Modelling and simulation of wind energy systems with reserves margin in a deregulated electricity market

Abstract

One of the two major uncertainties that a power company must deal with is the potential that the load may be much higher than expected owing to a variety of variables, including weather. On the other hand, utility generation units may experience forced or unexpected outages, reducing the amount of power available overall. Utilities have a reserve margin to take these uncertainties into account. The amount of available but unutilized generating capacity during periods of peak demand is known as the reserve margin. The ideal reserve margin is determined by a load-serving entity's size and composition. Operating reserve margin from renewable energy sources has been studied in light of the significant increase in the production of electricity from such sources as solar and wind. Although wind energy production has increased dramatically in recent years, much more research is still needed to understand how it might be used to provide operating reserves. This research study highlights the effects of keeping an optimum operating reserve margin on factors such as the stability of the grid. This study also looks at the possibility of using wind energy systems to create active power operating reserve margins taking into consideration their intermittent nature. Owing to the intermittent nature of wind energy, it is also suggested to use a battery energy storage system to provide active power when the wind energy system is limited. This study makes use of the IEEE 9 bus power system concept, which is modelled using Real-time Simulation Computer-Aided Design (RSCAD), a simulation program. The RSCAD simulation tool is used to model a wind energy system (WES) and a battery energy storage system (BESS), which are then connected to the grid to provide the necessary active power operational reserves. When wind farms are connected to energy storage devices, such as batteries, excess wind energy can be stored for use in high-generation periods and released for use in seasons of high demand or low wind availability. As a result, wind energy is more dependable and contributes more to the reserve margin. Active power control for the involvement of the battery energy storage system and the wind energy system in the provision of active power operational reserves was designed using the RSCAD simulation program. This study develops an active power control algorithm with a WES and a BESS. Section 5.4, subsection 5.4.1, in Chapter 5 contains the development of the control algorithm. Following the active power control loop's development, Case Studies 1, 2, and 3 were simulated. This study also models, simulates, and analyses the South African power systems network with wind, and battery models with allocated reserve margin. Conduct detailed electricity market investigations with different case studies in the RSCAD software suite for the RTDS simulation package. The result analysis of the simulated case studies shows that the developed active power control loop is effective in restoring grid stability by dispatching the required active power from both the WES and BESS. In deregulated power networks, wind energy systems can efficiently maintain the reserve margin, improving grid stability and reliability and accelerating the shift to cleaner, more sustainable energy sources. Extensive and systematic literature reviews were conducted, and the theoretical aspects of the topic were also considered. The Real-time digital Simulator Computer-Aided Design (RSCAD) simulation software was used to perform the model and simulations as described in the chapter. The academic and industrial contributions of the research work are highlighted, along with future considerations for advancing the work. Additionally, publications such as journals and conferences are mentioned, and a list of references consulted for this dissertation is included in this thesis.