The following PhD thesis presents challenges related to communication systems for data monitoring of distributed energy resources (DER). In recent years, we are witnessing the penetration of increased share of small-scale DERs, especially renewables (solar, wind, small-scale hydropower, etc.) into the evolving power system, which needs to be efficiently controlled, monitored and aggregated. In order to do so, advanced ICT-based concepts such as virtual power plants (VPP) are needed. Therefore, an overview of the VPP concepts and their engagement in the electric power system was conducted. This includes an exhaustive overview of the VPP communication systems architecture from several aspects.
However, to enable VPP concept, reliable communication systems for data exchange between all entities are fundamental. Their performance significantly impacts on the VPP service delivery, which is vital for cases when VPP participates in time critical process, for example balancing services. In the scope of our research, we focused on analysis of downstream communication between VPP system and DERs.
To investigate how communication system’s performance—more particularly communication latency, effects individual DERs activation and overall VPP service delivery, we developed a VPP behavioural model and performance simulation environment. For the development of the model, we used real measurements of VPP communication system performance of operational VPP deployment case studies utilised for the provision of balancing services. Methodology for measurement of VPP communication system performance, which we developed, is presented in the thesis.
The complete methodology comprises of method for measuring signal latency and method for
determining vital quality of service (QoS) parameters of VPP communication system. Both methods use network traffic captures and analysis as basis. Due to the specific configuration of each observed VPP deployment case studies (different DERs, communication technologies and protocols), we systematically analysed the measurement results conducted during the selected operational timeframes.
The measurement results—more particularly latency, were used as an essential input for the
development of analytical distribution models of latency, which are included in VPP behavioural model.
In the thesis, we investigated and evaluated the dynamic nature of the VPP by using numerical
simulations for the selected use cases to outline potential issues that could hinder successful delivery of balancing services.
Proposed methodology, analysis of measurements, modelling and numerical simulation results, which are the fruit of our work, bring important insights into the VPP communication systems behaviour.