Description

active harmonic filter 

Introduction of Functions

Harmonic Filter: ETHF is composed of command current computing circuit and compensation current generating circuit. Command current computing circuit conducts real-time monitoring of current in circuit; switch the analogue current signals into digital signals, and send the signals into DSP for handling; separate harmonics and fundamental wave, send drive pulse in form of PWM signals to compensation current generating circuit; drive IGBT power module, produce compensation current input network which has the same amplitude as harmonic amplitude and inverse polarity; compensate or balance out harmonic current, eliminate power harmonics actively, and thus realize the dynamic quick and complement treatment of power harmonics.

Dynamic reactive power compensation:While filtering harmonics, according to detected need for reactive power compensation, HTQF command current computing circuit can control internal capative and inductive fundamental current of compensation current generating circuit, conduct real-time compensation, set the target value of reactive power compensation through operation board. There are 4 working modes for choice, namely, “filter priority”, “reactive power priority”, “harmonic filter only”, “and reactive power compensation only”. The working mode should be selected according to specific conditions of power distribution system.

Correct unbalanced 3 phases: HTQF can compensate the unbalanced 3 phases respectively. It can conduct phase adjustment of active power through DC Energy Storage Systems shared by 3 phases, thus to correct unbalanced load of 3 phases. The operation of this function can also be set by operation board.

Special Features

Higher efficiency, lower loss

       Patented technology of ripple cancellation and stagger converter is characterized by high current tracing speed, small ripple and low loss;

   Multi-DSP collaborative control can guarantee highly accurate control and high-speed computation;

   The harmonic filter rate is high. Toward target harmonics, effective harmonic filter rate can reach *7%;

   It can filter up to over *0 kinds of harmonics at the same time, and harmonics in side of the *0th at most

   Low-loss ceramic alloy;

 Magnetic Core reactor is characterized by low noise and high efficiency.

More functions, more modes

  Fractional compensation of harmonics can be set according to actual needs;

  Harmonic reactive compensation is equipped with 4 working modes, namely, “filter priority”, “reactive power priority”, “harmonic filter only”, “reactive power compensation only”, which can satisfy the compensation need for various power distribution systems;

  Balance compensation function can balance the load current among phases;

  RS**5 interface, standard MODBUS RTU communication protocol, and computer remote monitoring function.

More stable, more reliable

l      Optical fiber drive can guarantee high security, reliability and anti-jamming capability;

l      Multi-protection, strict thermal design can ensure the secure and reliable operation of the system;

l      Advanced control algorithms can offer stable operation for various complex environments, and it can also conduct parallel operation with capacitor compensating box;

l      Digital control, LCD working platform Chinese;

l      Self-diagnosis function

l      Record of historical events function

Higher power density, easier installation and maintenance

l      Modular design of converter can guarantee high power density, and easy installation and maintenance;

l      Output capacity is high. Single-unit output capacity can reach up to **0A;

l      It can conduct multi-machine parallel operation to satisfy various needs for compensation capacity.

l      Automatic current limiting will be conducted once output capacity is fully loaded,  so it is free of the trouble in overloading;

l      Detection methods of source current and load current are optional for the convenience of field installation.

Technical parameter