Capability of TCSC on SSR Mitigation

TCSC (Thyristor-Controlled Series Compensator) has been used in modern power systems to increase power transfer and system stability. Besides, due to its controllable feature, TCSC has been used to work as a solution to sub-synchronous resonance (SSR) problems. However, it is not clear so far whether TCSC’s inherent characteristic can avoid SSR and its effectiveness for SSR damping. In this paper, an equivalent circuit of TCSC is used to better understand how TCSC performs at sub-synchronous frequency ranges. Therefore, interactions of TCSC behaviors and SSR components can be viewed individually. The effects of TCSC operation interfered by sub-synchronous components are discussed. Results show that TCSC has the capability to damp SSR, but this capability can be deteriorated if TCSC firing logic cannot be effectively maintained

A composite iterative algorithm for common fixed points for a finite family of nonexpansive mappings and applications

AbstractThis paper is concerned with a new composite iteration approximating to common fixed points for a finite family of nonexpansive mappings in Banach spaces which have a uniformly Gâteaux differentiable norm. Utilizing the iterative algorithm, we obtain the strong convergence theorems for a finite family of nonexpansive mappings. Furthermore, the problem of image recovery is considered in the above result. Our results extend and improve the corresponding results

A calculation model of charge and discharge capacity of electric vehicle cluster based on trip chain

The rapid response characteristics and high-speed growth of electric vehicles (EVs) demonstrate its potential to provide auxiliary frequency regulation services for independent system operators through vehicle-to-grid (V2G). However, due to the spatiotemporal random dynamics of travel behavior, it is challenging to evaluate the ability of EV cluster to provide ancillary services under the premise of reaching the expected state of charge (SOC) level. To address this issue, a novel calculation model of charge and discharge capacity of EV cluster based on trip chain with excellent parallel computing performance is presented in this work. Following the introduction of the characteristic variables of the proposed trip chain model, the user’s continuous travel behavior in a time scale of several weeks is simulated. In particular, a bidirectional V2G scheduling strategy based on the five-zone map is designed to guide the charging and discharging behavior of EVs, where the expected SOC levels are guaranteed. The results of a 3-week travel simulation verify the effectiveness of the presented model in coordinating the V2G scheme and calculating the charge and discharge capacity of the EV cluster

Figure of Merit and Different Combinations of Observational Data Sets

To constrain cosmological parameters, one often makes a joint analysis with different combinations of observational data sets. In this paper we take the figure of merit (FoM) for Dark Energy Task Force fiducial model (CPL model) to estimate goodness of different combinations of data sets, which include 11 widely-used observational data sets (Type Ia Supernovae, Observational Hubble Parameter, Baryon Acoustic Oscillation, Cosmic Microwave Background, X-ray Cluster Baryon Mass Fraction, and Gamma-Ray Bursts). We analyze different combinations and make a comparison for two types of combination based on two types of basic combinations, which are often adopted in the literatures. We find two sets of combinations, which have strong ability to constrain the dark energy parameters, one has the largest FoM, the other contains less observational data with a relative large FoM and a simple fitting procedure.Comment: To be published in Phys.Rev.D, 20 pages, 4 table