The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Grid-connected inverter is an important part of the grid-connected system. Compared with the traditional L or LC filter, LCL filter has a better high-frequency harmonic attenuation performance. However, LCL filter has resonant peak, which has a great influence on the stability of the system. This paper first analyzes the effect of passive damping method on the resonance peak; then a double closed-loop...
Since the capacitor equivalent series resistance (ESR) above 1kHz almost stays constant, dc-link current root-mean-square (RMS) closed form equation is an easy way to evaluate the capacitor losses from the switching harmonic currents (SHCs). But when the ac current contains multiple low order harmonics (LOHs), their impacts on the dc-link has not been systematically studied. In this paper, a straightforward...
Nowadays capacity of the photovoltaic systems in the grid is remarkable and provides a major part of energy in the grid. Therefore, an abruption of these systems from the grid can create a damage to the grid. Unlike in the past that PV systems disconnected from the grid when a voltage drop occurred, nowadays these systems should have Low Voltage Ride-Through (LVRT) capability. The PV system should...
This paper presents an approach for upgrading droop control aimed to improve its performance when used for two parallel inverters. The proposed control ensures equal voltage for the two inverters when different power flowing through them which guarantee zero current circulation. To fulfill the voltage regulation, the second inverter (slave) regulates its voltage to follow the master inverter reference...
Due to the high-scale penetration of single-phase photovoltaic (PV) systems in distributed generation, a single-stage single-phase grid-connected PV system, with a nonlinear control strategy is presented in this paper. Using the general structure for synchronous dq0 frame, the controller is developed to obtain maximum power from the PV array regardless of the atmospheric conditions without the requirement...
In this work, three-phase single stage grid-connected photovoltaic system using current control inverter is simulated using Matlab/Simulink. To deal with varying irradiance conditions, the incremental conductance MPPT has been used, however in order to improve the power quality a three-level (NPC) inverter based SVM control together with LCL filter has been used. The main result of the project is...
The paper addresses the problem of fault detection in an unbalanced microgrid with distributed generators, using algorithms based on harmonic estimation: Wavelet Transform (WT), Fast Fourier Transform (FFT) and Reduced Fast Fourier Transform (RFFT). Simulations were carried out in the MATLAB/SimPowerSystems environment. Modified IEEE13 bus system with distributed generation was used. Experimental...
In this work, a Lyapunov-function based control method for three-phase grid-tied LCL-filtered quasi-z-source source inverters (qZSIs) is proposed. The mathematical model of grid-tied qZSI is modeled in the synchronously rotating dq-frame. Motivated from the energy distribution in qZSI, an energylike function (referred to as Lyapunov-function) is formed. Then, using Lyapunov's direct method a Lyapunov-function...
This paper presents the mathematical model of a three phase Solid State Transformer (SST). The model is designed in PLECS. The model is integrated into a grid with high penetration of non-linear loads. The model addresses constraints including smooth voltage regulation, permitted Total Harmonic Distortion and the incorporation of distributed generation and energy storage. The main feature of the SST...
In order to suppress harmonics and optimize power grid quality for the indirect matrix converter (IMC), harmonic characteristics of the input current in IMC are analyzed. The classic dual space vector modulation (SVM) method is adopted for IMC. Generally, only the rough results of harmonic analysis can be achieved by using the conventional mathematical model based on the transfer function. In this...
Various topologies of multilevel inverters have been proposed as a potential replacement for cascaded multilevel inverters in high-voltage, high-power applications as they can be extended to any number of voltage levels without introducing much more complexity to the control system. This paper discussed in detail about the application of selective harmonic elimination pulse-width modulation (SHE-PWM)...
This paper proposes the quasi-proportional resonant (QPR) fuzzy control of the LCL-type grid-connected inverter, which is based on 1) the inner-loop feedback control of the capacitor current and 2) the outer-loop QPR control of the grid-side current. Also, in the controller, self-tuning of the fuzzy parameters is used in regulating the parameters of QPR controller. The advantages of our methods are...
This paper introduces a MATLAB simulation of 3 phase grid tied inverter which synchronizes with grid as per grid requirement. The aim of this simulation is an implementation of the designed filter to effectively reduce the ripple component injected into the grid to an acceptable value. The focus is on designing inverter which will synchronize with grid. The design and analysis of the grid synchronization...
Dynamic Voltage Restorer (DVR), which has being considered to be one of the most cost-effective solutions to protect sensitive loads from voltage distortions, yet may be degraded in its compensation performance due to the poor response characteristic of the normally single-stage LC filter especially in situations of e.g. distorted load current. This paper proposes a structure of DVR characterized...
This paper presents a comparative analysis of Voltage Source Inverter using Sinusoidal Pulse Width Modulation Method and Third Harmonic Injection Pulse Width Modulation Method in Three level inverter for different loads with LC filter. In this paper designed the Simulink model of Inverter and Induction motor. All above technique is used to reduce the Total Harmonic Distortion (THD) or the power quality...
Ideally, distribution utilities are responsible to provide good power at a fixed rated frequency to the consumer end at unity power factor. Due to the bulk usage of non-linear power electronic loads, distribution system network (DSN) suffers large current distortion. Further, the intermittent hybrid natural green sources (HNGS) like PV and PMSG wind grid connected using hysteresis current controller...
This paper proposes a cascade voltage/current control method (vector control) for a three-phase inverter for grid connected applications. The study mainly focuses on the innovative control law based on the flatness properties for a three-phase inverter with output LC filter. Utilizing the flatness principle, we propose simple solutions to the control and stabilization problems. The effectiveness of...
Delivering quality power is the important issue of grid connected solar photovoltaic (PV) system. The generation of quality power from the proposed system is influenced by the intermittent nature of solar photovoltaic power, power electronic converters used and the nonlinear loads connected to the system. To understand and analyze the system an accurate modeling is required. This paper deals with...
This paper presents the decoupled active and reactive power control (PQ control), using a Phase-Locked Loop (PLL) for synchronization, and applied to the control of Multicellular Parallel Inverter (MPI) for a grid-connected Photovoltaic (PV) system. We explain the value of this multicellular structure of inverter compared to a conventional inverter. We also present and discuss the simulation results...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.