The paper presents the results of vibroacoustic investigations and the measurements of the acoustic pressure level (noise) of a transformer model. The measurements were taken at a full transformer load in two operation conditions: at a producer packeted core and at unpacketed core. Unpacketing consisted in loosing the screws pressing the particular core plates. Mechanical vibrations were regist...

In this paper, a compact tri-band impedance transformer by utilizing stubbed coupling line for matching a load at three arbitrary frequencies is proposed. The transformer is composed of two parts, and each part is constructed from parallel-coupled transmission lines. Two structures with different configurations of the proposed transformer have been given and analyzed. Then, the close-form equat...

This paper presents a method for the design of shell-type, single-phase distribution transformers to obtain the manufacturing specifications. The method is simple, efficient and accurate. By an exhaustive analysis, it is concluded that the obtained solution is the global optimum. The following constraints are imposed: excitation current, no-load losses, total losses, impedance and efficiency. T...

leads and windings due t o eddy cu r ren t s induced in the conductors by t h e al ternat ing magnetic field. The leads and windings a r e connected in series, therefore, t he high-frequency resistance of t he transformer R t is An accurate, analyt ical method is proposed f o r calculating the lead and winding high-frequency resistance of complex transformer constructions. High-frequency resist...

A conventional high power DC power supply systems consist of a three-phase diode rectifier followed by a high frequency converter to supply loads at regulated DC voltage. These rectifiers draw significant harmonic currents from the utility, resulting in poor input power factor. In this paper, a DC power supply based on dual-bridge matrix converter (DBMC) with reduced number of switches is p...

We consider the possibility of passing high-frequency signals past power transformers forming part of an electrical grid. We first model a transformer, including its laminated core, to obtain asymptotic behaviour of currents and voltages in the secondary circuit. Having got this we are able to determine the effects of different by-pass mechanisms which might be tried to get the high-frequency s...

The systolic array is frequently used in accelerators for neural networks, including Transformer models that have recently achieved remarkable progress natural language processing (NLP) and machine translation. Due to the constraints of FPGA EDA (Field Programmable Gate Array Electronic Design Automation) tools limitations design methodology, existing deployment often cannot achieve high freque...

Events such as lightning, switching of vacuum circuit breaker or operations in gas insulated substation (GIS) generate high frequency overvoltages. An equipment a transmission distribution system has to be protected against phenomena. Unfortunately, the traditional transformer models available Electromagnetic transient simulations program (EMTP-like) software packages are not capable representi...

Variable frequency transformer (VFT), introduced recently is a flexible asynchronous ac link which is used in power transferal process between asynchronous power system grids. VFT was first installed at Langlois substation, which interconnects the Hydro-Québec (Canada) and New York (USA) systems. The torque of the rotary transformer is externally altered in order to control the direction and ma...