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 two state-of-the-art laboratories 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 and may contact Dr. Mirafzal, Dr. Shadmand, or Dr. Fateh.

Directors of Power Electronics & Autonomous Systems Research Group.

PEAS Research Group Spotlight

  • 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. This award recognizes Dr. Mirafzal outstanding research accomplishments during the past five years.
  • 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 are set to receive $3.5 million award from DOE for CARE-PV project.

Research Highlights

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.

SiC based Ultrafast Rectifier for More Electric Aircraft and other Variable Frequency Applications

An ultrafast active rectifier is developed for wild-frequency applications where the rectifier is fed by a three-phase variable-frequency ac source. Three-phase ac-dc converters (rectifiers) are extensively implemented in motor-drives, wind turbines, electric vehicles and aircraft’s power systems. In some technologies, e.g. more electric aircraft and drones, power systems may employ variable-frequency generators for higher efficiency and reliability indices. The proposed ultrafast rectifier is equipped by a step-ahead predictive control scheme, an instantaneous phase-locked loop (PLL), and a module of six SiC MOSFETs.

Comprehensive Study of Weak Grid Impacts on the Stability of Grid-Tied Voltage Source Inverters

A weak grid can lead to voltage fluctuations at the inverter terminals and consequently cause inverter instability. In this project, impacts of circuit and control parameters on the stability of voltage source inverters are studied using a small-signal state-space model in the synchronously rotating dq-frame of reference. The full-order state-space model developed in this project 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 project outcomes show that a decrease in the grid inductance does not necessarily improve the stability of grid-tied VSIs.