SU1610449A1 - Method of determining parameters of electromechanical transducer - Google Patents

Abstract

The invention relates to measurement technology, radio engineering, geophysics, and can be used, in particular, in studies of magnetoelectric or electrodynamic seismic receivers, loudspeakers, microphones. The aim of the invention is to increase the number of simultaneously determined parameters, increase speed, potential noise immunity and accuracy. The goal is achieved by the fact that an electromechanical transducer is excited by a rectangular current pulse of amplitude I _c and a duration sufficient for damping transients; Array U _{I of} voltage measurement results U (T) compute the values of three sums: S ₁ = * ε U _I

S ₂ = ε / U _I /

S ₃ = ε (U _I ) ² , where I is the measurement number, calculate the natural frequency Ω ₀ and degree β of calm by the formulas β = {1 + ϕ ² [LN (S ₂ + S ₁ / S ₂ -S ₁ ) ] ^-2 } ^- * 099099, ⁵ , Ω ₀ = 4 ^. β ^. S ₃ / S ₁ ^. 1 /? T, then the known value of the inertial mass M of the transducer coefficient K is calculated by _direct conversion formula K _ave = Ω ₀ ^{(M.? T.} S ₁ / I _in) ^{°, 5.} 1 il.

Description

The invention relates to measurement technology, radio engineering, geophysics, and can be used, in particular, in testing magnetoelectric or electrodynamic seismic receivers, loudspeakers, microO (1unov, etc.).

The aim of the invention is to increase the number of simultaneously determined parameters and increase speed.

The goal is achieved by the fact that an electromechanical converter is excited by a rectangular pulse of electric current with amplitude 1d and a duration sufficient to damp the transient process, after the end of the pulse, the process of free damped oscillations is analyzed, and a series of voltage measurements on the outputs of the converter with an interval time 4t, which is chosen sufficiently small compared to the period of the natural frequency Sd) of the converter, according to the results of measurements U, the value of tp is calculated x sum of "x}) rmulam:

t.i S.

(O (2) ± | and; 1;

S,

; &

.y - 1

 but-; ), (3)

P - {- t t - i: rT

Next, using the ratio of the sum of 5 to Sj and the calculated value of D, calculate the value of your own frequency CO5 by the formula

yg one

with „

A-rt -

(five)

mr

S

Using the a priori known inertial mass value m, the conversion factor of the converter is calculated using the formula

) (6) g J- in

In the drawing / shows a block diagram of a device that implements the proposed method.

The drawing indicates: - the converter under study, conventionally shown in the form of an inductor L and a resistance .2 and 3 terminals for connecting the converter; 4 - voltage source; 5 voltage-to-current converter} 6 controlled switch: 7 - analog-to-digital converter ADC; 8 electronic computer (computer); 9 - control unit (CU); 10 full-wave rectifier.

The device works as follows.

In the initial state, the output of converter 1 by means of switch 6 is closed to a common bus. The signal WU 9 switch 6 switch on time t. Converter 1 receives a pulse of excitation current I. The value of the current Tg is chosen from the condition of the converter in the linear region.

At the end of the time tg, the CU 9 starts to generate the Start signals arriving at A1Sh 7 and the computer 8 at a time interval during the entire measurement time.

AllJl 7 converts the voltage U (t) or | u (t) l into code equivalents: II, or.

The computer performs mathematical processing of the received stakes in accordance with the above formulas.

Claims (1)

Invention Formula The method of determining the parameters an electromechanical transducer consisting in exciting a rectangular transducer with a pulse of electric current of known amplitude T-analysis of the transient the process of free damping of the voltage U (t) at the output terminals of the converter coil at the end of the pulse, is distinguished by the fact that, at the same time, the detector has more than one parameter and increased speed, after the excitation pulse is completed, a series of voltage measurements is taken U (t) at the outputs of the converter with the interval of time between them & t and by the results and outputs Uj calculate the sums at S, i. S,. ±, Ui |. S,. (U; where i is the measurement number, the degree in tranquility and the natural frequency of the OED converter are calculated by the formulas: S9 2 f- S ABOUT)., it then, using the known values of the inertial mass m of the converter and the amplitude IJ of the excitation current, calculate the value of the coefficient K (,, p of the converter using the formula K -: l). (2jAtiSi.x5 (- I