On Grid Systems

The on-grid solar power system is a solar power generation system that is connected to the utility grid. The electricity produced by the system is routed to the grid. The installation of this type of system is very easy to install and easy to maintain. Solar Array produces Direct Current (DC). This DC passes through the Array Junction Box (AJB) to the Inverter. Inverter Consumes DC to produce Alternative Current (AC).

When an inverter starts first it samples different parameters of the grid, like Voltage Frequency and Phase. Then the inverter starts producing power which is synchronized to the grid. This synchronized power flows to the grid through the Net Metering system that measures power export to the grid. In the absence of the sun (e.g. Night, Cloudy Day) loads consume power from the grid. The net meter calculates the net consumption/export of power.

SPV Array: 
A solar photovoltaic array is formed by a series/parallel combination of SPV modules to attain the desired voltage and current level.

Array Junction Box (AJB): 

Typically the surge device will trigger at a set voltage, around 3 to 4 times the mains voltage, and divert the current to earth. Some devices may absorb the spike and release it as heat. They are generally rated according to the amount of energy in joules they can absorb.

Inverter:
A grid-tie inverter converts direct current into an alternating current suitable for injecting into an electrical power grid. To inject electrical power efficiently and safely into the grid, grid-tie inverters must accurately match the voltage and phase of the grid sine wave AC waveform.

Inverter Interfacing Panel (IIP):
The Inverter Interfacing Panel usually contains one MCB and one AC Surge Protection Device(SPD). It is mainly used to isolate the while maintenance.

Reference:
[1] https://creativestudio1973.blogspot.com/2021/06/introduction-to-solar-panel.html
[1] https://en.wikipedia.org/wiki/Surge_protector
[2] https://creativestudio1973.blogspot.com/2021/09/surge-protection-device.html
[3] https://creativestudio1973.blogspot.com/2023/10/array-and-array-junction-box.html