⚡ Power Factor & Harmonics Analyzer

🎯 Getting Started

This tool analyzes AC power quality and helps you design power factor correction systems:

• Power Factor Analysis: Calculate real, reactive, and apparent power from voltage and current values
• Harmonics Analysis: Measure Total Harmonic Distortion (THD) using FFT on waveform data
• Capacitor Bank Design: Calculate exact capacitor size needed to improve power factor
• Waveform Visualization: View voltage and current waveforms with phase relationships

⚡ Power Factor Fundamentals

Power Factor (PF) is the ratio of real power (watts) to apparent power (VA):

• PF = P / S = cos(φ) where φ is the phase angle between voltage and current
• Real Power (P): Actual power consumed, measured in Watts (W)
• Reactive Power (Q): Power oscillating between source and load, measured in VAR
• Apparent Power (S): Total power delivered, measured in VA (Volt-Amperes)

Lagging Power Factor: Current lags voltage (inductive loads like motors, transformers)

Leading Power Factor: Current leads voltage (capacitive loads)

Unity power factor (PF = 1.0) is ideal - all power is converted to useful work.

🔧 Power Factor Correction

Adding capacitors in parallel with inductive loads improves power factor by supplying reactive power locally:

Capacitor Value Calculation:

Q_c = P × (tan(θ₁) - tan(θ₂))

C = Q_c / (2πfV²)

• Q_c = Reactive power to be compensated (VAR)
• P = Real power (W)
• θ₁ = Angle of original power factor
• θ₂ = Angle of target power factor
• f = Frequency (Hz)
• V = Voltage (V RMS)

⚠️ Typical target: 0.95 to 0.98 PF (not 1.0 to avoid overcompensation)

📊 Harmonic Distortion (THD)

Total Harmonic Distortion (THD) measures how much a waveform deviates from a pure sine wave:

THD = √(V₂² + V₃² + V₄² + ... + Vₙ²) / V₁ × 100%

• V₁ = Fundamental frequency amplitude (50/60 Hz)
• V₂, V₃, ... = Harmonic amplitudes (multiples of fundamental)

THD Guidelines:

• < 5%: Excellent power quality (IEEE 519 recommended limit)
• 5-10%: Acceptable for most applications
• 10-20%: May cause issues with sensitive equipment
• > 20%: Poor power quality, equipment may malfunction

Harmonics are caused by non-linear loads: switching power supplies, VFDs, LED drivers, rectifiers.

🌊 Waveform Data Input

To analyze harmonics using FFT, provide sampled waveform data:

• Format: One voltage/current value per line, comma-separated values, or space-separated
• Sample Rate: Must be at least 2× highest frequency of interest (Nyquist theorem)
• Recommended: 128-512 samples per cycle for good frequency resolution
• Example: For 60 Hz with 256 samples/cycle, sample at 15.36 kHz

The tool uses FFT (Fast Fourier Transform) to extract harmonic components from the waveform.

💡 Design Tips

• Don't Overcorrect: Target 0.95-0.98 PF, not 1.0 (avoid leading power factor penalties)
• Capacitor Sizing: Use standard capacitor values (round up from calculated value)
• Voltage Rating: Capacitors should be rated 1.5-2× system voltage for safety margin
• Resonance Risk: Large capacitor banks can resonate with system inductance
• Switching Control: Use contactors to disconnect capacitors during light load
• Harmonics Impact: High THD reduces effective power factor even after correction