Advanced Large-Scale Solar Power Simulation | Boost Converter | Grid Integration

Large-scale solar power plants require robust control, accurate MPPT algorithms, and efficient power conversion stages to maintain reliable grid-connected operation. This article explains the working of a 5 MW Grid-Connected PV System using Incremental Conductance MPPT, covering system design, control strategies, and simulation performance.

🌞 1. System Overview

The simulated PV plant consists of:

• 11 PV modules in series per string

• Each module defined by:

  • Voltage at MPP

  • Current at MPP

  • Open-circuit voltage

  • Short-circuit current

The PV array feeds power into a boost converter, which stabilizes and conditions the DC voltage. The boosted output is then supplied to a grid-connected inverter for AC power delivery.

This multi-stage architecture ensures high efficiency, wide operational flexibility, and reliable integration with the utility grid.

🔋 2. Boost Converter Design

The boost converter plays a key role in:

• Stepping up the PV voltage

• Maintaining the DC-link at 800 V

• Supporting stable inverter operation

• Smoothing PV fluctuations caused by irradiation and temperature changes

Design Considerations

• Inductor current ripple (%): optimized to avoid excessive switching losses

• Capacitor voltage ripple: minimized to ensure stable DC-link voltage

• Switching frequency: selected to balance efficiency and response time

A properly tuned boost converter ensures maximum power transfer from the PV array to the grid.

📈 3. Incremental Conductance MPPT

To extract maximum power under varying environmental conditions, the system uses the Incremental Conductance (INC) MPPT algorithm.

Why INC MPPT?

• More accurate than Perturb & Observe (P&O)

• Quickly identifies MPP by comparing dI/dV with –I/V

• Reduces oscillations around the MPP

• Efficient under fast-changing irradiation

The INC algorithm continuously monitors PV voltage and current, adjusting the duty cycle of the boost converter to keep the operating point at the maximum power point in real time.

⚡ 4. Grid Inverter and Filter Design

After boosting, the DC power is converted to AC using a three-phase grid-tie inverter.

Key Functions

• DC to AC conversion

• Synchronization with grid voltage and frequency

• Control of active and reactive power

• Regulation of current injected into the grid

A harmonic filter is employed to:

• Reduce switching harmonics

• Ensure a smooth sinusoidal grid current

• Meet IEEE standards for power quality

Advanced control algorithms regulate voltage, current, and power factor at the grid interface.

🧪 5. Simulation Results

The model provides clear insights into system behavior under real-world conditions:

Observations

• As irradiation increases → PV output rises, reaching up to 5 MW

• Boost converter maintains steady 800 V DC-link

• Grid inverter outputs clean AC waveforms

• Grid current and voltage remain stable

• Power flow between PV, DC-link, and grid remains balanced

• Modulation signals vary smoothly with changing environmental input

The dynamic performance confirms that the system can handle environmental variations without compromising grid stability.

✅ Conclusion

This 5 MW grid-connected PV simulation demonstrates the importance of combining:

• Incremental Conductance MPPT,

• Optimized boost conversion, and

• Grid-synchronized inverter control

The setup ensures maximum power extraction, stable grid operation, and reliable integration of large-scale solar energy into the power network. Such models help in planning and analyzing renewable power plants, contributing significantly to sustainable and efficient energy generation.