Modeling of Solar PV Plant

1. Solar PV Panel

It converts sun’s rays into electricity by exciting electrons in silicon cells using the photons of light from sun. 

2. Battery Bank

For Solar plant lead acid deep-cycle storage batteries are used for storing the energy generated by PV panels for providing backup to the system when sun is not present.  DOD is the complement of State of Charge (SOC). It describes the degree to which a battery is emptied relative to its total capacity. This affects the length of the battery’s operational life, as well as the total number of kilowatt-hours it will be able to store over its lifetime. DOD should be taken as 50%. If a lead-acid battery is discharged 100% every time its electrolyte will quickly degrade compared to if it were only discharged to a maximum of 50%. 
3. MPPT Charge Controller

Maximum Power Point Tracker (MPPT) is a kind of charge controller that utilizes the solar panel power to its maximum potential. The MPPT fools the panels by giving output with different voltage and current which will allow more power to go into the batteries. Output voltage and current from the solar panel is monitored by MPPT and operating point that will deliver that maximum amount of power to the batteries will be determined. MPPT can accurately track the always-changing operating point where the power is at its maximum, thus the efficiency of the solar cell will be increased. Many algorithms have been developed for tracking maximum power point of a PV generator such as Perturb and Observe (P&O), Incremental Conductance, and fuzzy logic based tracking techniques. These algorithms vary in effectiveness, complexity, convergence speed, sensors required and cost.

4. Power Converter

HRES that contains both AC and DC elements requires a converter. It acts as both rectifier and inverter accordingly.