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.
Double-Fed Induction Generators (DFIG's) driven by wind turbines are today the state of the art wind generators and are required to provide advanced functionalities in order to support the grid and comply with technical regulations. In this paper, we propose a novel control scheme for a wind turbine driven DFIG with an integrated energy storage. The control scheme is based on nonlinear control methods...
In this paper we develop a nonlinear coordinated controller for a battery storage and a generator excitation that guarantees terminal voltage regulation and transient stabilization of the generator. The proposed controller is based on a new state transformation that enables the derivation of a Multi-Input Multi-Output (MIMO) feedback-linearizing controller. First, we define the state-space transformation...
Integrating additional wind energy into the existing power system may cause wind curtailment due to the system operational constraints and reliability requirements. Effective ways to mitigate this problem are to use energy storage or increase transmission capacity. In this paper, the impacts of coordinating with pumped storage and increasing transmission capacity on wind output curtailment mitigation...
Hydropower is the largest producer of renewable energy in the U.S. More than 60% of the total renewable generation comes from hydropower. There is also approximately 22 GW of pumped storage hydropower (PSH). Conventional PSH uses a synchronous generator, and thus the rotational speed is constant at synchronous speed. This work details a hydrodynamic model and generator/power converter dynamic model...
With the increasing penetration of renewable resources in power systems, more operational flexibility is required to deal with the uncertainty of intermittent generation. In particular, fast acting regulation reserves are needed to maintain the load-generation balance. This paper focuses on evaluating the benefits of energy storage in providing regulation services for real-time operation. Among the...
This paper presents a battery-based storage (BBS) for wind generator (WG) system. The BBS is composed by an Asymmetric Cascaded H-Bridge Multilevel Inverter (ACMI) with staircase modulation. The proposed structure is connected in parallel to the whole WG system. Such connection plus the use of the ACMI allow a reduction in the power losses, compared to the commonly found storages connected where the...
A novel passivity-based controller using three time-scale separations is introduced for variable speed drives of flywheel energy storage systems. The time-scale separation between the power electronics, the electrical machine variables, and the mechanical machine variables is used in order to design a nested three-layer controller. Since the dynamics of the variable speed drive are non-linear, the...
If distributed generators are introduced on a large scale to the power system, various impacts on the power system are expected. For example, difference between power supply and power demand is occurred in low-voltage distribution system. Digital Grid can solve these problems by performing a power interchange between the power systems. In this paper, we conducted verification and evaluation for Digital...
Future distribution networks with high penetration of renewable resources and energy storage can provide ancillary services such as frequency regulation. This study proposes a secondary frequency control scheme based on aggregated active distribution networks. The proposed method is based on hierarchical coordinated control of bidirectional controlled energy storages under islanding situations. The...
Recently, new standards and incentives are spreading the installation of energy storage systems (ESSs) to promote, inter alia, the renewable energy sources (RES) penetration. ESSs can be used for supporting producers and distribution system operators to give more flexibility to the grid in terms of dispatching capability of RES, load shifting, peak shaving, ancillary services. This paper proposes...
In this paper we design a cooperative control scheme for a wind Double-Fed Induction Generator (DFIG) with an integrated energy storage. The proposed control scheme can enable the wind generator to provide new advanced capabilities and support to the grid. More specifically, we design a controller for the rotor side converter (RSC) that guarantees maximum power point tracking (MPPT) while the controller...
This paper first puts the challenges from design constraints imposed by mission load requirements on future naval surface combatants into context. Moreover, it provides results from experiments at the three partner universities designed to de-risk emerging medium voltage DC (MVDC) technology based systems and to provide validated models for future systems studies. These experiments are carries out...
From local utility grids to electric ships, providing power to an ever increasing variety and magnitude of loads requires power grids that are more flexible, resilient, and efficient than ever before. In many cases, these systems must serve loads that are nearly equal to and occasionally exceed peak generation capacity. As a result, it is critical that these power systems and their controls are analyzed...
A principle motivation for the development of early-stage shipboard power system simulation techniques is the need to perform time-domain simulation during the early design stage. In particular, there is a need to understand the performance of a candidate system during challenging situations involving dynamic load profiles and disruptive conditions in order to assess the system dependability. An early-stage...
In this paper, an entire formulation of a multiperiod optimal power flow is presented. The standard timeindependent AC Optimal Power Flow (AC-OPF) includes voltage, line capacity and generator limits for each time step. Additionally, time-dependent constraints like generator rampings, stored energy or energy contracts are crucial for time constrained optimization. A comparison of methods for modeling...
The increasing integration of Renewable Energy Resources (RER) and the role of Electric Energy Storage (EES) in distribution systems has created interest in using energy management strategies. EES has become a suitable resource to manage energy consumption and generation in smart grid. Optimize scheduling of EES can also maximize retailer's profit by introducing energy time-shift opportunities. This...
Modeling of non-utility facility with generation and battery storage is presented. The operation strategy for non-utility facility is determined by solving a daily generation scheduling problem under a price-taking scheme. Numerical simulations are performed under various scenarios. It is shown that the optimal strategy is complex when either fuel supply is limited or electric utility allows buy-back...
This paper deals with the very short time predictive control of a hybrid microgrid (μG). The hybrid μG is characterized by the presence of two sections operating in alternating current (AC) and in direct current (DC), respectively. The proposed very short time predictive control is based on an optimal strategy focused on the coordination of loads and energy resources and aimed at minimizing the cost...
This paper describes a current study to assess the feasibility of developing CAES storage caverns in salt beds in the north east of Ireland. Thin-bedded salt is regarded as inferior to domal or thick-layered (diapir) salt for cavern storage. However, given the relative scarcity of diapirs and increasing demand for underground gas storage (UGS) capacity, there has been a recent increase in the development...
Grid-interfacing converter systems with enhanced voltage quality are proposed for dc microgrid applications in this paper. By adapting the conventional series-parallel structure, a group of grid-interfacing system topologies and their control for the purpose of interfacing local generation/dc microgrid to the grid, or interconnecting dc microgrids. First step includes the integration of required number...
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.