Harmonics Analysis And Suppression Of Transformer Substation

With the massive development and application of high-power controllable silicon rectifiers and electric electron devices, as well as capacity increase of steel-making electric arc furnace and rolling mill, development and application of electrized railway, and the massive utilization of electricity-economical-type household and industrial electrical appliances, various non-linear loads render harmonics that input electricity grid gradually increase, thus seriously jeopardize the electricity quality and threaten the safety function of transformer substation devices. Harmonics control has become one of the most concerned issues for power supply departments.Starting from the actual necessities, this paper mainly presentsfollowing contents:1. the production of harmonics and the characteristics of various harmonics.2. the hazards of harmonics to transformer substation devices.3. the measures of harmonics control are systematically expounded.4. the classification of harmonics analyzers is presented. The effects of measuring algorithm and aperiodic weight on harmonics are analyzed. An improved algorithm is put forward. The harmonics theory is applied to electric harmonics real time monitoring system. The system is used to test and monitor harmonics in three transformer substations of Longlin, Shapo and Maling. The results show that electric harmonics real time monitoring system is reliable in function, high in measurement precision, and can meet the requirements of electricity quality spot analysis and monitoring.5. Through the analysis of actual metrical data of transformer substations, Longlin transformer substation, which is most seriously affected by electric harmonics, is selected as a case for analysis, the effects of harmonics on transformer substation is calculated, and the scheme of harmonics control is put forward. The actual function shows that the scheme of harmonics control has achieved the anticipative goal.