current of a PV module?

A slight amount of dust (2 g/m2) on the module surface was found to trigger the wet leakage current to a considerable limit. Tiny dust particles have a capability to attach with some ionic compounds, where Na ions are dominant from the coastal area that prompts the leakage current of the PV module.

How to eliminate leakage current in solar PV array system?

There are two distinct methods to eliminate the leakage current in the solar PV array system: (i) obstruct the leakage current, (ii) reduce the variation/constant common-mode voltage. The additional diodes/switches are incorporated in the system to obstruct the leakage current by disconnecting the PV array from the grid side network.

Why are photovoltaic modules exposed to high voltage?

The photovoltaic (PV) modules are in PV arrays normally connected in series and thus some of them exposed to high system voltages since frames of the PV modules are grounded.

Does surface temperature affect high-voltage-stress leakage current of crystalline PV module?

Effects of different parameters such as module surface temperature, surface wetting, salt and dust accumulation, and aging condition on high-voltage-stress (HVS) leakage current of the crystalline PV module are investigated in the laboratory.