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.
Multilevel inverters as the best existing solution for high power/ medium voltage applications have been utilized to incorporate renewable energy sources into electric grid. Solar energy, and fuel-cells as two major sources of power can only provide unidirectional power flow. However, utilizing cascaded H-bridge inverters or other inverters with trinary voltage ratios at the input DC links might cause...
In off-grid renewable power systems, batteries are often used to balance the mismatch between load and electricity generation. The mismatch may be more severe in small-scale systems due to the lack of averaging effect seen in larger power systems. In the former, batteries have to cope with rapid power fluctuations whilst still delivering power to consumers. A vanadium redox flow battery (VRB) may...
Conventional Hybrid Power Quality Conditioner (HPQC) adopts LC coupling branch and L coupling branch in the back-to-back converters to reduce the converter compensation capacity as well as the DC voltage. However, HPQC could only achieve the minimum compensation capacity under certain special load condition. To maintain the converter compensation capacity at a low level under all load conditions,...
The virtual inertia J in single-phase synchronverter (SPSV) can be designed specifically to improve system stability. However, J also relates to active power loop (APL) and reactive power loop (RPL) time constants, which restricts the flexibility of control parameters choice and increases the complexity of parameter design process. This paper proposes a method to increase SPSV overall inertia without...
A good methodology flow can improve significantly the time needed to develop an I/O library. It is mandatory that the fastest methodology also gives accurate results. Given the new technology nodes, it is important to re-evaluate all the software characterization formats (NLDM, CCS and ECSM) and see if there is room for improvement. The analysis will be conducted by comparing liberty file data with...
Silicon carbide (SiC) MOSFETs have been widely studied in high frequency applications. The switching performance, however, is limited with the existence of the parasitic elements. One critical issue is the susceptibility of the gate-source voltage to the parasitic elements, rendering the possibility of spurious operation of the SiC MOSFETs. This paper conducts comprehensive investigations on the impact...
This paper presents comprehensive validation tests of a recent qd0-frame core-loss model of three-phase induction machines at different load conditions. The machine is run at different frequencies/speeds and flux levels. These tests reinforce the model at different operating conditions before further model-based analysis and control design. Moreover, to properly use the model, a series of model parameter...
Wireless charging for electric vehicles is gaining more and more popularity recently. This paper analyzes the wireless power transfer (WPT) system with a constant-voltage source and a constant-current load, which is featured in series compensation in the transmitter and parallel compensation in the receiver. The source voltage and the load current are square waves with fixed amplitudes. The closed-form...
ESN load forecasting model has high stability, and is able to learn fast and not easy to fall into local optimum, compared with standard recurrent neural network. In the process of constructing the typical ESN model, the choice of parameters is always empirical or random. The forecasting performance of ESN was analyzed on the basis of its key parameters. While the dynamic reserve pool has black box...
A mechatronic system results form the integration of several components from different domains. The system's behavior is sensitive to the values of its parameters and variables. Be it small or large, a variation in these values can significantly influence the overall functioning of the system. To provide a high quality product, the fluctuations between actual and target values of parameters should...
We present a feasibility analysis of the controlled delivery power grid (CDG) that uses aggregated power request by users to reduce communications overhead. The CDG, as an approach to the power grid, uses a data network to communicate requests and grants of power in the distribution of electrical power. These requests and grants allow the energy supplier know the power demand in advance and to designate...
This paper introduces the unified equivalent circuit model for modular high voltage(HV) power generation architectures. The HV generation architectures are introduced considering the modularity of key HV components such as transformers or rectifier circuits firstly. An equivalent resister and capacitor circuit network is adopted to model the HV transformer and multi-stage voltage multiplier circuit...
Three-phase/level T-type converter has advantages of high efficiency and low current harmonics, which is utilized in power conversion systems for supplying dc loads widely. Three-phase/level T-type converter provides bipolar dc buses with a neutral line at relatively low cost. In order to extend applications for bipolar dc bus structure, voltage independence control of split-dc bus proposed in this...
E-commerce marketplaces are highly dynamic with constant competition. While this competition is challenging for many merchants, it also provides plenty of opportunities, e.g., by allowing them to automatically adjust prices in order to react to changing market situations. For practitioners however, testing automated pricing strategies is time-consuming and potentially hazardously when done in production...
The increasing number, complexity, and variability of business rules in today's enterprises introduces the need for their effective and flexible management. In several research fields, such as the semantic web, library science, and data tailoring, effective organization of knowledge is enabled by contexts. We previously proposed a static structure model for context-based business rule management....
Due to different initial state of charge (SOC) of energy storage system, the SOC of cascaded storage module is unbalanced in microgrid. Many conventional methods realize SOC balance of cascaded storage module based on centralized communication. In this paper, a decentralized SOC balancing method is proposed without any communication. In this scheme, the modified P-f curves are changed by the local...
Solid state transformers (SSTs) include dc subsystems to enable plug-and-play support of dc loads, generation sources, and energy storage. Dual active bridge (DAB) converters are a suitable topology for both the primary energy conversion and load interface applications in an SST. This study considers an SST that uses DAB converters for both applications, and describes a method of generating a full...
This work presents a new Finite Control Set Model Predictive Control (FCS-MPC) strategy based on an input reference tracking. The control structure admits a closed-loop representation featuring a linear dynamic and a perturbation term. Thus, the stability and the design process can be carried out by means of standard control methods. Besides, it reduces the computational burden because the minimization...
The difficulty of modeling a resonant converter is the fact that, unlike a pulse-width-modulation (PWM) converter, an average concept doesn't work. The only successful equivalent circuit model, proposed by E. Yang, is based on fundamental approximation and harmonic balance theory. However, it is conceptually hard to understand because of an unidentified “equilibrium state.” A resonant converter was...
This paper investigates the fault ride-through (FRT) capability of a hybrid AC/DC microgrid during both AC and DC network faults. In this investigation, commonly proposed FRT strategies for the distributed energy resources and AC and DC microgrids are implemented while the interlinking bidirectional converter is operated in power transfer mode. The investigations have shown that improvement in the...
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.