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.
This paper presents a predictive control strategy to control the load current in a single-phase AC-AC converter. The proposed technique consists on a prediction estimation to choose the available switching state of the converter to be applied one step ahead. By considering a cost function, the best switching state to be applied into the converter the next sampling period is selected. All this is done...
The scavenging of electrical energy from surrounding environment has a number of attractions, and vibration energy is seen as one of the most potential sources. Switched damping is a method to improve the operational bandwidth of an electromagnetic energy harvester by alternatively switching the values of electrical damping coefficients of the device at different quadrants during oscillation. From...
State estimation has become an important task in modern energy/ distribution management systems. However, the state estimation is not very popular in modern unbalanced three-phase distribution systems. This paper proposes a method for three-phase state estimation with detailed three-phase modelling of system components including switches and star and delta connected loads. This method is then tested...
Increasing redundant paths in transmission grids has always been thought to be a tool to enhance service reliability. However, network equations by intertwining power flows through redundant paths impose more limits on systems with more redundancy. Accordingly, autonomous removing of a few lines may relief capacity limit violations in some contingency events thereby enhancing service reliability....
In this paper, Steinmetz principle has been implemented for the phase current balance of three phase networks by supplying power to both slow as well as fast varying delta connected linear and unbalanced loads at unity power factor. The reactive power compensation of the proposed technique delivers close to unity power factor and also helps active load balancing of the three phase currents efficiently...
Hardware-in-the-loop (HIL) is known as an efficient simulation approach allowing the test of control systems before implementation, where some of the control-loop components are implemented in real hardware device and some are simulated. Typical, ordinary Input/Output ports are used as an interface between the plant simulation and the embedded system under test. However, this kind of communication...
Nondisruptive demand response programs often result in complex and fast aggregated load dynamics, which may lead to severe impact on the distribution and transition systems. Accurate modeling of aggregated load dynamics is of fundamental importance for systematic analysis and design of various demand response strategies. Existing methods mostly focus on simple first-order linear Thermostatically Controlled...
This paper propose a Takagi-Sugeno (T-S) fuzzy based reference model to deal with Maximum Power Point Tracking (MPPT) problem applied to a photovoltaic (PV) system. An MPP searching algorithm is used in the global MPPT structure to generate the optimal output boost voltage. It provides a good MPP tracking performance in the case of rapidly changing climatic conditions, and it reaches the maximum power...
Now a day's use of portable devices increasing more. Such as cellular phones, digital cameras and high efficient power managing modules etc. are demanding for low output voltage ripple with fast transient response. The terminal voltage of the battery used in portable applications varies particularly depending on state of their charging conditions. In this paper, Li-ion battery is considered that provides...
In this paper a new topology for boost converter as well as an efficient control system based on state space modeling is presented in order to improve the power factor of the network. The main objective of this study is to adjust the real power of DG resources connected to network. The proposed power factor correction (PFC) boost converter includes two loops for current and voltage control and on...
In modern times daily increase in load has resulted in transmission network being operated beyond its stability limit. This has considerable impact on power system operations, as it may lead to outage of transmission lines, which includes sudden switching out of lines and its consequent alteration of the structure of the transmission system. In this paper, line vulnerability is investigated through...
This study presents the development processes of a high-efficiency two-output flyback-converter. The detailed design phases are presented together with encountered design obstacles, limitations and the methods to overcome them. Despite their widely use in industry, studies on high-efficient flyback converter design still remains a need. Most of the flyback converters are designed with multi outputs...
In this paper, a component efficient multilevel rectifier is modeled and controlled using Model Predictive Control (MPC) technique. The recently introduced Capacitor Tied Switches (CTS) converter structure features two distinct dc-load terminals which can operate at different voltage levels while experiencing high voltage levels at the ac-side terminals. The CTS converter structure inherits attractive...
This paper presents the modelling and control strategy for a new high-power multilevel multipulse medium frequency-isolated dc-dc converter. The new converter is composed by a Modular Multilevel Converter (MMC) associated to an isolated Multipulse Rectifier (MR). Its application is targeted to non-conventional distribution and sub-transmission systems, while operating at tens of kVs and a few MWs...
In the simulation study of DC micro grid with a large number of isolated bidirectional DC-DC converters, both the calculation time cost and the harmonic performances need to be considered. However, traditional simple models do not have the harmonic performance, and complicated models do not have fast simulation speed. In this paper, a novel fast equivalent model of isolated bidirectional DC-DC converters...
The purpose of this paper is to propose the digital control method that is comprised of the fast P control and model control for an improvement of the transient response of the dc-dc converter. The electronic devices are required the operation in the standby mode and the quick return to the active mode. The fast transient response of the dc-dc converter in such condition is important. In this paper,...
The paper focuses on the role of disconnectors for load transfer duties in the operation of MTDC meshed grids. As there are no topology existing today and no standard, some switching duties are presented for which disconnectors could act instead of using circuit breaker. Based on an empirical model relying on tests performed in air, severity of the different switching duties are presented and first...
This paper presents a technique on how two simulators at different levels of abstraction can interact for the design and sizing of a booster power unit. The system is constituted by an ultracapacitor bank and a converter to boost voltage sags in a railway application. Full steps to determine Thevenin equivalent circuit of a dc railway is obtained based on exact modeling of the system components. Example...
Recently, Model Predictive Controller (MPC) becomes the most attractive control in power electronics and drives applications. It is incorporated in Z-Source Inverter family (ZSI) where each of capacitor voltage, inductor current and output load currents could be controlled at their setting points' values. In this paper, a proposed algorithm for qSZI is introduced to simplify the system through reducing...
Distribution systems have been gradually improved with new technologies. They have been upgraded from the traditional system with low-level control to a smart-grid system with high-level control. In the present work, a mathematical model of an unbalanced three-phase distribution system, including ZIP loads and other components of distribution systems is used, and a Genetic Algorithm (GA) -based Distribution...
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.