Fault model of IIDG considering LVRT and its application in fault analysis of active distribution networks

According to the low voltage ride through (LVRT) requirement stipulated by the distribution grid standards, an LVRT strategy based on reactive power support of the inverter interfaced distribution generation (IIDG) was first presented. The maximum energy output, which achieves the optimal efficiency of distributed power supply, was also taken into account. Then the fault characteristics of IIDG with LVRT strategy were analyzed. Considering the impact of LVRT controlled IIDG on power distribution, the short circuit current analysis is discussed and a short circuit calculation model of distribution networks with IIDG was established. Case study in Digsilent shows the effectiveness of the LVRT strategy and the fault calculation method.