The main structure is a passive filter of a reactor and a capacitor connected in series to form the LC series circuit, harmonic control cabinet prices, parallel to the system, LC resonant frequency of the circuit is set in the need to filter out the harmonic frequencies, The method of harmonic control, such as the 5th, 7th, 11 times the resonance point, to filter out these 3rd harmonic purposes. Its low cost, but the filtering effect is not very good, if the resonance frequency is set properly, will resonate with the system. Filtering take more circulation on the market is this one, mainly because of low cost, easy for the user to accept. Although poor filtering effect, as long as the state limits for harmonic and reactive power sector requirements on the line. Because of its low cost, there is a large market demand, in general, the majority of low-voltage 0.4KV system using passive filter system, high pressure 10KV almost always this way for harmonic control. China's SMEs due to lack most are private owners of harm harmonic understanding, harmonic control, generally reluctant to come up with a lot of money to control harmonics, while some enterprises due to the harmonic content is too large, conventional reactive power compensation can not work unless the electricity sector of the reactive power requirement is very strict, it must reach a fine. Therefore, the owners had to ask for filtering. Thus, the harmonic control vendors, its considerable market prospects, economic benefits also substantial. Common market by testing electrical harmonic situation, we understand the current harmonic pollution me very serious domestic industries, especially the early years to save energy, the introduction of variable frequency power supply and DC electrical inputs, the 5 , 7th, 11th harmonic current content accounted for 20%, respectively, fundamental, 11%, 6%, which for small power users, not how, but for power users, harm it great, for intermediate frequency furnace users, it uses a conventional reactive power compensation can not be carried out, some users with a conventional capacitor reactive power compensation, can not be put into the capacitor, and some even put in, but also to the 5th harmonic current amplification of more than 1.8 to 3.8 times, making motors, transformers and other electrical copper loss, iron loss greatly increased, shortening the life of the equipment, pay more for electricity. What is Harmonic | Harmonic | By Henan Xi Xi Connaught Electrical and Mechanical and Electrical Equipment Co. Connaught. What is Harmonic | Harmonic | Xi Xi Henan Connaught Connaught Electrical and Mechanical and Electrical Equipment Co. (www.hnxinuo.com) this year introduced a new upgrade, the above picture is for reference only, please call the contact or pictures on this page phone, for the latest information, contact: Yang Yongjie.