Energies

2024

Jump to: 2023, 2022

21 pages, 10718 KiB

Open AccessArticle

Adaptive Fast Integral Terminal Sliding Mode Control Strategy Based on Four-Switch Buck–Boost Converters

by Borui Ma, Jiye Jiao and Zilong Ye

Energies 2024, 17(15), 3645; https://doi.org/10.3390/en17153645 - 24 Jul 2024

Viewed by 664

Abstract

With the rapid development of electronic power systems, DC-DC converters are widely used, including the Four-Switch Buck–Boost (FSBB) converter, which has a unique advantage in scenarios with a wide range of voltage inputs. To improve the response speed and anti-interference capability of the [...] Read more.

With the rapid development of electronic power systems, DC-DC converters are widely used, including the Four-Switch Buck–Boost (FSBB) converter, which has a unique advantage in scenarios with a wide range of voltage inputs. To improve the response speed and anti-interference capability of the FSBB converter, this paper proposes an adaptive global fast integral terminal sliding mode control method. Through an in-depth analysis of the fundamental characteristics of the FSBB converter, this study employed a global fast integral terminal sliding mode controller combined with an adaptive algorithm to significantly improve the dynamic performance and robustness of the FSBB converter. The simulation and experimental results show that the proposed method could track the reference voltage quickly and accurately in different modes, exhibiting excellent system robustness compared to conventional sliding mode control, terminal sliding mode control, and PID control methods. Full article

► Show Figures

Figure 1

19 pages, 4060 KiB

Open AccessArticle

SMC Algorithms in T-Type Bidirectional Power Grid Converter

by Albert Sawiński, Piotr Chudzik and Karol Tatar

Energies 2024, 17(12), 2970; https://doi.org/10.3390/en17122970 - 17 Jun 2024

Viewed by 649

Abstract

In this paper, the implementation of sliding mode control algorithms for the case of power grid current regulation in a T-type bidirectional inverter system connected via an LCL filter to the power grid is proposed and presented. A mathematical model of such a [...] Read more.

In this paper, the implementation of sliding mode control algorithms for the case of power grid current regulation in a T-type bidirectional inverter system connected via an LCL filter to the power grid is proposed and presented. A mathematical model of such a system has been proposed, which was then implemented in a simulation environment. The method of designing sliding controllers using the Lyapunov method to conduct a stability proof is presented. The article includes a comparative analysis of two sliding mode control algorithms: the classic one, which includes equivalent control, discontinuous part, and proportional reaching law, and the hybrid one, in which the discontinuous part and reaching law were modified. Full article

► Show Figures

Figure 1

21 pages, 7683 KiB

Open AccessArticle

Non-Weighted Two-Stage Model Predictive Control Strategy Based on Three-Level NPC Inverter

by Guifeng Wang, Peiru Li and Yu Wang

Energies 2024, 17(8), 1813; https://doi.org/10.3390/en17081813 - 10 Apr 2024

Cited by 2 | Viewed by 877

Abstract

This paper investigates the asynchronous motors driven by a Three-Level Neutral-Point-Clamped Voltage Source Inverter (3L-NPC-VSI) and aims to achieve control without weight factors and reduce torque ripple. It puts forward a non-weighted two-stage Finite-Control-Set Model Predictive Control (FCS-MPC) strategy. First, a hierarchical optimization [...] Read more.

This paper investigates the asynchronous motors driven by a Three-Level Neutral-Point-Clamped Voltage Source Inverter (3L-NPC-VSI) and aims to achieve control without weight factors and reduce torque ripple. It puts forward a non-weighted two-stage Finite-Control-Set Model Predictive Control (FCS-MPC) strategy. First, a hierarchical optimization method is adopted to address the difficulty of setting weight factors in traditional FCS-MPC applications. The method offers stratified designs of three performance indices, voltage jump, common-mode voltage, and current tracking, obviating the need for weight factor setting and reducing the calculation load of predictions. Secondly, to further mitigate torque ripple, an optimal vector or vector combination is implemented at the current control layer by adhering to the principle of minimal current tracking error. During the selection of the optimal vector combination, the first vector of the combination is chosen to be the vector at the end of the present cycle. This ensures that there is at most one switch within each control period, reducing the switching losses of the two-stage FCS-MPC. Lastly, detailed simulation and experimental analyses are conducted to verify the feasibility and effectiveness of the proposed strategy. Full article

► Show Figures

Figure 1

18 pages, 5962 KiB

Open AccessArticle

Phase-Shifting Adaptive LLC Resonant Converter with Reduced Turn-Off Loss in Wide Voltage Application

by Hongxun Jiang and Xiumei Yue

Energies 2024, 17(7), 1555; https://doi.org/10.3390/en17071555 - 25 Mar 2024

Viewed by 1675

Abstract

In this paper, a hybrid control method with adaptive phase-shifting modulation (PSM) and pulse-frequency modulation (PFM) is proposed to optimize the steady-state performance of an LLC resonant converter in wide voltage-gain range application. For the primary-side switches under the hybrid control method, zero-voltage [...] Read more.

In this paper, a hybrid control method with adaptive phase-shifting modulation (PSM) and pulse-frequency modulation (PFM) is proposed to optimize the steady-state performance of an LLC resonant converter in wide voltage-gain range application. For the primary-side switches under the hybrid control method, zero-voltage switching (ZVS) performance is maintained over wide voltage-gain range and the turn-off loss is reduced; therefore, the converter reconciles wide voltage-gain range and high efficiency. Mode characteristics under different phase-shifting-angle-θ and switching-frequency-fs combinations is analyzed, and then the soft-switching characteristic is revealed. By introducing time domain analysis, the turn-on current of the primary-side switches is calculated, and thus the ZVS boundary of different θ and fs combinations is inferred. In addition, to acquire the optimum steady-state operation of the converter, the turn-off current is calculated; by making the converter work near to the minimum turn-off current operating point, the turn-off loss can be reduced greatly. With the principles of achieving ZVS performance and minimizing turn-off current, the phase-shifting angle θ of PSM is designed to be adaptive to the reference output voltage, no additional circuits are needed, and the two control degrees (θ and f_s) are simplified to one (f_s). The simulation and experiment are developed to verify the feasibility and effectiveness of the hybrid control method; the results show that ZVS performance is maintained at wide voltage-gain range and the turn-off current of the hybrid control method is reduced to that of the single PFM, and thus the turn-off loss is reduced. The efficiency comparison validates the fact that the hybrid control method has less power loss than single PSM and single PFM. Full article

► Show Figures

Figure 1

30 pages, 6458 KiB

Open AccessArticle

Modular Circuit Synthesis Oriented Modelling Approach for Non-Isolated DC-DC Converters in DCM

by Lebogang Masike and Michael Njoroge Gitau

Energies 2024, 17(5), 1263; https://doi.org/10.3390/en17051263 - 6 Mar 2024

Viewed by 853

Abstract

The continued and envisioned large-scale integration of renewable energy sources as a reaction to rising global temperatures and climate change will need a readily available DC grid to increase commissioning and operating efficiency. The effective operation of these grids is predicated on the [...] Read more.

The continued and envisioned large-scale integration of renewable energy sources as a reaction to rising global temperatures and climate change will need a readily available DC grid to increase commissioning and operating efficiency. The effective operation of these grids is predicated on the correct control of its main control points. A plethora of DC-DC converters that find use in DC microgrids act as the main control points. DC-DC converters are non-linear and can operate in different modes with completely unique characteristics. To utilise classical control techniques, laborious equivalent linear models are derived for DC-DC converters using averaging modelling schemes. The application and limitations of these modelling techniques are well captured in the available literature. The most common limitation of the available modelling schemes is that more focus is dedicated to converter attributes like order, functionality and operating mode, even when optimal power flow and voltage regulation within the DC network are of more interest. Structure-based modelling techniques like the use of basic building blocks nullify converter attributes in the modelling process which translates to modelling efficiency. In light of the merits seen with the use of basic building blocks when modelling converters in CCM, the current study extends these merits to converters operation in DCM. Similar to modelling converters in CCM, modelling techniques that are available in the literature continue to consider converter attributes in the modelling process for DCM operation. Moreover, the two modes of operation are treated as unique entities and often modelled in a non-unified manner, which compromise modelling efficiency since the same converter can operate in a different state solely based on loading. The aim is to increase modelling efficiency but also nullify operating mode in the modelling process. The same basic building blocks are now modelled as two-port networks for DCM operation and adopted based on the exact configuration of a specified converter to compute its steady-state and dynamic models. All the advantages seen when modelling converters in CCM using basic building blocks are retained and augmented when considering DCM operation. Thus, any converter with well-defined basic building blocks can be easily modelled solely based on the connection of constituent basic building blocks. Full article

► Show Figures

Figure 1

14 pages, 3807 KiB

Open AccessArticle

An Open-Circuit Fault Diagnosis Method for LLC Converters

by Shibo Xiong, Yuxuan Pei, Weikang Wang, Wenwei Liu, Peng Zhang and Yang Liu

Energies 2024, 17(4), 817; https://doi.org/10.3390/en17040817 - 8 Feb 2024

Viewed by 1015

Abstract

In electrified transportation systems, power system failures can lead to greater disasters. Therefore, the reliability of converters in transportation systems has been a concern. Fault-tolerant techniques are widely applied to ensure that converters can continue to supply loads under fault conditions. Fault diagnosis [...] Read more.

In electrified transportation systems, power system failures can lead to greater disasters. Therefore, the reliability of converters in transportation systems has been a concern. Fault-tolerant techniques are widely applied to ensure that converters can continue to supply loads under fault conditions. Fault diagnosis as a prerequisite for fault tolerance has also become a research hotspot. This paper proposes a fast method for fault diagnosis of high-frequency LLC converters. The proposed fault diagnosis method is based on the observation of the voltage across the resonant capacitor to determine and locate the faulty power switch, providing a basis for fault tolerance. This diagnosis method requires a voltage sensor, which is also necessary for some control methods. When applying these control methods, the proposed fault diagnosis method can be used without additional sensors, beneficial for cost reduction. A full-bridge LLC converter controlled by a digital signal processor was used as an experimental platform to verify the effectiveness and speed of the proposed diagnostic method. The results show that the proposed fault diagnosis method can achieve the fast diagnosis of high-frequency LLC converters in a short time and with only minimal computational resources. Full article

► Show Figures

Figure 1

2023

Jump to: 2024, 2022

22 pages, 19066 KiB

Open AccessArticle

An Analysis and Optimization of the Battery Capacity Difference Tolerance of the Modular Multi-Level Half-Bridge Energy Storage Converter

by Yuhang Pan, Qingsong Wang and Giuseppe Buja

Energies 2023, 16(23), 7789; https://doi.org/10.3390/en16237789 - 27 Nov 2023

Viewed by 873

Abstract

As a power converter of battery energy storage, the multi-level converter and its battery balancing control have received much attention from scholars. This paper focuses on the modular multi-level half-bridge energy storage converter (MMH-ESC), including its topology, working principle, and pulse width modulation [...] Read more.

As a power converter of battery energy storage, the multi-level converter and its battery balancing control have received much attention from scholars. This paper focuses on the modular multi-level half-bridge energy storage converter (MMH-ESC), including its topology, working principle, and pulse width modulation (PWM) methods. Under the battery balancing control strategy based on level-shifted carrier PWM (LS-PWM), formulas are derived and calculations are performed to get the charge or discharge of each submodule (SM), thereby obtaining the tolerance for capacity differences among these batteries. A range of battery capacity values that can maintain a balanced state is provided to enhance flexibility in battery configuration and utilization, avoiding the limitation of all batteries to the same capacity. Finally, a new bridge arm modulation wave allocation method is proposed. This method significantly expands the range of SM battery capacity selection and provides a high-tolerance modulation method for the converter under extreme or even fault conditions. Full article

► Show Figures

Figure 1

17 pages, 4299 KiB

Open AccessArticle

An Active Power Dynamic Oscillation Damping Method for the Grid-Forming Virtual Synchronous Generator Based on Energy Reshaping Mechanism

by Rongliang Shi, Caihua Lan, Zheng Dong and Guihua Yang

Energies 2023, 16(23), 7723; https://doi.org/10.3390/en16237723 - 23 Nov 2023

Cited by 4 | Viewed by 1245

Abstract

The grid-forming virtual synchronous generator (GFVSG) with large virtual inertia can provide a friendly grid-connected operational mode for power electronic converters, but it may also introduce the active power dynamic oscillation problems similar to traditional synchronous generators. In view of this, the dynamic [...] Read more.

The grid-forming virtual synchronous generator (GFVSG) with large virtual inertia can provide a friendly grid-connected operational mode for power electronic converters, but it may also introduce the active power dynamic oscillation problems similar to traditional synchronous generators. In view of this, the dynamic equivalent circuit model of the GFVSG grid-tied active power-angle is established firstly, and, then, the understanding of the GFVSG active power oscillations under variable disturbances is revealed from the perspective of circuit energy flow in this paper. On this basis, an active power dynamic oscillation damping method based on an energy reshaping mechanism for the GFVSG is proposed, and a parameter design method using the second-order equivalent reduced-order control model is given. The MATLAB 2016a simulation as well as experimental test platforms of a 100 kV·A GFVSG grid-connected system are established, then, both the feasibility and effectiveness of the proposed active power dynamic oscillation damping method are verified by using the simulation and experimental comparison results. Full article

► Show Figures

Figure 1

18 pages, 20969 KiB

Open AccessArticle

Optimal Asymmetric Duty Modulation for Dual Active Bridge Converters with DC Blocking Capacitors

by Peng Dai, Shuyu Liu, Shiqi Fang and Zheng Gong

Energies 2023, 16(18), 6674; https://doi.org/10.3390/en16186674 - 18 Sep 2023

Cited by 1 | Viewed by 1188

Abstract

Aiming at the optimization of current stress with low voltage ratio and full ZVS, a control method combining variable duty cycle and phase shift was proposed based on dual active bridge (DAB) converters with DC blocking capacitors. By adding DC bias to the [...] Read more.

Aiming at the optimization of current stress with low voltage ratio and full ZVS, a control method combining variable duty cycle and phase shift was proposed based on dual active bridge (DAB) converters with DC blocking capacitors. By adding DC bias to the DC blocking capacitors, asymmetric duty modulation (ADM) can adjust the bias as needed. Based on the theoretical analysis of steady-state operation, the operating modes can be divided into eight modes. According to the features of each mode, equivalent circuits are established. The transmission power and the boundary of zero-voltage-switching (ZVS) are deduced through a detailed analysis of each mode. Based on the theoretical deduction, ADM is more suitable for a low voltage ratio. Verified by experiment, optimized asymmetric duty modulation (OADM) can increase efficiency by 3.58%, 6.57%, 8.81%, and 10.33% compared with DPS when P is equal to 0.36 and m is equal to 0.4, 0.3, 0.2, and 0.1, respectively. Using this method, the current stress of the converter is lighter than that under regular modulation when the voltage ratio m ≤ 0.5 with full ZVS. Full article

► Show Figures

Figure 1

20 pages, 10740 KiB

Open AccessArticle

Resonance Characteristics of the LLC Resonant Half-Bridge Converter for the Rapid Charging of Personal Mobility Device Smart Batteries

by Jin-Yong Bae

Energies 2023, 16(18), 6538; https://doi.org/10.3390/en16186538 - 11 Sep 2023

Cited by 1 | Viewed by 1511

Abstract

This study discusses the resonance characteristics of the LLC resonant half-bridge converter and smart battery charging for the fast charging of personal mobility devices (e.g., electric kickboards, segways, hoverboards, electric bicycles, and electric motorcycles), whose use is rapidly increasing. Through the analysis of [...] Read more.

This study discusses the resonance characteristics of the LLC resonant half-bridge converter and smart battery charging for the fast charging of personal mobility devices (e.g., electric kickboards, segways, hoverboards, electric bicycles, and electric motorcycles), whose use is rapidly increasing. Through the analysis of resonance characteristics, this study aims to validate that f_S > f₀ is the most appropriate correlation in the relationship between resonant frequency (f₀) and switching frequency (f_S) that is suitable for the rapid charging of batteries of personal mobility devices. Additionally, the proposed half-bridge converter does not charge the battery from discharge or misconnection based on the detection of the battery voltage for the batteries of personal mobility devices. Therefore, the proposed converter suggests a charging system based on battery state detection that stably performs rapid charging of the batteries of personal mobility devices by equalizing the battery voltage and the charger voltage through a pre-charge operation. Full article

► Show Figures

Figure 1

24 pages, 4152 KiB

Open AccessArticle

Optimal Sliding-Mode Control of Semi-Bridgeless Boost Converters Considering Power Factor Corrections

by José R. Ortiz-Castrillón, Sergio D. Saldarriaga-Zuluaga, Nicolás Muñoz-Galeano, Jesús M. López-Lezama, Santiago Benavides-Córdoba and Juan B. Cano-Quintero

Energies 2023, 16(17), 6282; https://doi.org/10.3390/en16176282 - 29 Aug 2023

Cited by 3 | Viewed by 1284

Abstract

Sliding-mode control (SMC) is a robust technique used in power electronics (PE) for controlling the behavior of power converters. This paper presents simulations and experimental results of an optimal SMC strategy applied to Semi-Bridgeless Boost Converters (SBBC), which includes Power Factor Correction (PFC). [...] Read more.

Sliding-mode control (SMC) is a robust technique used in power electronics (PE) for controlling the behavior of power converters. This paper presents simulations and experimental results of an optimal SMC strategy applied to Semi-Bridgeless Boost Converters (SBBC), which includes Power Factor Correction (PFC). As the main contribution, the optimal coefficients of the SMC strategy are obtained using two metaheuristic approaches, namely the Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). The main objective is to obtain the sliding coefficients that ensure the best converter response in terms of the input current and output voltage, both during start-up and under disturbances (including changes in load, source, and references). The fitness function to be minimized includes two coefficients, namely the Integrative Absolute Error (IAE) and the Integral Time Absolute Error (ITAE), for both the input current and output voltage. These coefficients measure the converter’s effort to follow the control references. The IAE penalizes errors during start-up, whereas the ITAE penalizes errors in the steady state. The tests carried out demonstrated the effectiveness of the GA and PSO techniques in the optimization process; nonetheless, the GA outperformed the PSO approach, providing sliding coefficients that allowed for a reduction in the input current overshoot during start-up of up to 24.15% and a reduction in the setting time of the output voltage of up to 99%. The experimental results were very similar when tuning with the GA and PSO techniques; nevertheless, tuning with the GA technique produced a better response in the face of disturbances compared to the PSO technique. Full article

► Show Figures

Figure 1

20 pages, 4932 KiB

Open AccessArticle

Harmonic Analysis of Sliding-Mode-Controlled Buck Converters Imposed by Unmodeled Dynamics of Hall Sensor

by Yanmin Wang, Guangxin Duan, Juan Yu, Wenjiao Yue, Jiaming Ning and Bailiang Liu

Energies 2023, 16(17), 6124; https://doi.org/10.3390/en16176124 - 22 Aug 2023

Cited by 1 | Viewed by 1104

Abstract

DC–DC buck converters have become prominent components for energy optimization in power systems, and how to improve control performances is a challenging issue to be addressed. In this paper, we aim to investigate the harmonic problem of sliding mode (SM) controlled buck converters [...] Read more.

DC–DC buck converters have become prominent components for energy optimization in power systems, and how to improve control performances is a challenging issue to be addressed. In this paper, we aim to investigate the harmonic problem of sliding mode (SM) controlled buck converters imposed by the often-ignored unmodeled dynamics of the Hall sensor. The unified mathematical model of the whole system is established by combining the SM controller, the buck converter, and the Hall sensor, where the signal loss in the transmission process of the whole closed-loop control system is considered. Based on the Lyapunov stability theorem, the SM controller is designed to guarantee system stability, as well as to deduce the stable working areas and the tuned controller parameters. Furthermore, we introduce the descriptive function (DF) approach to investigate the influence of the unmodeled dynamics of the Hall sensor on the system harmonics in the frequency domain, which can deduce the relationship between the amplitude-frequency characteristics of the output signal and the Hall sensor. Simulations and experiments validate this paper. Full article

► Show Figures

Figure 1

18 pages, 4723 KiB

Open AccessArticle

Modeling and Control of a Hybrid-Fed Triple-Active Bridge Converter

by Rebecca Tarraf, David Frey, Sylvain Leirens, Sebastien Carcouet, Xavier Maynard and Yves Lembeye

Energies 2023, 16(16), 6007; https://doi.org/10.3390/en16166007 - 16 Aug 2023

Cited by 1 | Viewed by 1297

Abstract

In general, the structures of Multi-Active Bridge (MAB) converters that can be found in the literature are usually based on voltage converters. However, in some cases, it could be interesting to have a current-fed input due to load characteristics or operation constraints. This [...] Read more.

In general, the structures of Multi-Active Bridge (MAB) converters that can be found in the literature are usually based on voltage converters. However, in some cases, it could be interesting to have a current-fed input due to load characteristics or operation constraints. This leads to a hybrid MAB structure mixing both current-fed and voltage-fed bridges. In this paper, a new hybrid-fed, fully coupled Triple-Active Bridge (TAB) converter topology with two voltage-fed ports and one current-fed port is studied, modelled and controlled. In the first place, a generalized average model (GAM) is developed for this system. After that, a reduced-order model is elaborated in order to simplify the behavioral study and control of this coupled system. A control strategy was also proposed in this paper, based on the developed mathematical model. Simulation results using Matlab/Simulink are presented to validate this study. Full article

► Show Figures

Figure 1

17 pages, 8438 KiB

Open AccessArticle

Predictive Control of Modular Multilevel Converters: Adaptive Hybrid Framework for Circulating Current and Capacitor Voltage Fluctuation Suppression

by Junda Li, Zhenbin Zhang, Zhen Li and Oluleke Babayomi

Energies 2023, 16(15), 5772; https://doi.org/10.3390/en16155772 - 2 Aug 2023

Cited by 3 | Viewed by 1394

Abstract

Modular multilevel converters (MMCs) are widely used in voltage-sourced, converter-based high-voltage DC systems due to their modular design, scalability, and fault tolerance capabilities. In MMCs, multi-variable control objectives can be employed by using model predictive control (MPC) due to its fast dynamic response [...] Read more.

Modular multilevel converters (MMCs) are widely used in voltage-sourced, converter-based high-voltage DC systems due to their modular design, scalability, and fault tolerance capabilities. In MMCs, multi-variable control objectives can be employed by using model predictive control (MPC) due to its fast dynamic response and ease of implementation. Nonetheless, conventional MPC techniques for MMCs have shortcomings, including high computational requirements, poor circulating current, and capacitor voltage fluctuation suppression. First, this study proposes an adaptive MPC technique that adapts the number of candidate combinations to the steady and transient states, significantly reducing the computational burden. Second, an improved hybrid combination of an MPC with a proportional-resonance (PR) controller enhances the circulating current and capacitor voltage fluctuation suppression performance. According to the phase difference between the circulating current and the capacitor voltage, the circulating current and capacitor voltage can be suppressed at different times by changing the circulating current reference of the PR controller. The switching frequency can be reduced by using the PR controller’s output to adjust the input submodule number instead of changing the duty cycle. The proposed techniques were validated by simulations and experimental case studies with a three-phase grid-connected MMC. Full article

► Show Figures

Figure 1

13 pages, 1455 KiB

Open AccessArticle

Optimized Power and Capacity Configuration Strategy of a Grid-Side Energy Storage System for Peak Regulation

by Feng Guo, Jian Li, Chi Zhang, Yizhi Zhu, Caiyang Yu, Qingsong Wang and Giuseppe Buja

Energies 2023, 16(15), 5644; https://doi.org/10.3390/en16155644 - 27 Jul 2023

Cited by 2 | Viewed by 1156

Abstract

The optimal configuration of the rated capacity, rated power and daily output power is an important prerequisite for energy storage systems to participate in peak regulation on the grid side. Economic benefits are the main reason driving investment in energy storage systems. In [...] Read more.

The optimal configuration of the rated capacity, rated power and daily output power is an important prerequisite for energy storage systems to participate in peak regulation on the grid side. Economic benefits are the main reason driving investment in energy storage systems. In this paper, the relationship between the economic indicators of an energy storage system and its configuration is first analyzed, and the optimization objective function is formulated. Then, according to the objective limitations of the energy storage system configuration and operation, the constraints are formulated. A set of typical parameters is selected, and the CPLEX (IBM ILOG CPLEX Optimization Studio) solver is used in MATLAB to solve the optimal configuration results. Several sets of optimization results are obtained by taking different subjective coefficient β values, and the economic and social benefits of the optimization results are analyzed. When the economic benefits of the energy storage system are more important, the value of β needs to be smaller, such as a value of 1000. Conversely, when the peak-regulation effect is more important, the value of β should be larger. Finally, configuration results of the control groups are given, and the effect of optimizing the calculation for improving economic benefits is verified. Full article

► Show Figures

Figure 1

19 pages, 5564 KiB

Open AccessArticle

Variable Amplitude Gate Voltage Synchronous Drive Technique for Improving Dynamic Current Balancing in Paralleled IGBTs

by Junkun Zhang, Ertao Lei, Li Jin, Kai Ma, Ying Li, Xinwei Li, Chenyang Xia and Xirui Wang

Energies 2023, 16(14), 5306; https://doi.org/10.3390/en16145306 - 11 Jul 2023

Cited by 3 | Viewed by 1106

Abstract

The problem of current sharing imbalance in the parallel connection of IGBT multi-modules affects the wide-scale application of parallel IGBT. The current imbalance problem in the dynamic process is mainly caused by the difference in control loop parameters. In parallel IGBT applications, current [...] Read more.

The problem of current sharing imbalance in the parallel connection of IGBT multi-modules affects the wide-scale application of parallel IGBT. The current imbalance problem in the dynamic process is mainly caused by the difference in control loop parameters. In parallel IGBT applications, current sharing is a critical concern. Objective differences in IGBT module and driver circuit parameters, as well as incomplete symmetry in the power circuit, lead to inconsistent parasitic parameters, resulting in both static and dynamic current-sharing issues. Static current sharing refers to the uneven distribution of load current under static operating conditions, while dynamic current sharing refers to the imbalance in current distribution among parallel IGBT modules during turn-on and turn-off processes. This is mainly influenced by the synchronization of turn-on and turn-off timings and the consistency of collector current change rates during these processes. The difference in characteristic parameters of IGBT modules is an important factor leading to the difference in control loop parameters, which has a profound impact on the dynamic current-sharing characteristics of IGBT parallel applications. In the case where the device parameters cannot be changed, some drive compensation controls can compensate for the influence of device differences on dynamic current sharing. Accurate identification of the characteristic parameters of the IGBT module is the key to this method. This paper mainly studies a synchronous variable-amplitude drive scheme and studies the influence of parameters such as synthetic gate resistance, gate-emitter capacitance, and on-off gate threshold voltage on the dynamic current-sharing characteristics. The correlation characteristics of the characteristic parameters of the IGBT device body are studied, and the characteristic model of each parameter and the influencing variable is constructed. The parallel working model of PSpice devices is established, and the influence of different characteristic parameters on the current-sharing characteristics is evaluated, and its sensitivity is summarized through simulation analysis. Through the 1700 V/300 A IGBT parallel switch characteristic experiment, the current sharing effectiveness of the synchronous variable amplitude driving method is verified. Finally, the effects of different gate control voltages and different action times on the dynamic current-sharing characteristics are summarized. Full article

► Show Figures

Figure 1

17 pages, 7267 KiB

Open AccessArticle

A Damping Control Strategy to Improve the Stability of Multi-Parallel Grid-Connected PCSs

by Xiaoyi Xu, Wenxi Yao and Gang Xie

Energies 2023, 16(12), 4633; https://doi.org/10.3390/en16124633 - 10 Jun 2023

Cited by 2 | Viewed by 1031

Abstract

In this study, to ensure stable operation of multi-parallel PCSs, a damping control strategy is adopted to restrain resonance characteristics of a parallel system, and the stability of the system is analyzed. First, the mathematical model of a single PCS is built, the [...] Read more.

In this study, to ensure stable operation of multi-parallel PCSs, a damping control strategy is adopted to restrain resonance characteristics of a parallel system, and the stability of the system is analyzed. First, the mathematical model of a single PCS is built, the capacitive current feedback-type active damping control strategy is introduced, and the effect of the damping control strategy on a single PCS under proportional-integral (PI) control is analyzed. Then, under the presence of grid impedance, a single PCS model is established and extended to multi-parallel PCSs, where a single PCS is replaced by a Norton’s equivalent circuit. The active damping method is developed, and Bode diagrams are utilized to verify that it can effectively suppress the resonance spikes of a parallel system. Finally, a simulation model of four PCSs in parallel operation is built on the Simulink platform, and the results support the correctness of the theoretical analysis. Full article

► Show Figures

Figure 1

18 pages, 6570 KiB

Open AccessArticle

Analysis and Optimization Strategy of Active Power Dynamic Response for VSG under a Weak Grid

by Rongliang Shi, Caihua Lan, Ji Huang and Chengwei Ju

Energies 2023, 16(12), 4593; https://doi.org/10.3390/en16124593 - 8 Jun 2023

Cited by 6 | Viewed by 1344

Abstract

A virtual synchronous generator (VSG) has a good adaptability to the weak grid but its grid-connected active power (GCAP) has the problem of a slow dynamic response under the active power command step. An optimization strategy of the GCAP dynamic response for the [...] Read more.

A virtual synchronous generator (VSG) has a good adaptability to the weak grid but its grid-connected active power (GCAP) has the problem of a slow dynamic response under the active power command step. An optimization strategy of the GCAP dynamic response for the VSG based on the virtual negative impedance combined with the active power transient damping control algorithm is proposed in this paper. The optimization strategy first uses the virtual negative impedance control method to reduce the VSG equivalent output impedance and the GCAP dynamic response time of the VSG. Then, the transient damping as well as the inhibition ability of the GCAP dynamic oscillation for the VSG are enhanced by the active power transient damping control algorithm. The Matlab/Simulink simulation software is used to study the GCAP dynamic response performances of the VSG in the condition of the active power command step, and the experimental test platform of a VSG grid-connected system is established. The simulation and experimental results jointly verify the feasibility and superiority of the proposed strategy in improving the GCAP dynamic response characteristics of the VSG under a weak grid. Full article

► Show Figures

Figure 1

22 pages, 4275 KiB

Open AccessArticle

Online Adaptive Parameter Estimation of a Finite Control Set Model Predictive Controlled Hybrid Active Power Filter

by Silvia Costa Ferreira, João Gabriel Luppi Foster, Robson Bauwelz Gonzatti, Rondineli Rodrigues Pereira, Guilherme Gonçalves Pinheiro and Bruno P. Braga Guimarães

Energies 2023, 16(9), 3830; https://doi.org/10.3390/en16093830 - 29 Apr 2023

Cited by 3 | Viewed by 1328

Abstract

This paper presents a novel strategy for online parameter estimation in a hybrid active power filter (HAPF). This HAPF makes use of existing capacitor banks which it combines with an active power filter (APF) in order to dynamically compensate reactive power. The equipment [...] Read more.

This paper presents a novel strategy for online parameter estimation in a hybrid active power filter (HAPF). This HAPF makes use of existing capacitor banks which it combines with an active power filter (APF) in order to dynamically compensate reactive power. The equipment is controlled with finite control set model predictive control (FCS-MPC) due to its already well-known fast dynamic response. The HAPF model is similar to a grid-connected LCL-filtered converter, so the direct control of the HAPF current can cause resonances and instabilities. To solve this, indirect control, using the capacitor voltage and the inverter-side current, is applied in the cost function, which creates high dependency between the system parameters and the equipment capability to compensate the load reactive power. This dependency is evaluated by simulations, in which the capacitor bank reactance is shown to be the most sensitive parameter, and, thus, responsible for inaccuracies in the FCS-MPC references. In order to minimize this problem without increasing the complexity of the FCS-MPC algorithm, an estimation technique, based on adaptive notch filters, is proposed. The proposed algorithm is tested in a laboratory prototype to demonstrate its ability to follow variations in the HAPF capacitor reactance, effectively correcting the reactive power reference and providing dynamic reactive power compensation. During the tests, the proposed algorithm was capable of keeping the supplied reactive power within a

1 %

error, even in a situation with

33 %

variation in the HAPF capacitor reactance. Full article

► Show Figures

Figure 1

18 pages, 3688 KiB

Open AccessArticle

Small Signal Modeling of LLC Converter with LED Load and Quasi-Resonant Controller Based Active Ripple Rejection

by Xiao Long and Dongdong Chen

Energies 2023, 16(9), 3773; https://doi.org/10.3390/en16093773 - 28 Apr 2023

Cited by 3 | Viewed by 1564

Abstract

This paper has analyzed the defects of the traditional extended description function (EDF) based LLC small signal modeling method when driving light emitting diode (LED) load and proposed an accuracy improvement method. Detailed small signal model modeling methods have been deduced, and the [...] Read more.

This paper has analyzed the defects of the traditional extended description function (EDF) based LLC small signal modeling method when driving light emitting diode (LED) load and proposed an accuracy improvement method. Detailed small signal model modeling methods have been deduced, and the accuracy of different modeling methods has been compared thoroughly. To suppress the second-order harmonic ripple in the direct current link-induced output current ripple, a quasi-resonant controller (QRC) is adopted to realize active ripple rejection (ARR). Considering the frequency of the second-order harmonic ripple changes with the grid voltage frequency, a single-phase software phase lock loop (SPLL) is adopted to extract the frequency of the second-order harmonic. By dynamically regulating the control parameter of the QRC according to the locked second-order frequency, output voltage ripple active rejection ability immune to grid voltage frequency deviation is obtained. Based on the deduced accurate small signal model, the digital controller is designed with stability, steady state and dynamics performance guaranteed. The accuracy of the proposed small signal model, the SPLL and the QRC-based ARR method has been verified at last. Full article

► Show Figures

Figure 1

21 pages, 9119 KiB

Open AccessArticle

Virtual Vector-Based Direct Power Control of a Three-Phase Coupled Inductor-Based Bipolar-Output Active Rectifier for More Electric Aircraft

by Yajun Zhao, Wenxin Huang and Feifei Bu

Energies 2023, 16(7), 3038; https://doi.org/10.3390/en16073038 - 27 Mar 2023

Cited by 3 | Viewed by 1271

Abstract

Direct power control (DPC) has gained increasing attention in recent years as a simple and efficient control strategy for pulse width modulation (PWM) rectifiers. In this paper, the idea of DPC is introduced into the three-phase coupled inductor-based bipolar-output active rectifier (TCIBAR) for [...] Read more.

Direct power control (DPC) has gained increasing attention in recent years as a simple and efficient control strategy for pulse width modulation (PWM) rectifiers. In this paper, the idea of DPC is introduced into the three-phase coupled inductor-based bipolar-output active rectifier (TCIBAR) for the first time, and a virtual vector-based direct power control (VVB-DPC) strategy is proposed for TCIBAR to realize the bipolar DC power supply for more electric aircraft (MEA). First, the mathematical model of the TCIBAR is deduced, and the basic principle of the classic DPC strategy is reviewed. On this basis, the limitations of the classic DPC strategy in TCIBAR control are analyzed. Second, a set of virtual vectors are derived to establish a novel virtual-vector switching table. Based on the virtual-vector switching table, the hysteresis power control of TCIBAR can be realized without affecting the DC-side neutral-point potential of TCIBAR. Finally, a neutral-point potential control method based on DPC architecture is studied and integrated into the VVB-DPC strategy to maintain the bipolar DC voltage balance of TCIBAR under unbalanced load conditions. The VVB-DPC strategy is experimentally studied on a TCIBAR prototype, and the experimental results verify the feasibility and effectiveness of the proposed strategy. Full article

► Show Figures

Figure 1

20 pages, 9415 KiB

Open AccessArticle

Universal Virtual Synchronous Generator Based on Extended Virtual Inertia to Enhance Power and Frequency Response

by Hao Liu, Bo Yang, Song Xu, Mingjian Du and Shuai Lu

Energies 2023, 16(7), 2983; https://doi.org/10.3390/en16072983 - 24 Mar 2023

Cited by 4 | Viewed by 2071

Abstract

Virtual synchronous generators (VSG) are considered a new generation of grid-friendly inverters with the same inertial support characteristics as synchronous generators (SG). However, the inertia support comes with the side effects of power and frequency response deterioration. The existing VSG power oscillation suppression [...] Read more.

Virtual synchronous generators (VSG) are considered a new generation of grid-friendly inverters with the same inertial support characteristics as synchronous generators (SG). However, the inertia support comes with the side effects of power and frequency response deterioration. The existing VSG power oscillation suppression methods have limitations such as complex controller parameter tuning, altering the frequency support characteristics, and power quality degradation. To address these issues, this paper proposes a universal VSG control strategy based on extended virtual inertia (VSG-EVI). Herein, the virtual inertia is no longer a constant or varying number; it is endowed with frequency domain characteristics to improve the VSG transient responses. Moreover, a detailed parameter design process is given in detail. Compared with the conventional VSG (CVSG), VSG-EVI significantly suppress the power and frequency oscillations. Compared with the existing VSG oscillation suppression methods, VSG-EVI addresses the issues of the reduction of frequency support capability, whereas the controller parametric design process is simplified with the proposed intuitive extended virtual inertia. Finally, the proposed VSG-EVI method is thoroughly validated by experiments under both grid-connected and stand-alone modes. Full article

► Show Figures

Figure 1

17 pages, 19801 KiB

Open AccessArticle

An FCS-MPC Strategy for Series APF Based on Deadbeat Direct Compensation

by Guifeng Wang, Xujie Gao and Chunjie Li

Energies 2023, 16(5), 2507; https://doi.org/10.3390/en16052507 - 6 Mar 2023

Viewed by 1543

Abstract

Aiming at the delay caused by the phase-locked loop (PLL) and harmonic detection in the traditional control of a series active power filter (SAPF), a deadbeat direct control (DBDC)-based finite control set model predictive control (FCS-MPC) strategy for the SAPF is proposed in [...] Read more.

Aiming at the delay caused by the phase-locked loop (PLL) and harmonic detection in the traditional control of a series active power filter (SAPF), a deadbeat direct control (DBDC)-based finite control set model predictive control (FCS-MPC) strategy for the SAPF is proposed in this work. Firstly, a reference voltage generation mechanism based on direct control is established, which avoids the delay in harmonic detection, thus improving the dynamic response performance of the system. Secondly, the reference current generation mechanism suitable for the SAPF is derived and established using the deadbeat control (DBC) in the αβ coordinate system, based on which the FCS-MPC system is constructed. It eliminates the complex coordinate transformation and PLL and effectively compensates for the full-frequency harmonic voltage. Finally, the proposed control strategy is verified by a simulation and an experiment. The results suggest that the proposed control strategy can effectively compensate for the load voltage and suppress harmonic distortion for the temporary swell and sag of the grid voltage, sudden load changes, and harmonic distortion conditions. Full article

► Show Figures

Figure 1

33 pages, 50382 KiB

Open AccessArticle

Zero-Phase FIR Filter Design Algorithm for Repetitive Controllers

by Pedro V. S. G. de Lima, Rafael C. Neto, Francisco A. S. Neves, Fabrício Bradaschia, Helber E. P. de Souza and Eduardo J. Barbosa

Energies 2023, 16(5), 2451; https://doi.org/10.3390/en16052451 - 4 Mar 2023

Cited by 4 | Viewed by 2413

Abstract

Repetitive controllers (RCs) are linear control structures based on the internal model principle. This control strategy is known for its ability to control periodic reference signals, even if these signals have many harmonic components. Despite being a solution that results in a good [...] Read more.

Repetitive controllers (RCs) are linear control structures based on the internal model principle. This control strategy is known for its ability to control periodic reference signals, even if these signals have many harmonic components. Despite being a solution that results in a good performance, several parameters of the repetitive controller need to be correctly tuned to guarantee its stability. Among these parameters, one that has high impact on the system performance and stability is the finite impulse response (FIR) filter, which is usually used to increase the stability domain of RC-based controllers. In this context, this paper presents a complete tutorial for designing the zero-phase FIR filter, which is often used to stabilize control systems that use RC-based controllers. In addition, this paper presents a Matlab^® application developed for performing the stability analysis of RC systems and designing its FIR filter. Simulation and experimental results of a shunt active power filter are used to validate the algorithm and the Matlab^® application. Full article

► Show Figures

Figure 1

19 pages, 6182 KiB

Open AccessArticle

Switching Frequency Limited Hysteresis Based Voltage Mode Control of Single-Phase Voltage Source Inverters

by Geethu Chacko, Lakshmi Syamala, Nithin James, Bos Mathew Jos and Mathew Kallarackal

Energies 2023, 16(2), 783; https://doi.org/10.3390/en16020783 - 10 Jan 2023

Cited by 2 | Viewed by 2243

Abstract

This paper proposes a new control strategy for single-phase voltage source inverters that does not rely on switching based on Pulse Width Modulation. The technique is similar to conventional current hysteresis control, but instead of the output current, the low-pass-filtered inverter output voltage [...] Read more.

This paper proposes a new control strategy for single-phase voltage source inverters that does not rely on switching based on Pulse Width Modulation. The technique is similar to conventional current hysteresis control, but instead of the output current, the low-pass-filtered inverter output voltage is utilised as the feedback signal. Nevertheless, the switching instants are not determined by a predefined band, but rather by a low-cost Complex Programmable Logic Device (CPLD)-based control logic, which ensures a nearly constant switching frequency. Similar to hysteresis-based control methods, the proposed method ensures a rapid dynamic response. Notable characteristics of the proposed method include a quick dynamic response, a well-defined harmonic spectrum, and an improved total harmonic distortion (THD), particularly during load current and source voltage changes. The proposed method is implemented on a 1 kW, 230 V, 50 Hz prototype. Simulation and experimental results are presented to validate the proposed concept, which demonstrates a superior dynamic response and enhanced THD during load and source voltage variations. Full article

► Show Figures

Figure 1

16 pages, 6752 KiB

Open AccessArticle

Research on a Variable-Leakage-Flux Permanent Magnet Motor Control System Based on an Adaptive Tracking Estimator

by Xiaolei Cai, Qixuan Wang, Yucheng Wang and Li Zhang

Energies 2023, 16(2), 587; https://doi.org/10.3390/en16020587 - 4 Jan 2023

Cited by 2 | Viewed by 2046

Abstract

Due to the characteristics of inductance parameter mismatch and back electromotive force harmonics caused by novel leakage flux branches and other non-ideal factors for the variable-leakage-flux permanent magnet (VLF-PM) motor, its control system suffers from a deteriorated performance of the rotor position estimation. [...] Read more.

Due to the characteristics of inductance parameter mismatch and back electromotive force harmonics caused by novel leakage flux branches and other non-ideal factors for the variable-leakage-flux permanent magnet (VLF-PM) motor, its control system suffers from a deteriorated performance of the rotor position estimation. To overcome the problems mentioned above, an adaptive tracking estimator of the rotor position is proposed in this paper for the VLF-PM motor control system. First, the proposed method simplifies the VLF-PM motor mathematical model and reduces the effect of inductance parameter variations according to the active flux concept. Then, robust and gradient descent algorithms are utilized to maintain the robustness of inductance parameter variations and eliminate the specific order harmonics owing to the novel leakage flux branches. Meanwhile, the accuracy and stability are enhanced. Furthermore, the position compensation based on the current adaptive tracking strategy is proposed to compensate the rotor position error caused by other non-ideal factors. Finally, the feasibility of the proposed estimated system is verified. Full article

► Show Figures

Figure 1

2022

Jump to: 2024, 2023

21 pages, 7111 KiB

Open AccessArticle

Sliding Mode Input Current Control of the Synchronous DC-DC Buck Converter for Electro-Mechanical Actuator Emulation in More Electric Aircrafts

by Mahdi Salimi, Christian Klumpner and Serhiy Bozhko

Energies 2022, 15(24), 9628; https://doi.org/10.3390/en15249628 - 19 Dec 2022

Cited by 2 | Viewed by 1700

Abstract

The main challenges of the input current control in synchronous DC-DC buck converters are the nonlinear model of the system, changes of the operating point in a wide range, and the need to use an input LC filter for current smoothing, which may [...] Read more.

The main challenges of the input current control in synchronous DC-DC buck converters are the nonlinear model of the system, changes of the operating point in a wide range, and the need to use an input LC filter for current smoothing, which may result in the instability of the closed-loop system. In this paper, a step-by-step approach is developed for the design and improvement of a PI-feedforward closed-loop controller. It is shown that a linear PI controller cannot stabilize the closed-loop system properly during wide changes in model parameters, e.g., an equivalent series resistance of the input filter. To cope with the stability issues, a fixed-frequency sliding mode controller (SMC) has been developed in this paper for the implementation of an electro-mechanical actuator (EMA) emulator. Moreover, a systematic approach is proposed for controller tuning and the selection of the SMC’s gains. To achieve high power efficiency, high-frequency GaN switches are used for the practical implementation of the DC-DC converter. Despite large changes in the load current, the designed nonlinear controller can track the input current reference satisfactorily. Steady-state and dynamic responses of the proposed SMC are compared with conventional linear controllers. Considering the Lyapunov stability theorem, it is proved that the designed SMC can stabilize the closed-loop system in the entire utilizable domain. The proposed nonlinear SMC controller enjoys a very simple control law. Hence, despite having very high switching and sampling frequencies, it can be easily implemented. The experimental response of the designed synchronous DC-DC buck converter is evaluated experimentally by implementing the control strategy in a TMS320F28335PGFA DSP from Texas Instrument. Moreover, the comprehensive comparison of the proposed SMC controller and a PI-feedforward controller proved the superior performance of the developed closed-loop system, in terms of the transient time response, robustness, and stability of the EMA emulator. Full article

► Show Figures

Figure 1

11 pages, 1584 KiB

Open AccessArticle

ZVS Realization of H-Bridge Low-Voltage High-Current Converter via Phase-Shift and Saturable Control

by Pingfan Xu, Xiaoyi Liu, Samson Shenglong Yu and Lisheng Pang

Energies 2022, 15(24), 9488; https://doi.org/10.3390/en15249488 - 14 Dec 2022

Viewed by 1833

Abstract

A zero-voltage switching (ZVS) H-bridge phase-shifted low-voltage high-current converter with saturable inductors is proposed in this paper. The introduction of saturable inductors solves the short circuit problem caused by high-frequency on–off of the power tube, and effectively inhibits high-frequency voltage oscillation and voltage [...] Read more.

A zero-voltage switching (ZVS) H-bridge phase-shifted low-voltage high-current converter with saturable inductors is proposed in this paper. The introduction of saturable inductors solves the short circuit problem caused by high-frequency on–off of the power tube, and effectively inhibits high-frequency voltage oscillation and voltage spikes of the rectifier tube. In addition, when the current flowing through the saturable inductor does not change rapidly, it exhibits a low impedance and consumes very little power. The detailed design process of main parameters in the converter is presented to provide design reference for power supply workers. To verify the effectiveness of design, a 3 kW(15 V/200 A) prototype converter is built. This low-voltage high-current prototype has around 90% efficiency, and can suppress high-frequency voltage oscillation and voltage spikes, avoiding the short circuit problem of power tube, all of which are verified by experimentation. Full article

► Show Figures

Figure 1

16 pages, 4209 KiB

Open AccessArticle

Model Predictive Current Control for DC-Link Ripple Voltage Suppression in Electrolytic Capacitor-Less Drive System

by Chao Zhang, Yiming Zheng, Wenchao Zhu and Rongwei Gao

Energies 2022, 15(24), 9297; https://doi.org/10.3390/en15249297 - 8 Dec 2022

Viewed by 1585

Abstract

Electrolytic capacitor-less drive systems have a higher lifespan and reliability. However, the DC-link voltage of ECL drive systems has a sudden change under dynamic conditions, which results in a serious degradation of the drive system performance. To solve the problem, this paper proposes [...] Read more.

Electrolytic capacitor-less drive systems have a higher lifespan and reliability. However, the DC-link voltage of ECL drive systems has a sudden change under dynamic conditions, which results in a serious degradation of the drive system performance. To solve the problem, this paper proposes a model predictive current control (MPCC) based on motor power change. A grid current predictive model based on motor power change is established. Motor power change is introduced into the cost function, so that grid power can quickly and accurately track the motor power under dynamic conditions, thereby effectively avoiding the sudden change of the DC-link voltage. Meanwhile, the current predictive model for decoupling inductor in the asymmetric split-capacitor active power decoupling circuit (APDC) is constructed. It realizes the high-precision complementary control of the split-capacitor voltages under various working conditions, and effectively reduces the DC-link voltage ripple. The experimental results verify the effectiveness of the proposed MPCC. Full article

► Show Figures

Figure 1

13 pages, 5292 KiB

Open AccessArticle

Cascade-Free Modulated Predictive Direct Speed Control of PMSM Drives

by Changming Zheng, Jiafeng Yang, Zheng Gong, Ziyu Xiao and Xuanxuan Dong

Energies 2022, 15(19), 7200; https://doi.org/10.3390/en15197200 - 30 Sep 2022

Cited by 4 | Viewed by 1702

Abstract

Conventional predictive control for permanent magnet synchronous motors (PMSMs) contains dual speed and current loops, and has a complex structure and multiple parameters to be tuned. Conventional predictive direct speed control (PDSC) exhibits an unsatisfactory steady-state performance. To tackle these issues, this paper [...] Read more.

Conventional predictive control for permanent magnet synchronous motors (PMSMs) contains dual speed and current loops, and has a complex structure and multiple parameters to be tuned. Conventional predictive direct speed control (PDSC) exhibits an unsatisfactory steady-state performance. To tackle these issues, this paper presents a cascade-free modulated PDSC (MPDSC) scheme for PMSM drives. First, a speed predictive model is built, where a second-order sliding mode observer is employed to quickly and robustly estimate the load torque. Then, a dual objective cost function with speed and stator current tracking is designed, which improves the system’s steady-state performance. Furthermore, the analytical solution of the constrained optimal voltage vector is derived and it is synthesized by space vector modulation, resulting in a fixed switching frequency. Experimental results show that the proposed MPDSC has stronger robustness, and lower torque ripples and stator current harmonics compared to conventional PDSC. Full article

► Show Figures

Figure 1

14 pages, 3560 KiB

Open AccessArticle

Model Predictive Phase Control for Single-Phase Electric Springs

by Qingsong Wang, Hao Ding, Shuo Yan and Giuseppe Buja

Energies 2022, 15(18), 6654; https://doi.org/10.3390/en15186654 - 12 Sep 2022

Viewed by 1464

Abstract

In this paper, model predictive control (MPC) is proposed for single-phase electric springs (ESs) with the help of the existing δ control, which is realized by controlling the instantaneous phase angle of the predefined sinusoidal reference of a certain controller. System modeling is [...] Read more.

In this paper, model predictive control (MPC) is proposed for single-phase electric springs (ESs) with the help of the existing δ control, which is realized by controlling the instantaneous phase angle of the predefined sinusoidal reference of a certain controller. System modeling is analyzed first to get differential forms of state variables. The discrete-time state space model is obtained through first-order approximation. Critical load (CL) voltage can be predicted by the prediction of ES voltage and line current. The operating modes of ESs can be determined and the reference signal for CL voltage can be provided by δ control. As a result, cost function is obtained as the absolute value of the error between predicted CL voltage and its predefined reference. Two typical operating functions such as pure reactive power compensation mode and power factor correction (PFC) mode are selected and simulated to validate the proposed control and analysis. It is revealed that both control objectives can be achieved with the proposed MPC and δ control. Additionally, the total harmonic distortion on the critical load is limited to about 0.5%, which is better than other existing methods. Full article

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

Advanced Control and Applications of Power Electronics and Power Converters

Share This Project Collection

Editors

Project Overview

Keywords

Published Papers (31 papers)

2024

Jump to: 2023, 2022

2023

Jump to: 2024, 2022

2022

Jump to: 2024, 2023

Further Information

Guidelines

MDPI Initiatives

Follow MDPI