Risk assessment of power systems under a corrective control paradigm

Given the fact that the load is continuously growing as a sign of economic development and that renewable intermittent generation is growing rapidly driven by global climate change concerns and rising fuel costs, existing power systems need to be reinforced in order to accommodate the growing load and intermittent generation. Corrective control is a promising alternative solution to preventive control which, in this context, is represented by traditional system reinforcement of building more transmission facilities. The concept of reliability, existing reliability assessment methodologies and the latest development in this field were reviewed. The corrective control system was modelled as a common cause failure. New indices were derived and presented in the context of corrective control. They are Linear Weighed Reliability Index (LINWRI), Incremental Benefit of System Reinforcement (IBSR), Demand Response Incremental Cost Benefit (DRICB), and Voluntary Energy Curtailment Level (VECL).Three means of corrective control considered in this research are Demand Response (DR), Flexible AC Transmission Systems (FACTS) and Energy Storage (ES). One of the corrective control applications is the Active Management (AM) on distribution systems. The model of AM control system was developed and incorporated into chronological Monte Carlo simulation (CMCS). Different AM configurations and different reliability levels of AM with the same configuration have been proposed. Their impact on the ability to accommodate wind generation and on power system reliability was investigated. Economic assessment was also performed. A 'win-win' situation was achieved when a relatively reliable AM system is configured with Wind Generation Output Control (WGOC) function and the capacity of wind generation is adequate.DR models and the models of typical FACTS devices were reviewed and summarised. The Battery Energy Storage (BES) and Static Synchronous Compensator/BES (STATCOM/BES) models were developed based on the general structure of Energy Storage (ES) and a list of assumptions regarding their operation. Their models together with the model of the control system have been incorporated into CMCS which is applied as the reliability assessment methodology. The impact of DR, FACTS and ES on power system reliability was studied to a detailed level through test cases. The results have demonstrated the reliability improvement from corrective control compared to 'doing nothing at all' as well as the potential advantage of corrective control over traditional reinforcement in terms of cost effectiveness. The direction for future research related to this field was identified to be the investigation in network planning as an upstream project under a corrective control paradigm, the development of a more efficient and accurate nonlinear optimisation toolbox, the upgrade of DR models and FACTS models and the incorporation of transient analysis, etc.EThOS - Electronic Theses Online ServiceEngineering and Physical Science Research CouncilGBUnited Kingdo