APF 3P3W/3P4W-WM Series 50A–200A Wall Mount Active Power Filter

Description

This wall-mounted Active Power Filter (APF) series is a new-generation power electronic harmonic suppression device based on voltage source inverter. Equipped with full-digital DSP controller and IGBT power modules, it detects load current waveforms in real time and dynamically outputs reverse compensation current to comprehensively resolve power quality issues including harmonic pollution, insufficient reactive power, three-phase unbalance, voltage fluctuation and grid resonance.

The series covers 50A–200A compensation current with two wiring types: 3-phase 3-wire (3P3W) and 3-phase 4-wire (3P4W). Multiple installation options are available: wall mount, rack mount and stand mount. Standard enclosure color is RAL7035 grey, with customizable voltage, capacity and appearance. Featuring ultra-fast response, wide filtering range and high efficiency without harmonic amplification risk, the APF fits all non-linear load applications and fully complies with IEC international power quality standards.

Working Principles:

• External Current Transformer (CT) samples real-time load current;
• Built-in DSP chip performs high-speed calculation to extract harmonic, reactive and unbalanced current components;
• Controller sends PWM drive signals to IGBT power units;
• The APF injects compensation current with equal amplitude and opposite phase into the grid to offset harmonics, dynamically compensate reactive power and balance three-phase current.

Main Functions：

• Harmonic Filtering: Filters 2nd–51st harmonics under harmonic-only mode; priority mode targets 2nd–13th low-order harmonics with filtering efficiency up to 97.5%;
• Dynamic Reactive Power Compensation: Stepless regulation of inductive/capacitive reactive power, lifting power factor above 0.95 to avoid reactive penalty and reduce transformer & cable loss;
• Three-Phase Unbalance Correction: Split-phase compensation for neutral unbalanced current, ideal for charging stations, IDC rooms and buildings with massive single-phase loads;
• Customizable Operation Priority: 4 switchable modes: H+Q / Q+H / Q+H+B / H+Q+B (H=harmonic, Q=reactive power, B=unbalance);
• Resonance Suppression: Prevents parallel grid resonance and avoids harmonic amplification of capacitor banks;
• Full Protection System: Integrated protection against overvoltage, undervoltage, overcurrent, short circuit, overtemperature, detuning and overload;
• Communication Interface: Standard RS485 port for remote monitoring and parameter adjustment via HMI, PLC or SCADA;
• Parallel Expansion: Max. 5 modules parallel in one system, customized higher capacity available.