Impacts of Load on Miller-Effect Transients

In this work, experimental results reveal that under no-load conditions, the switching behavior is controlled by the gate driver, where the Miller plateau appears. But at higher load currents, switching is dominated by the current-commutation mechanism. 

Synchronization of Inverters in Grid-Forming Mode

In this work, we have developed two synchronization methods to address an inverter’s seamless connection or reconnection to an islanded microgrid in grid-forming mode, namely the controller-sync method and the output-sync method. 

Self-Protective Inverters Against Malicious Setpoints Using Analytical Reference Models

In this work, Communication protocols and system-level protection may fail if the data is sent from authorized sources. We have developed device-level self-protection for grid-interactive smart inverters. 

Weak Grid Impacts on the Stability of Grid-Tied Inverters

In this work, we have 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. 

Dynamic Performance of Variable-Frequency AC-DC Converters

In this work, we have developed a parameter estimation and control scheme for a variable-frequency AC–DC converter, experimentally validating its ability to regulate DC-bus voltage and maintain unity power factor under rapid input-frequency changes and filter parameter variations.

Ultra-fast Rectifier for Variable Frequency Applications

In this work, we have developed and experimentally tested an adaptive parameter estimation algorithm for a variable-frequency active rectifier. Integrated into the control scheme, the estimator compensates for hardware–controller parameter mismatches, enabling tight DC-bus voltage regulation and unity power factor under varying operating conditions.

High Frequency Models for Magnetic Circuits and Motors

A three-phase universal motor model depicting the motor behavior from low to high frequencies is developed. The universal model is derived by extending the low-frequency standard T-equivalent circuit (IEEE Standard 112), and thus high-frequency effects caused by common-mode and differential-mode can be included in the motor model.