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.
The integration of Solar Photovoltaic (SPV) power generation system with the grid by using Enhanced Phase Locked Loop (EPLL) scheme based indirect control. The developed control scheme for synchronizing the SPV system with utility grid improves the power factor of the source and voltage profile at the point of common coupling (PCC). The proposed controller maintain the voltage profile at PCC through...
In this paper, a single-phase self-synchronized inverter with current limiting capability without a dedicated synchronization unit is presented. It offers an approach for power systems to control distributed renewable energy sources. The proposed system has the capability to synchronize itself with the utility grid before connection and track the grid frequency after connection without a phase-locked...
Grid-voltage synchronization algorithm performs the main role during unbalanced and distorted grid fault condition to measure the positive- and negative-sequence values of grid voltage at the point of common coupling for grid-tied renewable energy sources. Power control during severe grid conditions mostly depends on these measured values. Three-phase synchronous reference frame phase-locked loop...
This paper proposes a bi-directional grid-tied converter with GPS capability for smart-grid applications. The novelty of this converter is that time-stamped grid voltage angle received via network communication channels has been used to synchronize the converter to the grid. Therefore, all grid-tied converters in a microgrid with this development will not require line voltage sensing and phase-locked...
In this paper, control of a grid-tied converter as a voltage controlled converter is investigated for distribution level grids. Small signal model of the converter is presented and a control structure is designed to deliver desired active and reactive power. This controller is using power flow equations to control the converter as a synchronous machine and without the need for a dedicated synchronization...
In this paper, a single-phase self-synchronized inverter that mimics synchronous generators (Synchronverter) without a dedicated synchronization unit is investigated. It offers a mechanism for power systems to control distributed renewable energy sources. It can synchronize itself with the grid before connection and track the grid frequency very well after connection without a phase-locked loop (PLL)...
The increased trend in using the renewable energy instead of fossil fuel based generation due to its low environmental impact and to facilitate the increased consumption has led to extensive use of distributed generation. The use of power electronics with renewable energy offers wide advantages including greater controllability of generated power and fulfilling the requirements for grid connected...
The main contribution of this paper is to describe a robust Phase-Locked-Loop approach for three phase generation system with power flow control. This method, which is used to synchronize the inverter and the network voltages, is based on a comparison between the grid and the inverter angular positions, and correction of modulator period. The Solution presented in this paper is applied to the three...
A universal control method to operate the single phase inverters was proposed recently. The proposed method can operate the inverter regardless of whether it is connected to a stiff grid, to a weak grid, or to a load. Moreover, the transition between these modes of operation can be performed seamlessly. This feature makes the proposed method promising for smart microgrid applications where flexible...
This paper presents a grid-side model and control for small wind turbines connected to the grid using a back-to-back converter. The control is developed to transmit all power generated by an induction machine to the grid and to match grid requirements. The grid synchronization is achieved by a Double Synchronous Reference Frame Phase Locked Loop (DSRF-PLL) even during grid faults or unbalanced conditions...
Pushed by the booming installations of single-phase photovoltaic (PV) systems, the grid demands regarding the integration of PV systems are expected to be modified. Hence, the future PV systems should become more active with functionalities of low voltage ride-through (LVRT) and the grid support capability. The control methods, together with grid synchronization techniques, are responsible for the...
The Transmission System Operators are specially concerned about the Low Voltage Ride Through requirements of distributed generation power plants. Solutions based on the installation of STATCOMs and DVRs, as well as on advanced control functionalities for the existing power converters have contributed to enhance their response under faulty and distorted scenarios, and hence to fulfill these requirements...
A decentralized controller for the synchronization of two remote parallel voltage source inverters used to supply train auxiliaries is presented. A modular hybrid dynamic model of the entire power electronic apparatus is constructed; possible unbalanced line and load impedances are also considered. The power sharing between the converters is obtained by designing a droop controller based on local...
This paper investigates how different approaches to grid synchronization and reference frame orientation can improve the control performance of a voltage source inverter operating in a weak grid. It is first shown how voltage-sensor-less operation based on Virtual Flux allows for flexibility in how to choose the reference frame orientation of the control system. The different possible orientations...
In this paper a single phase inverter grid connected implementation is presented. The proposed solution is based on the calculation of the input line fundamental harmonic using a DSP processor. Our aim is to increase the inverter performance through a better synchronization with the grid and achieving a unitary power factor even in case of distorted input line, usually present in industrial environments...
This paper proposes a combined synchronization method for full scale converter of wind turbine (WT) aiming to ride trough balanced and unbalanced voltage dips due grid faults. A Kalman filter synchronization (KFS), capable extract the positive and negative sequence grid voltages, is designed to have a fast response to voltage disturbances. Then, a synchronous reference frame phase locked loop (SRF-PLL)...
Wind energy is nowadays widespread and the increasing number of wind turbine installations leads to more and more severe grid code requirements for grid connection. Control and grid synchronization algorithm must ensure these requirements on the whole range of operating mode, from starting to nominal power generation mode. In this paper, authors present reconfiguration control strategies, in order...
This paper presents a three-level three-phase neutral-point-clamped back-to-back converter applied to a wind emulator, where a wind power generator is connected to the grid through the back-to-back converter. The converter regulates the power extracted from the generator and controls how this power is injected to the grid with the desired power factor. Two phase locked loops are in charge of synchronizing...
This paper presents a new harmonic currents identification method called neural synchronous method and based on artificial neural networks. Its theoretical aspect relies on a new decomposition of the load current signals. Adaline neural networks are used in order to learn this decomposition on-line; the fundamental currents can therefore be estimated at each sampling time. The fundamental currents...
This paper offers an overview of the passive methods used for islanding detection. A monitoring PLL has been adopted for the estimation of the voltage amplitude and frequency. Passive inverter resident methods discussed are the over/under voltage (OUV), over/under frequency (OUF), the voltage harmonic monitoring (with a study on the effects of the grid impedance value and of the inverter DC voltage...
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.