This paper describes a procedure for frequency dependent modeling of power transformers from measured terminal characteristics. The admittance matrix is measured in the frequency domain using a network analyzer and a dedicated measurement setup. Subsequent approximation of the admittance matrix with rational functions using Vector Fitting gives an EMTP-type compatible model suitable for transie...

A transformer is a vital component in any power system network and its catastrophic failure may cause disturbance in the proper operation of electrical power system network. Therefore, it requires continuous monitoring and diagnostics of its operation. This paper presents the several on-line and off-line techniques related with internal winding fault detection in transformers. This paper also r...

This paper presents an analytical method to compute the leakage inductances of power transformers with a turn-to-turn winding fault. A leakage inductance model to represent the transformer with faulty turns is also proposed. The results obtained from the application of the analytical method are validated by using data obtained from finite-element analysis and experimental tests.

A segment of an existing Belgian medium-voltage distribution system is used to study the power quality and voltage stability with different distributed generation (DG) technologies (Figure C16.1). The system includes one transformer of 14 MVA, 70/10 kV and four cable feeders. The primary winding of the transformer is connected to the transmission grid and can be considered as an infinite node. ...

Detection and removal of incipient faults in power transformer winding is essential because minor faults may develop and lead to major faults and finally irretrievable damages occur. This research article presenta a new, simple and incipient fault detection technique, which is based on symmetrical component approach. Using this protection technique, it is possible to detect minor turn-to-turn f...

Single winding self-driven synchronous rectification (SWSDSR) approach is a new driving circuit that overcomes the limitations of the traditional driving schemes, becoming an interesting alternative to supply new electronic loads as microprocessors. Traditional self-driven synchronous rectification (SDSR) technique has shown very good performance to improve efficiency and thermal management in ...

Role of winding shielding on the parasitic capacitances of transformer and common-mode (CM) noise is analyzed in details when considering the effects of the secondary side noise source. Based on the proposed model of CM noise, two novel techniques to cancel CM noise by balancing noise is given; experiment results show CM noise is greatly reduced when the techniques are adopted.

Power transformers are key components in electrical power supplies and their failure could cause severe consequences on continuity of service and also generates substantial costs. Identifying problems at an early stage, before catastrophic failure occurs, is a great benefit for reliable operation of power transformers. Frequency Response Analysis (FRA) is a new, well-known and powerful diagnost...

Transformer protection is critical issue in power system as the issue lies in the accurate and rapid discrimination of magnetizing inrush current from internal fault current. Artificial neural network has been proposed and has demonstrated the capability of solving the transformer monitoring and fault detection problem using an inexpensive, reliable, and noninvasive procedure. This paper gives ...