Overvoltage is one of the issues in distribution grids with high penetration photovoltaics (PVs). Centralized or droop-based methods active power curtailment (APC) and/or reactive control PVs are viable solutions to prevent overvoltage. This article proposes two distributed PV inverters, which based on nodal sensitivities. Then, performance proposed compared commonly used methods, i.e., a metho...

we solve the coupled mode equations governing the chalcogenide nonlinear fiber bragg gratings (fbgs) numerically, and obtain the bistability characteristics. the characteristics of the chalcogenide nonlinear fbgs such as: switching threshold intensity, bistability interval, on-off switching ratio are studied. the effects of fbg length and its third order nonlinear refractive index on fbg charac...

This paper describes methodology for the computation of the electromagnetic transients in the high voltage substations, taking into account transients on the substation grounding system. Simulation technology is based on the system decomposition. Interconnections between different subsystems are done in each time step using Thevenin equivalents. Frequency dependent impedance of grounding conduc...

We report the first use of cobalt aluminophosphate (CoAPO5) as a water oxidation catalyst. A decrease in the overvoltage by about 0.2 V with respect to catalyst free FTO has been observed. Additionally, we show that CoAPO5, deposited on ITO or Pt, can also act as a photo-electro-catalyst, as it generates enhanced oxidation currents in the presence of light starting from a bias of +0.8 V vs. Ag/...

This paper presents the use of curtailment to allow more wind or solar power to be connected to a distribution network when overcurrent or overvoltage set a limit. Four case studies, all based on measurements, are presented. In all cases the hosting capacity method is used to quantify the gain in produced energy for increased levels of distributed renewable energy resources. A distinction is ma...

Ferroresonance is a phenomenon that involves high distorted levels of overvoltage and overcurrents. During the last decades, the three-phase ferroresonance research has suffered several changes due to the continuously changing equipment and network. This paper analyses every main factor that is somehow related with the origin, consequences and the preventive decisions that may lead us to avoid ...

Design of a 3.3V comaptible 2.5V TTL-toCMOS bidirectional I/O buffer is proposed. Gate oxide protectiom was implemented without active voltage degradation, which reduces static and dynamic current levels and improves noise immunity for the low voltage circuit of this kind. Fast removal of stored charge further improve gate oxide protection and circuit recovery from overvoltage condition. Circui...

During the past years, governments throughout the world have been encouraging the installation of renewable energy systems to cope with environmental goals. In this framework, there has been a significant increase in the number of energy producers on the consumers’side, majorly due to photovoltaic and wind energy microgeneration.This has brought some concerns in voltage control on buses far awa...