An Electroluminescence (EL) test organized by the customer brought certainty that a major part of the modules is influenced by PID. To be able to evaluate the recovery process measurements have been performed with 8 string packages beforehand. Because the plant is equipped with string inverters PADCON Float Controller SI for String Inverters have been installed. The Float Controller SI is desigend for the specific use with String Inverters and is able to supply up to 3 MPPT’s with a total of max. 110 kW. After a test period of 50 days the comparison measurments show astonishing improvements of up to 12,7% of the output of the string packages.

The graphic demonstrates the recovery process based on the output of the string package:

First, we equipped only a part of the plant with PADCON Float Controller, for testing purposes.
Since the inverter has 5 individual performance parts, we installed addition to the PADCON Float Controller CI, a Multi Connector, to supply all the power units / MPPT.

In addition to the comparison measurements at each string package, we observed the recovery development of the photovoltaic plant on the monitoring system. Through connecting the Float Controller with the monitoring system, we could easily supervised the individual parameters and the operation of the device. In this test installation, is in addition to the enormous recovery rate, positive to watch, that the individual string packages returned within the test period to the same proficiency of performance (PR), although they were different affected with PID, too test launch.

Following the announcement of the test results, the entire system was equipped with PADCON Float Controllers and performed since then at a high level (> 83% PR)..

The graphic demonstrates the recovery process based on the PR-performance:

EL recordings of our customer demonstrate us, that certainty the majority of the modules are affected with PID. In order to assess the trend of the recovery process, power measurements and EL test were carried out on 50 pcs. PV modules before the test installation. Since the Plant is equipped with string inverters, therefore we used PADCON Float Controller SI. This specially designed string inverter, can supply up to a total of 3 MPPT / max. 110kW. After the test period of 4 month, the measurements revealed a amazing improvements of up to 23.4% of the PV modules output.

The graphic demonstrates the recovery process based on the output of 3 pcs. PV modules:

PID was identified through I-V Curve Measurements that showed performance losses up to 14% and was validated through thermographic pictures.
The PADCON Float Controller CI 70 was installed on one of the central inverters to show the performance increase potential and the achievable module recovery.
After a period of 4 months, the measurements showed up improvement of up to 14 % of the string packages output and an improvement up to 46% on certain modules level.

The graphic demonstrates the recovery process based on the output of the string package: