Aggregation method for motor drive systems

作者：Liang Xiaodong^*; Xu Wilsun

来源：Electric Power Systems Research, 2014, 117: 27-35.

DOI：10.1016/j.epsr.2014.07.022

• Aggregation method
• Dynamic model
• Pade approximation
• Power system dynamic studies
• Transfer functions
• Variable frequency drives

When many variable frequency drives are connected to a common switchboard, their aggregated effect on system dynamics can be significant. In this paper, the aggregation method for variable frequency drives and their motors in industrial facilities is proposed, which is suitable for power systems dynamic studies. The proposed method can be applied to various types of motor drive systems. There are two steps involved for the proposed aggregation method: (1) aggregate motor drive systems connected to the same bus, and (2) further combine the aggregated model of motor drive systems from Step 1 with upstream series impedance and/or transformers. Due to involvement of high-order transfer functions in dynamic models of individual motor drive systems, Pade approximation is used as a useful tool in the aggregation process. Using the proposed aggregation method, an equivalent aggregated dynamic model of motor drive systems can be obtained at the substation bus. A case study is conducted in the paper, and the proposed aggregation method is verified to be effective by the case study.

• 出版日期2014-12