Dc Reactor Smoothing Reactor

DC Reactor (Smoothing Reactor) Technical Summary

Core Functions

Harmonic Suppression: Limits AC ripple (20–150Hz) on the DC side (typical ≤10% of rated current).

Power Factor Improvement: Increases input PF from 0.75 to 0.95 (50Hz operation).

Current Continuity: Maintains minimum critical current to prevent rectifier discontinuity.

Key Specifications

Inductance: 1–30 mH (varies with inverter power rating)

Current Rating: 100–3000 A

Voltage Drop: <2% of rated voltage

Application Scenarios

Class A (Mandatory Installation):

Grid THDv >5% or short-circuit capacity >40× inverter rating

Multi-inverter parallel systems (≥3 units)

Class B (Recommended Installation):

Transformer capacity >10× inverter rating (impedance <4%)

Voltage imbalance rate: 1.8–3%

Class C (Optional Installation):

Systems with reactive power compensation (anti-resonance required)

Long cable feeds (>100 m)

Installation Guidelines

Distance to inverter: <5 m (to minimize line inductance effects)

Spacing from capacitors: ≥3× device length

Must be optimized for IGBT switching frequency (typically 2–8 kHz)

Protection Features

Built-in temperature sensors (85°C alarm, 105°C trip)

Insulation class: F (155°C)

Sizing Formula:L min =( 2π⋅f⋅ΔIΔU)⋅K(ΔU: allowable ripple voltage, f: ripple frequency, ΔI: allowable ripple current, K: safety factor 1.2–1.5)

Performance Benefits:

Reduces input harmonic current by 40–60%

Decreases capacitor thermal losses by 15–25%

Complies with IEEE 519-2014 standards for harmonic mitigation.