CN103105593A

CN103105593A - Novel cross-core type sensor

Info

Publication number: CN103105593A
Application number: CN2013100421330A
Authority: CN
Inventors: 程国苗; 季双双; 王敏华
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2013-02-04
Filing date: 2013-02-04
Publication date: 2013-05-15
Anticipated expiration: 2033-02-04
Also published as: CN103105593B

Abstract

The invention relates to a novel cross-core type sensor. A ring-shaped magnetic core of the sensor is arranged in an outer shell, two sets of reversed coils are wound on the magnetic core so as to form a reversed transformer, I and II are the first set of coils, and III and IV are the second set of coils. The end I and the end III of the reversed transformer receive square waves generated from a self-oscillation circuit, the output end II and the output end IV of the reversed transformer are connected with a difference channel, output signals of the difference circuit are sensor collection signals, the II and the IV of the reversed transformer are respectively connected with a first voltage-to-digital converter (VDC) and a second VDC through a current-limiting resistor, the current-limiting resistor is adjustable and capable of changing current in the coils, and therefore square wave frequency is changed, and collection frequency of the sensor mainly depends on turns per coil, namely n. The cross-core type sensor can collect signals of alternating current and direct current, sampling frequency can be adjusted through the turns per coil, and the range of the frequency is from 0 KHZ to dozens of KHZ.

Description

A kind of novel punching sensor

Technical field

The present invention relates to a kind of sensor, particularly a kind of novel punching sensor.

Background technology

Use the method for magnetic saturation punching sensor measurement by the magnetic field in annulus and be a kind of very practical also method of science very.The ultimate principle of this sensor is to utilize Ferrari electromagnetic induction principle and magnetic saturation phenomenon.At first be to utilize the Ferrari electromagnetic induction principle, the annulus of sensor is passed electrified wire in the magnetic field that produces around electrified wire, and the magnetic field that wire produces can be sensed on the coil of transformer.Secondly the transformer on annulus is because the magnetic saturation phenomenon has produced square wave, and magnetic field changed the square-wave waveform of output after advancing transformer coil, can sense signal, make the square-wave waveform distorted, this distortion is regular, that is to say by this rule to measure size of current on electrified wire.Transformer both sides output square wave through difference, obtain a very smart metastable signal.

But the sensor of design can not gather simultaneously to the alternating current-direct current signal now, exchanges or direct current and can only gather, and the frequency that gathers is in addition placed restrictions on.

Summary of the invention

The present invention be directed to sensor and can not propose a kind of novel punching sensor simultaneously to the problem of alternating current-direct current signals collecting, this sensor frequency is adjustable, applied range.

Technical scheme of the present invention is: a kind of novel punching sensor, the toroidal core of sensor is placed in shell, be wound with two groups of reverse windings on magnetic core and form reverse transformer, I, II are first group of coil, III, IV are second group of coil, oppositely the I of transformer, III termination self-maintained circuit produce square wave, oppositely the II of transformer, the output of IV end connect difference channel, the difference channel output signal is the sensor collection signal, oppositely transformer II, IV respectively meet 12VDC by a current-limiting resistance, and current-limiting resistance is adjustable.

Described self-maintained circuit is comprised of two comparers.

Described shell is selected the resistant to elevated temperatures epoxide resin material of antidetonation.

Beneficial effect of the present invention is: the novel punching sensor of the present invention, can gather two kinds of signals of AC and DC, and the frequency of sampling can regulate through row by coil turn, frequency range 0 to tens KHZ.

Description of drawings

Fig. 1 is the novel punching sensor construction of the present invention schematic diagram;

Fig. 2 is the novel punching sensor circuit of the present invention figure;

Fig. 3 is the novel punching sensor of the present invention at the transformer both sides output signal diagram that passes toroidal cores sensor when inner without any electric current;

Fig. 4 is the novel punching sensor of the present invention differentiated oscillogram of sensor output signal process when passing toroidal cores inside without any electric current;

Fig. 5 is the novel punching sensor of the present invention is having electric current to pass the transformer both sides output signal diagram of toroidal cores sensor when inner;

Fig. 6 is the novel punching sensor of the present invention sensor output signal oscillogram through obtaining after difference when having electric current to pass toroidal cores inside.

Embodiment

The toroidal core 2 of sensor is placed in shell 5 as shown in Figure 1, be wound with two groups of reverse windings on magnetic core 2 and form reverse transformer 3, circuit diagram as shown in Figure 2, I, II are first group of coil, III, IV are second group of coil, oppositely transformer 3 I, III connect self-maintained circuit 1, and oppositely the II of transformer, the output of IV end connect difference channel 4, and self-maintained circuit 1 connecting coil produces the reverse transformer II of square wave, IV is exported.The signal of an interchange of difference channel 4 outputs is exactly the signal that sensor collects.The shell 5 resistant to elevated temperatures rings of material epoxy resins of use antidetonation are so its stability is strong, not fragile.

Two groups of reverse transformers 3 that reverse winding forms on the annulus magnetic core 2 of sensor, must combine and to use with self-maintained circuit 1, when transformer I or III generation excitation field, primary side is carried out periodic excitation, make the state that periodically reaches capacity of sensor, voltage drop when saturated, other end II, IV must be overturn and could be produced square wave, so will use the self-maintained circuit that two comparers form.

Oppositely transformer 3 is by the 12VDC power supply, and II, IV all meet 12VDC, and the centre is connected to a current-limiting resistance R45 and R53, the electric current in can regulating winding, thus change square wave frequency.The frequency acquisition of sensor is mainly decided by coil turn n, such as the square wave frequency that sensor produces during 80 circle is 300Hz, and collection period is just more accurate at 0-150Hz so.

The frequency of the drive coil of sensor is

The excitation cycle electric current

, make the magnetic core 2 of the sensor state that periodically reaches capacity, according to the soft magnetic material self-characteristic, the magnetic induction density signal of the magnetic core 2 of sensor is the function about the time that is subjected to the magnetic permeability modulation, the magnetic induction density signal that pumping signal is transferred to

, the pulse signal that inductive coil induces

, N ₂The number of turn and the field coil N of inductive coil ₁=N ₂, the xsect of S magnetic core.The coil ratio of the transformer of sensor is 1:1, and the signal of their output is the signal of a pair of complementation, as shown in Figure 3 at the transformer both sides output signal diagram that passes toroidal cores sensor when inner without any electric current.These two signals waveform such as Fig. 4 through exporting after difference.So just understand very much the sensor final output signal.

Field signal of annular magnet in-core existence when sensor

The time, to the frequency of drive coil be equally

The excitation cycle electric current

, make the sensor magnetic core state that periodically reaches capacity, the magnetic induction signal of magnetic permeability modulation this moment Be in magnetic saturation state and, but inductive impulse signal

Be the incomplementarity symmetric signal, having electric current to pass the transformer both sides output signal diagram of toroidal cores sensor when inner as shown in Figure 5.These two signals are after sensor is subject to the interior influence of magnetic field of magnetic core, the variation of generation.At this moment, if the direction of this externally-applied magnetic field is inwards, waveform upwards moves so, and its effective value increases.If the direction of this externally-applied magnetic field is that outwards waveform is to moving down so, it effectively also increases, and is exactly that direction is different.So this again illustrates to gather and exchanges or direct current signal, because its effective value is all increasing.So just can reach the purpose of measuring the magnetic field size, know afterwards the value of the size of current that needs measurement.Be output signal through the waveform exported after difference as figure as Fig. 6.

Claims

1. novel punching sensor, it is characterized in that, the toroidal core of sensor is placed in shell, is wound with two groups of reverse windings on magnetic core and forms reverse transformer, and I, II are first group of coil, III, IV are second group of coil, oppositely transformer I, III termination self-maintained circuit produce square wave, and oppositely the II of transformer, the output of IV end connect difference channel, and the difference channel output signal is the sensor collection signal, oppositely transformer II, IV respectively meet 12VDC by a current-limiting resistance, and current-limiting resistance is adjustable.

2. novel punching sensor according to claim 1, is characterized in that, described self-maintained circuit is comprised of two comparers.

3. novel punching sensor according to claim 1, is characterized in that, described shell is selected the resistant to elevated temperatures epoxide resin material of antidetonation.