Contents I. Introduction
The word harmonic originates in acoustics and the mathematical analysis about the power harmonic has laid a good foundation in the 18th and 19th century. Harmonic analysis method which put forward by Fourier is still widely used. As the following presentation of the harm of harmonic, harmonic elimination has significant meaning for the improvement of the power quality[1].
The harm of harmonic is very serious. Harmonic makes the efficiency of electricity production, transmission and utilization low, electrical equipment overheating, vibration and noise, and the insulation aging, shorten the services life, even down or burned. It also cause local parallel or serial resonance power system which may destroy the devices.
Influence of harmonic on the development of power electronic technology. Power electronic technology is the important pillar of the future development of science and technology. Forecasters say power electronics become the most important technology in the 21 st century, together with the computer and motion control technology. Harmonic pollution, however, produced by the power electronic devices has become a significant obstacles hindering the development of the power electronic technology, it forces the researchers in this field of must study the harmonic problem more effectively.
Governance environmental pollution, maintain the green environment. For power system environment, Non-harmonic is one of the prime symbol for the “green”. In the field of power electronic technology, clamor for the implementation of “green power electronics” is also growing. At present, the protection of the earth's environment has become the consensus of all mankind. The management of the power system harmonic pollution has become a must solved problem of electrical science and technology.
