RU2562067C1 - Magneto-electric ring transformer with magnetic biasing - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: magneto-electric ring transformer with magnetic biasing represents a structure made in the form of a magneto-electric capacitor connected to an input circuit, the dielectric material of which is volumetric magnetostrictive piezoelectric composite material in the form of a flat ring, to the inner and outer surfaces of which electrodes are applied, and inductance coil wound on it. When alternating voltage is being supplied to the capacitor, in a piezoelectric phase of composite material there created are mechanical stresses that are transmitted to a magnetostrictive phase, and as a result, magnetisation intensity is changed, which leads to induction of EMF in the inductance coil wound on the specimen. Additionally, a capacitor from which a variable output signal is picked up is connected to the output circuit. At the same time, the inductance coil is used for creation of a magnetic bias field.

EFFECT: improving transformer action efficiency.

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Description

The invention relates to electronics and can be used in AC circuits for voltage conversion.

In the classic version, the transformer consists of a magnetic circuit with two or more electrical windings wound around it. Energy is transferred from one circuit to another due to the phenomenon of mutual induction [(MV Nemtsov, Electrical Engineering and Electronics, Moscow, Higher School, 2007, 560 pp. Chapter 9).]. Since the voltage removed from the output winding is proportional to the number of turns in it, this leads to an unjustified increase in the size of the device and its bulkiness in industrial design.

An autotransformer containing one winding is also known, but the lower voltage winding is part of the higher voltage winding, as a result of which there is no galvanic isolation between the input and output circuits.

The closest technical solution adopted for the prototype is a ring magnetoelectric transformer, which is a structure made in the form of a magnetoelectric capacitor included in the input circuit, the dielectric of which is a volume magnetostrictive piezoelectric composite material in the form of a flat ring, on the inner and outer surfaces of which are applied electrodes, and the output signal is removed from the inductor [see RU No. 128775, H01F 19/04, dated 05.25.2013].

A disadvantage of the known ring magnetoelectric transformer is the absence of a magnetization field, as a result of which, when converting the electric field to magnetic, a quadratic magnetoelectric effect occurs [see YES. Filippov, V.M. Laletin, T.O. Firsova. Nonlinear magnetoelectric effect in composite multiferroics // Solid State Physics, 2014, Volume 56, no. 5 sec 944-948].

The problem to which the claimed proposal is directed is to improve the performance and increase the efficiency of the device.

To solve this problem, a ring magnetoelectric transformer with magnetization is proposed. It is known that the magnitude of the magnetoelectric effect very much depends on the magnetization field, and the so-called field dependence of the effect has a pronounced maximum [see YES. Filippov, V.M. Laletin, G. Srinivasan. Low-frequency and resonant magnetoelectric effects in bulk composite structures of nickel ferrite - lead zirconate-titanate // Journal of Technical Physics, 2012, v. 82, No. 1, p. 47-51]. This effect is proposed to be used in the inventive device.

To explain the invention, FIG. 1, which shows a General view of a ring magnetoelectric transformer with magnetization.

The device is a structure made in the form of a magnetoelectric capacitor included in the input circuit, the dielectric of which is a three-dimensional magnetostrictive piezoelectric composite material in the form of a flat ring 1. Thin metal contacts 2 are applied on the inner and outer surfaces of the ring to supply an input signal. The capacitor dielectric is pre-radially polarized by applying a constant voltage to the capacitor plates. An inductor 3 containing N turns is wound around the capacitor. In addition to the inductor, a capacitor 4 is included.

The device operates as follows: a constant voltage U _bias is applied to the inductor, which creates a bias field in the ring structure. The voltage value is selected so that the generated field corresponds to the maximum value of the magnetoelectric effect. An alternating voltage of frequency f is applied to the input electrodes, which creates mechanical stresses in the piezoelectric phase of the composite. These stresses are transmitted through a mechanical interaction between the components to the magnetostrictive phase, resulting in a change in the magnetization, leading to a change in the magnetic flux penetrating the coil wound on the sample, which leads to the appearance of induction emf, which is removed from the capacitor. The presence of a capacitor allows you to separate the variable output signal U _out and the constant component U _bias , which creates a bias field. This allows you to use the inductor as an output winding, and at the same time as a coil that creates a bias field.

Unlike the prototype, a magnetoelectric ring transformer with magnetization due to the presence of a capacitor in the output circuit allows the inductor to be simultaneously used to create a magnetization field, which leads to an increase in the efficiency of the device.

Thus, the present invention can significantly improve the characteristics of the device and increase the efficiency of the magnetoelectric transformer.

Claims (1)

A magnetizing magnetoelectric ring transformer, which is a structure made in the form of a magnetoelectric capacitor included in the input circuit, whose dielectric is a volume magnetostrictive piezoelectric composite material in the form of a flat ring, on the inner and outer surfaces of which electrodes are applied, and an inductor wound on it, characterized the fact that an additional capacitor is connected to it, from which the output signal is removed, and the coil is inductively It is simultaneously used to create a bias field.