GY-AHF ACTIVE HARMONIC FILTER CABINETS

Name: GY-AHF Active Harmonic Filter Cabinets
Brand: Ningbo Gaoyun Electric Co., Ltd. | Power Quality Equipment Manufacturer
SKU: 26147
Availability: InStock

Rack-mount active harmonic filter — 30–150 A per module, THDi reduced below 5%, sub-5 ms response

GY-AHF Active Harmonic Filter Cabinets product image

2nd–50th Order Harmonic Elimination | THDi Reduced Below 5%

Response Time Under 5 ms | Real-Time Dynamic Correction

30–150 A Rack Modules | Up to 10 Units Paralleled

Harmonics, Reactive Power and Unbalance | Corrected Simultaneously

Harmonics, Reactive Power & Unbalance | Corrected Simultaneously

Get Free Technical Quotation Download Full Datasheet PDF

Quick Specs

Parameter	Specification
Voltage Class	0.4 kV
Product Ratings	30 A, 50 A, 75 A, 100 A, 150 A
Grid Voltage	400 V (−20% ~ +20%)
Grid Frequency	50 / 60 Hz (−5 Hz ~ +5 Hz)
Max. Parallel Units	≤ 10 units
Active Power Loss	< 2% at rated full load
System Wiring	3-Phase 4-Wire (3P4W)
Current Transformer Ratio	100/5 – 10000/5
Harmonic Filtering Range	2nd ~ 50th harmonics
Harmonic Order Setting	Individual configuration for each order and percentage
Overall Efficiency	0.97
Response Time	< 5 ms
Noise Level	< 65 dB
Communication Interfaces	RS485, Ethernet port
Communication Protocols	Modbus, TCP/IP
Altitude	≤ 2000 m (derate 1% per additional 100 m)
Operating Temperature	−25 °C ~ +55 °C
Relative Humidity	5% ~ 95%, non-condensing
Ingress Protection	IP20 (custom IP ratings available)

Data measured at rated load and 25 °C ambient. Custom voltage, current and enclosure versions are available on request.

Typical Applications

Non-linear loads are everywhere in modern distribution systems. The GY-AHF is applied wherever variable-frequency drives, rectifiers, UPS systems or switching power supplies distort the current waveform.

Data Centers

Harmonics generated by UPS, servers and cooling drives are filtered at the source, securing clean power for critical IT loads and preventing neutral overload.

Renewable Energy

Suppresses switching harmonics from solar and wind inverters, keeps THDi within grid-code limits and protects inverters and cabling from thermal stress.

Manufacturing

Reduces harmonics from VFDs, welding sets and arc furnaces in automotive, steel and machining plants, improving motor efficiency and lowering losses.

Oil & Gas

Filters nonlinear loads from pumps, compressors and VSDs, improving system reliability in refineries and offshore installations.

Healthcare

Protects MRI, CT and imaging suites from voltage distortion, meeting the strict power quality standards of hospitals and laboratories.

Water & Wastewater

Cleans harmonics from variable-speed pumps and blowers, extending equipment life and reducing unplanned downtime at treatment plants.

Commercial Buildings

Corrects power factor and reduces neutral current caused by LED drivers, chillers and elevators in offices, malls and airports.

Transportation

Mitigates traction-converter harmonics on railways and stabilises the grid supply of DC fast-charging hubs and metro stations.

Why Choose This Product

GY-APF Series Active Power Filters

Tailored Power Quality Solutions for Industrial Applications

How It Works

The GY-APF Series Active Power Filters (APF) are connected in parallel with the power grid to continuously detect harmonic currents and reactive power components generated by non-linear loads, including VFDs, rectifiers, and switching power supplies.

By leveraging advanced PWM (Pulse Width Modulation) technology, the APF injects equal-but-opposite compensation currents into the distribution system, achieving three core objectives:

✓Suppression of Harmonics (up to the 50th order)

✓Dynamic Reactive Power Compensation

✓Three-Phase Load Balancing

APF Active Power Filters

A rugged, high-performance variant engineered for demanding environments.

Capacity Range: 50–150 A Applications: Heavy industry, commercial buildings, sites with high single-phase loads, and harsh operating conditions

Advanced Features

Dual DSP controller architecture for ultra-fast, stable response

Real-time temperature monitoring and fan alarm functions

Precise fault feedback for simplified maintenance

Model Code Explanation (GY-APF-0.4/100-4L/DM)

Key Benefits of the GY-APF Series

Improved Power Quality

Reduces harmonic distortion and corrects power factor.

Enhanced Equipment Reliability

Protects motors, transformers, and sensitive electronics from harmonic damage.

Energy Savings

Lowers energy consumption and reduces utility penalties for poor power factor.

Easy Integration

Rack-mount design for simple installation in standard cabinets.

Proactive Monitoring

Industrial models offer comprehensive diagnostics and protection features.

WORKING PRINCIPLE

Schematic diagram of the GY-AHF active harmonic filter: three-phase grid with current transformers CT feeding a non-linear load, a DSP control system calculating the reference current, and a three-phase IGBT bridge PWM converter injecting the compensation current iC through filter inductors

The GY-AHF is connected in parallel with the distribution system, downstream of the current transformers and in parallel with the non-linear load. It never carries the full load current, so a fault in the filter does not interrupt production.

Current transformers measure the load current continuously. The DSP controller decomposes it into fundamental, harmonic and reactive components, then calculates the reference compensation current for each harmonic order from the 2nd to the 50th.

A three-phase IGBT bridge, switched by PWM at high frequency and smoothed by the filter inductors and DC-link capacitors, injects a current of equal amplitude and opposite phase. The harmonic current is cancelled inside the installation instead of flowing back to the transformer.

The result is one device performing three tasks at the same time: harmonic suppression, dynamic reactive power compensation and three-phase load balancing — with a closed-loop response of less than 5 ms.

INTERNAL STRUCTURE

Eleven functional layers make up one GY-AHF rack module. The exploded view below shows the real assembly sequence, from the front panel to the chassis housing.

Exploded view of the GY-AHF active harmonic filter rack module showing eleven layers: front panel and HMI, front air vent grille, IGBT heat sink, filter inductors, DC-link capacitors, main control board, driver and sampling board, rear terminal block, rear ventilation grille, rack chassis housing and fixing hardware — GY-AHF series exploded view — 11 functional layers

01
Front Panel & HMI Interface
LCD display and membrane keys for on-site commissioning, parameter setting and live harmonic spectrum reading.
02
Front Air Vent Grille
Removable perforated grille with flame-retardant filter, giving uniform front-to-rear airflow across the power stack.
03
IGBT Heat Sink
Extruded aluminium heat sink with low thermal resistance, sized for continuous full-load operation at 55 °C ambient.
04
Filter Inductors
Three-phase output chokes that smooth the PWM current ripple and decouple the switching stage from the grid.
05
DC-Link Capacitors
Low-ESR electrolytic bank stabilising the DC bus and absorbing switching energy transients.
06
Main Control Board
Carries the dual DSP core, sampling circuitry and communication interfaces for Modbus and TCP/IP.
07
Driver & Sampling Board
Gate-drive isolation plus high-speed current and voltage sampling for the closed control loop.
08
Rear Terminal Block & Communication Interface
A/B/C/N power terminals sized for the rated current, together with RS485 and Ethernet ports.
09
Rear Ventilation Grille
Rear exhaust grille completing the forced-air cooling path of the rack chassis.
10
Rack Chassis Housing
Galvanised steel 19-inch chassis with front handles, providing mechanical rigidity and EMC screening.
11
Fixing Screws & Hardware
Stainless fasteners and mounting brackets for secure installation in standard cabinets.

MANUFACTURING & QUALITY CONTROL

Active filters are electronics, not sheet metal — so production quality decides service life. GY-AHF modules are built on the same lines as our SVG and capacitor control electronics, with inspection at every stage rather than only at the end.

Automated SMT line at the Gaoyun Electric factory: Solder paste printing, high-speed placement and reflow in a class-controlled electronics workshop. — **Automated SMT line**Solder paste printing, high-speed placement and reflow in a class-controlled electronics workshop.

Module assembly line at the Gaoyun Electric factory: Digital work instructions and material kanban at every station, so each unit is built to the same routing. — **Module assembly line**Digital work instructions and material kanban at every station, so each unit is built to the same routing.

Automated functional test at the Gaoyun Electric factory: Programmable power supplies and oscilloscopes verify input, output and waveform before potting. — **Automated functional test**Programmable power supplies and oscilloscopes verify input, output and waveform before potting.

In-line inspection at the Gaoyun Electric factory: Power modules on carriers move through staged inspection points along the assembly line. — **In-line inspection**Power modules on carriers move through staged inspection points along the assembly line.

Power stack assembly at the Gaoyun Electric factory: DC-link bank, forced-air cooling and busbars assembled and torque-checked on the line. — **Power stack assembly**DC-link bank, forced-air cooling and busbars assembled and torque-checked on the line.

Paired assembly lines at the Gaoyun Electric factory: Dual lines with AOI and in-line test stations keep capacity and traceability under control. — **Paired assembly lines**Dual lines with AOI and in-line test stations keep capacity and traceability under control.

Conformal coating at the Gaoyun Electric factory: Coating and dispensing station protects PCBA assemblies against humidity, dust and corrosive atmosphere. — **Conformal coating**Coating and dispensing station protects PCBA assemblies against humidity, dust and corrosive atmosphere.

Aging and packing at the Gaoyun Electric factory: Finished units run through aging racks, then are wrapped and palletised for shipment. — **Aging and packing**Finished units run through aging racks, then are wrapped and palletised for shipment.

SMT equipment control at the Gaoyun Electric factory: Placement machines are linked to the MES terminal for program and traceability control. — **SMT equipment control**Placement machines are linked to the MES terminal for program and traceability control.

Incoming material inspection→SMT + AOI→ICT / FCT→Full-load aging→Final inspection→Packing & traceability

Technical Specifications

GY-AHF model code explanation: GY company identifier, AHF series, 0.4 rated system voltage in kV, 100 rated compensation current in A, 4L/M three-phase four-wire rack-mount configuration

How to read the model code

Example GY-AHF-0.4/100-4L/M: GY = company identifier, AHF = Active Harmonic Filter series, 0.4 = rated system voltage 0.4 kV, 100 = rated compensation current 100 A, 4L/M = three-phase four-wire system in rack-mount (M) execution. Wall-mount versions use the suffix H.

Rack-mount models and enclosure dimensions

Model	Rated current	Dimensions L×H×D (mm)	Mounting size A×B (mm)
GY-AHF-0.4/30A-4L/M	30 A	500 × 100 × 645	472 × 50
GY-AHF-0.4/50A-4L/M	50 A	500 × 100 × 645	472 × 50
GY-AHF-0.4/75A-4L/M	75 A	500 × 180 × 666	472 × 95
GY-AHF-0.4/100A-4L/M	100 A	500 × 180 × 666	472 × 95
GY-AHF-0.4/150A-4L/M	150 A	500 × 200 × 666	472 × 95

Custom specifications and configurations are available on request.

Filtering performance

Function	Value
Harmonic filtering range	2nd – 50th order, individual setting per order
Harmonic attenuation	THDi reduced to below 5% at the point of common coupling
Reactive power compensation	Dynamic, capacitive and inductive, closed-loop
Three-phase balancing	Yes, simultaneous with harmonic filtering
Response time	< 5 ms
Overall efficiency	0.97
Parallel capability	Up to 10 modules, max. 1500 A system capacity

How to size a unit: measure the harmonic current of the load, not the total load current. Choose the module whose rated current is at least 1.15 × the measured harmonic current, then add parallel modules if the load grows. Our engineers verify the calculation against your CT ratio and grid impedance before shipment.

DIMENSIONS & CAD DOWNLOADS

GY-AHF 30 A and 50 A rack-mount unit dimension drawing, front view with length L, mounting width A, height H and depth D reference dimensions

30 A / 50 A — H = 100 mm

GY-AHF 75 A, 100 A and 150 A rack-mount unit dimension drawing, front and top view with length L, mounting size A and B, height H and depth D

75 A / 100 A / 150 A — H = 180 / 200 mm

Dimension note: terminal spacing varies with shell diameter for three-phase models. Always confirm the mounting size A×B against your cabinet's upright pitch before drilling.

The rack chassis follows the standard 19-inch footprint, so a GY-AHF module can share a cabinet with breakers, meters and controllers. For wall-mounted executions the suffix changes from M to H and the enclosure depth is reduced.

Need the drawing in a different format? The native DWG is available together with the complete dimension manual and the full datasheet.

2D CAD Drawing (DWG) Dimension Manual Full Product Datasheet (PDF)

CERTIFICATIONS

Gaoyun Electric operates a management system certified to three international standards. Certificates, scope statements and the latest audit reports are supplied with every quotation package.

ISO 9001

Quality Management System

Design, production and service of low voltage power quality equipment, audited annually by an accredited certification body.

ISO 14001

Environmental Management System

Controlled environmental impact across electronics assembly, coating, testing and logistics processes.

ISO 45001

Occupational Health & Safety Management System

Structured hazard control for production, high-voltage testing and site commissioning activities.

Product-specific test reports — including type test, temperature rise and EMC reports for the GY-AHF series — are available on request. Tell us the destination market and we will send the documentation set your authority requires.

SUCCESSFUL PROJECT CASES

Four reference projects show how the same hardware solves very different harmonic problems — a storage plant fighting grid-code limits, a PV farm protecting its inverters, a charging hub tripping breakers, and a machine shop losing production to PLC faults.

Case 1

Grid-tied Energy Storage Plant (BESS)

Pain point: Harmonics generated by PCS converters caused transformer overheating and frequent unexpected trips, with a real risk of grid-code non-compliance.
Solution: Several GY-AHF modules were installed on the low voltage bus to suppress harmonics in real time.
Result: THDi reduced from 32% to below 5%, transformer temperature dropped and the plant now fully complies with local grid codes.

Case 2

Large-scale Solar PV Farm

Pain point: Massive inverter output produced harmonics that interfered with monitoring instruments and accelerated cable ageing.
Solution: Rack-mounted GY-AHF units were deployed in the centralised distribution cabinets for dynamic harmonic compensation.
Result: Harmonic distortion brought under control, lower thermal loss and extended service life of inverters and cables.

Case 3

DC Fast Charging Station Cluster

Pain point: Nonlinear charging loads caused voltage distortion and unexplained breaker nuisance tripping.
Solution: A GY-AHF was installed in the main low voltage cabinet to track and compensate the variable harmonic spectrum.
Result: Stable continuous charging service, no random tripping, and the site now meets local utility power quality requirements.

Case 4

VFD & CNC Manufacturing Workshop

Pain point: Harmonics and three-phase unbalance from VFD loads caused PLC signal interference and frequent equipment faults.
Solution: GY-AHF provided integrated compensation of harmonics, reactive power and three-phase unbalance in one unit.
Result: PLC interference eliminated, equipment failure rate reduced and continuous stable production restored.

FREQUENTLY ASKED QUESTIONS

1. Can I customize the compensation current, voltage and cabinet size for GY-AHF?

Yes. We support OEM and ODM customization of rated voltage, compensation current, cabinet layout and communication protocol to match your project. Custom IP ratings and wall-mount execution are also available.

2. What harmonic orders can the GY-AHF compensate?

It suppresses harmonics from the 2nd to the 50th order, and each order can be enabled and weighted individually. Reactive power and three-phase unbalance are compensated at the same time.

3. How many units can be connected in parallel?

Up to 10 modules can operate in parallel. With the largest 150 A module this gives a system capacity of 1500 A, and modules can be added later without replacing the installed units.

4. What is the standard lead time?

7–10 working days for standard models; 15–20 working days for customized cabinets and special specifications.

5. What is the maximum operating altitude and ambient temperature?

Standard version: altitude up to 2000 m and ambient temperature from −25 °C to +55 °C. Above 2000 m the rated current is derated by 1% per additional 100 m. High-altitude and wide-temperature versions are available on request.

6. Do you provide overseas commissioning and technical guidance?

We offer remote online technical guidance worldwide. On-site commissioning is available for large turnkey projects.