王子昂,孟润泉,韩肖清.微电网与配电网间串联补偿变压器直流偏磁抑制策略研究[J].电测与仪表,2022,59(1):127-133. Wang Ziang,Meng Runquan,Han Xiaoqing.Research on DC bias suppression strategy of series compensation transformer between micro-grid and distribution network[J].Electrical Measurement & Instrumentation,2022,59(1):127-133.
微电网与配电网间串联补偿变压器直流偏磁抑制策略研究
Research on DC bias suppression strategy of series compensation transformer between micro-grid and distribution network
By adding a series link between the AC/DC hybrid micro-grid (HMG) and the distribution network, when the AC/DC HMG is connected to the grid, the power quality and traversing ability of the distribution network in the event of a fault can be achieved. At the beginning of a fault in the distribution network, the series compensation transformer (SCT) in the series link is prone to produce a DC bias phenomenon and affect power quality. This problem is usually solved by designing the SCT core at twice the rated value, but this will greatly increase the size and cost of the SCT. In order to ensure the reliable, stable and safe operation of the series link between the AC/DC HMG and the distribution network, and to reduce the size and cost of the SCT, it is necessary to suppress the DC bias of the SCT. Based on the analysis of the principle of SCT DC bias, a DC bias suppression strategy is proposed by controlling the amplitude of the first half cycle of the output voltage of the series link. Joint simulations are performed in Simplorer, Matlab, and Maxwell. Combined with the experimental results, the SCT DC bias is effectively suppressed, which verifies the feasibility and effectiveness of the proposed suppression strategy.
