This paper combines the fundamentals of an electrical grid, such as flow allocation according to Kirchhoff’s laws and the effect of transmission line reactances, with spectral graph theory, and expresses the linearised power flow behaviour in slackbus independent weighted graph matrices to assess the relation between the topological structure and the physical behaviour of a power grid. Based on...

We present recent results concerning distance determinations based on the two most popular primary distance indicators, namely classical Cepheids and RR Lyrae. We discuss the problems affecting the Cepheid distance scale, and in particular the dependence of fundamental Period-Luminosity (PL) and Period-Luminosity-Color (PLC) relations on the metal content. The key advantages in using the K-band...

Fault diagnosis is a vital discussion in power systems restoration. Recently, much research endeavors have been done for fault section diagnosis of power systems by using several techniques, such as rule-based expert system, logic-based expert system, fuzzy relation based expert system, neural network, optimization techniques based approach, etc. They diagnose the fault from different ways. How...

In order to meet cost targets for hybrid electric (HEV), Plug-in hybrid electric (PHEV), and allelectric vehicles (EV), an improvement in the battery life cycle and safety is essential. One practical approach to improve performance is to use power electronics intensive cell equalizer, in conjunction with on-board energy storage devices. A new technique based on buck-boost topology to equalize a...

The connection of wind turbines to the distribution networks may affect the voltage quality offered to the consumers. One of the factors contributing to this effect are the rapid variations of the wind turbine output power, which cause respective fluctuations in the supply voltage, referred to as flicker. This paper presents a neural network based model for wind turbine flicker emission calcula...

Voltage instability is a major concern in operation of power systems and it is well known that voltage instability and collapse have led to blackout or abnormally low voltages in a significant part of the power system. Consequently, tracking the proximity of the power system to an insecure voltage condition has become an important element of any protection and control scheme. The expected time ...