Capacity assessment of distributed generations considering operational risks in distribution network

摘要

The shortage of traditional fossil energy and intensified ecological deterioration have made the utilization of renewable energy become an irresistible development trend and a global consensus. High penetration rate of distributed generations (DG) and the significant uncertainty of their output power pose a certain risk to the safe and stable operation of distribution networks, and the optimal capacity configuration needs to be further studied. This paper aims to establish a model to maximize the capacity penetration of DG considering operational risks. Probabilistic load flow based on the cumulant method is applied to deal with the randomness of wind power and load demand. On this basis, indices of node overvoltage risk (ROV), node undervoltage risk (RUV), and line overload risk (RLO) are established to assess the risk level of the distribution network. Then an optimal planning model which intends to maximize the penetrated capacity of wind power is presented considering multi-risk factors. The case study is conducted on the modified IEEE 33-bus radial test system and the results reveal that the proposed strategy is effective and practical.