Model-Free Predictive Current Control for Three-Phase Power Converters With LCL Filter

This paper deals with a battery energy storage system (BESS) in only one of its multiple operating modes, that is when the BESS is charging the battery bank and with the focus on the control scheme design for the BESS input stage, which is a three-phase LCL-filter PWM rectifier. The rectifier's main requirements comprise output voltage regulation, power factor control, and low input current harmonic distortion, even in the presence of input voltage variations. Typically, these objectives are modeled by using a dq model with its corresponding two-loop controller architecture, including an outer voltage loop and a current internal loop. This paper outlines an alternative approach to tackle the problem by using not only an input–output map linearization controller, with the aim of a single-loop current control, but also by avoiding the dq modeling. In this case, the voltage is indirectly controlled by computing the current references based on the converter power balance. The mathematical model of the three-phase LCL-filter PWM rectifier is defined based on the delta connection of the filter, which accomplishes the requirements of a 100 kW BESS module. Extensive simulation results are included to confirm the performance of the proposed closed-loop control in practical applications.

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A Simple High-Performance Current Control Strategy for V2G Three-Phase Four-Leg Inverter With LCL Filter

IEEE Transactions on Transportation Electrification ◽

10.1109/tte.2019.2936684 ◽

2019 ◽

Vol 5 (3) ◽

pp. 695-701

Author(s):

Cuilan Tan ◽

Qihong Chen ◽

Keliang Zhou ◽

Liyan Zhang

Keyword(s):

Control Strategy ◽

High Performance ◽

Current Control ◽

Lcl Filter ◽

Three Phase

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A Discrete RMRAC-STSM Controller for Current Regulation of Three-Phase Grid-Tied Converters with LCL filter

10.53316/sepoc2021.033 ◽

2021 ◽

Author(s):

GUILHERME VIEIRA HOLLWEG ◽

PAULO JEFFERSON DIAS DE OLIVEIRA EVALD ◽

EVERSON MATTOS ◽

RODRIGO VARELLA TAMBARA ◽

HILTON ABíLIO GRüNDLING

Keyword(s):

Control Structure ◽

Reference Model ◽

Sliding Mode ◽

Adaptive Controller ◽

Current Control ◽

Robust Adaptive Control ◽

Lcl Filter ◽

Robust Model ◽

Three Phase ◽

Robust Adaptive

This article presents a discrete robust adaptive control structure, gathering a Robust Model Reference Adaptive Controller (RMRAC) with an adaptive Super-Twisting Sliding Mode (STSM) controller. The resulting control structure is applied to current control of a voltage-fed three-phase inverter, connected to the grid by an LCL filter. The main contribution of this control proposal is its adaptability, maintaining the robustness characteristics of the controllers that compose it with good regulation performance. Moreover, as the adaptive Sliding Mode action is high-order (Super-Twisting), the chattering phenomenon is significantly mitigated. Thereby, its implementation is simplified, using a first order reference model. For this, the dynamics of the LCL filter capacitors are neglected during the modeling process, considering it as an additive unmodeled dynamics. To validate the viability of the proposed control structure, Hardware in the Loop (HIL) results are presented.

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Low cogging torque design and simplified model-free predictive current control for radial-flux dual three-phase permanent magnet electric machines

Advances in Mechanical Engineering ◽

10.1177/1687814019891644 ◽

2019 ◽

Vol 11 (12) ◽

pp. 168781401989164

Author(s):

Hsing-Cheng Yu ◽

Hung-Wei Lai ◽

Li-Jhen Chen ◽

Cheng-Kai Lin

Keyword(s):

Permanent Magnet ◽

Control Method ◽

Torque Ripple ◽

Electric Machines ◽

Current Control ◽

Simplified Model ◽

Cogging Torque ◽

Model Free ◽

Radial Flux ◽

Three Phase

This study presents two improved designs of eccentric-shaped permanent magnets and teeth-shaped stators in radial-flux dual three-phase permanent magnet electric machines to reduce cogging torque and torque ripple. The finite element analysis (ANSYS Electromagnetics) has been adopted in simulation, and real radial-flux dual three-phase permanent magnet electric machines have been fabricated in experiment to verify the study. Using the radial-flux dual three-phase permanent magnet electric machines in electric machine systems can improve the reliability and obtain higher output torque. In electrical drives and control, a simplified model-free predictive current control method has been proposed and implemented to drive the radial-flux dual three-phase permanent magnet electric machines, and the control law has been achieved by a TMS320F28377S microcontroller of Texas Instruments. The simplified model-free predictive current control method is senseless to parameter variations and back electromotive force of the permanent magnet electric machines, and only needs current sensors to detect six-phase current. The optimal one has been chosen by 14 various switching modes, which has the minimum cost function, and then the converter can be directly driven and controlled in the next sampling period. The features of the simplified model-free predictive current control method can reduce the algorithm calculation and avoid the defect of conventional model-based predictive current control scheme. A proportional-integral speed controller has also been designed to achieve the speed response of the fixed-speed tracking effect. Finally, the feasibility and effectiveness of the proposed simplified model-free predictive current control method for the dual three-phase permanent magnet electric machines can be verified in the experimental and quantitative results.

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