Active Harmonic Filter (AHF)—Three Phase
Product Summary:
Active harmonic filters (AHF) are the ultimate answer to power quality problems caused by waveform distortions, low power factor, voltage variations, voltage fluctuations and load unbalance for a wide range of segments and applications. They are a high performance, compact, flexible, modular and cost-effective type of active power filters (APF) which provide an instantaneous and effective response to power quality problems in low or high voltage electric power systems. They enable longer equipment lifetime, higher process reliability,improved power system capacity and stability, and reduced energy losses, complying with most demanding power quality standards and grid codes.
AHFs eliminate waveform distortions from the loads like harmonics, inter harmonics and notching,and harmonic voltages caused by harmonic currents, by injecting in real-time the distorted current of same magnitude but opposite in phase in the electric power system. In addition, AHFs can take care of several other power quality problems by combining different functions in a single device.
Working Principle:
External CT detects the load current, DSP as CPU has advanced logic control arithmetic, could quickly track the instruction current, divides the load current into active power and reactive power by using the intelligent FFT, and calculates the harmonic content rapidly and accurately. Then it sends PWM signal to internal IGBT's driver board to control IGBT on and off at 20KHZ frequency. Finally generates opposite phase compensation current on inverter induction, at the same time CT also detects the output current and negative feedback goes to DSP. Then DSP proceeds the next logical control to achieve more accurate and stable system.


Technical Specifications:
TYPE | Series 400V | Series 500V | Series 690V |
Max neutral wire current | 15A、25A、50A、 75A、100A、150A |
100A | 100A |
Nominal voltage | AC380V(-20%~+20%) | AC500V(-20%~+20%) | AC690V(-20%~+20%) |
Rated frequency | 50Hz±5% | ||
Network | Three-phase three-wire/three-phase four-wire | ||
Response time | <40ms | ||
Harmonics filtering | 2th to 50th Harmonics,The number of compensation can be selected, and the range of single compensation can be adjusted | ||
Harmonic compensation rate | >92% | ||
Neutral line filtering capability | The filtering capacity of three-phase four-wire neutral line is 3 times of that of phase filtering | ||
machine efficiency | >97% | ||
Switching frequency | 16kHz | 12.8kHz | 12.8kHz |
Feature selection | Deal with harmonics/Deal with harmonics and reactive power/ Deal with harmonics and three-phase unbalance /Three options |
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Numbers in parallel | No limitation. A single centralized monitoring module can be equipped with up to 8 power modules | ||
Communication methods | Two-channel RS485 communication interface (support GPRS/WIFI wireless communication) | ||
Altitude without derating | <2000m | ||
Temperature | -20~+50°C | ||
Humidity | <90% RH,The average monthly minimum temperature is 25℃ without condensation on the surface | ||
Pollution level | Below level Ⅲ | ||
Protection function | Overload protection, hardware over-current protection, over-voltage protection, power failure protection, over-temperature protection, frequency anomaly protection, short circuit protection, etc | ||
Noise | <60dB | <65dB | |
Installation | Rack/wall hanging | Rack | |
Into the way of line | Back entry (rack type), top entry (wall-mounted) | Top entry | |
Protection grade | IP20 |
Product Appearance:
Rack-Mounted Type:


Model | Compensation capacity (A) |
System voltage(V) | Size(D1*W1*H1)(mm) | Cooling mode |
YIY AHF-50-0.4-4L-R(Compact) | 50 | 400 | 515*510*89 | Forced air cooling |
YIY AHF-75-0.4-4L-R | 75 | 400 | 546*550*190 | Forced air cooling |
YIY AHF-100-0.4-4L-R | 100 | 400 | 586*550*240 | Forced air cooling |
YIY AHF-150-0.4-4L-R | 150 | 400 | 586*550*240 | Forced air cooling |
YIY AHF-100-0.5-4L-R | 100 | 500 | 675*495*275 | Forced air cooling |
YIY AHF-100.69-4L-R | 100 | 690 | 735*539*257 | Forced air cooling |
Wall Mountedd Type:


Model | Compensation capacity (A) |
System voltage(V) | Size(D2*W2*H2)(mm) | Cooling mode |
YIY AHF-50-0.4-4L-W(Compact) | 50 | 400 | 89*510*515 | Forced air cooling |
YIY AHF-75-0.4-4L-W | 75 | 400 | 190*513*599 | Forced air cooling |
YIY AHF-100-0.4-4L-W | 100 | 400 | 240*600*597 | Forced air cooling |
YIY AHF-150-0.4-4L-W | 150 | 400 | 240*600*597 | Forced air cooling |
YIY AHF-100-0.5-4L-W | 100 | 500 | 275*495*675 | Forced air cooling |
YIY AHF-100.69-4L-W | 100 | 690 | 275*539*735 | Forced air cooling |
Floor Type:


Model | Compensation capacity (A) |
System voltage(V) | Size(D3*W3*H3)(mm) | Cooling mode |
YIY AHF-100-0.4-4L-C | 100 | 400 | Cabinet 1/Cabinet 2 | Forced air cooling |
YIY AHF-150-0.4-4L-C | 150 | 400 | Cabinet 1/Cabinet 2 | Forced air cooling |
YIY AHF-200-0.4-4L-C | 200 | 400 | Cabinet 1/Cabinet 2 | Forced air cooling |
YIY AHF-250-0.4-4L-C | 250 | 400 | Cabinet 1/Cabinet 2 | Forced air cooling |
YIY AHF-300-0.4-4L-C | 300 | 400 | Cabinet 1/Cabinet 2 | Forced air cooling |
YIY AHF-400-0.4-4L-C | 400 | 400 | Cabinet 1/Cabinet 2 | Forced air cooling |
YIY AHF-300-0.5-4L-C | 300 | 500 | Cabinet 1 | Forced air cooling |
YIY AHF-300-0.69-4L-C | 300 | 690 | Cabinet 1 |
* Cabinet 1 size: 800*1000*2200mm, can accommodate 5 modules.
* Cabinet 2 size: 800*1000*1600mm, can accommodate 3 modules.
* The table is the standard specification, if you need other sizes, pls contact us for customization.