Welcome to the Power Electronics & Autonomous Systems Research Group at Kansas State University.

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Welcome to Power Electronics & Autonomous Systems (PEAS) Research Group. We are a research group with state-of-the-art laboratory located in the Engineering Hall on the campus of Kansas State University in Manhattan, Kansas. These newly developed labs are equipped with various modern equipment and are growing.

Our goal is to perform research in the area of on-the-move energy technologies, design and control of power electronics interfaces, cybersecurity analytics of power system via smart inverters, power quality, and grid resiliency. The present website includes highlights of our research outcomes, current research staff, and ongoing research projects.

We are always looking for opportunities to establish a working relationship. Prospective students should apply to the Electrical and Computer Engineering Department graduate program.

Director of Power Electronics & Autonomous Systems Research Group.

PEAS Research Group Spotlight

  • PEAS research group will "develop grid of nanogrid (GNG) testbed" funded by National Science Foundation (NSF). The proposed testbed provides the capability to examine various hypotheses and research ideas on nanogrid controls, hardware, software, communications and security protocols, and standards, under all possible envisioned operating conditions of the power distribution grid, including faults and anomalies in both islanded and networked modes. PEAS research group are set to receive $892,000 (including cost share) award from NSF for this project. (NSF Link)
  • PEAS research group will investigate technologies to enhance distributed grid resiliency and cybersecurity with high penetration of photovoltaics. U.S. Department of Energy (DOE), Solar Energy Technologies Office (SETO) selected "CARE-PV" project proposed by Kansas State University power group to advance solar energy’s role in strengthening resiliency and cybersecurity of the electricity grid. KSU power group received $3,500,000 (including cost share) award from DOE for CARE-PV project. (DOE link)
  • PEAS research group in collaboration with Geology and Agronomy Departments will develop "Real-time measurement of sap-flow dynamics in sunflower via nuclear magnetic resonance (MRI)". This project is funded by National Science Foundation (NSF). A portable NMR tool will be designed by PEAS research group using a combination of 3D finite-element simulation package and a non-dominated sorting genetic algorithm-II to optimize the magnets' arrays and coils. The optimally-designed NMR tool will be prototyped in the lab, and its magnetic field homogeneity and intensity will be experimentally validated. The research team received $300,000 from NSF for this multidisciplinary research effort. (NSF Link)
  • PEAS Ph.D. Student Mohsen Hosseinzadehtaher received the prestigious best paper award from 2019 International IEEE Conference on Smart Grid and Renewable Energy for his paper co-authored with Ph.D. students Ahmad Khan, Matt Baker and Dr. Mohammad Shadmand. Their paper proposed novel self-healing predictive control scheme of battery energy storage system for pulse power loads in navy applications. (More Information)
  • PEAS Ph.D. Student Mitchell Easley received the prestigious best paper award from 2019 IEEE Technologies on Homeland Security Conference organized by MIT Lincoln Laboratory and Raytheon for his paper co-authored with Ph.D. student Amin Y. Fard and Dr. Mohammad Shadmand on cyber-security analytics of power distribution system using Smart Inverters. (More Information)
  • PEAS Research Group proudly announce the 1st Annual IEEE Kansas Power & Energy Conference (KPEC) at Kansas State University with technical co-sponsorship of IEEE IAS, PELS, and PES societies. This coming April, KPEC will gather experts from academia and industry to present their latest ideas and to engage in professional discourse. (KPEC Website Link) and (Call for Papers).
  • Professor Mohammad Shadmand and his Ph.D. students have been awarded 2019 Myron Zucker Student Faculty Grant from IEEE Industry Application Society (IAS) and IEEE Foundation for the project "Compact, Reliable, and Robust GaN-based Active Rectifiers for More Electric Aircraft". Dr. Shadmand and Ph.D. students Ahmad Khan, Mohsen Hosseinzadehtaher and Amin Fard will design high power density compact power converters for more electric aircraft assuring high resiliency, robustness and efficiency.
  • Professor Behrooz Mirafzal has been selected for the prestigious and competitive 2019 Frankenhoff Outstanding Research Award.

Research Highlights

GaN-based Active Rectifiers for More Electric Aircraft

PEAS research group developed a high power density compact power converters for more electric aircraft assuring high resiliency, robustness and efficiency. During the designing procedure, the effect of parasitics on steady-state operation are taken into account. Innovative design techniques are introduced to mitigate the parasitic effects in the targeted high frequency for single-phase active rectifiers. Certain design conventions in PCB layouts can lead to the asymmetrical parasitic inductances between positive and negative half switching cycles, which may further result in the asymmetrical steady state operation, higher electrical stresses, and higher thermal stresses. All these challenges are addressed during the design procedure.

Hierarchical Model Predictive Control for Cascaded Multilevel Inverter

PEAS research group developed a a hierarchical finite-set model predictive control scheme for grid-tied cascaded multilevel inverters with independent active and reactive power injection capabilities. The proposed controller has a hierarchical framework to eliminate the computationally burdensome cost function optimization and associated weight factors of the control objectives. The control formulation approach allows for multi-objective optimization with an error-tolerance framework. The control scheme achieves active and reactive power control with switching loss minimization while extracting power evenly from the independent voltage sources.

Smart Photovoltaic Inverter with Grid Fault-ride Through Capability

PEAS research group developed a single stage smart photovoltaic inverter in collaboration with Texas A&M University at Qatar. An autonomous model predictive control scheme is proposed for a single stage quasi-Z-Source grid-connected photovoltaic inverter to facilitate switching between modes of operation: maximum power point tracking (MPPT) and low voltage ride through (LVRT). The proposed smart PV inverter can respond to rapidly changing PV ambient and grid conditions and appropriately alter the current injection. The proposed controller is complemented by an observer-based MPPT algorithm with an adaptive step-size to quickly pull the PV toward and away from the MPP as necessary. The performance of the controller is verified experimentally for several grid fault and reactive power injection scenarios. The ultimate goal of this research is to develop autonomous control schemes for 1 MW medium-voltage SiC based photovoltaic cascaded multilevel inverter; this project is funded by QNRF.

Ultrafast Rectifier for Variable Frequency Applications

PEAS research group developed an adaptive control scheme for active rectifiers in wild frequency applications. The proposed controller addresses the performance degradation when the parameters of the model deviate from the actual system parameters in a variable frequency power system, e.g. More Electric Aircraft. In particular, the proposed control scheme dynamically tracks the parameters of the input filter of the converter in order to minimize the prediction error in the one-step-ahead algorithm. The results show that the proposed control scheme has a rapid dynamic response as a result of the one-step-ahead controller and the adaptation laws implemented in the model reference, which translates into fast and accurate system parameter tracking, while maintaining the dc voltage well regulated and the rectifier operating at unity power factor.

Weak Grid Impacts on the Stability of Grid-Tied Inverters

PEAS research group studied the impacts of circuit and control parameters on the stability of voltage source inverters using a small-signal state-space model in the synchronously rotating dq-frame of reference. The full-order state-space model is directly extracted from the pulsewidth modulation switching pattern and enables the stability analysis of concurrent variations in the three-phase circuit and control parameters. The system stability is a function of both the grid R/X ratio and grid inductance. Despite the grid-side inductor of the LCL filter is in series with the grid impedance, they have different impacts on the stability of a grid-tied PQ-controlled VSI, i.e., an increase in the filter inductance may improve the system stability in a weak grid. These findings are verified through simulated and experimentally obtained data.