APF Technical Principle
Active power filter (APF/AHF) is new power electronic equipment which can dynamically filter harmonic with variable amplitude and frequency and compensate reactive power, it overcome the shortages of conventional LC filter and obtained the better compensation performances than passive filter.
The right diagram is schematic diagram of active power filter (APF/AHF), where, Vs is AC power supply, nonlinear load is harmonic source, it generates harmonic and consumes reactive power. APF system is composed of instruction current operational circuit and compensation current generation circuit, the instruction current operational circuit is mainly to detect current components in harmonic current and reactive power of compensation object, and the compensation current generation circuit generates equivalent compensation current with same amplitude and inverse polarity with harmonic current to filter harmonics according to instruction signal, the main circuit adopts PWM converter.
APF Functions
Reduce harmonic distortionImprove power factorReduce line lossPrevent neutral line from overheatPrevent power equipments from noise, overheat and vibration like motor, transformer etc.Prevent signal transmission equipments from data loss and interferencePrevent measurement error caused by non-sinusoidal current and voltage.Prevent sensitive semi-conductive device from damagePrevent circuit breaker trip.Prevent capacitors from burn due to harmonic resonanceEnsure safety of power system and reduce energy consumptionAPF Technical Features
Can filter all kinds of harmonic currentsFiltering capability >95% for aimed harmonicTraction level IGBT module, 20KHz switching frequency Response time <10msSingle capacity up to 300ASuppress three-phase unbalanceConform to IEEE Std. 519-1992, GB/T 14549Can be used as harmonic sourceApply closed-loop control, and ensure filtering accuracy Can set filtering mode and select harmonic filtering typeAdapt automatically to impedance change of power network Can connect 690V system(CE/C-tick) and 600V system(cUL) directlyParallel connection, easy for filtering capacity expansionModularized design, easy for maintenancePerfect protection functionsFaults record and history inquireSupport multiple communication protocolsTechnical Parameters
SN | Parameters | Value |
1 | Power Supply Voltage(kV) | 0.4/0.69kV (±15%) |
2 | Power Supply Frequency (Hz) | 50/60Hz |
3 | Power Supply Mode | Three-phase three wires or three-phase four wires |
4 | Harmonic Compensation Components | 2~50 |
5 | Response Time (ms) | <10ms |
6 | Output Current(A) | 25~750A |
7 | Protection Mode | Over current, overheat, phase loss, Error-phase, DC busbar over/under voltage, Current limit for overload etc |
8 | Loss | <5% |
9 | Operation Display | Touch screen |
10 | Operation Environment | -100C~+450C |
11 | Altitude | <1000m |
12 | Relative Humidity | <90% (250C) |
13 | Noise | <70Db |
14 | Compensation capability | All within compensation capacity |
15 | Compensation Mode | Harmonic compensation, reactive power compensation or Both |
16 | Switching Frequency | 20kHz |
17 | Cooling Mode | Forced air cooling |
18 | IP | IP20 |
19 | Color | RAL7032 |
20 | Feed Direction | Top/Bottom |
21 | Communication | RS485/RS232 |
Factory Acceptance Test Platform
We built the first-class high voltage and big capacity active power filter test platform to realize Factory Acceptance Testing for whole machine before delivery.
Model and Dimension
Model | Output current(A) | Dimension(W×D×H)mm |
WLD-APF-0.4-75-3L WLD-APF-0.4-75-4L | 75 | 800×600×2200 |
WLD-APF-0.4-150-3L WLD-APF-0.4-150-4L | 150 | 800×800×2200 |
WLD-APF-0.4-225-3L WLD-APF-0.4-225-4L | 225 | 800×800×2200 |
WLD-APF-0.4-300-3L WLD-APF-0.4-300-4L | 300 | 1200×1000×2200 |
WLD-APF-0.4-375-3L WLD-APF-0.4-375-4L | 375 | 1600×800×2200 |
WLD-APF-0.4-450-3L WLD-APF-0.4-450-4L | 450 | 1600×800×2200 |
WLD-APF-0.4-525-3L WLD-APF-0.4-525-4L | 525 | 1600×800×2200 |
WLD-APF-0.4-600-3L WLD-APF-0.4-600-4L | 600 | 2400×1000×2200 |
WLD-APF-0.4-675-3L WLD-APF-0.4-675-4L | 675 | 2400×1000×2200 |
WLD-APF-0.4-750-3L WLD-APF-0.4-750-4L | 750 | 2400×1000×2200 |
The above dimension is our standard cabinet for 400V APF (Active power filter) and the wall-mounted cabinet or other voltage level APF can be designed according to requirements of users.
Wanlida Active power Filter/50A~600A