SimuGrid Lab ⚡

MATLAB/Simulink R2026a Power-Flow Transient Solver & Interactive Dashboard

SimuGrid Lab is a high-fidelity web-based transient solver and interactive visualization dashboard built to simulate the build_microgrid_r2026a Simulink power-flow model directly in the browser.

Designed for control engineers, energy researchers, and web developers, it brings Simulink equations to life using a discrete-time ODE solver, interactive block diagram inspector, and multi-axis scoping.

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📐 System Topology & Block Diagram

The microgrid system models the energy exchange between solar generation, battery storage, local loads, and the utility grid.

1. Power-Flow Schematic

This flowchart represents the physical power flow routing in the microgrid model:

graph TD
    subgraph Generation
        PV["☀️ PV Array (60kW)"] -->|Solar Power Ppv| DCDC["⚡ DC/DC Boost Converter"]
    end

    subgraph DC_Link_Bus [Central DC Link Bus]
        DCDC -->|Ppv| DCLink{"🔋 Central DC Link Capacitor (800V)"}
        BESS["🔋 Battery Storage (1ESS - 120kWh)"] <-->|Bi-directional Pbatt| DCLink
    end

    subgraph Load_and_Grid [Distribution]
        DCLink -->|Pinv| Inverter["⚡ DC/AC Inverter"]
        Inverter -->|AC Power| AC_Bus["🔌 Local AC Bus"]
        BaseLoad["🔌 Base Load (45kW)"] --> AC_Bus
        LoadStep["📈 Load Step (+10kW at t=6s)"] --> AC_Bus
        AC_Bus <-->|Net Exchange Pgrid| Grid["🌐 Utility Grid"]
    end

    style DCLink fill:#fdf2e9,stroke:#e67e22,stroke-width:2px;
    style BESS fill:#e8f8f5,stroke:#1abc9c,stroke-width:2px;
    style PV fill:#fef9e7,stroke:#f1c40f,stroke-width:2px;
    style Grid fill:#ebf5fb,stroke:#3498db,stroke-width:2px;
    style AC_Bus fill:#f4f6f7,stroke:#7f8c8d,stroke-dasharray: 5 5;

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2. Feedback Control Loop (DC Voltage Regulator)

To regulate the central DC link voltage ($V_{dc}$), a battery charge/discharge feedback controller monitors the bus voltage and controls BESS output. This flowchart represents the Simulink signal feedback path:

graph LR
    Vref["Vdc_ref (800V)"] -->|+ Input| Sum["(±) Vdc Error"]
    Vfeed["Vdc Feedback (z⁻¹)"] -->|- Input| Sum
    
    Sum -->|Vdc_Error| Kbat["Proportional Gain (Kbat = 250 W/V)"]
    Kbat -->|Power Cmd Pcmd| Limit["Battery Limit (±30kW)"]
    Limit -->|Saturated Pbatt| BESS["Battery Dynamics"]
    
    BESS -->|Pbatt Power Output| DC_Cap["Capacitor Integration (Cdc)"]
    PV_In["Ppv Power"] --> DC_Cap
    Load_In["Pinv Load"] --> DC_Cap
    
    DC_Cap -->|State Equation Vdc| Delay["Unit Delay Block (1ms Delay)"]
    Delay -->|Delayed Vdc| Vfeed

    style Sum fill:#fdedec,stroke:#e74c3c,stroke-width:2px;
    style Delay fill:#f4ecf7,stroke:#9b59b6,stroke-dasharray: 3 3;
    style Limit fill:#f5eef8,stroke:#8e44ad,stroke-width:2px;

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✨ Features

• ⚡ 1ms Discrete ODE Solver: Solves a 10-second simulation ($10,000$ iterations) using fixed-step Euler integration in under 5ms.
• 📦 Interactive Simulink Block Inspector: Click any block in the schematic grid to reveal its mathematical equations, theoretical explanation, and raw MATLAB Stateflow API constructor script.
• 📺 Multi-Axis scope (Oscilloscope): Displays high-frequency waves:
  • Left Y-Axis (Red/Green): DC Link Voltage ($V_{dc}$) showing transient sags/overshoots, and Battery SOC (%).
  • Right Y-Axis (Multicolor): Active power curves ($kW$) for PV, Battery, Load, and Grid.
• ⚙️ Live Parameter Tuning: Real-time sliders allow you to sweep parameters ($K_{bat}$ loop gains, $C_{dc}$ capacitor sizes, ratings, limits, and step times) and instantly observe transient stability responses.
• 🧪 Test Suite: Pre-integrated with a node verify_microgrid.js unit test suite to assert simulation physics, downsampling, and block metadata mappings.
•  Apple India HIG Style: A clean storefront-style light-theme layout built with token-driven styles, pill button shapes, and high contrast.

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🔬 Mathematical Formulations

The solver calculates the following equations at each step ($dt = 1\text{ms}$):

1. PV Solar power: $$P_{pv}(t) = P_{pv,rated} \times \max\left(0, \min\left(1, \frac{G(t)}{1000}\right)\right)$$ Irradiance $G$ drops from $1000 \rightarrow 700\text{ W/m²}$ at $t=5.0\text{s}$.

2. DC Link Voltage Regulation: $$P_{cmd} = K_{bat} \times (V_{dc,ref} - V_{dc})$$ $$P_{batt} = \text{clamp}(P_{cmd}, -P_{bat,max}, P_{bat,max})$$ Uses a Unit Delay ($z^{-1}$) feedback on Vdc to prevent algebraic loops.

3. Capacitor State Equation: $$\frac{dV_{dc}}{dt} = \frac{P_{pv} + P_{batt} - P_{load} \cdot K_{inv}}{C_{dc} \cdot V_{dc}}$$ $$V_{dc}(t) = V_{dc}(t-dt) + dV_{dc} \cdot dt$$

4. Grid active power balance: $$P_{grid} = P_{load} - P_{pv} - P_{batt}$$

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🚀 Getting Started

1. Run SimuGrid Lab Web Interface (Local)

Ensure you have Node.js installed, then execute:

# Install dependencies (Vite, Chart.js)
npm install

# Start the hot-reloading development server
npm run dev

Open http://localhost:5173/ in your browser.

2. Run Automated Verification Tests

Validate simulation mathematics, exponential decay rates, and metadata mapping:

node verify_microgrid.js

3. Run in MATLAB R2026a (Simulink)

The repository includes the standalone script build_microgrid_r2026a.m which programmatically creates the exact Simulink model sheet using native block integrations (no Specialized Power Systems dependencies required).

• Open MATLAB.
• Execute build_microgrid_r2026a.
• Sim the model: sim('microgrid_r2026a').

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📂 File Directory

• index.html - Dashboard viewport structure.
• src/main.js - Coordinators linking parameter sliders, solvers, and scope plots.
• src/solver.js - Euler ODE solver logic equations.
• src/diagram.js - SVG interactive block diagram layout and equations.
• src/style.css - Apple Indian HIG CSS stylesheets tokens.
• verify_microgrid.js - Node unit test validation parameters script.
• build_microgrid_r2026a.m - MATLAB Simulink model builder script.