Module mppt 

Maximum Power Point Tracking (MPPT) Algorithms

This module provides implementations of Maximum Power Point Tracking algorithms commonly used in photovoltaic (PV) systems and other renewable energy applications. MPPT algorithms optimize power extraction from variable sources like solar panels.

Theory

The maximum power point (MPP) of a photovoltaic array varies with:

• Irradiance levels: Higher light intensity increases power output
• Temperature: Higher temperatures generally reduce voltage and power
• Partial shading: Can create multiple local maxima
• Array degradation: Aging affects the characteristic curves

Available Algorithms

Perturb and Observe (P&O)

• perturb_and_observe - Classical hill-climbing algorithm
• Principle: Perturb voltage and observe power change
• Advantages: Simple implementation, low computational cost
• Disadvantages: Oscillates around MPP, can be confused by rapid irradiance changes

Incremental Conductance (IC)

• incremental_conductance - Advanced gradient-based method
• Principle: Uses dP/dV = 0 condition at MPP
• Advantages: Can detect when MPP is reached, better dynamic response
• Disadvantages: More complex implementation, sensitive to noise

Algorithm Comparison

Feature	P&O	IC
Simplicity	High	Medium
Speed	Fast	Medium
Steady-state accuracy	Medium	High
Dynamic response	Medium	Good
Noise sensitivity	Low	Medium
Memory requirements	Low	Low

Implementation Considerations

Step Size Selection

• Large steps: Faster tracking, more oscillation
• Small steps: Slower tracking, less oscillation
• Adaptive step size: Optimal compromise (not implemented)

Sampling Frequency

• Typical range: 1-100 Hz depending on application
• Trade-offs: Faster sampling vs. computational load
• Consideration: PV array time constants (typically slow)

Practical Considerations

• Voltage and current measurement accuracy
• Converter dynamics and control loop interactions
• Protection against out-of-range operating points
• Startup and shutdown procedures

Applications

• Grid-tied solar inverters
• Battery charging systems
• Standalone PV systems
• Solar water pumping
• Electric vehicle solar charging
• Building-integrated photovoltaics (BIPV)

Example Usage

use libpower::mppt::perturb_and_observe::MPPT;

// Create and configure MPPT tracker
let mut mppt = MPPT::new();
mppt.set_step_size(0.1);           // 0.1V step size
mppt.set_mppt_v_out_max(24.0);     // 24V maximum
mppt.set_mppt_v_out_min(12.0);     // 12V minimum

// Simulate control loop samples
let pv_measurements = [
    (5.0, 18.0),  // (current, voltage) pairs
    (5.1, 18.2),
    (5.2, 18.1),
];

for (pv_current, pv_voltage) in pv_measurements.iter() {
    mppt.calculate(*pv_current, *pv_voltage);     // Run MPPT algorithm
    let reference_voltage = mppt.get_mppt_v_out(); // Get voltage reference
    // In real application: set_converter_reference(reference_voltage);
}

Modules

incremental_conductance

Incremental Conductance (IC) MPPT Algorithm

perturb_and_observe

Perturb and Observe (P&O) MPPT Algorithm