LT6329B - Piezoelectric generator of high frequency vibrations for converting into electricity - Google Patents

Abstract

The invention relates to devices for electric power generation using the piezoelectric effect. The invention aims – to increase by vibratory piezoelectric electrical energy generator generated voltage, wherein high frequency transducer is excited by high frequency or random signal. The said purpose is achieved when the high-frequency vibration generator piezoelectric conversion into electrical energy comprises in a frame arranged rectangular piezoelectric bracket shaped transducer and a rigid support, the piezoelectric rectangular bracket-type base cross-section at the bottom and the top is oval-rimmed length L brackets instead of 0,24L, piezoelectric layers are cover the upper heat-sink base, other than the cross-sections of the bold, and rigid support to which excited transducer struck, is attached to in the horizontal plane at distance of 0,78 L from the fixing place of transducer base.

Description

Technical field

BACKGROUND OF THE INVENTION The present invention relates to the field of devices, in particular to devices for generating electric power using piezoelectric effect.

It is an energy harvesting (piezoelectric) electric power generator. When the oscillator excites the generator, the piezoelectric layers of the generator are deformed and generate electricity.

State of the art

There is a known vibratory oscillator consisting of a piezoelectric transducer embedded in a shoe pad connected to an electric power processing and storage circuit. The piezo element of the generator is triggered when a person starts to walk; when the level of force generated by the human foot reaches a certain level, the piezoelectric bracket-type transducer starts to vibrate by impacting the rigid support, and the piezo-layer of the transducer is deformed to generate electricity (see US20060021261 A1, A43 B5 / 10, H02N 2 / 18,2006).

There is a known vibratory oscillator consisting of a piezoelectric double-layer boom-type transducer (with concentrated mass attached to the end of the boom) and a rigid support to which the excited transducer impacts (see KH Mak et al., "Performance of a cantilever piezoelectric energy harvester imapacting a bump stop"). , Journal fo Sound and Vibration, 330, 2011).

The clamp of the given device has a constant cross-section and is not adapted for the conversion of RF oscillations into electricity. The device's native frequencies are controlled by the addition of a concentrated mass at the end of the bracket, which limits the device's minimization capabilities. The location of the support impacted by the transducer is random, and no higher vibration shapes are used to generate energy.

The essence of the invention

The object of the invention is to increase the voltage generated by a vibrating piezoelectric power generator by excitation of the converter by a high frequency or a random signal.

The stated objective is achieved by the fact that in the piezoelectric generator for the conversion of RF frequencies into electricity consisting of a piezoelectric rectangular beam type transducer and a rigid support mounted in a housing, the tops of the transducer base, with the exception of the bore cross section, are covered with layers, and the rigid support impacted by the transducer is mounted in the horizontal plane of the housing at a distance of 0.78 L from the transducer base anchorage.

Brief description of the drawings

The invention is explained in the figures.

FIG. Principle diagram of piezoelectric generator for the conversion of RF frequencies to electricity.

FIG. (a) For piezoelectric transducer optimized for second frequency oscillation, maximum clamp cross-section at x / L = 0.24; (b) Rational design of piezoelectric transducer, with maximum cross-section of the beam at x / L = 0.24.

Piezoelectric generator for converting RF oscillations to electricity consists of a clamp-type piezoelectric transducer 2 embedded in a housing 1, consisting of a rectangular base L of length L, oval bulged at the base and top, except the upper part of the base 3 the bold areas covered with piezoelectric layers 4, 5 with electrodes 6, 7, 8, 9 and rigid supports 10 secured at a distance of 0.78 L from the mounting location of the base 3.

Implementation of the invention

The device works as follows.

An excited piezoelectric transducer 2 of rational (Fig. 2b) geometry consisting of a substrate 3 and piezoelectric layers 4, 5, uniformly coated on both sides with electrodes 6,7,8,9, strikes the rigid support 10 embodied in the second oscillating unit of the transducer 2. at 0.78L. In the deformable piezoelectric layers 4.5 of the converter 2, a potential difference occurs, i.e., the voltage transmitted to the electrical circuit.

The optimal geometry configurations of the base 3 of the piezoelectric converter 2 are determined by the following objective function:

Φ (ϊ4) = minpa + A ₂ + ... + A _m ) where A, - is the cross section of the system components / = 1, 2, m. Constraints of the nonlinear programming method are described by the following inequalities.

f _m (A) = lA _m / Ai <0, = l-ω / ω * <0, where ω * is the set system vibration frequency.

By applying the gradient projection states in space, the optimum geometrical configuration of the piezoelectric power generator for the second reduced eigenfrequency was obtained (Fig. 2, a). The maximum cross-section of this configuration is 0.24L from the anchorage point. Since such a geometric configuration of the piezoelectric transducer is difficult to fabricate and it is difficult to form a layer of piezoelectric material on the basis of such a configuration, the system is rationalized as shown (Fig. 2, b). When a rational design strikes a rigid support at a 0.78L second-oscillation junction, higher oscillator shapes can be excited and used to increase the oscillator-generated voltages.

Industrial applicability

Compared to the prototype, the new set of structural elements allows the piezoelectric power generator to be distributed in a distributed parameter system and to excite the higher forms of the operating inverter oscillations independently of the external inverter, which makes it possible to increase

Claims (1)

Definition of the Invention Piezoelectric generator for converting high frequency oscillations to electricity, consisting of a piezoelectric rectangular beam type transducer and a rigid support in a housing, characterized in that the base of the piezoelectric rectangular beam type transducer at the bottom and at the top L0 is oval, the transverse base of the transducer is covered, except for the position of the transverse cross-section, and the rigid support impacted by the transducer is mounted in the horizontal plane of the housing at a distance of 0.78 L from the transverse location of the transducer base.