Finite Control Set Model Predictive Control Strategies for a Three-Phase Seven-level Cascade H-Bridge DSTATCOM

Finite control set model predictive control (FCS-MPC) methods in different power electronic applications are gaining considerable attention due to their simplicity and fast dynamics. This paper introduces an assessment of the two-level three-phase voltage source converter (2L-VSC) utilizing different MPC schemes with and without a modulation stage. In order to perform such a comparative evaluation, 2L-VSC efficiency and total harmonics distortion of the voltage (THDv) have been investigated, when considering a linear load. The results demonstrate the performance of different MPC algorithms through an experimental verification on a Danfoss converter, and a set of analyses have been studied using the PLECS and MATLAB/SIMULINK together. It can be concluded that a comparable performance is achieved by using conventional MPC (CMPC), improved MPC (IMPC), periodic MPC (PMPC), and MPC scheme with modulator (M 2 PC) controllers. The assessment is critical to classify the strategies as mentioned earlier according to their efficiency. Furthermore, it gives a thorough point of view on which algorithm is suitable for the grid-forming applications.

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Finite Control Set Model Predictive Control for an LCL-Filtered Grid-Tied Inverter with Full Status Estimations under Unbalanced Grid Voltage

Energies ◽

10.3390/en12142691 ◽

2019 ◽

Vol 12 (14) ◽

pp. 2691 ◽

Cited By ~ 3

Author(s):

Xiaotao Chen ◽

Weimin Wu ◽

Ning Gao ◽

Jiahao Liu ◽

Henry Shu-Hung Chung ◽

...

Keyword(s):

Model Predictive Control ◽

Predictive Control ◽

Reactive Power ◽

Grid Voltage ◽

Luenberger Observer ◽

Reference Generator ◽

Three Phase ◽

Finite Control ◽

Control Set ◽

Unbalanced Grid

This paper proposes a novel finite control set model predictive control (FCS-MPC) strategy with merely grid-injected current sensors for an inductance-capacitance-inductance (LCL)-filtered grid-tied inverter, which can obtain a sinusoidal grid-injected current whether three-phase grid voltages are balanced or not. Compared with the conventional FCS-MPC method, four compositions are added in the proposed FCS-MPC algorithm, where the grid voltage observer (GVO) and Luenberger observer are combined together to achieve full status estimations (including grid voltage, capacitor voltage, inverter-side current, and grid-injected current), while the sequence extractor and the reference generator are applied to eliminate the double frequency ripples of the active or reactive power, or the negative sequence component (NSC) of the grid-injected current caused by the unbalanced grid voltage. Simulation model and experimental platform are established to verify the effectiveness of the proposed FCS-MPC strategy, with full status estimations under both balanced and unbalanced grid voltage conditions.

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A Comparison of Finite Control Set and Continuous Control Set Model Predictive Control Schemes for Model Parameter Mismatch in Three-Phase APF

Frontiers in Energy Research ◽

10.3389/fenrg.2021.727364 ◽

2021 ◽

Vol 9 ◽

Author(s):

Jianfeng Yang ◽

Yang Liu ◽

Rui Yan

Keyword(s):

Model Predictive Control ◽

Predictive Control ◽

Parameter Uncertainty ◽

Prediction Error ◽

Continuous Control ◽

Power Electronic ◽

Parameter Mismatch ◽

Three Phase ◽

Finite Control ◽

Control Set

Model predictive control (MPC) methods are widely used in the power electronic control field, including finite control set model predictive control (FCS-MPC) and continuous control set model predictive control (CCS-MPC). The degree of parameter uncertainty influence on the two methods is the key to evaluate the feasibility of the two methods in power electronic application. This paper proposes a research method to analyze FCS-MPC and CCS-MPC’s influence on the current prediction error of three-phase active power filter (APF) under parameter uncertainty. It compares the performance of the two model predictive control methods under parameters uncertainty. In each sampling period of the prediction algorithm, different prediction error conditions will be produced when FCS-MPC cycles the candidate vectors. Different pulse width modulation (PWM) results will be produced when CCS-MPC solves the quadratic programming (QP) problem. This paper presents the simulation results and discusses the influence of inaccurate modeling of load resistance and inductance parameters on the control performance of the two MPC algorithms, the influence of reference value and state value on prediction error is also compared. The prediction error caused by resistance mismatch is lower than that caused by inductance mismatch, more errors are caused by underestimating inductance values than by overestimating inductance values. The CCS-MPC has a better control effect and dynamic performance in parameter mismatch, and the influence of parameter mismatch is relatively tiny.

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Finite Control Set Model Predictive Control of Six-Phase Asymmetrical Machines—An Overview

Energies ◽

10.3390/en12244693 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4693 ◽

Cited By ~ 9

Author(s):

Pedro Gonçalves ◽

Sérgio Cruz ◽

André Mendes

Keyword(s):

Model Predictive Control ◽

Predictive Control ◽

High Performance ◽

Control Strategies ◽

Current Control ◽

Torque Control ◽

Current Harmonics ◽

Electric Drives ◽

Finite Control ◽

Control Set

Recently, the control of multiphase electric drives has been a hot research topic due to the advantages of multiphase machines, namely the reduced phase ratings, improved fault tolerance and lesser torque harmonics. Finite control set model predictive control (FCS-MPC) is one of the most promising high performance control strategies due to its good dynamic behaviour and flexibility in the definition of control objectives. Although several FCS-MPC strategies have already been proposed for multiphase drives, a comparative study that assembles all these strategies in a single reference is still missing. Hence, this paper aims to provide an overview and a critical comparison of all available FCS-MPC techniques for electric drives based on six-phase machines, focusing mainly on predictive current control (PCC) and predictive torque control (PTC) strategies. The performance of an asymmetrical six-phase permanent magnet synchronous machine is compared side-by-side for a total of thirteen PCC and five PTC strategies, with the aid of simulation and experimental results. Finally, in order to determine the best and the worst performing control strategies, each strategy is evaluated according to distinct features, such as ease of implementation, minimization of current harmonics, tuning requirements, computational burden, among others.

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Finite Control Set Model Predictive Control for Paralleled Uninterruptible Power Supplies

Energies ◽

10.3390/en13133453 ◽

2020 ◽

Vol 13 (13) ◽

pp. 3453

Author(s):

Tiago Oliveira ◽

Luís Caseiro ◽

André Mendes ◽

Sérgio Cruz

Keyword(s):

Model Predictive Control ◽

Predictive Control ◽

Control Strategies ◽

Power Supplies ◽

Voltage Waveform ◽

High Quality ◽

Uninterruptible Power Supplies ◽

Finite Control ◽

Control Set ◽

Uninterruptible Power

Nowadays, uninterruptible power supplies (UPS) play an important role in feeding critical loads in the electric power systems such as data centers or large communication hubs. Due to the increasing power of these loads and frequent need for expansion or redundancy, UPS systems are frequently connected in parallel. However, when UPS systems are parallel-connected, two fundamental requirements must be verified: potential circulating currents between the systems must be eliminated and the load power must be distributed between the systems according to UPS systems availability. Moreover, a high-quality load voltage waveform must be permanently ensured. In this paper innovative control strategies are proposed for paralleled UPS systems based on Finite Control Set Model Predictive Control (FCS-MPC). The proposed strategies simultaneously provide: controlled load power distribution, circulating current suppression and a high-quality load voltage waveform. A new dynamic converters deactivation mechanism is proposed. This new technique provides improved overall system efficiency and reduced power switches stress. In this paper, two multilevel based UPS systems are parallel-connected. Each UPS contains two three-level Neutral Point-Clamped-Converters (3LNPC) and a three-level DC-DC converter. The presented experimental results demonstrate the effectiveness of the proposed control strategies in several operating conditions.

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