Design and Control of DC–DC Converters in a PV-Based LVDC Microgrid
The primary concerns in designing and control of LVDC microgrid involve: (a) choice of suitable converter, (b) extraction of maximum power from RES, (c) voltage regulation and (d) power sharing among various sources and loads [7, 8]. The output power of PV is intermittent in nature and is affected due to change in climatic conditions.
Residual-based Short-Circuit fault detection and isolation in LVDC
"Static-Dynamic Analysis of an LVDC Smart Microgrid for a Saharian-Isolated Areas Using ETAP/MATLAB Software", in Smart Energy Empowerment in Smart and Resilient Cities. Cham (2020), pp. 496-505, 10.1007/978-3-030-37207-1_53. View in
MPC-based control for a stand-alone LVDC microgrid for rural
The considered stand-alone DC microgrid and corresponding control structure is presented in Section 2, with details on system topology, loads, and PV and ESS selection and sizing.Section 3 reports: (a) the models used for system simulations, (b) the MPC control design, including model selection and optimization problem formulation, and (c) the definition of
An optimal configuration method of DC reactor in LVDC microgrid
Short-circuit fault has a great impact on the safety of LVDC microgrids. In order to avoid damage to the DC equipment within microgrid, DC reactors need to be deployed to limit the fault current. This paper proposes an optimal configuration scheme of reactors based on the analytical solution of fault current. Firstly, the equivalent models of the different converters in
Protection of low voltage DC microgrids: A review
Another fault location technique for an LVDC microgrid PPU is presented in [106]. Unlike the approach in [105], it uses an attenuation constant of the damped probe current response. Faults close to the PPU are detected with the help of external resistance and inductance, which corresponds to about 0.5 km length of the cable. The fault distance
Selection of LVDC Microgrid Component for Efficient Microgrid
The LVDC distribution has piqued academic interest due to expansion in power electronics technologies. The use of converters, however, has created many technical problems for their protection and control in the case of a failure under improper circumstances. In converter-fed systems, after-the-fault conduct LVDC distribution protection is much different and more
Control Architectures for Low Voltage DC (LVDC) Microgrid
The DC MG Control techniques promise that the control will be improved, steady, and efficient. The PE converters act as an interface between the grid and the load which may provide proper control to the microgrid with modified voltage regulation, and better distribution of current (Zhang et al. 2016).This interface may simplify the connections of
LVDC Microgrid Perspective For A High Efficiency Distribution System
A survey on the alternative DG units'' configurations in the low voltage AC (LVAC) and DC (LVDC) distribution networks with several applications of microgrid systems in the viewpoint of the current
ESTIMATION OF SHORT CIRCUIT CURRENTS IN FUTURE
LVDC MICROGRID WITH ENERGY SOURCES AND LOADS The energy sources that are considered in this study are photovoltaic (PV), energy storage system (ESS) and connection with the MVAC/MVDC network. Fig. 2: LVDC network with energy sources and DC loads Connection to MV Grid Connection of LVDC microgrid to a MV network can be either AC or DC.
Ground Fault Detection Using Hybrid Method in IT System LVDC Microgrid
Low voltage direct current (LVDC) microgrid systems have many advantages over low voltage alternating current (LVAC) systems. Furthermore, LVDC microgrids are growing in use because they are easy to link to distributed energy resources (DER) and energy storage systems (ESS), etc. Currently, IT system LVDC microgrids are widely used in direct current
LVDC Microgrid Perspective For A High Efficiency
A survey on the alternative DG units'' configurations in the low voltage AC (LVAC) and DC (LVDC) distribution networks with several applications of microgrid systems in the viewpoint of the current
Power System Inertia Enhancement Based on LVDC Microgrids
5 天之前· There is a critical need to increase power system inertia during the grid transformation. However, in a low-voltage dc (LVDC) microgrid, many potential inertia contributors, such as
Energy management scheme in microgrid with LVDC using smart
A new energy management scheme for grid-integrated battery-based solar PV system is developed for a more practical DC bus voltage of 48 V. The main objective of the proposed work is to feed the grid by optimizing the available energy from PV and battery system. A unique advance adaptive control algorithm is used to generate the reference signal which is
Protection of LVDC Microgrids in Grid-Connected and Islanded
Low-voltage dc (LVdc) microgrids facilitate the integration of renewable energy systems and modern loads. However, they suffer from the lack of a sensitive, selective, reliable, and fast protection strategy. The low fault current of high-resistance faults makes fault detection and faulty zone identification challenging tasks for protection engineers. This article proposes
IEEE TRANSACTIONS ON POWER ELECTRONICS Current
illustrated in Fig. 1. For example, LVDC microgrids can efficiently deliver high-quality power independent from the utility to the end-user with battery energy storage system or s [12] -[13]. A solid state DC transformer (DCT) can conveniently interconnect such LVDC microgrids and MVDC grids [14]-[15]. In another example of solar farms,
Selection of LVDC Microgrid Component for Efficient Microgrid
This paper examines the ultra- modern safety mechanisms set up for DC microgrid, with a focal point on LVDC Control strategy, construction, load flow, and strength management. Published
Product note Fault protection of LVDC microgrids
Figure 2 – DC short circuit current components in an active LVDC microgrid Figure 3 – DC positive pole ground fault current path in an active LVDC microgrid with the neutral point of the MV/LV transformer grounded even if the DC generators contribution may be switched off by IGBT block. It must be pointed out that ground faults are
Technical Application Papers No.14 Faults in LVDC
4 Faults in LVDC microgrids with front-end converters Introduction Figure I.3 – DC positive pole ground fault current path in an active LVDC microgrid with the neutral point of the MV/LV transformer grounded Figure I.2 – DC short circuit current components in an active LVDC microgrid If, on the other hand, the fault is on the DC side, fault
Current-Source Solid-State DC Transformer Integrating LVDC
This paper proposes current-source DC solid-state transformer (SST) for MVDC collection system in WT, PV, and ES farms or as an interface between the MVDC grid and the LVDC microgrid.
Fault control and line protection strategy for LVDC microgrids
The essence of line protection in LVDC microgrids includes: (1) using additional thyristors in the modified DCSST to avoid the high current flowing through the freewheeling diodes; (2) lowering the critical requirements for fast fault identification and isolation by coordinating the converter control and line protection; (3) tripping the
An improved decentralized control strategy for a PV hybrid energy
The existing DC/DC converters used in an LVDC microgrid have a common drawback: the conventional Buck or boost circuit topology severely limits the input voltage range, which can constrain the design of the distributed PV or HESS modules. However, the voltage of the distributed PV or HESS modules varies over a wide range, and a single Buck or
Deep neural network enabled fault detection in LVDC
A small-scale ring-type LVDC microgrid simulation and hardware implementation are planned and evolved to conduct the recommended study. DC system current and the voltage signal are measured under usual and fault conditions to examine the fault characteristics. The convolutional neural network
Analysis of LVDC Microgrid Protection Requirements and
In the low voltage (LV) distribution network, DC microgrid has been widely considered for its convenient and efficient absorption of new energy. With the multi-terminal access of photovoltaic, energy storage and other distributed energy sources, the fault characteristics of DC microgrid become more complex, which also puts forward higher requirements for protection.Based on
Mikko Heinonen COMPARISON OF LVAC AND LVDC
3 LVAC AND LVDC MICROGRIDS 15 3.1 LVAC MG advantages and disadvantages 15 3.2 LVDC MG advantages and disadvantages 16 3.3 Energy efficiency and savings of LVDC technology compared to LVAC technology in microgrids according to literature 18 3.3.1 Power electronics and power conversion 19
LVDC Microgrids for Power Sharing in Energy Community
The scheme of this architecture is depicted in Fig.1 2) Low Voltage DC (LVDC) microgrid: in this case, the renewable energy source output converter is a Buck-Boost dc/dc and the bus connecting
Liran ZHENG | Doctor of Philosophy | Georgia Institute
Solid-state DC transformer to integrate low-voltage DC (LVDC) microgrid, wind turbine (WT) generator, photovoltaic (PV), and energy storage (ES) into medium-voltage (MV) direct-current (MVDC
Microgrid Answers via Georgia Tech Project
A partnership between the Georgia Institute of Technology and Georgia Power, a Southern Company utility, aims to study "all the questions you can ask about a microgrid" through the 1.4-MW Tech Square Microgrid, a