スコット結線変圧器による分散型電源連系時の配電系統内三相不平衡抑制効果の一考察

抄録

The diffusion of the dispersed power generation systems has been expected against the global environmental issue, the resources problem, and the energy security. The dispersed generators for residential use are connected to the low voltage distribution line, which can cause three-phase unbalance in the middle voltage distribution line. The three-phase unbalance leads to less performance of the grid system and inefficient operation of the three-phase electrical equipment.
In the AC traction system, Scott-transformer, which has a simple configuration and can suppress three-phase unbalance caused by the single phase loads, has been used for three-phase unbalance compensation.
In the previous study, the simulation results showed that the Scott-transformer could reduce the three-phase unbalance in the distribution system with dispersed generators. In the simulation, the dispersed generators were given as an ideal current source with a fixed amplitude and a phase angle. In this study, the current source feeds an AC current synchronized with the grid voltage at the connection point with power factor 1.0, and adjusts the amplitude to supply a constant output power. The effects of Scott-transformer for three-phase unbalance have been confirmed in the simulation as well as the previous study.