关键词: 微电网, 孤岛和联网运行, 同步跟随, 平滑切换

Abstract:

Based on the microgrid system with photovoltaic（PV） generations, the smooth switching between the isolated island and the grid-connected operation mode is considered by this paper. Combined with the improved pre-synchronization controller, a smooth and synchronous tracking switching control method based on the initial output situation of the PQ controller determining the output situation of the V/f controller is established. The performances of the voltage-current double loop controller under given parameters are analyzed and calculated, which show that the method proposed is effective and the switching process is steady and rapid, satisfying the requirements of the smooth switching.

Key words: microgrid, isolated island and grid-connected operation mode, synchronous tracking, smooth switching