Repository logo
 

Faculty of Engineering and Built Environment

Permanent URI for this communityhttp://ir-dev.dut.ac.za/handle/10321/9

Browse

Author: search.filters.author.Davidson, Innocent E.Subject: search.filters.subject.Inverter

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Decentralized fast delayed signal cancelation secondary control for low voltage ride-through application in grid supporting grid feeding microgrid
    (Frontiers Media SA, 2021-04-15) Buraimoh, Elutunji; Davidson, Innocent E.; Martinez-Rodrigo, Fernando
    In this study, a distributed secondary control is proposed alongside the conventional primary control to form a hierarchical control scheme for the Low Voltage Ride-Through (LVRT) control and applications in the inverter-based microgrid. The secondary control utilizes a fast Delayed Signal Cancelation (DSC) algorithm for the secondary control loop to control the reactive and active power reference by controlling the sequences generated. The microgrid consists of four Distributed Energy Resources (DER) sources interfaced to the grid through interfacing inverters coordinated by droop for effective power-sharing according to capacities. The droop also allows for grid supporting application for microgrid’s participation in frequency and voltage regulation in the main grid. The proposed decentralized fast DSC performance is evaluated with centralized secondary and traditional primary control using OPAL-RT Lab computation and MATLAB/SIMULINK graphical user interface for offline simulations and real-time digital simulator verification. This study presents and discusses the results.
  • Thumbnail Image
    Item
    Modeling and assessment of the fault ride-through capabilities of grid supporting inverter-based microgrids
    (IEEE, 2020-03) Buraimoh, Elutunji; Davidson, Innocent E.
    Grid-connected micro-grids are subject to grid disturbances. This has undesirable effects on system operation. Riding through fault conditions is a crucial technical challenge. Evolving grid codes require micro-grids to possess fault ridethrough capabilities and support the grid voltage recovery to imitate the behavior of the traditional electrical power systems. The paper proposes two models of a grid supporting inverterbased microgrid; the first controlled as a current source with a parallel impedance suitable for grid feeding applications; the second regulated as a voltage source with a virtual impedance suitable for grid forming applications. The main objective of these two systems is to achieve controlled power delivery to the grid using grid voltage and frequency regulation. This paper discusses power interaction under steady states and transient conditions. Grid voltage parameters, such as amplitude, phase angle, and frequency, are estimated using a synchronization system, as these are necessary for precise active and reactive power control. Results obtained provide an understanding of grid fault impact on grid supporting systems and fault ridethrough compliance and evaluates the impacts of the virtual impedances on fault ride through and power interaction.