학술논문

Predictive Control of Common-Ground Five-Level PV Inverter Without Weighting Factors and Reduced Computational Burden
Document Type
Periodical
Source
IEEE Journal of Emerging and Selected Topics in Power Electronics IEEE J. Emerg. Sel. Topics Power Electron. Emerging and Selected Topics in Power Electronics, IEEE Journal of. 11(5):4772-4783 Oct, 2023
Subject
Power, Energy and Industry Applications
Components, Circuits, Devices and Systems
Inverters
Capacitors
Voltage control
Switches
Topology
Control systems
Transformers
Common-ground (CG) inverter
control systems
model predictive controllers
multilevel inverters
photovoltaic (PV) inverter systems
Language
ISSN
2168-6777
2168-6785
Abstract
Mitigation of the leakage current components represents a critical issue in transformerless photovoltaic (PV) inverters. Recently, PV inverters with inherent common-ground (CG) connection are becoming promising proposals for nearly total elimination of leakage current components. However, developing multilevel output while injecting grid currents with high quality is a challenging task for classical control schemes. This article presents a reduced computational burden weighting factorless finite-control-set model-predictive control (WFL-FCSMPC) for the CG five-level single-phase switched capacitor cells inverter-based PV systems. The proposed reduced computational burden WFL-FCSMPC avoids the cascaded control loops of classical controllers. Thence, the problems related to adjusting weighting factors of standard finite control-set model-predictive control (FCSMPC) are eliminated by dividing the control objectives into the desired cost functions. Moreover, high computational burdens in classical FCSMPC methods are considerably reduced using the proposed WFL-FCSMPC, especially at a high number of levels. Therefore, robust and simplified design and implementation are obtained by applying the proposed WFL-FCSMPC while long tuning procedures of weighting factors are avoided. Simulation and experimental results are provided for verifying the superior performance of the proposed WFL-FCSMPC over standard FCSMPC and linear controllers.