A virtual power plant (VPP) is formulated and developed as a service-centric aggregator that enables the market integration of distributed energy resources and simultaneously supports cooperation with the distribution system operator in addressing the issue of network usage. A suitable schedule of interactions and communications between aggregators, market operators, system operators, generators, and consumers, regarding electricity market participation and network operation is proposed and presented in a sequence diagram. The cooperation on congestion management in the distribution network is highlighted as a solution to relieve network constraints via the optimal adjustment of active and reactive power of VPP resources while maximizing renewable energy integration across the pool under management. The VPP reduces uncertainty affiliated with input data by employing the latest forecasts through a rolling horizon approach in the planning stage. Thanks to the flexibility of the VPP to perform rescheduling in accordance with agreements it negotiated with its resources, it becomes possible to refrain from undesirable curtailments. Both the market-integrative and the service-centric roles of the VPP are verified through modeling and simulation with a benchmark European distribution network. The results confirm the added value of the proposed VPP in enhancing the integration of wind and solar power.

This paper summarizes the report prepared by an IEEE PES Task Force. Resilience is a fairly new technical concept for power systems, and it is important to precisely delineate this concept for actual applications. As a critical infrastructure, power systems have to be prepared to survive rare but extreme incidents (natural catastrophes, extreme weather events, physical/cyber-attacks, equipment failure cascades, etc.) to guarantee power supply to the electricity-dependent economy and society. Thus, resilience needs to be integrated into planning and operational assessment to design and operate adequately resilient power systems. Quantification of resilience as a key performance indicator is important, together with costs and reliability. Quantification can analyze existing power systems and identify resilience improvements in future power systems. Given that a 100% resilient system is not economic (or even technically achievable), the degree of resilience should be transparent and comprehensible. Several gaps are identified to indicate further needs for research and development.

The intermittency of renewable energy sources makes the use of energy storage systems (ESSs) indispensable in modern power grids for supply-demand balancing and reliability enhancement. Besides pumped-storage hydroelectric power stations, energy storage deployment worldwide is still quite low. However, the status quo might rapidly change as the energy storage technologies are growing and facilitating market regulations are being ratified. Battery energy storage systems (BESSs), Li-ion batteries in particular, possess attractive properties and are taking over other types of storage technologies. Thus, in this article, we review and evaluate the current state of the art in managing grid-connected Li-ion BESSs and their participation in electricity markets. The review mainly includes battery modeling, the architecture of battery management systems (BMSs), the incorporation of BESSs for electricity market services, global utility-scale battery storage facilities, and challenges in implementing and managing grid-connected BESSs.

Microgrids are subsystems of the distribution grid operating as a single controllable system either connected or isolated from the grid. In this paper, a novel cooperative model predictive control (MPC) framework is proposed for urban districts comprising multiple microgrids sharing certain distributed energy resources (DERs). The operation of the microgrids, along with the shared DER, are coordinated such that the available flexibility sources are optimised and a common goal is achieved, e.g., minimizing energy exchanged with the distribution grid and the overall energy costs. Each microgrid is equipped with an MPC-based energy management system, responsible for optimally controlling flexible loads, heating systems, and local generation devices based on end-user preferences, weather-dependent generation and demand forecasts, energy prices, and technical and operational constraints. The proposed coordination algorithm is distributed and guarantees constraints satisfaction, cooperation among microgrids and fairness in the use of the shared resources, while addressing the issue of scalability of energy management in an urban district. Furthermore, the proposed framework guarantees an agreed cost saving to each microgrid. The described method is implemented and evaluated in a virtual testing environment that integrates accurate simulators of the microgrids. Numerical experiments show the feasibility, the computational benefits, and the effectiveness of the proposed approach.

In accordance with European plans, dynamic controls are developed to allow for system-wide integration of 100 % renewable energy sources (RESs) interfaced through power electronic converters while maintaining security. At the heart of the development is the concept of the grid-forming resource (GFR) which brings together both the technologies of renewable energy resource and grid-forming converter. Extending on an extensive review, a grid-forming converter control and protection scheme is presented to ensure operation under small-and large-signal transients as needed for overall system security. The scheme is shown to be practical in offering inertial response emulation and frequency control based on droop characteristics to maintain power balances rapidly, to control voltages, as well as to support transient stability enhancement under grid faults. The integration with the control of wind energy conversion systems (WECSs) creates a grid-forming wind park as the prototype of the GFR. Feedforward signals exchanged between grid and resource-side controls enhance fast overall controllability. The principal claims are substantiated based on a scenario developed in the European project initiative MIGRATE with a focus on the Irish power transmission system. The model comprises more than 2000 individual WECSs grouped into wind parks, where ten wind parks are GFRs. The transient behavior of this scenario comprising 100 % converter-interfaced generation is shown to be superior compared with a counterpart case comprising synchronous machinery. The results validate the fact that GFRs with their proposed controls are expected to be key elements in creating a renewable and secure electric power system.