Performance evaluation of a virtual power plant communication system providing ancillary services

Virtual power plants are an integral part of advanced power systems providing different ancillary services. This paper presents a case study of an operational virtual power plant communication system providing manual Frequency Restoration Reserve service to the transmission system operator, aggregating two Distributed Energy Resources: a refinery facility with steam turbines and diesel generator sets, and a paper mill plant with an available flexible capacity of 30 MW in total. The study is based on the communication traffic data captured during the virtual power plant live operation over a one-month period with fourteen fully automatic activations. The study analyzes selected communication quality of service parameters-in particular, latency, packet loss, retransmissions, bandwidth, amount of traffic, and message patterns of the IEC 60870-5-104 protocol.