Manufacturers of single and dual axis tracking brackets will take you to understand the impact of distributed photovoltaic power generation system access on distribution network fault handling today:

Photovoltaic grid-connected inverters are generally equipped with a current limiter, whose function is to limit the current delivered by the inverter and correspondingly limit the increase of the fault current. Compared with the current limiter, this device reduces the fault current. For a distributed photovoltaic power generation system with a power electronic interface, if the current limiter in the inverter does not operate normally, the contribution to the fault current level can be ignored, which allows multiple distributed photovoltaics to be connected to the same grid. Redesign existing feeder protection schemes. When the distributed photovoltaic access capacity is small, the current injected into the grid is limited to the rated value of the inverter. However, the impact of current limiters is no longer considered to be negligible when injected into distribution networks where the level of PV penetration continues to increase.

The distributed photovoltaic power generation system is connected to the power distribution system through a 10kV feeder. When a fault occurs, the magnitude and distribution of the fault current are obviously different from those when the distributed photovoltaic system is not connected. When the penetration rate of the distributed photovoltaic power generation system is high, it will affect the normal operation of the original relay protection device of the distribution network. Due to the boosting or shunting effect of distributed photovoltaics on the fault current, the current flowing through the protection device may increase or decrease, which will change the protection range and sensitivity, and bring difficulties to the mutual cooperation of various protection devices.

Generally speaking, the photovoltaic inverter has been equipped with complete protection functions when it leaves the factory, and various abnormal situations that may occur in actual use have been considered to protect the inverter itself and other components of the system from damage. The protection functions that the inverter itself should be equipped with generally include: input and output under-overvoltage protection, over-current protection, output short-circuit protection, anti-islanding protection, under-overfrequency protection, lightning protection, over-temperature protection, etc.