Photovoltaic power station inverter derating operation

What is temperature derating in a PV inverter?

This process of power reduction is referred to as “temperature derating” in inverters. The inverter is a major component of photovoltaic (PV) systems either autonomous or grid connected. It affects the overall performance of the PV system. Any problems or issues with an inverter are difficult to notice unless the inverter shuts down.

What is the power derating curve for solar PV inverter?

Power derating curve with respect to temperature for three-phase 60 kW grid tie solar PV inverter. Until the external ambient (air) temperature of the inverter reaches 45°C, the inverter delivers continuous active power of 66 kW (i.e. 110% power level). The power curve follows the equation ( 1) as shown below: -

What is a derating process in an inverter?

This power reduction process is called “derating”. Derating protects sensitive components within the unit and prolongs its lifetime. When the ambient temperature falls below the specified maximum, normal power output resumes. The following inverter models operate at full power and full current up to the ambient temperatures listed in the table.

What are the different types of derating variables for PV panels?

Three different forms of derating variables, such as temperature, dirt, and manufacturing tolerance, were used to calculate such values for the two different PV panel technologies. If the inverter is designed efficiently, its nominal AC power output might be no less than 75% of the rated PV array power.

Why is power-temperature derating important for solar inverters?

The power-temperature derating aspect of solar inverters is important as most of the inverters are in general installed in rural locations of India with large land areas subjected to direct and indirect sunlight.

What are the derating factors for PV to inverter power size ratio?

InMalaysia, the typical derating factors for the PV to inverter power size ratios utilized are 1.00 to 1.30 Thin-Film and 0.75 to 0.80 for the c-Si PV type .