The main goal of this paper is the determination of the effect of the metal oxide varistor (MOV) on various ferroresonance modes including fundamental resonance, subharmonic and chaos mode which are generated in electrical power systems. Chaos theory is used for analyzing this effect. Also, the bifurcation, phase plan diagram and time domain simulation are used for this purpose. The proposed po...

Since power transformer is a complex and critical component of the power transmission and distribution system, their reliability is crucially important for the energy system operation. So, there is an increasing interest in applying monitoring systems and on line diagnosis methods to transformers, as these are one of the most expensive and critical apparatus of a power system. Detecting failure...

in working process of power transformer, which directly affects the safe operation of transformer oil temperature as well as the stability of the network, so vital to transformer oil temperature detection and control. Based on single chip and chip design of digital temperature measurement transformer oil temperature of an intelligent control system. The system uses a digital temperature sensor ...

a simple method is described for analysis of transients in power network. the method is developed for analysis of transformer and generator winding resonances due to their interaction with transmission lines caused by switching surges. the method is already used for calculation of overvoltages which had resulted in damages in the transformer winding of a hydro power plant. nonlinearity in the i...

Reliable energy flow is paramount and power transformers are critical, and costly, assets in the grid. As an asset class, power transformers constitute one of the largest investments in a utility’s system. For this reason transformer condition assessment and management is a high priority. In several parts of the world the transformer fleet is operating beyond its design life and with higher ave...

A novel Inductive Contactless Energy Transfer (ICET) system is presented in this paper. The energy is transferred using a rotatable air gap transformer and a power electronic converter. To minimize total losses of the system a series resonant circuit is applied, assuring zero current switching condition for IGBT power transistors. The analytical expression of the transfer dc voltage gain is giv...

With the evolution of Process Bus (IEC 61850-9-2), there is a need to assess the performance of protection schemes using process bus against those where traditional copper wires are implemented. Differential protection is the fundamental and most commonly used protection for transformers, motors and generators. In this paper a power system is modelled in SimPowerSystems and is executed in real-...

Transformer fault diagnosis is an interesting subject for plant operators due to its criticality in power systems. There are several international standards available to interpret power transformer faults based on dissolved gas analysis. In certain cases these standards are not able to provide correct diagnosis. There are several soft computing techniques available for modelling transformer fau...

As an integral part of the Smart Grid, smart transformers both work independently to constantly regulate voltage and maintain contact with the smart grid in order to allow remote administration if needed and to provide information and feedback about the power supply and the transformers themselves. Through a process known as voltage optimization, a smart transformer provides the exact amount of...

Reliability of a power system is considerably influenced by its equipments. Power transformers are one of the most critical and expensive equipments of a power system and their proper functions are vital for the substations and utilities. Therefore, reliability model of power transformer is very important in the risk assessment of the engineering systems. This model shows the characteristics an...