RU2674923C1 - Method and device for transmitting data through the air gap with the use of inductive related circuits excited by an acute-angle pulse - Google Patents

Abstract

FIELD: data processing.SUBSTANCE: invention relates to means for transmitting data through an air gap using inductively coupled circuits excited by an acute-angled impulse, with telemetry measurements from the working members of rotating assemblies and mechanisms. In the method, as the excitation signal of the inductively coupled circuits, an acute-angle pulse is used, generated by a subtracting counter and a digital-to-analog converter. Device contains the device pulse generator on the rotating part, AND element, clock generator, subtracting counter, digital-to-analog converter, driver of the impulse excitation signal, primary circuit of the inductively coupled circuits, and their secondary circuit on the fixed part. Single data code sending transforms all counter bits to a single state and starts a linear reduction of the counter code to zero. Digital-to-analog converter connected to the counter generates an acute-angle pulse that drives the primary circuit through the driver.EFFECT: technical result is to increase the noise immunity of the transmitted data.2 cl, 10 dwg

Description

A method of transmitting data through an air gap using inductively coupled circuits excited by an acute-angled pulse, and a device for its implementation

The invention relates to the field of telemetry, in particular to the transmission of pulsed signals through an air gap, and can be used in systems for transmitting and receiving telemetric information from working bodies of rotating units and mechanisms.

To transmit information from sensors located on rotating units and mechanisms, different communication methods are used between the rotating and stationary parts of the measuring equipment [1].

Modern non-contact methods of communication with rotating equipment can be divided into two large groups. One group includes methods involving the transmission of data over a radio channel by modulating a parameter of a carrier high-frequency signal. Another group includes methods that allow pulsed signals to be transmitted through the air gap.

The methods of the first group are represented by devices that are usually called radio telemetry systems (RTS). RTS can differ from each other in the way of organizing radio communications between the rotating and stationary parts of the system.

In the methods of the first group, inductive coupling between the transmitting and receiving elements of the system is widely used for data transmission through the air gap, through which, for example, a carrier wave with a frequency of 13.56 MHz, modulated by digitized signals from sensors on the rotating part, is received and demodulated in the stationary part measuring equipment [2]. The disadvantage of this method is the use of radio channel elements: modulator, demodulator and filter, which complicate the device, introduce additional errors, slow down the transmission rate of one bit of the data code, and with another method of signal transmission - in pulsed form - can be eliminated. In addition, as noted by the developers of the RTS [2] (p. 24), the radio channel is not perfect in terms of noise immunity. The effect of interference on a low-power radio signal will lead to a distortion of code combinations, which will be detected on the stationary part of the system by well-known cyclic control methods. As a result, the distorted code combination will be excluded from consideration, but instead, it will be necessary to obtain a new data value, and this will lead to a decrease in the system transmission rate and to an increase in the error of signal recovery from its samples.

The methods of the second group are represented by devices in which there is no high-frequency carrier of code data packets transmitted from the rotating part of the system to its stationary part [1], and, as a result, they lack the above-mentioned disadvantages of the RTS. In particular, one of the methods of this group [1] (p. 17-21) assumes that data is transmitted through the air gap by exciting, with rectangular short pulses, the required amplitude of the primary rotating loop of inductively coupled circuits (ICC). On the secondary stationary circuit, separated from the rotating circuit by an air gap, signals are formed that are suitable for deciding what was transmitted in this category of the code - zero or one. The method is simple and reliable, but the signal obtained at its implementation at the ISK output is a superposition of two ISK responses to different-polarity excitation current jumps (respectively, to the leading and trailing edges of a rectangular pulse), and therefore has a longer duration, which can be shortened with another method pulse excitation ISK - using exponential pulses.

Closest to the proposed method (prototype) is a method of transmitting data through an air gap [3], which consists in the fact that the informational code parcels received on the rotating part of the measuring system are fed through a repeater (amplifier parcels in power) to a differentiating circuit, cut off by a limiter of two bipolar pulses of an exponential shape, a pulse of one polarity, for example negative, and a pulse of another polarity, for example positive, is fed to the driver Nogo excitation signal of the primary circuit is inductively coupled circuits. As a result of such excitation of the circuits by a signal of an exponential shape, a short signal is formed at the output of the fixed circuit separated by an air gap from the rotating one, suitable for deciding on the transmitted code discharge value.

The disadvantage of this method (prototype) is the low noise immunity due to the fact that the amplitude of the signals at the output of the coupled circuits formed under the influence of pulses of exponential form exciting the primary circuit of the ICD turns out to be small. You can significantly increase the amplitude of the pulses transmitted through the air gap, if you use a different method of excitation of the coupled circuits, while maintaining the advantage of the prototype - its high speed.

The essence of the proposed method is as follows.

On the rotating part of the measuring system along the leading edge of the rectangular pulse corresponding to a unit in the discharge of the information code, an installation pulse is generated in the unit state of all the bits of the binary counter. As a result of installation, the maximum code 2 ⁿ -1 is entered into the counter, where n is the bit capacity of the counter. If there is a unit in the discharge of the information code, the signals from the clock generator are fed to the subtracting counter input of the counter. Clock pulses sequentially change the counter code from the maximum value to zero. If zero is present in the current bit of the information code, then the counter remains in the zero state. The output of the counter (the outputs of its binary digits) is connected to the input (with the inputs of the corresponding binary digits) of a digital-to-analog converter (DAC) having the same bit depth as the counter. At the output of the DAC, a signal is received with a steep leading edge close to a jump from zero to a maximum value, and a subsequent linear (stepwise) decline to zero. Formed as a result of the described actions, an acute-angled pulse is fed from the output of the DAC to the input of the driver of the pulse excitation signal of the primary circuit of the ISK. Such an acute-angled exciting signal having the required amplitude will cause a signal on the secondary circuit of the ISK, separated from the primary circuit by an air gap, which makes it possible to decide on the value of the transmitted discharge of the information code.

The proposed method allows to eliminate the disadvantage of the known method, namely, to increase the amplitude of the information code signals transmitted through the air gap using the ISK due to their excitation by acute-angled pulses in comparison with the amplitude of the signals obtained in the known method using contour excitation by pulses of exponential form. Therefore, the proposed method improves the noise immunity of data transmission.

The principle of achieving the named technical result due to the implementation of the above actions with a signal that controls the operation of the driver of the pulse excitation signal of the primary circuit of the ISK is illustrated by figures 1 and 2.

In FIG. 1a, an exponential pulse expi is used, which is used in the prototype to control the driver of the exciting action applied to the primary circuit of the ICC in the presence of a unit in the discharge of the information code. The shaper amplifies the signal by power. In FIG. Figure 1b shows the signal ge generated at the output of the stationary circuit of the ISK in response to an impulse of an exponential form shaper. The signal has positive and negative half-waves. In stationary equipment, a decision is made about the value of the transmitted discharge of the code, for example, by one of the threshold processing methods.

In the proposed method, on the rotating part of the system along the leading edge of the pulse corresponding to a single bit of the information code shown in FIG. 2, and the signal kod forms a short pulse of the installation of a rectangular shape — the signal iu shown in FIG. 2, b. This signal sets all the bits of the subtracting counter to a single state, which leads to the formation at the output of the connected digital-to-analog converter (DAC) of a jump in the signal level from zero to the highest value - 1 (the value of the reference signal source), as shown in FIG. 2d for the signal cap. If there is a unit in the discharge of the information code, the signals from the clock pulse generator, that is, the counting pulses, signal out_I shown in FIG. 2, c. With each new counting pulse, the code in the counter decreases by one until it becomes equal to zero, which leads to the formation of a linearly decreasing step-shaped cap signal at the output of the DAC (Fig. 2d). The repetition rate f of the signal from the clock generator depends on the duration τ of the generated excitation pulse and the bit width n of the counter and DAC as follows f = (2 ⁿ -1) / τ. In the figures, τ = 0.45 s, and the bit width n = 3. With increasing bit depth n, the step-shaped signal approaches a linearly decreasing signal. As a result of the described actions, an impulse is formed at the output of the DAC that is close in shape to acute-angled. Such a signal is fed to the driver of the pulse excitation signal of the primary circuit of the ISK. Under its influence on the fixed part of the system, at the output of the secondary circuit of the ISK, separated by the air gap from the primary circuit, the signal g shown in FIG. 2, e. The appearance of this signal indicates its suitability for deciding on the value of the transmitted code bit. If a signal of this kind is detected on the secondary circuit, this means that in this category of the ball code, one is transmitted, in its absence - zero. Comparing the signals at the output of the ISK for different ways of exciting their primary circuit, we can conclude that the amplitude m1r of the first (positive) half-wave of the output signal in the proposed method using excitation by an acute-angled pulse (Fig. 2e) doubles the amplitude m1ge of the first half-wave of the output signal obtained in the prototype (Fig. 1, b), in which the excitation pulse has an exponential shape. In FIG. 1c shows the dependence of the ratio of the amplitudes mentioned above, designated m1r and m1ge, respectively, on the duration τ of the exciting pulse for a fixed value of the coupling coefficient k between the loops, equal to 0.5. In FIG. 1d shows how the ratio of amplitudes depends on the coefficient k for a fixed duration τ equal to 0.45 s. Moreover, the loss in the duration of the output signal in comparison with the prototype is less than 5%. Therefore, the proposed method of transmitting data through the air gap has a higher noise immunity compared to the prototype.

In FIG. 3 is a structural diagram of a device for implementing the proposed method for transmitting data through an air gap using inductively coupled circuits excited by an acute-angled pulse, and FIG. 2 - diagrams explaining his work.

To achieve a technical result, which consists in increasing the noise immunity of transmitting bits of a data code, to a device containing on its rotating part a driver of a pulse excitation signal, the output of which is connected to the primary circuit of inductively coupled circuits, the secondary circuit of which is located on the fixed part of the device and separated from the primary the contour by the air gap, is the output of the device, the pulse shaper of the installation, the element And, the clock generator are introduced on the rotating part pulses, subtracting counter and digital-to-analog converter. The input of the pulse generator of the installation is the input of the device and is connected to one input of the element And, the other input of which is connected to the output of the generator. The output of the shaper is connected to the input of the unit in the single state of the bits of the subtracting counter, the output of which is connected to the input of the digital-to-analog converter. The output of the AND element is connected to the counting input of the subtracting counter. The output of the digital-to-analog converter is connected to the input of the driver of the pulse excitation signal.

A device for implementing the proposed method of transmitting data through the air gap contains a rotating part 1, a fixed part 2 and an air gap 3. The rotating part 1 contains a setup pulse generator 4, an element And 5, a clock pulse generator 6, a subtracting counter 7, a digital-to-analog converter 8, a shaper 9 of the pulse excitation signal, the primary circuit 10 of inductively coupled circuits 12. The stationary part 2 of the device, separated from the rotating part 1 by the air gap 3, contains a secondary circuit 11 of the inductance clearly connected loops 12.

The input of the device is the input of the driver 4 of the installation pulse located on the rotating part 1, which receives the bits of the data code. Its output is connected to the unit input in the single state of the discharges of the counter 7, the output of which is connected to the input of the digital-to-analog converter 8. The counter input of the counter 7 is connected to the output of the And 5 element, one input of which is connected to the input of the device, and the other to the output of the 6-clock generator pulses. The output of the digital-to-analog converter 8 is connected to the input of the pulse excitation signal generator 9, the output of which is connected to the primary circuit 10 of the inductively coupled circuits 12. The output of the inductively coupled secondary circuit 11 of the inductively coupled circuits 12, separated from the primary circuit 10 by the air gap 3, is the output devices.

The device operates as follows. On the rotating part 1 at the input of the device receives the code sending data of a rectangular shape. If the discharge of the information code contains one (Fig. 2, a), then the installation pulse (Fig. 2, b) of all the bits of the subtracting counter 7 in a single state is generated along the leading edge of the code pulse in the shaper 4, and the signals from the clock generator 6 pass through the element And 5 to the input of the counter 7 (Fig. 2, c). At the output of the digital-to-analog converter 8, an acute-angled pulse is generated (Fig. 2d), formed by a jump in the signal from zero to the highest value, followed by a decrease in discrete steps, the size (height) of which is determined by the length of the counter, linearly to zero. Shaper 9 of the pulsed excitation signal of the primary circuit 10 will repeat the acute-angled signal in shape, amplifying it in power, and will cause a reaction to it on the secondary circuit 11 of the ISK 12 (Fig. 2, e), which allows you to decide on the value of the transmitted code discharge.

The technical result of the proposed method for transmitting data through an air gap using inductively coupled circuits and a device for its implementation is that an increase in the noise immunity of transmitting bits of the data code is achieved by increasing the amplitude of the signal transmitted through inductively coupled circuits due to the excitation of their primary circuit by an acute-angled pulse forms.

Literature

1. Measuring systems for rotating units and mechanisms / V.V. Karasev, A.A. Mikheev, G.I. Nechaev; Ed. G.I. Nechaeva. - M .: Energoatomizdat, 1996 .-- 176 p.

2. MANNER Sensortelemetrie [Electronic resource]. URL: http://manner-sensortelemetrie.ru/upload/file/Brochure-production-MANNER (Rus). PDF (accessed date: 10/05/2017).

3. Zilotova M.A., Karasev V.V., Nikolaev A.V. A method of transmitting data through an air gap and a device for its implementation. RF patent No. 2565527. Bull. No. 29, 2015.

METHOD FOR DATA TRANSMISSION THROUGH AIR GAP WITH USE OF INDUCTIVELY CONNECTED CIRCUITS EXCITED BY AN ORGANIZED PULSE, AND A DEVICE FOR ITS IMPLEMENTATION

The symbols for FIG. 3:

1 - rotating part;

2 - fixed part;

3 - air gap;

4 - shaper installation;

5 - element And;

6 - clock generator;

7 - subtracting counter;

8 - digital-to-analog converter;

9 - shaper pulse excitation signal;

10 - primary circuit;

11 - secondary circuit;

12 - inductively coupled circuits.

Claims (2)

1. The method of transmitting data through the air gap using inductively coupled circuits excited by an acute-angled pulse, which consists in the fact that on the rotating part, pulses of a rectangular shape of the information code are used to excite the primary circuit of inductively coupled circuits, the secondary circuit of which is separated from it by an air gap and is located on the fixed part, characterized in that in the presence of a unit in the discharge of the information code they form the impulse of installation in the single state of all the discharge binary counter, and subtracting at its counting input signals fed from the clock pulse generator via a digital to analog converter, which discharges connected with the corresponding bits of the counter, the impulse for initiating the acute forms of the primary circuit is inductively coupled circuits. 2. A device for implementing the method according to claim 1, comprising a driver of a pulse excitation signal connected to the input of the primary circuit of inductively coupled circuits on the rotating part, the secondary circuit of which is located on the fixed part, separated from the rotating part by an air gap, and is the output of the device, characterized the fact that a pulse shaper of the installation, an element And, a clock generator, subtracting the counter and a digital-to-analog converter are introduced into it on the rotating part pulse of the installation pulse and one input of the And element supply pulses of the information code, the second input of the And element is connected to the output of the clock pulse generator, the output of the driver is connected to the input of the unit to the single state of all bits of the subtractive counter, the counting input of which is connected to the output of the And element, the outputs of the counter bits connected to the inputs of the corresponding bits of the digital-to-analog converter, the output of which is connected to the input of the driver of the pulse excitation signal.

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