Evaluation of Dynamic Voltage Responses of Distributed Energy Resources in Distribution Systems

As the number of distributed energy resources (DERs) continues to increase, the DER response during a fault is becoming critical to power system stability. In the near future, DERs are expected to provide advanced functions such as voltage ride through and dynamic voltage support to maintain stable power system operation. In this context, an aggregated model of dynamic DERs that includes these advanced functions has been developed previously under the composite load model structure. In order to provide model parameters appropriate for an actual distribution system, however, dynamic simulations based on a detailed feeder model are required. Therefore, the purpose of this study is to evaluate the dynamic voltage response of a detailed feeder model incorporating modern DERs. In experiments on data from an actual circuit in California, the dynamic simulations reveal the partial loss behaviors of the DERs for several voltage sags, along with reactive current output induced by the dynamic voltage support.