Name: GY-AHF Active Harmonic Filter - GEYA Electrical Equipment Supply
SKU: GY-AHF

Description

GY-AHF Active Harmonic Filter – Overview

The GY-AHF Active Harmonic Filter is a modular active power filter designed to eliminate 2nd–50th order harmonic currents in low-voltage and medium-voltage power systems from AC220V to AC800V. Built on a DSP+CPLD full digital control core with three-level topology, it delivers a current harmonic compensation rate of ≥95%, a full response time of less than 40ms, and optional three-phase unbalance compensation, making it a reliable power quality solution for industrial plants, data centers, commercial buildings and renewable energy facilities.

Working Principle

The GY-AHF operates by detecting the load current in real time. Based on a specified-order harmonic current detection algorithm, harmonic currents are separated order by order. Control signals are then generated according to the pre-set filtering percentage, driving the IGBT power stage to inject a compensation current with the same amplitude and opposite phase as the load harmonic current. The harmonic components are cancelled at the point of connection, achieving accurate and dynamic harmonic compensation.

Key Features

DSP+CPLD full digital control core with three-level topology, advanced harmonic detection algorithm and PWM control strategy.
Modular design allows multiple modules to be connected in parallel with no restriction on quantity, offering a small footprint and easy maintenance.
Independent air duct and independent plate compartment structure design ensure stable, long-term operation of the equipment.
100% current limiting output can be set to protect the device and guarantee continuous stable operation.
Selectable operating modes: harmonic compensation, or harmonic compensation + three-phase unbalance compensation.
Current harmonic compensation rate ≥95%; unbalance degree after compensation ≤5%.
2nd–50th order harmonic filtering with individually adjustable compensation rate per order.
2 x RS485 communication interfaces with Wi-Fi support for flexible monitoring and integration.

Reliable Protection & Overload Capability

The GY-AHF integrates comprehensive protection functions, including overload, software/hardware overcurrent, grid overvoltage/undervoltage, grid voltage imbalance, power supply failure, overtemperature, frequency anomaly and short-circuit protection. The unit withstands 1.2 times rated overload for 60 seconds, and the overall efficiency reaches ≥97%, ensuring dependable performance in demanding electrical environments.

Flexible Installation Options

Two mounting configurations are available: rack-mounted modules with rear cable entry and wall-mounted modules with top cable entry. The standard protection rating is IP20, with IP54 available on request. Suitable operating conditions include altitudes below 2000m (derating per GB/T 3859.2 above 2000m), ambient temperatures of -10°C to +50°C, and relative humidity ≤90% without condensation.

Typical Applications

Industrial plants with variable frequency drives, rectifiers and welding equipment
Data centers, hospitals and commercial buildings with UPS and IT loads
Photovoltaic, wind power and energy storage systems
Municipal facilities, rail transit and other harmonic-sensitive power distribution systems

Technical Parameters

Item	220V (Single-phase)	220V	380V	500V	690V	800V
Operating Voltage	AC220V (-20%~+20%)	AC220V (-20%~+20%)	AC380V (-20%~+20%)	AC500V (-20%~+20%)	AC690V (-20%~+15%)	AC800V (-20%~+850V)
Operating Frequency	50Hz/60Hz (45Hz~63Hz)
Rated Compensation Capacity	25A	7/15/25/50/75/100/150/200A		100A		100A
Grid Configuration	L/N	Three-phase three-wire / Three-phase four-wire				Three-phase three-wire
Number of Parallel Units	No restrictions
Overall Efficiency	≥97%
Switching Frequency	16kHz			12.8kHz
Function Selection	Harmonic compensation	Harmonic compensation / Harmonic compensation + three-phase unbalance compensation				Harmonic compensation
Harmonic Compensation Range	2nd~50th order, with adjustable compensation rate per order
Current Harmonic Compensation	≥95%
Unbalance Compensation Capability	Unbalance degree after compensation ≤5%
Full Response Time	<40ms
Noise Level	≤60dB	≤65dB			≤65dB
Communication Method	2 x RS485 communication interfaces (Wi-Fi supported)
Protection Functions	Overload, software/hardware overcurrent, grid over-/undervoltage, grid voltage imbalance, power supply failure, overtemperature, frequency anomaly, short-circuit protection, etc.
Overload Capability	1.2 times rated overload for 60 seconds
Installation Method	Rack-mount / Wall-mount
Cable Entry	Rear entry (rack-mount) / Top entry (wall-mount)
Protection Rating	IP20 (IP54 available on request)
Altitude	<2000m; above 2000m, derate according to GB/T 3859.2
Ambient Temperature	-10°C to +50°C (above 40°C, capacity derating ≤30%)
Relative Humidity	≤90%, no condensation on the surface at a monthly minimum temperature of 25°C
Pollution Degree	≤ Class III

Frequently Asked Questions

1. What is the GY-AHF Active Harmonic Filter?

The GY-AHF is a modular active harmonic filter (AHF) that detects load current in real time, separates harmonic currents order by order using a specified-order detection algorithm, and drives IGBTs to inject compensation currents with equal amplitude and opposite phase. This cancels harmonic distortion at the source and improves overall power quality in the electrical system.

2. What core functions does it provide?

It provides dynamic harmonic compensation for 2nd–50th order harmonics with a compensation rate of ≥95%, and an optional harmonic compensation + three-phase unbalance compensation mode that reduces the unbalance degree to ≤5%. The full response time is less than 40ms, and the compensation rate for each harmonic order can be individually adjusted.

3. Which key parameters should I consider when selecting a model?

The main selection factors are: system voltage (AC220V/380V/500V/690V/800V), rated compensation capacity (25A–200A per module depending on voltage class), grid configuration (single-phase L/N, three-phase three-wire or three-phase four-wire), required compensation mode (harmonic only or harmonic + unbalance), installation type (rack-mount or wall-mount), and site conditions such as altitude, ambient temperature and required IP rating.

4. What options and specifications are currently available?

The GY-AHF series covers AC220V (25A single-phase; 7–200A three-phase), AC380V (7–200A), AC500V (100A), AC690V (100A) and AC800V (100A) modules. Both rack-mounted (rear cable entry) and wall-mounted (top cable entry) versions are available. Modules can be connected in parallel without restriction to scale up compensation capacity, and IP54 protection is available on request in place of the standard IP20.

5. Which standards does it follow and which markets is it designed for?

The product follows GB/T 3859.2 for altitude derating and is engineered to help facilities meet widely adopted harmonic limits such as those defined in IEEE 519 and IEC 61000 series guidelines. With 50Hz/60Hz (45Hz–63Hz) frequency compatibility and voltage classes from 220V to 800V, it is suitable for industrial and commercial power systems across Asia, Europe, the Middle East, Africa and the Americas. Please contact us for the specific certification documents required in your market.

6. What should I pay attention to during installation and maintenance?

Install the unit at altitudes below 2000m (derate per GB/T 3859.2 above 2000m), in ambient temperatures of -10°C to +50°C (derate capacity by up to 30% above 40°C), with relative humidity ≤90% and no condensation, and pollution degree not exceeding Class III. Ensure adequate ventilation for the independent air duct design, follow the correct cable entry direction (rear for rack-mount, top for wall-mount), and verify CT wiring polarity before energizing. The modular structure allows individual modules to be serviced or replaced without shutting down the entire system, simplifying routine maintenance.

GY-AHF Active Harmonic Filter