Rodney Yeu with adviser Peter W. Sauer Dynamic security assessment is an analysis of a power system made to determine if the system can withstand contingencies or certain probable disturbances and still operate in a satisfactory manner. A part of this assessment is the small-signal stability assessment of a power system that is traditionally done […]
Geometric and Game Theoretic Control of Energy Assets in Small Scale Power Systems
Wayne Weaver with adviser Philip T. Krein Power electronics are prevalent at all levels of power systems, including many loads and in renewable energy resources, such as photovoltaics and wind generation. This is both a curse and a blessing to the power system design engineer—a curse because power electronic loads can regulate energy intake so […]
Identification of Critical Cutsets for Static Collapse Analysis
Brian C. Raczkowski with adviser Peter W. Sauer This topic deals with static transfer stability limits (STSL) and transfer loss stability limits (TLSL) of network branches, cutsets of network branches, and their relation to power flow Jacobian singularity. A minimal cutset is a grouping of system branches that—if removed from the system—separates the seller and […]
Reduction of Dynamic Nonlinear Models of Magnetic Devices
Liyan Qu with adviser Patrick L. Chapman FEM is a powerful numerical technique widely used in the analysis of electric machinery and power electronics. Given geometrical data and material information, physics-based, FEA models can be generated automatically. Unlike behavioral modals, they sometimes rely on many unrealistic assumptions (such as sinusoidal windings, perfectly balanced windings, and […]
Transient Reduction of dc-dc-Converters via Augmentation and Geometric Control
Grant Pitel with adviser Philip T. Krein Fast dc-dc dynamic performance is crucial for supplying clean power to dynamic loads. This is a particular concern in low-voltage digital systems in which fast, high-current load steps can lead to significant transients. Two approaches are being evaluated that allow converters to reject disturbances without sacrificing bandwidth—counteracting goals. […]
Biomechanical Energy Conversion
Penglin Niu with adviser Patrick L. Chapman Based on previous work on biomechanical energy conversion, we have identified two motions—horizontal foot movement and up-down center-of-gravity movement—as energy sources and a linear moving-coil magnetic-generator model for power conversion. Testing of the second-stage prototype devices has shown significant power output from both motions. Further work was also […]
Integrated Electric Machine and Drive for Single-Phase Applications
Brett M. Nee with adviser Patrick L. Chapman Electric machines are a part of our everyday lives, often taken for granted, and consume sixty percent of our nation’s electricity. Most electric machines are fractional-horsepower, single-phase induction motors, widely used for their reliability, mature manufacturing process, low cost, and nearly speed-independent torque. But the single-phase machine […]
The Development of Power System Load Models Using PMU Data
Shanshan Liu with adviser Peter W. Sauer Power system load representation has a significant impact on power system analysis and control results. Unlike generators, excitation systems and transformers, which are devices, loads evolve with time, making the task of developing standard load model structure rather challenging. A phasor measurement unit (PMU) provides instant system data; […]
A Microgrid Architecture with Multiple-Input dc/dc Converters: Applications, Reliability, System Operation, and Control
Alexis Kwasinski with adviser Philip T. Krein A microgrid is an independently controlled portion of an electrical grid. It comprises its own power sources, energy storage devices, and loads. A microgrid can achieve improved local reliability and high efficiency relative to the complete power grid. It also provides uninterruptible power supply functions. These characteristics make […]
DC-DC Converter Design with Integrated-Circuit Implementation and Predictive Energy Optimization Scheme
Yingying Kuai with adviser Patrick L. Chapman Integrated circuit (IC) implementation of dc-dc converters is popular in portable electronic systems, as it is the most cost-effective approach to design a complex electronic system. There is a growing application sector within the hand-held electronics market where the dc-dc converter’s load consists of a generic amplifier or […]