RU2106648C1 - Insulation parameters metering device - Google Patents

Abstract

FIELD: measurement technology; measurement of insulation characteristics of substances by means of capacitive or inductive pickup. SUBSTANCE: device has metering circuit set up of vacuum crystal cavity and insulation pickup whose first lead is connected to zero potential bus and to first lead of resistance-to-signal converter whose second lead is connected to first lead of vacuum crystal cavity. Newly introduced in device is reactance unit in the form of variable capacitor or inductance coil for shaping series oscillatory circuit together with insulation pickup tuned to series resonance frequency of vacuum crystal cavity whose second lead is connected through reactance unit to second lead of insulation pickup. Additional reactance unit is introduced and connected to series oscillatory circuit for its detuning due to resonance frequency of vacuum crystal cavity. EFFECT: improved measurement accuracy and speed of response. 2 cl, 1 dwg

Description

 The invention relates to measuring equipment.

 A device for measuring the parameters of dielectrics [1], which contains a measuring chain of a vacuum quartz resonator with a series-connected dielectric sensor, the grounded output of the sensor and the output of the resonator connected to a grounded and potential converter of the equivalent active resistance of the resonator into an electrical signal.

 The disadvantage of this device is the dependence of the sensitivity and measurement accuracy on the parameters of the dielectric sensor. So, for example, with an increase in the capacitance of the sensor, the sensitivity of the device decreases sharply, lowering the accuracy of the application, and for certain parameters of the dielectric sensor, the use of the device is not possible.

 The aim of the invention is to improve the measurement accuracy by increasing the sensitivity of the device regardless of the parameters of the dielectric sensor, as well as improving performance.

 The drawing shows a structural diagram of a device.

 A device for measuring the parameters of dielectrics contains a measuring chain of a vacuum quartz resonator 1 and a dielectric sensor 2, the first output of which is connected to the zero potential bus and the first output of the resistance to electric signal converter 3, the second output of which is connected to the first output of the vacuum quartz resonator 1. To the measurement a reactive resistance element is introduced in the form of a variable capacitor 4 or inductor 5, forming a dielectric sensor com 2 is a serial oscillatory circuit 6 tuned to the frequency of the serial resonance of a quartz resonator 1, the second output of which is connected through the reactance element 4 and 5 to the second output of the dielectric sensor 2. An additional reactance element 7 is introduced into the measuring chain, connected in series to the oscillation contact 6 using switch 8 for a small detuning of the oscillatory circuit from the frequency of the series resonance of the quartz resonator. The resistance converter contains a pointer 9.

 The device operates as follows.

где
R_о - общее электрическое сопротивление колебательного контура;
R - активная составляющая комплексного сопротивления контура;
ω - круговая частота последовательного резонанса кварцевого резонатора;
L, C - индуктивность и емкость колебательного контура;
R_g - эквивалентное активное сопротивление кварцевого резонатора, которое преобразуется преобразователем сопротивления 3 в электрический сигнал, который фиксируется указателем 9.The oscillation circuit 6 is tuned to the frequency of the series resonance of the quartz resonator 1 using the variables of the capacitor 4 or inductor 5 by finding the minimum value of the pointer 9. When the controlled parameter acting on the dielectric sensor 2 changes, the total resistance of the measuring chain changes in accordance with the expression

Where
R _about - the total electrical resistance of the oscillatory circuit;
R is the active component of the complex resistance of the circuit;
ω is the circular frequency of the series resonance of the quartz resonator;
L, C - inductance and capacitance of the oscillatory circuit;
R _g is the equivalent active resistance of the quartz resonator, which is converted by a resistance converter 3 into an electrical signal, which is fixed by pointer 9.

 The pointer scale can be graduated in units of a controlled value (humidity, concentration, level, etc.). To increase the sensitivity of the device after tuning the oscillatory circuit to the frequency of the serial resonance using the switch 8, an additional reactance element 7 is connected to the oscillatory circuit 6 to provide a small detuning of the frequency of circuit 2 from the resonant frequency of the quartz resonator 1, where the sensitivity to changes in the parameters of the oscillatory circuit is maximum, and device conversion characteristic is linear.

Claims (2)

 1. A device for measuring the parameters of dielectrics, containing a measuring chain of a vacuum quartz resonator and a dielectric sensor, the first output of which is connected to a bus of zero potential and the first output of the resistance to electric signal converter, the second output of which is connected to the first output of the vacuum quartz resonator, characterized in that a reactance element is introduced into it, made in the form of variables of a capacitor or inductor with the possibility of forming a combination It is identical with a dielectric sensor of a series oscillatory circuit tuned to the frequency of a series resonance of a vacuum quartz resonator, the second terminal of which is connected through the reactance element to the second terminal of the dielectric sensor.  2. The device according to claim 1, characterized in that an additional reactance element is inserted into it, connected to a series oscillatory circuit with the possibility of detuning the oscillatory circuit from the resonant frequency of the vacuum quartz resonator.