On some aspects of frequency regulation market design and analysis

Abstract

To maintain the real-time balance of power generation and load, it is necessary to procure frequency regulation services in the power system operation. During past two decades, the growing integration of intermittent renewable energy sources has brought more uncertainties to grid operation, enhancing the need for high-performance regulation services. Energy storage systems have extensive applications in today’s power system operation. Among all types of energy storage systems, energy-limited and fast-responding storage devices including battery energy storage, flywheel energy storage, superconducting magnetic energy storage, and super-capacitor energy storage can provide high-performance regulation services due to their fast ramping capability and controllability. However, traditionally, regulated systems do not distinguish high-performance frequency from the rest. There is a lack of incentives for fast-ramping units to provide regulation Therefore, it is necessary to adjust the frequency regulation market design to encourage devices/units with better regulation performance to participate in the market. A frequency regulation market model considering regulation performance is proposed in this thesis. In the proposed market, both regulation capacity constraints and regulation mileage constraints are satisfied. Fast-ramping regulation units have higher priorities to be cleared in providing regulation services. Market clearing prices are derived with Lagrange relaxation. The analysis of the components of market clearing prices accurately indicates the relationship between regulation capacity and mileage. In response to the performance-based regulation market model, an adjusted AGC allocation method is proposed. The numerical results show that the proposed market model could give incentives to fast-ramping storage units to provide regulation and these resources could be deployed appropriately in real-time operation with the modified AGC allocation method. Next, to investigate the relationship between the prices of energy and regulation products, energy and performance-based regulation are obtained simultaneously in an OPF-based market model considering the participation of energy storage units. In the proposed market model, the generation schedule of thermal units, charging and discharging status of energy storage units and the commitment of regulation resources are determined. The proposed market model is tested to verify the validity. The numerical results demonstrate that energy storage devices could be used to provide both regulation and energy. With the implementation of a performance based regulation market, fast-ramping energy storage units may become price-makers and manipulate market clearing prices by strategically bidding. Therefore, a framework to analyze the market power issues from the perspective of the system operator is proposed. The market power held by each regulation resource is quantified. Regulation market power indices are developed to evaluate the market power held by individual regulation resource, a regulation provider, and the whole system, respectively. The numerical studies on illustrative case and the IEEE 39-bus system verify the effectiveness of the proposed method. Several applicable suggestions are introduced to mitigate the potential abuse of market power. In summary, studies in this thesis have covered review, design, and analysis of the frequency regulation market. These studies provide tools for system operators and market regulators to enhance the frequency quality of the power system and improve the efficiency of the market.