Current leakage is a fairly common systemic phenomenon in photovoltaic energy installations and it shows even in new systems, although it is clear that the age of the system plays a role. As the components age the phenomenon is increasing.
Why does the photovoltaic system generate leakage current?
Leakage current of the photovoltaic system, which is also known as the square matrix residual current, is essentially a kind of common mode current. The cause is that there is parasitic capacitance between the photovoltaic system and the earth.
What happens if a photovoltaic system is connected to a grid?
Hazard of leakage current If the leakage current in the photovoltaic system, including the DC part and the AC part, is connected to the grid, it can cause problems such as grid-connected current distortion and electromagnetic interference, so as to affect the operation of the equipment in the grid.
What type of current sensor is required for photovoltaic leakage?
And it has an extremely high precision requirement, a special current sensor is required. The photovoltaic standard stipulates that for the detection of photovoltaic leakage current, Type B, that is, a current sensor capable of measuring both AC and DC leakage currents, must be used.
Standard and detection of leakage current According to the 7.10.2 regulation of NB32004-2013 standard, in any case where the solar inverter is connected to the AC grid and the AC breaker is turned off, the inverter should provide leak current detection.
What happens if a photovoltaic system has no transformer?
However, in a photovoltaic system with no transformer, the loop impedance is relatively low, and the common mode voltage will form a large common mode current, ie, leakage current, on the parasitic capacitance between the photovoltaic system and the earth. Hazard of leakage current
Therefore, this current is also referred to as (capacitive) leakage current. 1- transformerless inverters). This leakage current is a reactive current with its phase rotated by 90° to the line voltage. In the first approximation, it is without loss. 3 How Does the Leakage Current Affect the Detection of the Residual Current?