1500V solar inverter PID

How can PID be prevented in a galvanically isolating inverter?

In PV plants with galvanically isolating inverters, PID can be prevented reliably by earthing the negative pole of the PV array, as this shifts the potential of the entire PV array to the positive.

What is a PID in a PV panel?

The PID is the abbreviation of the ‘’Potential Induced Degradation’’, which occurs in the semiconductor materials of the PV panel and affects their performance. Each crystalline PV panel connected in series, form a string, which can be connected to a transformerless inverter.

Why is PID a degradation mechanism in high-voltage PV systems?

PID is a degradation mechanism occurring in high-voltage PV systems because of a large poten-tial relative to ground, and is depend-ent on the magnitude and polarity of the system. The trend in recent years towards 1000–1500V systems increases the susceptibility of PV modules to PID, as a consequence of the high electric potential.

How to reverse PID in a transformerless inverter?

Companies such as SMA have developed the PV ofset box , which reverses the efect of PID in systems using transformerless inverters. If a voltage of the opposite polarity to that of the system is applied, which can be done by connecting an ofset box in parallel to the inverter, the modules will almost completely recover from PID.