Kim, Y.; Tran, T.V.; Kim, K.-H. Robust EMPC-Based Frequency-Adaptive Grid Voltage Sensorless Control for an LCL-Filtered Grid-Connected Inverter. Electronics2024, 13, 998.
Kim, Y.; Tran, T.V.; Kim, K.-H. Robust EMPC-Based Frequency-Adaptive Grid Voltage Sensorless Control for an LCL-Filtered Grid-Connected Inverter. Electronics 2024, 13, 998.
Kim, Y.; Tran, T.V.; Kim, K.-H. Robust EMPC-Based Frequency-Adaptive Grid Voltage Sensorless Control for an LCL-Filtered Grid-Connected Inverter. Electronics2024, 13, 998.
Kim, Y.; Tran, T.V.; Kim, K.-H. Robust EMPC-Based Frequency-Adaptive Grid Voltage Sensorless Control for an LCL-Filtered Grid-Connected Inverter. Electronics 2024, 13, 998.
Abstract
A robust explicit model predictive control (EMPC)-based frequency adaptive grid voltage sensorless control is developed for a grid-connected inverter (GCI) via a linear matrix inequality (LMI) approach under the model parameter uncertainties and non-ideal grid environment. The control scheme is achieved by an enhanced prediction model rather than the conventional prediction model provided by fixed parameters to maintain the quality of grid currents injected into the grid when the model parameters are varied. Furthermore, an LMI-based observer is integrated with the disturbance observer to improve the reference tracking performance and reject disturbances. The proposed observer is employed for the grid frequency adaptive control without need of grid voltage sensors. The proposed current controller and observer employ the LMI scheme to maintain a stable and robust operation of the GCI. The discrete-time frequency response and pole-zero map analyses are used to investigate system stability and robustness against parameter uncertainties. Comprehensive simulation, experimental results and analyses clearly demonstrate the robustness of the proposed control scheme under various adverse test conditions with unexpected grid and system uncertainties.
Keywords
Disturbance observer; explicit model predictive control (EMPC); grid-connected inverters (GCIs); linear matrix inequality (LMI); uncertainties; voltage sensorless control
Subject
Engineering, Electrical and Electronic Engineering
Copyright:
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