Three Phase Grid Connected Solar PV and Battery System
Today's discussion is about a simulation model for a three-phase grid-connected solar PV and battery system using Simulink. The system includes a solar PV system, battery storage, and a grid-connected inverter.
Solar PV System Design:
250 watts PV panels connected in series with 15 modules per string and two parallel strings.
Maximum power point conditions: 30.7 volts and 8.15 amps.
PV array characteristics for different irradiation conditions.
Boost Converter Design:
Boost converter connects the solar PV system to the DC bus.
Design involves fixing input and output voltages, selecting DC bus voltage, and calculating values for inductor (L) and capacitor (C).
Battery Converter Design:
A bidirectional converter connects the battery to the DC bus.
Design involves fixing battery parameters and calculating values for inductor (L), capacitor (C), and modulation (M).
Three-Phase Inverter and Filter Design:
A three-phase inverter is connected to the grid via an LC filter.
Filter design considerations for sinusoidal voltage and current waveforms.
Control Logic:
Current control algorithm for the three-phase inverter.
ABC to DQ transformation using PLL concept.
Logic for determining power flow between grid, solar PV, and battery based on PV current and battery state of charge (SOC).
Incremental MPPT for PV System:
Incremental conductance MPPT algorithm for optimizing power output from the PV system.
Simulation Results:
Varying irradiance conditions to simulate different scenarios.
SOC of the battery initially set at 50%, later at 9%.
Observations of PV power, battery SOC, DC load power, grid power, and inverter current under changing conditions.
Conclusion:
The system dynamically adjusts power flow based on environmental conditions and battery SOC.
The control logic ensures efficient power utilization from the solar PV system, battery, and grid.