- 标题
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- 实验方案
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Impact of Grid Voltage Feed-Forward Filters on Coupling between DC-Link Voltage and AC Voltage Controllers in Smart PV Solar Systems
摘要： This paper presents a novel study of impact of filters of grid voltage feed-forward signals on the coupling between dc-link voltage and ac voltage controllers in smart photovoltaic (PV) solar systems which are used for voltage control in distribution systems. A comprehensive linearized state space model of a PV system including the dynamics of grid voltage feed-forward filters, dc-link voltage and ac voltage controllers is developed for the first time. This model is validated by electromagnetic transients software PSCAD/EMTDC. This model is used to identify the coupling between dc-link voltage and ac voltage controllers by eigenvalue and participation factor analyses. The impact of time constant of feed-forward filters on this coupling is studied by eigenvalue sensitivity analysis for PV systems with Proportional and Proportional Integral type ac voltage controllers. The range of time constants over which the filters interact with controllers and create instability for systems with different strengths and X/R ratios is identified. Insights are provided on the choice of time constants of grid voltage feed-forward filters for stable system design. The developed state-space model can also be used for impact studies of various other parameters e.g. system strength, X/R ratios, types and gains of controllers, on system stability.
关键词： AC Voltage Control,Smart Inverter,Photovoltaic (PV) System,Reactive Power Control,Control Interaction
更新于2025-09-23 15:22:29
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Cooperative Operation of R-SFCL and Online Current Limitation Strategy of GCPVS under Asymmetrical Faults
摘要： Grid-connected photovoltaic (GCPVS) should remain grid-connected and inject specified reactive current in accordance with fault-ride-through (FRT) requirements. To minimize voltage ripples on the DC link voltage and restrict the maximum phase currents, a modified online current limitation strategy (OCLS) is presented in this paper. Transient performance of GCPVS is enhanced as resistive-type superconducting fault current limiter (R-SFCL) is applied under severe asymmetrical faults. By introducing proper resistance selection process, the cooperative operation of OCLS and SFCL is proved to be effective.
关键词： reactive power control,transient performance,superconducting fault current limiters (FCL),online current limitation strategy (OCLS),photovoltaic systems,Fault ride-through (FRT) capability,symmetrical and asymmetrical faults
更新于2025-09-23 15:22:29
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[IEEE 2019 IEEE 15th Brazilian Power Electronics Conference and 5th IEEE Southern Power Electronics Conference (COBEP/SPEC) - Santos, Brazil (2019.12.1-2019.12.4)] 2019 IEEE 15th Brazilian Power Electronics Conference and 5th IEEE Southern Power Electronics Conference (COBEP/SPEC) - Optimal Voltage Coordinated Control for Grid-connected Photovoltaic Systems
摘要： The intermittent penetration of Grid-connected photovoltaic systems and load changing in distribution feeders can cause voltage ?uctuation. This paper aims to analyze the performance of different power control strategies to avoid overvoltage in MV feeders. The strategies use Volt/Var control and Volt/Watt control techniques to ?nd the optimal active or reactive power to be injected/absorbed by the PV inverters with the aim to minimize the voltage deviation and power losses and also coordinate the grid-connected photovoltaic system with the voltage regulation devices of distribution feeders. The strategies are tested in the IEEE 13 node test feeder.
关键词： active and reactive power control,grid-connected photovoltaic systems,Voltage regulation
更新于2025-09-23 15:21:01
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Scheduling of PV inverter reactive power set-point and battery charge/discharge profile for voltage regulation in low voltage networks
摘要： In recent years, renewable energies and storage systems are bringing a significant contribution to power system. Due to the high penetration of non-predictable power sources, especially in the distribution networks, new challenges related to the integration and management of these new resources also combined with storage systems arose in power system research. Accordingly, the aim of this paper is to propose an innovative scheduling method for voltage regulation in low voltage networks. A simple type of contract for ancillary services that foresees the participation of active users endowed with a storage system coupled with a PV system is considered. The method allows to regulate the voltage in a distribution system by using a combined PV and storage system. The voltage regulation is achieved by setting the value of the inverter reactive power on the basis of sensitivity coefficients of the considered node, taking into account the capability curve constrains, as required by new grid codes. A possible tariff policy is also proposed for the ancillary service and for the operation of the realization of the scheduling algorithm. Simulation results demonstrate the effectiveness of the proposed method for the scheduling of the power system.
关键词： Voltage quality,Storage,Ancillary service,Reactive power control,Battery scheduling,Photovoltaic inverter
更新于2025-09-23 15:21:01
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3-Phase grid-connected building integrated photovoltaic system with reactive power control capability
摘要： Recently, a tendency in the growing of grid-connected building integrated photovoltaic (BIPV) systems has been noticed in most countries. Hence, high penetration of PV power into the system network can be observed in many points in the network. This may cause severe problems on the distribution network due to the intermittent nature of PV systems. As a feasible solution, the reactive power capability of voltage source inverter in PV systems can be employed rather than approaching expensive grid infrastructures in the distribution network. The purpose of this study is to implement a 3-phase grid-connected (BIPV) system with reactive power control to regulate the system voltage and improve the system power factor. Subsequent to this, a specific system model has been designed and developed in MATLAB Simulink application. The selection of PV system specifications is based on practical system implementation. The inverter control system along with the reactive power control has been developed for the proper system operation at different system conditions to reduce the var compensation on the utility grid. Better system accuracy of the developed system model has been found by validating with real system data. The overall system performance has indicated that the effective utilization of reactive power control of a grid-connected PV system yields to a stable, reliable and cost-effective system network operation which reduces the heavy burden on the utility grid to control the PV system effects.
关键词： Reactive power control,Voltage source inverter,Grid-connected PV system,Voltage regulation
更新于2025-09-23 15:19:57
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[IEEE 2018 International Conference on Smart Grid and Clean Energy Technologies (ICSGCE) - Sg. Long, Cheras, Kajang, Malaysia (2018.5.29-2018.6.1)] 2018 International Conference on Smart Grid and Clean Energy Technologies (ICSGCE) - A Novel Five-Level Inverter Topology with Reactive Power Control for Grid-Connected PV System
摘要： These days multilevel inverters are more popular for grid-connected photovoltaic (PV) systems due to their low cost and high efficiency, as they effectively reduce total harmonic distortion (THD) and electromagnetic interference which results leakage current. Traditional multi-level inverters can only inject real power that cannot provide quality output power. A new international standard VDE-AR-N4105 states that for a grid tied inverter of power rating below 3.68kVA, a power factor (PF) of 0.95 leading to 0.95 lagging should be achieved. So, in this paper the proposed five-level inverter topology for grid-tie PV is controlled using a reactive power control method that ensures higher efficiency while enhancing the stability of the system. The proposed closed loop reactive power control technique additionally provides the ability to inject reactive power into the system. In this proposed topology the reactive power flow standard of operation is explained in details in relation to the proposed multi-level inverter topology. To validate the accuracy of the theoretical analysis, the control technique was applied to the existing multi-level inverter topology and then has been simulated in MATLAB/Simulink software. Comparisons were done on the basis of using and not using PLL for the existing multilevel topology and it is found that, synchronization is achieved with current and voltage if PLL is used, as a result PF is maintained close to unity whereas without PLL the PF decreases. Moreover the five-level output provides a much better output and better PF then other existing topologies.
关键词： phase-locked loop (PLL),multi-level inverters,solar PV,reactive power control
更新于2025-09-23 15:19:57
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Direct Synthesis and Design of Dispersive Waveguide Bandpass Filters
摘要： Wireless power transfer (WPT) is an emerging technology with an increasing number of potential applications to transfer power from a transmitter to a mobile receiver over a relatively large air gap. However, its widespread application is hampered due to the relatively low efficiency of current Wireless power transfer (WPT) systems. This study presents a concept to maximize the efficiency as well as to increase the amount of extractable power of a WPT system operating in nonresonant operation. The proposed method is based on actively modifying the equivalent secondary-side load impedance by controlling the phase-shift of the active rectifier and its output voltage level. The presented hardware prototype represents a complete wireless charging system, including a dc–dc converter which is used to charge a battery at the output of the system. Experimental results are shown for the proposed concept in comparison to a conventional synchronous rectification approach. The presented optimization method clearly outperforms state-of-the-art solutions in terms of efficiency and extractable power.
关键词： wireless charging,inductive power transmission,Dc-dc power converters,reactive power control,phase-shift control,rectifiers,impedance matching
更新于2025-09-19 17:13:59
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Coordinated reactive power strategy using static synchronous compensator for photovoltaic inverters
摘要： Large photovoltaic (PV) penetrations into the electric grid resulted in new challenges such as reverse power flow and violation of voltage profile. The traditional methods for voltage regulation in a grid-connected PV system are hardly adaptable to these changes as they only contain the local information which is used without the knowledge of how the control action affects the overall system. To address this problem, this paper extends the reactive power control capability of solar PV inverters by combining them with static power electronic devices for regulating voltage during grid faults. For efficient identification of grid faults, a support vector machine-based fault classification mechanism is developed. The proposed method prioritizes the reactive power control using PV inverter by adapting a predefined hierarchical control structure. The complete methodology is realized by testing it with a two-stage single-phase grid-connected PV system. The experimental results verify the accuracy of the classification algorithm and depict the effectiveness of the proposed controller in both under and overvoltage situations.
关键词： fault ride through (FRT),reactive power control,islanding classification,grid-connected photovoltaic system (GCPVS)
更新于2025-09-19 17:13:59
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A review on voltage control for distribution systems with large-scale distributed photovoltaic power integration
摘要： In order to solve the problems of voltage wide-range fluctuations and over-limitation after large-scale distributed photovoltaic (DPV) integrated into distribution networks, this paper conducts a comprehensive and detailed analysis of voltage control strategy by summarizing existing voltage control technology and experience at home and abroad. The technical points and a comprehensive comparison from the perspectives of active power curtailment (APC), reactive power control (RPC) and active-reactive power coordination control (A/RC) are made. Through comparative analysis, it is found that adopting active-reactive power coordination control is a key measure to effectively improve voltage quality and increase the PV hosting capacity of distribution networks. The optimization of the control strategy can effectively improve the friendliness of large-scale PV system integration. The method and control strategy can provide a theoretical basis and practical reference for voltage management of distribution networks with high penetration PV integration.
关键词： reactive power control,active-reactive power coordination control,distributed photovoltaic power,voltage control,active power curtailment,distribution systems
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE PES Innovative Smart Grid Technologies Europe (ISGT-Europe) - Bucharest, Romania (2019.9.29-2019.10.2)] 2019 IEEE PES Innovative Smart Grid Technologies Europe (ISGT-Europe) - Multi-layer Reactive Power Control of Solar Photovoltaic Systems in MV Distribution Network
摘要： The growing penetration of photovoltaic (PV) systems in distribution networks causes various power quality issues e.g. voltage rise, network losses. To deal with the overvoltage, inverter-based reactive power contribution is one of the most commonly proposed approaches. However, using standard strategies with fixed droop parameters limits the control effectiveness. Moreover, much reactive power absorbed by PVs around noon might increase the network loss, overload the substation consequently, especially in the network with long distribution feeders. In this paper, a combined centralized and local control method is proposed with the suggestion of multi-layer structure. Droop parameters of local control are updated every 15 min by centralized control to minimize reactive power flow through substation while keeping voltages in permitted levels. By avoiding overloading substation, more PV generation can be added to the feeder.
关键词： Reactive power control,droop control,particle swarm optimization,voltage control,photovoltaic (PV) systems
更新于2025-09-16 10:30:52