WEC Model

WEC Model - Wave Energy Converter to Grid

This directory contains the complete Wave Energy Converter (WEC) model with grid integration capabilities, including low-voltage ride-through (LVRT) functionality.

Overview

The WEC-to-Grid system model is a comprehensive Simulink implementation that simulates a single-body wave energy converter with power take-off (PTO), energy management system, and grid-connected inverter with fault ride-through capabilities.

Model Files

• WEC2G_EMS_ok_LVRT_FMU.slx - Full model configured for FMU export
• WEC2G_EMS_ok_standalone.slx - Standalone version for Simulink-only simulation
• WEC2G_EMS_ok_LVRT_FMU.fmu - Pre-compiled FMU for co-simulation with PowerFactory or other tools

System Architecture

The WEC-to-Grid system consists of four integrated subsystems:

1. Wave Energy Converter (WEC Body)

Figure: Complete WEC-to-Grid system model

Figure 1: Wave Energy Converter subsystem

• Inputs: Wave height, wave period
• Outputs: WEC velocity and position
• Control: Passive damping controller for maximum energy extraction from ocean waves
• Function: Converts wave motion into mechanical energy through the PTO system

2. Power Take-Off (PTO) and Energy Management System

Figure 2: Linear permanent magnet generator and energy management system

• Generator: Linear permanent magnet generator model
• Function: Converts mechanical energy to electrical energy
• Energy Management System (EMS): Smooths fluctuations in PTO output power
• Output: Regulated electrical power

3. Supercapacitor and Boost Converter

Figure 3: Supercapacitor energy storage and boost converter

• Energy Storage: Supercapacitor bank for power smoothing
• DC-DC Converter: Boost converter for voltage regulation
• Function: Absorbs power fluctuations and maintains stable DC-link voltage
• Control: Regulates DC-link voltage to reference level

4. Grid-Connected Inverter with Fault Ride-Through

Figure 4: Grid-connected inverter with LVRT control

• Inverter: Three-phase grid-connected inverter
• Control: Low-Voltage Ride-Through (LVRT) capability implemented
• Function: Converts DC power to AC and maintains grid synchronization
• Features: Fault ride-through compliance for grid code requirements

Key Features

• ✅ Complete wave-to-wire modeling
• ✅ Passive damping control for optimal energy extraction
• ✅ Energy management system for power smoothing
• ✅ Supercapacitor integration for transient compensation
• ✅ Grid-compliant LVRT control
• ✅ FMU export capability for co-simulation

Using the Model

Standalone Simulation (Simulink)

1. Open WEC2G_EMS_ok_standalone.slx in MATLAB/Simulink
2. Configure wave input parameters (height, period)
3. Run simulation
4. Analyze results (power output, voltage, current)

FMU Co-simulation (with PowerFactory)

1. Use the pre-compiled WEC2G_EMS_ok_LVRT_FMU.fmu file
2. Import into PowerFactory (see FMU Method guide)
3. Connect to grid model at designated bus
4. Configure interface variables
5. Run co-simulation

Exporting Your Own FMU

1. Open WEC2G_EMS_ok_LVRT_FMU.slx
2. Use Simulink FMU export functionality
3. Follow the FMU Method guide for configuration

Model Inputs

• Wave Height (m) - Significant wave height
• Wave Period (s) - Wave period
• Grid Voltage - Three-phase grid voltage

Model Outputs

• Active Power (W) - Power injected to grid
• Reactive Power (VAr) - Reactive power exchange
• DC-link Voltage (V) - Intermediate DC voltage
• WEC Position/Velocity - Mechanical state variables