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- 摘要
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- 实验方案
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[IEEE 2019 22nd International Conference on Electrical Machines and Systems (ICEMS) - Harbin, China (2019.8.11-2019.8.14)] 2019 22nd International Conference on Electrical Machines and Systems (ICEMS) - Seamless Transfer Scheme Based on Unified Control Structure for Single-Stage Photovoltaic Inverter
摘要： The seamless transfer between islanded and grid-connected modes can be achieved by the voltage-type control inverter based on traditional droop control scheme. However, the grid current cannot be controlled directly when the inverter is connected to the grid, which shows that the grid current is easily distorted by the grid voltage harmonics. Moreover, the dynamics of the grid current may be slow under the traditional droop control. To resolve these issues, a novel seamless transfer scheme between two operation modes with unified control structure is proposed in this paper. Simulation results and experimental results are both presented, showing the feasibility of the proposed scheme.
关键词： Droop control,Seamless transfer,Photovoltaic inverter
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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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Reduced-order Aggregate Model for Parallel-connected Grid-tied Three-phase Photovoltaic Inverters
摘要： Ratings of utility-scale grid-tied photovoltaic (PV) inverters are typically no more than 1 MVA. This implies that a large number of inverters are usually installed in utility-scale PV energy-conversion systems. Given the complexity of inverter dynamic models (typical models are high dimension and nonlinear), reduced-order models for inverters are critical for performance assessment and accurate representation of PV-system dynamics in the bulk power grid with limited computational burden. In this paper, we formulate a reduced-order model for parallel-connected grid-tied three-phase PV inverters that has the same structure and model order as a single inverter. We adopt a single-diode model for the PV modules, and each inverter is assumed to be a single-stage dc-ac voltage-source converter with an input dc-link capacitor and an LCL output filter. The control architecture includes a maximum power point tracking (MPPT) algorithm, a dc-link voltage controller, a reactive power controller, a current controller, and a phase-locked loop for grid synchronization. Numerical simulations demonstrate the computational benefits and accuracy of the reduced-order model.
关键词： photovoltaic inverter,Maximum power point tracking,three-phase inverter,model reduction
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Distribution Feeder Fault Comparison Utilizing a Real-Time Power Hardware-in-the-Loop Approach for Photovoltaic System Applications
摘要： Power outages are a challenge that utility companies must face, with the potential to affect millions of customers and cost billions in damage. For this reason, there is a need for developing approaches that help understand the effects of fault conditions on the power grid. In distribution circuits with high renewable penetrations, the fault currents from DER equipment can impact coordinated protection scheme implementations so it is critical to accurately analyze fault contributions from DER systems. To do this, MATLAB/Simulink/RT-Labs was used to simulate the reduced-order distribution system and three different faults are applied at three different bus locations in the distribution system. The use of Real-Time (RT) Power Hardware-in-the-Loop (PHIL) simulations was also used to further improve the fidelity of the model. A comparison between OpenDSS simulation results and the Opal-RT experimental fault currents was conducted to determine the steady-state and dynamic accuracy of each method as well as the response of using simulated and hardware PV inverters. It was found that all methods were closely correlated in steady-state, but the transient response of the inverter was difficult to capture with a PV model and the physical device behavior could not be represented completely without incorporating it through PHIL.
关键词： faults,photovoltaic inverter,short-circuit analysis,hardware-in-the-loop
更新于2025-09-23 15:19:57
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A novel photovoltaic inverter topology based on common mode current suppression
摘要： Aiming at the problems of large leakage current and low efficiency of existing transformerless single-phase grid-connected photovoltaic inverters, a novel transformerless single-phase grid-connected photovoltaic inverter topology is proposed. In this topology, two freewheeling diodes are added to the single-phase full-bridge inverter, and the filter inductors are moved between the upper and lower bridge arms, so that the common mode voltage remains constant during the switching period and the common mode current is effectively suppressed. Meanwhile the high frequency switch uses MOSFET to reduce the switching loss, and the power frequency switch uses IGBT to reduce the conduction loss, and additional switches are avoided, thus the overall system losses are reduced. Finally, through simulation and the experimental platform of 3kW single-phase grid-connected photovoltaic inverter, it is verified that compared with the traditional full-bridge topology, the novel topology can effectively suppress the common mode current, while compared with the H5 and H6 topology, the novel topology reduces the system loss and improves the system efficiency.
关键词： efficiency,loss,single-phase grid-connected photovoltaic inverter,transformerless,common mode current
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE PES Innovative Smart Grid Technologies Conference - Latin America (ISGT Latin America) - Gramado, Brazil (2019.9.15-2019.9.18)] 2019 IEEE PES Innovative Smart Grid Technologies Conference - Latin America (ISGT Latin America) - Design of Common and Differential Mode Filters for Single-Phase Full-Bridge Photovoltaic Inverters
摘要： Photovoltaic arrays have high parasitic capacitance between positive/negative poles and earth. Therefore, conventional single-phase full bridge inverters with unipolar modulation are not suitable for applications in photovoltaic inverters because they have leakage currents higher than the limits acceptable by the standards. Additionally, high common mode currents tend to result in electromagnetic noise of significant magnitude. This paper proposes an integrated methodology for common and differential mode filter design for single phase full-bridge photovoltaic topology with a LCL filter. The differential mode filter is designed to meet the constraints of harmonic current distortion, while the common mode filter is designed to suit the ripple of common mode current and the filter quality factor to the design constraints. Simulation results show that the proposed methodology is simple and effective.
关键词： Photovoltaic inverter,Full-Bridge inverter,Differential mode filter,LCL filter,Common-mode filter
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Chengdu, China (2019.5.21-2019.5.24)] 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Modeling and Simulation of Virtual Synchronous Generator for Photovoltaic Inverter
摘要： The rise of photovoltaic installed capacity brings severe challenges to the safe and stable operation of the power grid. If the grid-connected inverter of the photovoltaic system can simulate the moment of inertia and frequency modulation characteristics of the synchronous generator according to external characteristics, the stability of the photovoltaic system can be improved. Therefore, the virtual synchronous generator control strategy (VSG) is proposed. This paper builds a generic simulation model of current source type photovoltaic inverter based on VSG technology, which can simulate a series of VSG behaviours including virtual inertia control, damping control, primary frequency control, reactive power control and fault ride through. The developed simulation model is also validated comparing to the actual PV power plant testing data, which shows accurate and reliable simulation results. The model of photovoltaic inverter can provide theoretical and model basis for the study of grid-connected stability and grid-connected operational characteristics.
关键词： VSG,photovoltaic inverter,Damping control,Droop control,Microgrid
更新于2025-09-16 10:30:52
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Small-Signal Modeling and Parameter Optimization Design for Photovoltaic Virtual Synchronous Generator
摘要： With the continuous proliferation of renewable energy generation, distributed photovoltaic inverters operating at a maximum power point reduce the inertia of power systems, degrading system frequency stability and potentially causing severe oscillations in systems after being disturbed. The virtual synchronous generator (VSG) control method, which causes photovoltaic inverters to possess inertia and damping, now plays an important role in the field of distributed generation. However, while introducing the advantages of synchronous machines, problems with oscillations are also introduced and the stochastic fluctuation characteristic of photovoltaics results in the stochastic drifting of the operating point. This paper presents an adaptive controller parameter design method for a photovoltaic-VSG (PV-VSG) integrated power system. Firstly, a small-signal model of the PV-VSG is built and a state space model is deduced. Then, the small-signal stability and low frequency oscillation characteristics of the photovoltaic power generation system are analyzed. Finally, considering the limitations of system oscillations and the stochastic drifting of the operating point, a global optimization design method for controller parameters used to improve system stability is proposed. The time domain simulation shows that an optimized PV-VSG could provide sufficient damping in the case of photovoltaic power output changes across a wider range.
关键词： optimal design of parameters,eigenvalue analysis,virtual synchronous generator,photovoltaic inverter,small-signal modeling
更新于2025-09-16 10:30:52
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Design and Implementation A Smart Monitoring and Controlling System of Three-Phase Photovoltaic Inverter Based on LoRa
摘要： In this paper, a new smart monitor and control system has been designed for injected power application to grid from a three-phase photovoltaic inverter (a smart monitor and control system (SMCS)). The system consists two main units. Firstly, the control system unit: this unit connects directly to the inverter to measure the output voltage of three-phase photovoltaic inverter and the control circuit, It can turn the inverter ‘on’ or ‘off’ from a long distance. Secondly, the monitoring unit: this unit is designed to monitor the states of the photovoltaic inverter system from long distances. It has two monitoring options OLED and a smartphone monitoring application. LoRa technique (long range) used to send and receive data between controllers system and monitoring system. LoRa is a new type of wireless communication technology within the Internet of Things (IoT). The SMCS application has been designed by using open source software “MIT App Inventor 2”; this application is used to sends and receives the data from a control unit by using Bluetooth as a wireless communication in order to monitor and control the whole system. The main advantage of the SMCS that it can monitor and control three-phase photovoltaic inverters that have been installed in remote and rural areas.
关键词： control system,IoT,smart monitoring,LoRa,photovoltaic inverter
更新于2025-09-12 10:27:22
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Study on nonlinear dynamic behavior and stable operation region of single-phase photovoltaic inverter
摘要： In order to design a photovoltaic inverter with excellent performance, the second-order photovoltaic inverter circuit model under current loop proportional control is established in this paper, the discrete iterative model of system is also obtained. The nonlinear behavior of system is analysed in detail through bifurcation diagram, folding diagram and the phase diagram of output current (i) and output voltage (uc). The simulation model is constructed in Matlab/Simulink, and the correctness of theoretical analysis is verified through time domain waveform and phase-space map. The influence of bifurcation and chaos on system spectrum is analysed from the frequency domain. According to the Jacobian matrix of system, the stable operation region of system is given. The experiment shows that the correct selection of circuit parameters is important for the stable operation of system.
关键词： nonlinear dynamic behavior,stable operation region,chaos,bifurcation,photovoltaic inverter
更新于2025-09-11 14:15:04