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This paper forcuses on the preliminary investigation of Hybrid Power Plants (HPPs) operation in balancing market in 2030. The opportunities of balancing market are firstly analyzed. The the 2030 market information is simulated by balancing tool chain. Spot market optimization and balancing market optimization are introduced sequentially. For balancing market optimization, a scenario based stochastic optimization is applied to deal with the forecast errors of regulation price. By leveraging multi-price scenarios, the objective foundation is to maximize expectations of profits. In case study, market scenario of 2020 and 2030 are compared firstly. After that, we define two cases to simulate HPP operation in 2030. The case when HPP only participates in spot market is designed as a benchmark case to evaluate the value of balancing market. The investiagtion assumes an HPP located in West Denmark (DK1) and therefore applies the market rules for this area. Simulation results demonstrate that HPP can receive 11% increase of revenues in balancing market, but due to the high degradation cost of battery, the profit increase is 5,9%.

The increased penetration of weather-dependent distributed generation, such as wind power plants and photovoltaics, in distribution networks, presents new challenges for the distribution system operators to improve their networks’ operation by effectively utilizing the available resources. A higher amount of distributed generation also directly translates to more power losses in the network. In this regard, wind power plant capabilities can prove valuable to avoid network congestion, maintain supply and reduce network losses. This paper aims to minimize losses in distribution networks with a large share of wind power plants by optimizing the reactive power flow through the distribution networks by controlling reactive power set-points of wind power plants using genetic-algorithm based optimization. The study is conducted on a real Danish distribution network, with a large share of controllable wind power plants, under varying wind and load conditions using actual measurements. The results show that the reactive power support from wind power plants can reduce network losses by ≈ 2.5 % (103 MWh) with a 0.25 % uncertainty in the mean loss reduction. However, the uncertainty in loss reduction depends on the loss in the network without using wind power plant capabilities. This work successfully demonstrates that the control capability of wind power plants can support distribution system operators by reducing losses in distribution networks.

Power distribution systems with a high share of Variable Renewable Energy Sources (VRE) face problems due to the variability, uncertainty, and non-dispatchable nature of VRE. This paper reviews and discusses the pertinent challenges arising for steady state operation of future distribution systems with a large share of weather-dependent renewable energy sources. The substantially increased amount of VRE in future distribution networks transforms them into highly weatherdependent networks with limited real-time observability. Challenges of such networks, like sustained over-voltage, increased power losses in the network, growing stress upon the existing network assets and changing interactions with the upstream grid, are addressed in the paper. Illustrations from past research and practical demonstrations of these challenges are presented to emphasize the severity of the problems.

This paper presents the modelling and the control architecture of two different hybrid power plant topologies, e.g. AC and DC coupled Wind-Solar-Storage based Hybrid Power Plants. Dynamic models of different individual assets are briefly described in the paper. A set of simulations are carried out in order to verify and demonstrate the performance of the dynamic models and of the hybrid power plant control dispatch strategy for different control functionalities - namely, maximum power point tracking, delta control and balance control. An overview of the modelling challenges and complexities of ancillary services provisions from hybrid power plants is provided and discussed.

Nowadays, most of the ancillary services such as reserve capacity, inertia and frequency control relies on large conventional power plants. Approaching future power systems with high penetration of renewable energy sources (RES) has resulted in imperative need for the evaluation of ancillary services. This research focuses on the frequency stability which must be ensured in order to maintain the grid stability against imbalances between generation and load. This large conventional power plants that provide ancillary services are called “must-run” units. These facilities are generation power plants necessary during certain operating conditions and they are responsible for providing enough ancillary services to ensure a reliable operation of power systems. Given a high RES penetration in the future, must-run units are expected to be reduced or totally decommissioned reducing the power system inertia. This may result in insecure operation threatening the reliability of the power supply. This project investigates the frequency stability support from renewable energy generation such as wind power plants (WPPs) and solar photovoltaic systems (SPVSs) in future power systems with high penetration of RES and without must-run units. Sensitivity studies for frequency stability are performed on a simulated 2030 scenario for western Denmark (DK1) power system. The objective of this master thesis is to study the DK1 power system to analyse the ability of modern controllable WPPs to provide frequency stability without must-run units in a future scenario dominated by RES generation. This project examines the primary frequency control in DK1 simulating an overfrequency event islanding DK1 from the CE power system with high wind forecast. The main results of this project reveal that the fast deploy of active power by the RES generation counterbalances the reduced inertia in the power system, which can operate without a lack of stability of the power supply for overfrequency events wi