According to latest IEA (International Agency Report) Report, Snapshot of Global PV Markets 2016, Italy, where PV production cover 8% of electricity needs, is the country with the highest solar contribution to electricity demand in Europe, followed by Greece (7,4%) and Germany (7,1%).
This is enough to confirm that revamping is a strategical issue for PV Inverter producers, like Omron, which are still on the market and should give assistance to those plants where the inverter manufacturers failed.
Main strengths of the transformerless Inverter KP100L is that, thanks to ZCC embedded technology, it can replace inverters with transformer in plants with thin film modules, where grounding of negative pole is mandatory.
Quite interesting what happened in Italy: Filippo Agriman, technical and sales manager in Solarit, an italian company active in the PV sector since 2001, found a very interesting solution to replace a centralized inverter with transformer and grounded negative pole in a 70 kW plant with thin modules. The plant was connected to the Grid in 2011, and, by now, both the inverter manufacturer and the in film modules manufacturer cannot give any support.
Thin film modules may have higher parasitic capacitance than mono and polo crystalline modules. This fact induces high leakage currents and the inverter, for security reason, switches on the isolation control and stops energy output until the situation is back to standard conditions, says Eleonora Denna, Product Marketing Manager in Omron. To unsure the compliance of our Inverter with thin films we usually run tests with the modules manufacturer, to be sure that parasitic capacitance are low enough not to start this phenomenon. Unfortunately, in this case the thin film module manufacturer cannot give any support, then it was not possible to run tests and issue the declaration of compliance.
Our customer was in a very bad situation: the inverter could not be conveniently repaired, so the only chance was to replace the inverter, says Filippo Agriman, The requirements were grounding the negative pole and not to change the plant architecture: 26 strings, 10 modules each.
Our choice was the Omron Inverter: it is a transformerless inverter, but the ZCC technology grants grounding the negative pole without any other add-on. As it was not possible to have the compliance declaration, we decided to run tests on field which gave excellent results, after 30 days the production of the plant session with three string inverters is 10% better than the plant session with the old centralized inverter.
It was an interesting experience, says Eleonora Denna, Product Marketing Manager in Omron, showing with a real case that the KP100L, without any transformer, can replace successfully the inverter in plants requiring the negative pole grounded, as it happen with thin film modules. The KP100L has 3 MPPT easily configurable and wide voltage range so that it can be used in many installations without any architectural change.
