Sistema para ensaio de corrente de fuga em inversores fotovoltaicos de acordo com a norma iec 62109-2

Abstract

Grid-tied photovoltaic inverters may present several problems that offer risks to users and its components. One of these problems is the common-mode leakage current, caused by the presence of parasitic capacitances between the photovoltaic modules and the ground, or by insulation faults in the system. In order to ensure the safety of the users and the structure of photovoltaic systems, inverters must be submitted to a series of tests to ensure if it complies with the safety standards. The international standard IEC 62109-2 shows the risks and determines safety limits of leakage current in photovoltaic inverters, and inverters safety devices test procedures. This work presents the design and implementation of a photovoltaic inverter leakage current testing system, composed of an electronically controlled variable RC load and a supervisory system, which operating together are capable of performing leakage current tests according to the procedures defined in standard IEC 62109-2 in an automated way. Finally, results of leakage current tests of three samples of commercial inverters are presented, all carried out using the system.