Jonathan W. Kimball

Learn More
—This work investigates the application of an ac-ac dual active bridge converter for solid state transformer. The proposed converter topology consists of two active H-bridges and one high frequency transformer. Four-quadrant switch cells are used to ensure bi-directional power flow. The advantages of direct ac-ac conversion include fewer power conversion(More)
Cyber-Physical Systems (CPS) consist of computational components interconnected by computer networks that monitor and control switched physical entities interconnected by physical infrastructures. Ensuring stability and correctness (both logical and temporal) of a Cyber-Physical System (CPS) as a whole is a major challenge in CPS design. Any incorrectness(More)
— Interleaving PWM waveforms is a proven method to reduce ripple in dc-dc converters. The present work explores interleaving for three-phase motor drives. Fourier analysis shows that interleaving the carriers in conventional uniform PWM significantly reduces the common-mode voltage. New DSP hardware supports interleaving directly with changes to just two(More)
—Solid state transformers (SSTs) have lower physical profiles than traditional 60 Hz transformers and provide active control of power flow. However, they are not as efficient as traditional 60 Hz transformers because of the presence of power electronic converters. This work presents an analytical loss calculation model of an SST. It evaluates conduction(More)
We compared active student response (ASR) error correction and no-response (NR) error correction while teaching science terms to 5 elementary students. When a student erred on ASR terms, the teacher modeled the definition and the student repeated it. When a student erred on NR terms, the teacher modeled the definition while the student looked at the(More)
Cyber-Physical Systems (CPS) consist of distributed computation interconnected by computer networks that monitor and control switched physical entities interconnected by physical infrastructures. Finding a common semantic among these diverse components that facilitates system synthesis, verification, and monitoring is a significant challenge of a CPS(More)
Photovoltaic power plants pose some challenges when integrated with the power grid. The PV plants always focus on extracting the maximum power from the arrays. This makes the PV system unavailable for helping in regulating the grid frequency as compared to conventional synchronous generators. A new technique for tracking a pseudo-maximum power point for(More)
—In a typical microgrid, the power generation capacity is similar to the maximum total load. The low inertia of the system provides little margin for error in the power balance, both active and reactive, and requires rapid control response to load changes. In the present work, a microgrid is modeled as a Markov jump linear system (MJLS). An MJLS is a(More)