This page has only limited features, please log in for full access.
The state of health (SOH) is a vital parameter enabling the reliability and life diagnostic of lithium-ion batteries (LIBs). A novel fusion-based SOH estimator is proposed in this study, which combines an open-circuit-voltage (OCV) model and the incremental capacity analysis (ICA). Specifically, a novel OCV model is developed to extract the OCV curve and the associated features-of-interest (FOI), from the measured terminal voltage during constant-current (CC) charge. With the determined OCV model, the disturbance-free incremental capacity (IC) curves can be derived, which enables the extraction of a set of IC morphological FOIs. The extracted model FOI and IC morphological FOIs are further fused for SOH estimation through an artificial neural network. Long-term degradation data obtained from different battery chemistries are used for validation. Results suggest that the proposed fusion-based method manifests itself with high estimation accuracy and high robustness.
Xiaolei Bian; Zhongbao Gae Wei; Weihan Li; Josep Pou; Dirk Uwe Sauer; Longcheng Liu. State-of-Health Estimation of Lithium-ion Batteries by Fusing an Open-Circuit-Voltage Model and Incremental Capacity Analysis. IEEE Transactions on Power Electronics 2021, PP, 1 -1.
AMA StyleXiaolei Bian, Zhongbao Gae Wei, Weihan Li, Josep Pou, Dirk Uwe Sauer, Longcheng Liu. State-of-Health Estimation of Lithium-ion Batteries by Fusing an Open-Circuit-Voltage Model and Incremental Capacity Analysis. IEEE Transactions on Power Electronics. 2021; PP (99):1-1.
Chicago/Turabian StyleXiaolei Bian; Zhongbao Gae Wei; Weihan Li; Josep Pou; Dirk Uwe Sauer; Longcheng Liu. 2021. "State-of-Health Estimation of Lithium-ion Batteries by Fusing an Open-Circuit-Voltage Model and Incremental Capacity Analysis." IEEE Transactions on Power Electronics PP, no. 99: 1-1.
The Vienna rectifier can produce three voltage levels, however only the neutral point is fully controllable using the bidirectional switches. The positive and negative voltage levels are decided by the current direction. As a result, the input current becomes distorted when the input current and the reference voltage have opposite signs. This can be mitigated by injecting a particular zero sequence so that the reference voltage is clamped to the neutral point during the above period. However, the converter is at risk of entering into overmodulation while operating with high modulation indices. In this paper, a hybrid modulation strategy is introduced where a calculated minimal amount of reactive current depending on the operating conditions is injected, along with the above zero sequence, to avoid overmodulation. The reduction of reactive current required compared to the state-of-the-art solutions is up to 100% in certain operating conditions. With the proposed method, the Vienna rectifier can operate in a wide range of power factors without compromising the quality of the source currents. The concept is verified by both simulation and in a 1kW Vienna rectifier experimental setup.
Devinda Anushka Molligoda; Salvador Ceballos; Josep Pou; Kuntal Satpathi; Firman Sasongko; Chandana Jayampathi Gajanayake; Amit Kumar Gupta. Hybrid Modulation Strategy for the Vienna Rectifier. IEEE Transactions on Power Electronics 2021, PP, 1 -1.
AMA StyleDevinda Anushka Molligoda, Salvador Ceballos, Josep Pou, Kuntal Satpathi, Firman Sasongko, Chandana Jayampathi Gajanayake, Amit Kumar Gupta. Hybrid Modulation Strategy for the Vienna Rectifier. IEEE Transactions on Power Electronics. 2021; PP (99):1-1.
Chicago/Turabian StyleDevinda Anushka Molligoda; Salvador Ceballos; Josep Pou; Kuntal Satpathi; Firman Sasongko; Chandana Jayampathi Gajanayake; Amit Kumar Gupta. 2021. "Hybrid Modulation Strategy for the Vienna Rectifier." IEEE Transactions on Power Electronics PP, no. 99: 1-1.
In the operation of cascaded H-bridge (CHB) converters and modular multilevel converters (MMCs) with energy storage or renewable power resources, unbalanced active power distribution among the submodules (SMs) is unavoidable. Depending on the operating conditions, there are certain upper and lower limits on the active power that can be processed by a single SM or a subset of SMs. The control system needs to restrict the SM power references to these limits, hence, accurate knowledge of the power limits is important. In existing methods to derive the power limits, the SM capacitor voltages are assumed to have negligible ripples, whereas in practice the ripples can be considerable. This paper analyzes the effect of capacitor voltage ripples on the SM active power control limits and highlights the importance of considering the ripple effect. A methodology is proposed to accurately incorporate capacitor voltage ripples in the derivation of SM active power control limits. Simulation and experimental results are provided to evaluate the effectiveness of the proposed methodology.
Gaowen Liang; Hossein Dehghani Tafti; Glen Ghias Farivar; Josep Pou; Christopher Townsend; Georgios Konstantinou; Salvador Ceballos. Effect of Capacitor Voltage Ripples on Submodule Active Power Control Limits of Cascaded Multilevel Converters. IEEE Transactions on Industrial Electronics 2021, PP, 1 -1.
AMA StyleGaowen Liang, Hossein Dehghani Tafti, Glen Ghias Farivar, Josep Pou, Christopher Townsend, Georgios Konstantinou, Salvador Ceballos. Effect of Capacitor Voltage Ripples on Submodule Active Power Control Limits of Cascaded Multilevel Converters. IEEE Transactions on Industrial Electronics. 2021; PP (99):1-1.
Chicago/Turabian StyleGaowen Liang; Hossein Dehghani Tafti; Glen Ghias Farivar; Josep Pou; Christopher Townsend; Georgios Konstantinou; Salvador Ceballos. 2021. "Effect of Capacitor Voltage Ripples on Submodule Active Power Control Limits of Cascaded Multilevel Converters." IEEE Transactions on Industrial Electronics PP, no. 99: 1-1.
Abstract--- This paper presents a constrained model predictive control (MPC) strategy for a three-phase low-capacitance static compensator (LC-StatCom) with delta configuration. The controller consists of an outer loop that provides dynamic references for the active grid current component and the circulating current; whereas the inner predictive loop minimises the quadratic error of state variables subject to operating limit conditions, thus providing optimal control signals that produce a fast response while guaranteeing the prescribed safe operating limit conditions. The paper also proposes an enhanced discrete-time model, which uses intersample values, that improves the accuracy of the model predictions when the sampling rate is not high enough to assume constant state variables. As a result, it facilitates the implementation of MPC on less powerful processors compared to the conventional modeling. The proposed control is especially suited for the LC-StatComs since it incorporates analytical computation of desired steady-state trajectories, which takes into account the induced oscillation on the capacitor voltages that are inherent to the LC-StatComs. The proposed approach has been verified by simulation and experimentally with a laboratory prototype.
Ezequiel Ramos Rodriguez; Ramon Leyva; Christopher David Townsend; Glen Ghias Farivar; Hossein Dehghani Tafti; Josep Pou. Constrained Control of Low-Capacitance Delta Cascaded H-Bridge StatComs: A Model Predictive Control Approach. IEEE Transactions on Power Electronics 2021, 36, 14312 -14328.
AMA StyleEzequiel Ramos Rodriguez, Ramon Leyva, Christopher David Townsend, Glen Ghias Farivar, Hossein Dehghani Tafti, Josep Pou. Constrained Control of Low-Capacitance Delta Cascaded H-Bridge StatComs: A Model Predictive Control Approach. IEEE Transactions on Power Electronics. 2021; 36 (12):14312-14328.
Chicago/Turabian StyleEzequiel Ramos Rodriguez; Ramon Leyva; Christopher David Townsend; Glen Ghias Farivar; Hossein Dehghani Tafti; Josep Pou. 2021. "Constrained Control of Low-Capacitance Delta Cascaded H-Bridge StatComs: A Model Predictive Control Approach." IEEE Transactions on Power Electronics 36, no. 12: 14312-14328.
Model predictive control has emerged as a promising approach to govern modular multilevel converters (MMCs), due to its flexibility to include multiple control objectives and simple design process. However, this control scheme presents relevant issues, such as high computational complexity and variable switching frequency. This work proposes a sequential phase-shifted model predictive control (PS-MPC) for MMCs. The key novelty of this proposal lies in the way the predictive control strategy is formulated to fully exploit a phase-shifted pulsewidth modulation technique, by means of an appropriate choice of synchronized average models for each carrier. In this way, the proposed predictive controller obtains independent optimal modulating signals for each carrier in a sequential manner, by solving an optimization problem with reduced computational effort independent of the number of submodules. This allows one to formulate the optimal control problem to achieve multiple control objectives, similarly to the finite-control-set MPC (FCS-MPC). Nevertheless, the MMC governed with the proposed PS-MPC generates an output voltage with fix-spectrum and operates with an even power loss distribution among semiconductors in steady-state, outperforming the standard FCS-MPC strategy. Experimental results are provided to verify the proposed PS-MPC effectiveness when governing a three-phase MMC with four half-bridges per stack.
Pablo Poblete; Sebastian Neira; Ricardo P. Aguilera; Javier Pereda; Josep Pou. Sequential Phase-Shifted Model Predictive Control for Modular Multilevel Converters. IEEE Transactions on Energy Conversion 2021, PP, 1 -1.
AMA StylePablo Poblete, Sebastian Neira, Ricardo P. Aguilera, Javier Pereda, Josep Pou. Sequential Phase-Shifted Model Predictive Control for Modular Multilevel Converters. IEEE Transactions on Energy Conversion. 2021; PP (99):1-1.
Chicago/Turabian StylePablo Poblete; Sebastian Neira; Ricardo P. Aguilera; Javier Pereda; Josep Pou. 2021. "Sequential Phase-Shifted Model Predictive Control for Modular Multilevel Converters." IEEE Transactions on Energy Conversion PP, no. 99: 1-1.
The increasing importance of cascaded multilevel converters (CMCs), and the sub-category of modular multilevel converters (MMCs), is illustrated by their wide use in high voltage DC connections and in static compensators. Research is being undertaken into the use of these complex pieces of hardware and software for a variety of grid support services, on top of fundamental frequency power injection, requiring improved control for non-traditional duties. To validate these results, small-scale laboratory hardware prototypes are often required. Such systems have been built by many research teams around the globe and are also increasingly commercially available. Few publications go into detail on the construction options for prototype CMCs, and there is a lack of information on both design considerations and lessons learned from the build process, which will hinder research and the best application of these important units. This paper reviews options, gives key examples from leading research teams, and summarizes knowledge gained in the development of test rigs to clarify design considerations when constructing laboratory-scale CMCs.
Theodor Heath; Mike Barnes; Paul D. Judge; Geraint Chaffey; Phil Clemow; Tim C. Green; Peter R. Green; James Wylie; Georgios Konstantinou; Salvador Ceballos; Josep Pou; Mohamed Moez Belhaouane; Haibo Zhang; Xavier Guillaud; Jack Andrews. Cascaded- and Modular-Multilevel Converter Laboratory Test System Options: A Review. IEEE Access 2021, 9, 44718 -44737.
AMA StyleTheodor Heath, Mike Barnes, Paul D. Judge, Geraint Chaffey, Phil Clemow, Tim C. Green, Peter R. Green, James Wylie, Georgios Konstantinou, Salvador Ceballos, Josep Pou, Mohamed Moez Belhaouane, Haibo Zhang, Xavier Guillaud, Jack Andrews. Cascaded- and Modular-Multilevel Converter Laboratory Test System Options: A Review. IEEE Access. 2021; 9 ():44718-44737.
Chicago/Turabian StyleTheodor Heath; Mike Barnes; Paul D. Judge; Geraint Chaffey; Phil Clemow; Tim C. Green; Peter R. Green; James Wylie; Georgios Konstantinou; Salvador Ceballos; Josep Pou; Mohamed Moez Belhaouane; Haibo Zhang; Xavier Guillaud; Jack Andrews. 2021. "Cascaded- and Modular-Multilevel Converter Laboratory Test System Options: A Review." IEEE Access 9, no. : 44718-44737.
This paper presents a control strategy for a dual-input neutral-point-clamped (NPC) inverter-based grid-connected photovoltaic (PV) system to asymmetrically control the PV arrays without incorporating any additional external circuit. This is achieved by employing an analytically developed linearization block, which helps in generating the required neutral point (NP) current to counter for the difference in the PV currents. The analysis also provides the maximum NP current compensation limits of the NPC inverter. If the required NP current reference is less than the maximum limit, both PV arrays operate at their maximum power points. However, if the required current exceeds the limit, one of the PV arrays operates at its maximum power point (MPP) while the output power of the other PV array is reduced to satisfy the NP current limit. Experimental tests are conducted on a laboratory prototype to validate the performance of the proposed control strategy.
Neha Beniwal; Hossein Dehghani Tafti; Glen Ghias Farivar; Salvador Ceballos; Josep Pou; Frede Ge Blaabjerg. A Control Strategy for Dual-Input Neutral-Point-Clamped Inverter-Based Grid-Connected Photovoltaic System. IEEE Transactions on Power Electronics 2021, 36, 9743 -9757.
AMA StyleNeha Beniwal, Hossein Dehghani Tafti, Glen Ghias Farivar, Salvador Ceballos, Josep Pou, Frede Ge Blaabjerg. A Control Strategy for Dual-Input Neutral-Point-Clamped Inverter-Based Grid-Connected Photovoltaic System. IEEE Transactions on Power Electronics. 2021; 36 (9):9743-9757.
Chicago/Turabian StyleNeha Beniwal; Hossein Dehghani Tafti; Glen Ghias Farivar; Salvador Ceballos; Josep Pou; Frede Ge Blaabjerg. 2021. "A Control Strategy for Dual-Input Neutral-Point-Clamped Inverter-Based Grid-Connected Photovoltaic System." IEEE Transactions on Power Electronics 36, no. 9: 9743-9757.
The cascaded H-bridge (CHB) low-capacitance stat- ic compensator (LC-StatCom) has a limited operating range in the inductive region compared to a conventional StatCom due to the inherent large oscillations on the capacitor voltages. This lim- itation constitutes a great drawback of CHB LC-StatComs. This paper presents an effective hardware-free solution to overcome this drawback. The proposed solution is based on the injection of an optimal third harmonic circulating current to suitably shape the capacitor voltages aiming at avoiding overmodulation. Considering all the effects of the third harmonic circulating current, the paper proposes a reference design that guarantees a prescribed safe operating voltage limit, thus increasing the oper- ational range of the LC-StatCom. The proposed approach takes into account the inherent induced oscillation on the capacitor voltages. This approach has been verified by simulation and experimentally with a laboratory prototype, corroborating the excellent performance that agrees with the theoretical analysis.
Ezequiel Ramos Rodriguez; Ramon Leyva; Qingxiang Liu; Christopher David Townsend; Glen Ghias Farivar; Salvador Ceballos; Josep Pou. Enhancing Inductive Operation of Low-Capacitance Cascaded H-Bridge StatComs Using Optimal Third-Harmonic Circulating Current. IEEE Transactions on Power Electronics 2021, 36, 10788 -10800.
AMA StyleEzequiel Ramos Rodriguez, Ramon Leyva, Qingxiang Liu, Christopher David Townsend, Glen Ghias Farivar, Salvador Ceballos, Josep Pou. Enhancing Inductive Operation of Low-Capacitance Cascaded H-Bridge StatComs Using Optimal Third-Harmonic Circulating Current. IEEE Transactions on Power Electronics. 2021; 36 (9):10788-10800.
Chicago/Turabian StyleEzequiel Ramos Rodriguez; Ramon Leyva; Qingxiang Liu; Christopher David Townsend; Glen Ghias Farivar; Salvador Ceballos; Josep Pou. 2021. "Enhancing Inductive Operation of Low-Capacitance Cascaded H-Bridge StatComs Using Optimal Third-Harmonic Circulating Current." IEEE Transactions on Power Electronics 36, no. 9: 10788-10800.
The modular multilevel converter (MMC) is currently one of the power converter topologies which has attracted more research and development worldwide. Its features, such as high quality of voltages and currents, high modularity and high voltage rating, have made the MMC a very good option for several applications including high-voltage dc (HVdc) transmission, static compensators (STATCOMs), and motor drives. However, its unique features such as the large number of submodules, floating capacitor voltages, and circulating currents require a dedicated control system able to manage the terminal variables, as well as the internal variables with high dynamical performance. In this paper, a review of the research and development achieved during the last years on MMCs is shown, focusing on the challenges and proposed solutions for this power converter still faces in terms of modeling, control, reliability, power topologies, and new applications.
Marcelo A. Perez; Salvador Ceballos; Georgios Konstantinou; Josep Pou; Ricardo P. Aguilera. Modular Multilevel Converters: Recent Achievements and Challenges. IEEE Open Journal of the Industrial Electronics Society 2021, 2, 224 -239.
AMA StyleMarcelo A. Perez, Salvador Ceballos, Georgios Konstantinou, Josep Pou, Ricardo P. Aguilera. Modular Multilevel Converters: Recent Achievements and Challenges. IEEE Open Journal of the Industrial Electronics Society. 2021; 2 ():224-239.
Chicago/Turabian StyleMarcelo A. Perez; Salvador Ceballos; Georgios Konstantinou; Josep Pou; Ricardo P. Aguilera. 2021. "Modular Multilevel Converters: Recent Achievements and Challenges." IEEE Open Journal of the Industrial Electronics Society 2, no. : 224-239.
Grid-connected photovoltaic (PV) systems impose challenges like voltage fluctuations, low system inertia and power quality issues. The need to tackle these challenges led to the introduction of flexible power point tracking (FPPT), where the PV power output is controlled by an energy management system (EMS), rather than solely operating the PV systems on the maximum power point (MPP). The requirement of fast transient response implies that algorithms such as the one proposed in this paper are desirable. The proposed algorithm uses the secant method to achieve significantly improved results in comparison to the existing methods. The method also simplifies the prediction of variations during changes in the environment and power reference, hence, results in reduced oscillation around the set-point and faster convergence. Experimental validation is presented in this paper for supporting the claims. The results in terms of accuracy, convergence rate, steady state oscillations and cumulative error are bench-marked against one of the most recent FPPT methods.
Anusha Kumaresan; Hossein Dehghani Tafti; Nandha Kumar Kandasamy; Glen Ghias Farivar; Josep Pou; Thangavel Subbaiyan. Flexible Power Point Tracking for Solar Photovoltaic Systems Using Secant Method. IEEE Transactions on Power Electronics 2021, 36, 9419 -9429.
AMA StyleAnusha Kumaresan, Hossein Dehghani Tafti, Nandha Kumar Kandasamy, Glen Ghias Farivar, Josep Pou, Thangavel Subbaiyan. Flexible Power Point Tracking for Solar Photovoltaic Systems Using Secant Method. IEEE Transactions on Power Electronics. 2021; 36 (8):9419-9429.
Chicago/Turabian StyleAnusha Kumaresan; Hossein Dehghani Tafti; Nandha Kumar Kandasamy; Glen Ghias Farivar; Josep Pou; Thangavel Subbaiyan. 2021. "Flexible Power Point Tracking for Solar Photovoltaic Systems Using Secant Method." IEEE Transactions on Power Electronics 36, no. 8: 9419-9429.
Employing interleaved techniques in dc-dc converters provides fault-tolerant capability to the faulted switches of the converter. In the case of one phase failure, the other phases can continue operating. However, in interleaved topologies, if the output power is maintained at the desired constant value for post-fault conditions, there is a saturation risk of inductors. In this letter, a post-fault reconfiguration process for the three-phase interleaved dc-dc converter is proposed, which guarantees the operation of the inductor without saturation risk after power switch failures. The reconfiguration steps do not require isolating the inductor of the corresponding faulty phase. Experimental results of the presented converter verify the operation of the inductor without saturation and the effectiveness of the proposed strategy.
Tohid Rahimi; Lei Ding; Rasoul Faraji; Mostafa Kheshti; Josep Pou. Performance Improvement of a Three-Phase Interleaved DC–DC Converter Without Requiring Antisaturation Control for Postfault Conditions. IEEE Transactions on Power Electronics 2020, 36, 7378 -7383.
AMA StyleTohid Rahimi, Lei Ding, Rasoul Faraji, Mostafa Kheshti, Josep Pou. Performance Improvement of a Three-Phase Interleaved DC–DC Converter Without Requiring Antisaturation Control for Postfault Conditions. IEEE Transactions on Power Electronics. 2020; 36 (7):7378-7383.
Chicago/Turabian StyleTohid Rahimi; Lei Ding; Rasoul Faraji; Mostafa Kheshti; Josep Pou. 2020. "Performance Improvement of a Three-Phase Interleaved DC–DC Converter Without Requiring Antisaturation Control for Postfault Conditions." IEEE Transactions on Power Electronics 36, no. 7: 7378-7383.
This paper presents a new finite control set model predictive control strategy that, contrary to conventional approaches, achieves (i) zero steady-state error in the converter’s AC current, and (ii) both fixed and lower harmonic spectrum, similar to that achieved by pulse width modulation based control schemes. These characteristics are attractive for medium and high voltage applications where high dv/dt is prohibitive and reduced switching losses are a must, or in applications that use passive filters and where a spread harmonic spectrum can cause resonances. The proposed strategy achieves dynamic results similar to those of conventional predictive control and a steady-state performance similar to that of a modulated control strategy. To do so, the strategy utilizes a modulated integral action to incorporate an input restriction into a conventional predictive control cost function. A grid-connected cascaded H-Bridge multilevel inverter is used to validate the strategy. Simulated and experimental results in both steady and transient states are presented to verify the proposed strategy’s performance in the converter.
Roberto O. Ramirez; Carlos R. Baier; Felipe Villarroel; Jose R. Espinoza; Josep Pou; Jose Rodriguez. A Hybrid FCS-MPC With Low and Fixed Switching Frequency Without Steady-State Error Applied to a Grid-Connected CHB Inverter. IEEE Access 2020, 8, 223637 -223651.
AMA StyleRoberto O. Ramirez, Carlos R. Baier, Felipe Villarroel, Jose R. Espinoza, Josep Pou, Jose Rodriguez. A Hybrid FCS-MPC With Low and Fixed Switching Frequency Without Steady-State Error Applied to a Grid-Connected CHB Inverter. IEEE Access. 2020; 8 (99):223637-223651.
Chicago/Turabian StyleRoberto O. Ramirez; Carlos R. Baier; Felipe Villarroel; Jose R. Espinoza; Josep Pou; Jose Rodriguez. 2020. "A Hybrid FCS-MPC With Low and Fixed Switching Frequency Without Steady-State Error Applied to a Grid-Connected CHB Inverter." IEEE Access 8, no. 99: 223637-223651.
This paper presents a dual-mode modulation technique which aims to control the average current flow into the neutral point (NP) of the neutral-point-clamped (NPC) converter without the need for any additional hardware. The two modes of operation are normal mode and compensating mode. In the normal operation mode, all the three phases switch between two consecutive voltage levels (between the positive or negative dc-rail and the neutral point) in a switching period. In the compensating operation mode, at least one of the phases switches between the positive and negative dc-rails in a switching period. An analytical solution is developed to determine the duration of these two operation modes within each fundamental cycle based on the converter's operating condition. An advantage of this solution is that it can be generalized for balancing the capacitor voltages in all applications employing NPC converters. The proposed solution also determines the maximum average NP current injection capacity of the NPC converter under dual-mode modulation technique, which indicates the stable operating range of the converter. The performance of the proposed modulation technique is validated experimentally for various loading conditions.
Neha Beniwal; Glen Ghias Farivar; Hossein Dehghani Tafti; Josep Pou; Salvador Ceballos; Georgios Konstantinou; Christopher David Townsend. A Dual-Mode Modulation Technique for Controlling the Average Neutral Point Current in Neutral-Point-Clamped Converters. IEEE Transactions on Power Electronics 2020, 36, 6079 -6091.
AMA StyleNeha Beniwal, Glen Ghias Farivar, Hossein Dehghani Tafti, Josep Pou, Salvador Ceballos, Georgios Konstantinou, Christopher David Townsend. A Dual-Mode Modulation Technique for Controlling the Average Neutral Point Current in Neutral-Point-Clamped Converters. IEEE Transactions on Power Electronics. 2020; 36 (5):6079-6091.
Chicago/Turabian StyleNeha Beniwal; Glen Ghias Farivar; Hossein Dehghani Tafti; Josep Pou; Salvador Ceballos; Georgios Konstantinou; Christopher David Townsend. 2020. "A Dual-Mode Modulation Technique for Controlling the Average Neutral Point Current in Neutral-Point-Clamped Converters." IEEE Transactions on Power Electronics 36, no. 5: 6079-6091.
Due to a dramatic increase in grid-connected renewable energy resources, energy storage systems (ESSs) are believed to be a must in future power systems, among which the modular multilevel converter (MMC)-based battery energy storage systems (BESSs) are one of the most modular, efficient and flexible topologies. Uneven active power distribution among sub-modules (SMs) in the arms of an MMC-based BESS is necessary in certain applications. The main contribution of this paper is to present a general analysis of the inter-SM active power disparity problem which incorporates the inherent operational constraints of the MMC converter. An analytical method to derive inter-SM active power disparity limits is introduced. The proposed analysis can help facilitate the design of MMC-based BESS for applications such as recycled batteries and hybrid battery chemistries, which can both require significant inter-SM active power disparity. The analysis formulates a criteria vector and criterion value that describes whether an MMC-based BESS is capable of supplying demanded output powers while subject to inter-SM active power disparity. Simulation and experimental results are obtained on a single-phase system with varying numbers of SMs per arm, which verifies the feasibility and generality of the proposed analytic method.
Gaowen Liang; Hossein Dehghani Tafti; Glen Ghias Farivar; Josep Pou; Christopher David Townsend; Georgios Konstantinou; Salvador Ceballos. Analytical Derivation of Intersubmodule Active Power Disparity Limits in Modular Multilevel Converter-Based Battery Energy Storage Systems. IEEE Transactions on Power Electronics 2020, 36, 2864 -2874.
AMA StyleGaowen Liang, Hossein Dehghani Tafti, Glen Ghias Farivar, Josep Pou, Christopher David Townsend, Georgios Konstantinou, Salvador Ceballos. Analytical Derivation of Intersubmodule Active Power Disparity Limits in Modular Multilevel Converter-Based Battery Energy Storage Systems. IEEE Transactions on Power Electronics. 2020; 36 (3):2864-2874.
Chicago/Turabian StyleGaowen Liang; Hossein Dehghani Tafti; Glen Ghias Farivar; Josep Pou; Christopher David Townsend; Georgios Konstantinou; Salvador Ceballos. 2020. "Analytical Derivation of Intersubmodule Active Power Disparity Limits in Modular Multilevel Converter-Based Battery Energy Storage Systems." IEEE Transactions on Power Electronics 36, no. 3: 2864-2874.
Ezequiel Rodriguez Ramos; Ramon Leyva; Glen G. Farivar; Hossein Dehghani Tafti; Christopher D. Townsend; Josep Pou. Incremental Passivity Control in Multilevel Cascaded H-Bridge Converters. IEEE Transactions on Power Electronics 2020, 35, 8766 -8778.
AMA StyleEzequiel Rodriguez Ramos, Ramon Leyva, Glen G. Farivar, Hossein Dehghani Tafti, Christopher D. Townsend, Josep Pou. Incremental Passivity Control in Multilevel Cascaded H-Bridge Converters. IEEE Transactions on Power Electronics. 2020; 35 (8):8766-8778.
Chicago/Turabian StyleEzequiel Rodriguez Ramos; Ramon Leyva; Glen G. Farivar; Hossein Dehghani Tafti; Christopher D. Townsend; Josep Pou. 2020. "Incremental Passivity Control in Multilevel Cascaded H-Bridge Converters." IEEE Transactions on Power Electronics 35, no. 8: 8766-8778.
Glen G. Farivar; Christopher D. Townsend; Hossein Dehghani Tafti; Young-Tae Jeon; Ezequiel R. Ramos; Josep Pou; Branislav Hredzak. Cascaded H-Bridge Low Capacitance Static Compensator With Modular Switched Capacitors. IEEE Transactions on Industrial Electronics 2020, 68, 5944 -5954.
AMA StyleGlen G. Farivar, Christopher D. Townsend, Hossein Dehghani Tafti, Young-Tae Jeon, Ezequiel R. Ramos, Josep Pou, Branislav Hredzak. Cascaded H-Bridge Low Capacitance Static Compensator With Modular Switched Capacitors. IEEE Transactions on Industrial Electronics. 2020; 68 (7):5944-5954.
Chicago/Turabian StyleGlen G. Farivar; Christopher D. Townsend; Hossein Dehghani Tafti; Young-Tae Jeon; Ezequiel R. Ramos; Josep Pou; Branislav Hredzak. 2020. "Cascaded H-Bridge Low Capacitance Static Compensator With Modular Switched Capacitors." IEEE Transactions on Industrial Electronics 68, no. 7: 5944-5954.
Bin Guo; Mei Su; Yao Sun; Hui Wang; Bin Liu; Xin Zhang; Josep Pou; Yongheng Yang; Pooya Davari. Optimization Design and Control of Single-Stage Single-Phase PV Inverters for MPPT Improvement. IEEE Transactions on Power Electronics 2020, 35, 13000 -13016.
AMA StyleBin Guo, Mei Su, Yao Sun, Hui Wang, Bin Liu, Xin Zhang, Josep Pou, Yongheng Yang, Pooya Davari. Optimization Design and Control of Single-Stage Single-Phase PV Inverters for MPPT Improvement. IEEE Transactions on Power Electronics. 2020; 35 (12):13000-13016.
Chicago/Turabian StyleBin Guo; Mei Su; Yao Sun; Hui Wang; Bin Liu; Xin Zhang; Josep Pou; Yongheng Yang; Pooya Davari. 2020. "Optimization Design and Control of Single-Stage Single-Phase PV Inverters for MPPT Improvement." IEEE Transactions on Power Electronics 35, no. 12: 13000-13016.
The power system is experiencing an ever-increasing integration of photovoltaic power plants (PVPPs), which leads demand on the power system operators to force new requirements to sustain with quality and reliability of the grid. Subsequently, a significant quantity of flexible power point tracking (FPPT) algorithms have been proposed in the literature to enhance functionalities PVPPs. The intention of FPPT algorithms is to regulate the PV power to a specific value imposed by the grid codes and operational conditions. This will inevitably interfere the maximum power point tracking (MPPT) operation of PV systems. Nevertheless, the FPPT control makes PVPPs much more grid-friendly. The main contribution of this paper is to comprehensively compare available FPPT algorithms in the literature from different aspects and provide a benchmark for researchers and engineers to select suitable FPPT algorithms for specific applications. A classification and short description of them are provided. The dynamic performances of the investigated algorithms are compared with experimental tests on a scaled-down prototype. Directions for future studies in this area are also presented.
Hossein Dehghani Tafti; Georgios Konstantinou; Christopher David Townsend; Glen Ghias Farivar; Ariya Sangwongwanich; Yongheng Yang; Josep Pou; Frede Blaabjerg. Extended Functionalities of Photovoltaic Systems With Flexible Power Point Tracking: Recent Advances. IEEE Transactions on Power Electronics 2020, 35, 9342 -9356.
AMA StyleHossein Dehghani Tafti, Georgios Konstantinou, Christopher David Townsend, Glen Ghias Farivar, Ariya Sangwongwanich, Yongheng Yang, Josep Pou, Frede Blaabjerg. Extended Functionalities of Photovoltaic Systems With Flexible Power Point Tracking: Recent Advances. IEEE Transactions on Power Electronics. 2020; 35 (9):9342-9356.
Chicago/Turabian StyleHossein Dehghani Tafti; Georgios Konstantinou; Christopher David Townsend; Glen Ghias Farivar; Ariya Sangwongwanich; Yongheng Yang; Josep Pou; Frede Blaabjerg. 2020. "Extended Functionalities of Photovoltaic Systems With Flexible Power Point Tracking: Recent Advances." IEEE Transactions on Power Electronics 35, no. 9: 9342-9356.
In this paper, a band-limited three-level modulation scheme is proposed for a three-phase NPC converter with an aim to balance the average capacitor voltages under all operating conditions. When conventional CBPWM is applied, the amplitude of NP voltage ripple tends to increase under linear imbalances, while the NP voltage can shift leading to instability in the presence of nonlinear loads. A previously proposed three-level modulation scheme was able to eliminate all low-frequency capacitor voltage ripple by switching a phase between three levels in each switching period. This approach significantly increased switching loss. The proposed modulation scheme limits the increase in switching loss by employing two operational bands, one fixed band applied to the capacitor voltages and another variable band applied to the phase currents. If the instantaneous capacitor voltages exceed the voltage band, then an appropriate phase-leg is switched in three-levels to guarantee the capacitor voltages cannot diverge further. If the instantaneous capacitor voltages reside within the voltage band, a variable current band is used to regulate switching in three voltage levels in order to obtain lower switching losses as compared to the conventional three-level modulation scheme. The proposed modulation scheme presents trade-off between switching losses and capacitor voltage ripple.
Neha Beniwal; Christopher David Townsend; Glen Ghias Farivar; Josep Pou; Salvador Ceballos; Hossein Dehghani Tafti. Band-Limited Three-Level Modulation for Balancing Capacitor Voltages in Neutral-Point-Clamped Converters. IEEE Transactions on Power Electronics 2020, 35, 9737 -9752.
AMA StyleNeha Beniwal, Christopher David Townsend, Glen Ghias Farivar, Josep Pou, Salvador Ceballos, Hossein Dehghani Tafti. Band-Limited Three-Level Modulation for Balancing Capacitor Voltages in Neutral-Point-Clamped Converters. IEEE Transactions on Power Electronics. 2020; 35 (9):9737-9752.
Chicago/Turabian StyleNeha Beniwal; Christopher David Townsend; Glen Ghias Farivar; Josep Pou; Salvador Ceballos; Hossein Dehghani Tafti. 2020. "Band-Limited Three-Level Modulation for Balancing Capacitor Voltages in Neutral-Point-Clamped Converters." IEEE Transactions on Power Electronics 35, no. 9: 9737-9752.
Ezequiel Rodriguez; Glen G. Farivar; Neha Beniwal; Christopher D. Townsend; Hossein Dehghani Tafti; Sergio Vazquez; Josep Pou. Closed-Loop Analytic Filtering Scheme of Capacitor Voltage Ripple in Multilevel Cascaded H-Bridge Converters. IEEE Transactions on Power Electronics 2020, 35, 8819 -8832.
AMA StyleEzequiel Rodriguez, Glen G. Farivar, Neha Beniwal, Christopher D. Townsend, Hossein Dehghani Tafti, Sergio Vazquez, Josep Pou. Closed-Loop Analytic Filtering Scheme of Capacitor Voltage Ripple in Multilevel Cascaded H-Bridge Converters. IEEE Transactions on Power Electronics. 2020; 35 (8):8819-8832.
Chicago/Turabian StyleEzequiel Rodriguez; Glen G. Farivar; Neha Beniwal; Christopher D. Townsend; Hossein Dehghani Tafti; Sergio Vazquez; Josep Pou. 2020. "Closed-Loop Analytic Filtering Scheme of Capacitor Voltage Ripple in Multilevel Cascaded H-Bridge Converters." IEEE Transactions on Power Electronics 35, no. 8: 8819-8832.