SAN ANTONIO - The Electrical Reliability Council of Texas (ERCOT) is requesting Texans to conserve electricity from 6 a.m. to 10 a.m. due to freezing temperatur
This paper considers energy delivery by a Hybrid Access Point (HAP) to one or more Radio Frequency (RF)-energy harvesting devices. Unlike prior works, it considers imperfect and causal Channel State Information (CSI), and probabilistic constraints that ensure devices receive their required amount of energy over a given planning horizon. To this end, it outlines two novel contributions. The first is a chance-constrained program, which is then solved using a Mixed Integer Linear Program (MILP) coupled with a Sample Average Approximation (SAA) method. The second is a Model Predictive Control (MPC) solution that utilizes Gaussian Mixture Model (GMM) and a so called backoff that is used to tighten probabilistic constraints. The results show that the performance of the MPC based solution is within 8% of the optimal solution with a probability of 90.8%.
The recloser-fuse coordination of the distribution networks equipped with distributed generators (DGs) may be jeopardized by using the conventional overcurrent protection strategies thus degrading the network reliability. This research article focuses on the design of a protection coordination strategy based on the dual-setting directional recloser (DSDR) for the effective implementation of a fuse-saving scheme in distribution networks (DNs). The proposed DSDR-based protection strategy will assist the network operators by providing a flexible coordination range along with more accurate protection settings to meet the protection coordination requirements. The performance of the proposed protection scheme has been validated through its implementation on IEEE standardized test systems and a comparative analysis has been drawn to demonstrate its effectiveness. Furthermore, this research work concentrates on the economical design of the protection strategy for distribution networks by utili
Despite the substantial reliability and power quality improvements, the proliferation of distributed energy resources (DERs) can introduce many protection complexities in distribution networks. This research article presents a comprehensive investigative analysis of the distributed generation (DG) impacts on the protection performance of the distribution network. Various protection coordination case studies have been analyzed under different operating conditions by varying the DG penetration level or the fault conditions to highlight the potential risks of the protection networks. The severity of the risks is evaluated by considering the DG locations, protection settings, and fault types/impedance parameters on a standardized IEEE 13 node test feeder. The subsequent protection hazards are examined for the mutual coordination of the overcurrent (OC) relays, auto-reclosers, and series fuses in distribution networks along with the differential protection issues for DC bus system. Furtherm
Although it is commonly assumed that power swing is symmetrical and will have identical effects on all three-phase voltages and currents, there is another type of power swing, which is asymmetrical and mainly occurs during single-pole tripping (SPT), the impact of which on power systems integrated with the inverter-based resources (IBRs) has not been investigated so far. Since the likelihood of the occurrence of asymmetrical power swing is increasing in todays heavily loaded transmission lines, this paper investigates the impact of IBR integration on the performance of distance protection during single-pole tripping. Furthermore, a new scheme is proposed to detect earth faults that occur during asymmetrical power swings to enhance the performance of power swing blocking (PSB) functions. To do so, the superimposed component of the zero-sequence current during SPT is extracted. Then, the moving average window is used to calculate the average of both zero-sequence current and its superimp