MATLAB Simulation of 15 kW OFF-grid PV battery System
We will explore a simulation model of a 15 KW off-grid PV (Photovoltaic) battery system developed by MATLAB. This system integrates solar power generation with battery storage to provide a reliable and sustainable energy solution.
PV Array Characteristics:
The system begins with a PV array, consisting of individual panels with a power rating of 193 watts. Each panel operates at a voltage of 28.944 volts and a current of 6.68 amps. The simulation considers three parallel strings of 26 panels each, resulting in a total power generation of approximately 15.08 KW under 1,000 W/m² irradiance.
PV-Battery Connection:
The PV array is connected to a battery through a DC-DC converter (BU converter). This converter steps down the PV array voltage of 750 volts to match the battery voltage, which is 54 volts in this case. The BU converter is controlled by a charger controller that processes PV measurements to generate a duty cycle, optimizing power extraction from the PV array.
Battery Configuration:
The battery is configured with a voltage of 54 volts and a rated capacity of 200 Ah. A circuit breaker is incorporated into the system with conditions for disconnecting the PV array if the power is less than 300 and PV voltage is less than 50 volts, ensuring the safety and efficiency of the system.
DC Load and Inverter:
DC loads, such as LED lights, are powered directly from the battery. An inverter converts DC power to AC power for various applications, including appliances like refrigerators, washing machines, air conditioners, and more.
Control System:
The control system ensures seamless operation by managing the connection and disconnection of the PV array based on real-time irradiance changes. A Proportional-Integral (PI) controller is employed to regulate the inverter and maintain a stable AC supply for the connected loads.
Measurement and Monitoring:
The system incorporates measurement blocks for monitoring PV parameters, battery performance, AC and DC loads, and inverter current. Real-time simulation allows for observing the dynamic changes in waveforms as irradiance levels fluctuate.
Conclusion:
The simulation model provides valuable insights into the operation of a 15 KW off-grid PV battery system, showcasing its ability to efficiently utilize solar power for both DC and AC loads. This integrated approach ensures a reliable and sustainable energy supply, contributing to a greener and more resilient power infrastructure.