Active Harmonic Filters (AHF) An active harmonic filter is a type of electronic device that is used to mitigate or eliminate harmonic distortions in electrical power systems. Harmonic distortion refers to the presence of unwanted frequencies in the power system that can lead to issues such as increased heating of equipment, reduced system efficiency, and even equipment failure.
AHF operates by sensing the harmonic currents in the system and generating a counter-current of the same magnitude and opposite phase. This counter-current cancels out the harmonic current and prevents it from being fed back into the power system. Active harmonic filters are designed to be fast and accurate in their response to changing harmonic conditions in the power system.
Active harmonic filters are commonly used in industrial and commercial settings where there are high levels of non-linear loads, such as variable frequency drives, uninterruptible power supplies, and computer equipment. They are also used in power quality improvement applications in residential and commercial buildings.
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.
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TYPE |
Series 220V |
Series 400V |
Series 500V |
Series 690V |
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Max neutral wire current |
23A |
15A、25A、50A、 |
100A |
100A |
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Nominal voltage |
AC220V(-20%~+20%) |
AC380V(-20%~+20%) |
AC500V(-20%~+20%) |
AC690V(-20%~+20%) |
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Rated frequency |
50Hz±5% |
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Network |
Single phase |
Three-phase three-wire/three-phase four-wire |
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Response time |
<40ms |
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Harmonics filtering |
2th to 50th Harmonics,The number of compensation can be selected, and the range of single compensation can be adjusted |
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Harmonic compensation rate |
>92% |
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Neutral line filtering capability |
/ |
The filtering capacity of three-phase four-wire neutral line is 3 times of that of phase filtering |
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machine efficiency |
>97% |
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Switching frequency |
32kHz |
16kHz |
12.8kHz |
12.8kHz |
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Feature selection |
Deal with harmonics |
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Numbers in parallel |
No limitation. A single centralized monitoring module can be equipped with up to 8 power modules |
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Communication methods |
Two-channel RS485 communication interface (support GPRS/WIFI wireless communication) |
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Altitude without derating |
<2000m |
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Temperature |
-20~+50°C |
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Humidity |
<90% RH,The average monthly minimum temperature is 25℃ without condensation on the surface |
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Pollution level |
Below level Ⅲ |
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Protection function |
Overload protection, hardware over-current protection, over-voltage protection, power failure protection, over-temperature protection, frequency anomaly protection, short circuit protection, etc |
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Noise |
<50dB |
<60dB |
<65dB |
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Installation |
Rack/wall hanging |
Rack |
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Into the way of line |
Back entry (rack type), top entry (wall-mounted) |
Top entry |
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Protection grade |
IP20 |
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