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.
Lately, new solutions have been added to the control of autonomous grids, which improve the way the power grids operate. These changes may affect the reliability and safety of power distribution grids, the dynamic stability being a real concern. This issue is more prominent in autonomous microgrids (MGs) with high penetration of renewable energy sources. On this topic, this paper aims to study how...
In this paper we propose a methodology for reliability evaluation, failure prediction, and failure mitigation of a STT-MRAM memory under different supply voltage conditions (i.e., DVS scenarios). The methodology is based on the design of read/write failure predictor registers which are able to predict the memory failure probability for a given DVS scenario. The predicted results are used to re-tune...
For the proper functioning of a society it is imperative that a strategic and important objective like the security of the energy system is to be considered. Technological advancements in the power sector, like the integration of information and communication technology, determine cyber security vulnerabilities. In this paper, we discuss the impact of cyber-attacks over the stability of the power...
The modular multilevel converters (MMCs) are composed of many sub-modules(SMs) connected in series. Module control unit is key components of the SMs, and a auxiliary power supply is needed to energize the module control unit. However, Many MMCs projects require the voltage of IGBT to be higher than 3300V, which means the input voltage of auxiliary power supply used in MMCs should be higher than 2500V...
This paper focuses on improving the dynamic behaviour of a microgrid (MG) supplied by a self-excited induction generator (SEIG) when feeding mainly induction motors (IMs) of significant power. In order to sustain the MG during the transitory regime induced by the IMs connection, a short-term energy storage system based on a supercapacitor (SC) is added to the MG control system. Also, a stepped capacitor...
This paper presents a filter-based control scheme for an H-Bridge inverter with output LC filter. This approach relies only on a single output voltage measurement to reduce the system cost as well as measurement noise and disturbance injected by output current and/or inductor current measurements. To reduce the controller sensitivity to the system parameters, the proposed controller is developed for...
Nowadays, the stability of power systems becomes a crucial research subject and it is very important issue for large scale systems. The transient stability of a long transmission system can be significantly realized by the excitation systems control using generally an automatic voltage regulator (AVR) and a power system stabilizer (PSS). In this paper, the improvement of the power system stability...
Due to varying and intermittent nature of wind resource, grid connected wind farms pose significant technical challenges to power grid on power quality and voltage stability. Wind farm Q-V characteristic curve at the point of interconnection (POI) can offer valuable information for voltage control actions and provide essential indication about voltage stability. Data driven analytics is a promising...
This paper considers the problem of designing decentralized Volt/VAR controllers for distributed energy resources (DERs). The voltage-reactive power characteristics of individual DERs are obtained by solving a convex optimization problem, where given performance objectives (e.g., minimization of the voltage deviations from a given profile) are specified and stability constraints are enforced. The...
This paper proposes the high voltage gain quadratic boost converter for supplying standalone ac loads using renewable power supply that generates dc power at low voltages. A fixed frequency SMC has been proposed in this paper to regulate the dc link capacitor voltage. The conventional SMC has variable switching frequency while leads to the damage of passive components as well as unpredictable response...
This paper presents the comparative analysis for the improvement of transient stability by using various combinations of multilevel converter fed system and super conducting magnetic energy storage system which are controlled by Artificial neural network and fuzzy logic controllers. The effective means of control is obtained by analyzing various cases in improving the transient stability. The load...
In this paper, it is presented a procedure to simplify the well-known average model as well as to approximate the controller design for a Pulse-Width-Modulation (PWM) based power converter that transforms energy from some DC source (such as batteries or fuel cells) into an AC voltage source. The power converter studied is formed by two stages: a DC-DC bidirectional converter (boost) and a DC-AC H-bridge...
The stability of the observer is an important concern for observer based sensorless control. This paper presents the stability analysis of observer used for high speed position sensorless control of surface permanent magnet synchronous motor (SPMSM). In this paper, extended induced voltage observer is utilized for high speed senseless control of SPMSM. The purpose of this study is to analyse the stability...
In order to improve fault recovery characteristic of high-voltage direct current transmission system(HVDC), this paper proposes voltage dependent current order limiter(VDCOL), optimizing arc extinguishing angle controlling and adopting SVC reactive power compensator and so on to improve fault recovery feature after analyzing the main factors influencing fault recovery characteristic. This paper makes...
This paper presents load shedding scheme based on voltage instability index to prevent voltage collapse. For assessing effective of method, the scheme requires reliable voltage instability indicator which can evaluate the dynamic behaviors in system voltage stability for deciding the necessary control action. Hence, synchrophasor data using Phasor Measurement Units (PMUs) are used in calculation process...
Generally, the mathematical model of DC micro-grids (DCMGs) with bi-directional voltage source converter (VSC) is time-varying due to the switching action. The time-varying model is very complicated for controller design or stability analysis. As a result, this article presents how to derive the mathematical model using a combination between DQ method and the generalized state-space averaging method...
In recent years the significant improvementin micro grid technology has led to the utilization of thelocal distributed sources. The microgrids also have agreater role in the minimization of transmission losses. During power blackouts they serve as a main source ofpower for few emergency loads. It is common that usuallythe AC grids are preferred over DC grids to transmitpower over long distances in...
Microgrids gathered a lot of attention in the last decade and are believed to be the future power systems. The renewable energy sources can be easily integrated into the Microgrid. Renewable energy sources such as PV, wind and fuel cells are usually connected through voltage-source inverters in the Microgrid. In order to share the same loads, these inverters are connected in parallel and to achieve...
Application of static synchronous series compensator (SSSC) based damping controller for enhancement of power system stability is throughout investigated in this paper. SSSC is effectively utilized for power flow control in the power system. A SSSC-based damping controller is proposed for rotor angle stability enhancement and to eliminate the power oscillation damping in power system. To improve the...
An inverter with an output LC filter can be used for generation of sinusoidal output voltage with low harmonic distortion, suitable for distributed generation systems. However, with the growing number of electronic devices with rectifiers at the front end of their power supply, the nonlinearities of the load current in power systems are increasing. As such designing an inverter system with a nonlinear...
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.