Power quality problem and key improvement technology for regional power grids.

In this paper, the status quo, analytical methods, and treatment technologies of steady-state power quality problem with the largest influential degree and range are reviewed. Typical harmonic sources in regional power grids and their characteristics are investigated, the influence of harmonics on a regional power grid is described, and the main harmonic control measures including active and passive types are introduced. The sources, status quo, and adverse effect of the three-phase imbalance problem of regional power grids are examined. Meanwhile, relevant standards and imbalance calculation methods are introduced. The operation measures and treatment equipment for solving the three-phase imbalance problem are also presented. The status quo, mechanism, and danger of low voltage (LV) in regional grids are analyzed as well as the LV monitoring methods, and the corresponding treatment technologies are summarized. Finally, the key to treating the steady-state power quality of regional power grids is proposed. [ABSTRACT FROM AUTHOR]