The knowledge of DC time constants in fault currents at system nodes is important to design the protection system and validate the calculation models for power system simulations. In this paper, we present methods to estimate Thévenin’s impedance and DC time constants in fault currents with application to disturbance records. Additionally, a comparison between both parameters is shown. We demon...

Commutation failure is a common fault for line-commutated converters in the inverter. To reduce the possibility of commutation failure, many prediction algorithms based on alternating current (AC) voltage detection have already been implemented in high voltage direct current (HVDC) control and protection systems. Nevertheless, there are currently no effective methods to prevent commutation fail...

Abstract: In this paper, a new topology is developed for a three-phase four-wire (3P4W) distribution system utilizing a zig-zag transformer along with three-phase threewire (3P3W) Unified Power Quality Conditioner (UPQC).In this proposed topology the neutral point of the star connected transformer, used for the connection of series active power filter (APF) of 3P3W UPQC, is utilized as a fourth...

This paper proposes a new algorithm for blocking the operation of Indirect Symmetrical Phase Shift Transformer (ISPST) differential relay when subjected to different operating conditions except internal fault condition. The proposed algorithm is amalgamation of Phase angle shift (PAS) threshold and Optimal Radial Basis Function Neural Network (ORBFNN). PAS between source and load side currents ...

The aim of this research article is to determine the way to install surge arresters close to a power transformer to provide protection against lightning overvoltage. Depending on the length of the cables used in the installation, the insulation levels in base insulators of surge arresters and bushings of transformers change according to the voltage they support. For validation purposes, the vol...

The high amplitude and steep overvoltage generated by the breaking of vacuum circuit breaker in wind farm damages inter-turn insulation transformer. There is a certain difference between simulation results traditional reignition model measured overvoltage. It necessary to improve simulate condition transformer more accurately then select appropriate protection measures. In this paper, based on ...

The ideal drive beam current profile for the plasma wakefield accelerator (PWFA) has been predicted by 1D and 2D simulations to be characterized by a triangular ramp that rises linearly from head to tail, followed by a sharp drop. A technique for generating such bunches experimentally was recently demonstrated. We present here an adaptation of this scheme to generate ramped bunches using the 23...

This paper presents an efficient wavelet and neural network (WNN) based approach for distinguishing magnetizing inrush currents from internal fault currents in three phase power transformers. The wavelet transform is applied first to decompose the current signals of the power transformer into a series of detailed wavelet components. The values of the detailed coefficients obtained can discrimin...

OF THESIS MATHEMATICAL MODEL FOR CURRENT TRANSFORMER BASED ON JILESATHERTON THEORY AND SATURATION DETECTION METHOD Current transformer saturation will cause the secondary current distortion. When saturation occurs, the secondary current will not be linearly proportional to the primary current, which may lead to maloperation of protection devices. This thesis researches and tests two detecting m...