The general idea of ??harmonic governance. Harmonic governance should first consider the prevention, control source good harmonic generation, harmonic control, so that the harmonic generated in the system to minimize, you can more easily control or do not have further treatment. Therefore, the choice of equipment and building systems, it should be reduced harmonics as an important condition to consider. For AC and DC communication power supply equipment into two categories: under other conditions the same or a similar situation, UPS system should give priority to 12 pulses or equipment Delta transform the DC system should prefer better rectifying circuit and improve filtering measures The product. Secondly, on the basis of prevention, to consider remedies. Especially for the low-pressure system existing users, because the system has been basically fixed structure, harmonic problems can only be solved through the installation of the reactor control, filters and other remedies. The main structure is a passive filter of a reactor and a capacitor connected in series to form the LC series circuit, connected in parallel to the system, LC resonant circuit frequency is set on the need to filter out the harmonic frequencies, such as the 5th, 7th, 11 times the resonance point, to filter out the object of this 3rd harmonic. 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, harmonic control sales, the majority of low-voltage 0.4KV system using passive filtering methods, the role of harmonic control cabinet, high voltage 10KV almost all this way to harmonic governance. Because of China's SMEs are mostly private, fee harmonic control, the owners lack of knowledge of the harmonic harm, 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 reactive power requirements and very strict, we must reach a fine. Therefore, the owners had to ask for filtering. Thus, the market outlook considerable economic benefits also substantial. Harmonic manufacturers, learning Connaught Electrical and Mechanical, harmonic control by learning Connaught Mechanical and Electrical Equipment Co., Ltd., Henan. Henan Xi Connaught Electrical Equipment Co. (www.hnxinuo.com) located in the south China city of Zhengzhou Area 6B 6B-3-342. Scraps and development in the wave of market economy, the current study Connaught Electrical and Mechanical has a high profile in the electronics, electrical products processing, enjoys a good reputation. Xi Connaught Electrical and Mechanical made whole network business alliance certification, marking our service and management level has reached a new height. Xi Connaught Electrical and Mechanical staff is willing to joint development with all people a better future.