- 标题
- 摘要
- 关键词
- 实验方案
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Improved three-vector based dead-beat model predictive direct power control strategy for grid-connected inverters
摘要： Since only one inverter voltage vector is applied during each duty cycle, traditional model predictive direct power control (MPDPC) for grid-connected inverters (GCIs) results in serious harmonics in current and power. Moreover, a high sampling frequency is needed to ensure satisfactory steady-state performance, which is contradictory to its long execution time due to the iterative prediction calculations. To solve these problems, a novel dead-beat MPDPC strategy is proposed, using two active inverter voltage vectors and one zero inverter voltage vector during each duty cycle. Adoption of three inverter vectors ensures a constant switching frequency. Thus, smooth steady-state performance of both current and power can be obtained. Unlike the traditional three-vector based MPDPC strategy, the proposed three vectors are selected based on the power errors rather than the sector where the grid voltage vector is located, which ensures that the duration times of the selected vectors are positive all the time. Iterative calculations of the cost function in traditional predictive control are also removed, which makes the proposed strategy easy to implement on digital signal processors (DSPs) for industrial applications. Results of experiments based on a 1 kW inverter setup validate the feasibility of the proposed three-vector based dead-beat MPDPC strategy.
关键词： Grid-connected inverter,Model predictive control,Constant switching frequency,Power errors,Direct power control,Three vectors
更新于2025-09-23 15:23:52
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[IEEE 2020 11th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC) - Tehran, Iran (2020.2.4-2020.2.6)] 2020 11th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC) - Utilization of Soft-Switched Boost Converter for MPPT Application in Photovoltaic Single-Phase Grid-Connected Inverter
摘要： A modified soft-switched boost converter with a lower number of auxiliary components is proposed in this paper that provides either zero-voltage-transition (ZVT) or zero-current-transition (ZCT) operation for main switch and diode. Proposed converter is utilized in a single-phase grid-tied photovoltaic power generation system. Due to importance of maximum power harvesting from PV, incremental conductance MPPT procedure is employed to control DC/DC converter. Simulation is performed in PLECS software to validate the advantageous introduced soft-switching technique.
关键词： Zero-Voltage-Transition (ZVT),Zero-Current-Transition (ZCT),Single-Phase Grid-Connected Inverter,Incremental Conductance MPPT,Soft Switching Boost Converter
更新于2025-09-23 15:21:01
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Robust Model Predictive Control (MPC) for large-scale PV plant based on paralleled three-phase inverters
摘要： In this contribution a robust Model Predictive Control (MPC) is proposed to enhance the power quality of a large-scale PV plant connected to the grid through Paralleled Voltage Source Inverters (PVSIs) with common AC and DC buses. Paralleling inverters allow handling high-power export and offer advantages in terms of redundancy which ensure the system reliability. However, due to the physical differences and parameter disparities between the inverters, zero sequence circulating currents will flow through it, which will disturb the performance of the system. Hence, the control goal is to regulate the currents injected into the grid, suppress the zero-sequence circulating current (ZSCC). Consequently, this study proposes an MPC algorithm that is based on optimization approach which allows minimizing circulating currents. In order to show its effectiveness and performance of the proposed control, a comparison with linear PI controller is included. In addition, design control and tuning procedure are detailed. Simulation results show the performance of the proposed controller in ensuring power quality, and suppressing circulating currents. To verify the real-time feasibility of the proposed control scheme, Hardware-In-the-Loop (HIL) setup is carried out with means of Opal-RT and dSPACE rapid prototyping systems.
关键词： Hardware-in-the-loop,Model predictive control,PV power plant,Grid-connected inverter,Circulating current,Parallel operation
更新于2025-09-23 15:21:01
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[IEEE 2019 8th International Conference on Renewable Energy Research and Applications (ICRERA) - Brasov, Romania (2019.11.3-2019.11.6)] 2019 8th International Conference on Renewable Energy Research and Applications (ICRERA) - The Closed Loop Controller Gain Characterization for Enhanced Current Quality in Solar Inverters Coupled with Weak Grid
摘要： Majority of solar installations are coming up in remote locations where the stiffness of the grid is very weak, enforces to connect solar inverters to weak grid. In weak grid scenario, solar inverter would inject harmonic current into the grid that affect the power quality of the system. The solar inverters are designed to operate with stiff grid in which the closed (feedback and feed forward) loop control is planned by considering absolute decoupling between the direct and quadrature grid injected current. With the conventional design speci?cations in weak grid scenario, the absolute decoupling between the direct and quadrature current cannot be achieved due to grid inductance. The improper decoupling would create the oscillations in the grid injected current that result in increased harmonic distortion. To compensate the current oscillations, the current controller feedback loop gain need to be designed by accessing the degree of coupling. Since the grid injected current sensed at the point of common coupling and transformed to DC quantities (direct current id and quadrature current iq) using synchronous angle, the same current oscillations appear in d-axis and q-axis current control loop. In this work, the d-axis and q-axis loop oscillations with respect to grid inductance are analyzed analytically. Based on the analysis the d-axis and q-axis PI controllers are designed independently unlike conventional PI controller to ensure not only faster dynamic response of the system but also improved power quality.
关键词： closed loop control,weak grid,PI controllers,current THD,Grid connected solar inverter,single stage transformer less grid connected inverter,Power quality
更新于2025-09-23 15:19:57
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Performance analysis of the Single-Phase Grid-Connected Inverter of a photovoltaic system in water and wind applications
摘要： Single-phase grid connected inverters are nowadays broadly developed and tested in various types of applications especially in photovoltaic systems. The main aim of the inverter control strategy is to extract the maximum energy from the PV system which corresponds to the maximum power at certain conditions. However, the MPPT methods are also important in other renewable energy conversion systems. This paper analyses the performance of a commercially available photovoltaic inverter in water and wind systems. Presented models are implemented in a laboratory test bench in the form of torque characteristics realised by an induction motor fed by the inverter with vector control. The parameters are scaled into relative variables to provide a proper performance comparison. Presented tests include step response to assess the performance of a system dynamic. The dynamic tests showed a fast response of the investigated systems. The MPPT tracking accuracy tested under realistic profiles is similar for both cases: 98% and 96% respectively for the wind and water systems. These results prove the satisfactory performance of the MPPT of the PV microinverter in these applications.
关键词： Single-phase grid-connected inverter,wind turbine,water turbine,MPPT,photovoltaic system
更新于2025-09-23 15:19:57
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[IEEE 2019 Chinese Automation Congress (CAC) - Hangzhou, China (2019.11.22-2019.11.24)] 2019 Chinese Automation Congress (CAC) - Research on Reactive Power Optimization Control Strategy of Distribution Network with Photovoltaic Generation
摘要： What the thesis studies is the active and reactive decoupling control method of photovoltaic grid-connected inverter, and then the reactive power of grid-connected inverter is optimized by genetic algorithm with the objective of minimizing network loss, So as to realize reactive power optimization control of the photovoltaic power generation system.An algorithm based on genetic algorithm for reactive power optimization of photovoltaic power generation and distribution network is proposed.A mathematical model for reactive power optimization of distribution network has been established. The mathematical model those of photovoltaic power generation system Considering the limits of not only minimum network loss but also node voltage, what is used to optimize the reactive power of photovoltaic power generation is genetic algorithm. The example simulation results indicate the designed optimization algorithm is effective and correct in reducing power loss and improving voltage quality.
关键词： Photovoltaic power generation,Grid-connected inverter,Genetic algorithm,Reactive power optimization
更新于2025-09-19 17:13:59
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Single-phase photovoltaic grid-connected inverter for predictive control method with power feed-forward
摘要： In the traditional photovoltaic grid-connected inverter control, there are problems such as slow system response speed, low stability and grid-connected current distortion. In this regard, a novel current prediction control method for grid-connected inverter with power feed-forward is proposed. The method consists of DC voltage outer loop control, current predictive control, power feed-forward and grid voltage feed-forward. The characteristic is that the current prediction control algorithm derived from the state equation of the grid-connected inverter effectively suppresses the influence of DC voltage fluctuation on the grid-connected current and enhances the robustness of the system; the introduction of power feed-forward accelerates the dynamic response of the system; The introduction of grid voltage feed-forward reduces voltage distortion or current distortion. And the traditional PI control module is not needed, the structure is simple, and the circuit is easy to implement. Matlab/Simulink simulation model and experimental results prove the effectiveness of the proposed control method, which is more practical than the traditional double loop control method.
关键词： predictive control,power feed-forward,photovoltaic grid-connected inverter,grid voltage feed-forward,current prediction control
更新于2025-09-16 10:30:52
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Resonance Instability of Photovoltaic E-Bike Charging Stations: Control Parameters Analysis, Modeling and Experiment
摘要： This article presents an in-situ comparative analysis and power quality tests of a newly developed photovoltaic charging system for e-bikes. The various control methods of the inverter are modeled and a single-phase grid-connected inverter is tested under different conditions. Models are constituted for two current control methods; the proportional resonance and the synchronous rotating frames. In order to determine the influence of the control parameters, the system is analyzed analytically in the time domain as well as in the frequency domain by simulation. The tests indicated the resonance instability of the photovoltaic inverter. The passivity impedance-based stability criterion is applied in order to analyze the phenomenon of resonance instability. In conclusion, the phase-locked loop (PLL) bandwidth and control parameters of the current loop have a major effect on the output admittance of the inverter, which should be adjusted to make the system stable.
关键词： grid-connected inverter,photovoltaic,solar mobility,resonance instability,power quality,solar charging
更新于2025-09-16 10:30:52
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A Zero-Voltage-Transition H5-Type Transformerless Photovoltaic Grid-Connected Inverter
摘要： Efficiency and leakage current are two major issues for transformerless grid-connected inverters (TLI). Soft-switching technologies can reduce switching losses and be applied in TLIs. Herein, a zero-voltage-transition H5 type (ZVT-H5) inverter with soft turn-on and turn-off transitions of high-frequency main switches is derived from basic resonant tanks. Compared with the hard-switching H5 (HS-H5) inverter, the conversion efficiency of ZVT-H5 is significantly improved. Moreover, the reverse recovery problem of freewheeling diodes is alleviated under the operation of the auxiliary resonant network. Meanwhile, a diode clamping branch is employed to achieve constant common-mode characteristic for the ZVT-H5. The construction process of the proposed topology is described, and the operation principle of the auxiliary resonant network is analyzed. Moreover, the resonant parameter design of ZVT-H5 and its circuit performance are discussed in detail. Finally, the experimental results of a 3-kW prototype at 100 kHz switching frequency are provided to verify the effectiveness of the ZVT-H5.
关键词： Grid-connected inverter,Resonant tank,Transformerless,Zero-voltage-transition (ZVT)
更新于2025-09-16 10:30:52
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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) - Control and Modulation Method of a Three-phase Eight-switch Inverter for Two-stage Grid-connected Photovoltaic Systems
摘要： A novel transformerless two-stage photovoltaic (PV) grid-connected inverter is introduced in this paper. The system is composed of three-level boost (TL-Boost) DC/DC circuit and three-phase T-type eight-switch DC/AC topology. By using the multiloop interleaved control strategy and adjusting the conduction time of power switch phase of the first-stage boost DC/DC part, the inductor current ripple is reduced and the balance of DC bus capacitor voltage could be achieved respectively. Meanwhile, a nine-vector space vector pulse width modulation (SVPWM) algorithm based on optimal five-stage is adopted for eight-switch DC/AC inverter circuit, which could simplify the algebraic operation, reduce the switching loss and improve the utilization of the DC bus voltage. Finally, a 10kW experimental platform is built to verify the validity and effectiveness of the proposed control and modulation method.
关键词： TL-Boost,T-type eight-switch,nine-vector SVPWM,PV grid-connected inverter,multiloop interleaved control
更新于2025-09-12 10:27:22