RU2565527C1 - Method of transmitting data through air gap and device therefor - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: method employs as the excitation signal of inductively coupled circuits short pulses, having positive polarity for example, obtained by differentiating initial code data transmissions. The device includes, on a rotating part, a repeater, a differentiating circuit, a limiter, for negative pulses for example, a former, first circuit of inductively coupled circuits and a secondary circuit thereof on a fixed part. The input of the repeater is the input of the device and its output is connected through the differentiating circuit and the limiter to the input of the former, the output of which is connected to the primary circuit of inductively coupled circuits, the output of the secondary circuit of which is the output of the device.

EFFECT: low power consumption and shorter duration of generated signals.

2 cl, 3 dwg

Description

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 objects, different types of communication between the rotating and stationary parts of the measuring equipment are used [1].

The most seemingly simple way involves the use of contact current collectors, but the quality of data transmission through such current collectors does not meet the requirements for them in terms of accuracy and reliability, as well as the simplicity and safety of their operation [1].

Contactless 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.

One of the methods of the first group involves the transfer of data using WiFi technology [2] to a distance of several meters. The disadvantages of the method are due to the characteristics of the interaction of the receiver and the signal transmitter. The interference of waves, the influence of external interference significantly reduce the noise immunity of the method, lead to data loss and to a decrease in the declared transmission speed. The method involves the use of traditional elements of the radio channel - modulator, demodulator and the corresponding filter, complicating the channel, introducing additional signal conversion errors and increasing the transmission time of one bit of the data code due to transients that occur in the conversion path.

Another method of the first group for transmitting data through the air gap involves the use of inductive coupling, through which the 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 [3]. The disadvantage of this method is the use of the above-mentioned elements of the radio channel: 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 excluded.

Closest to the proposed method (prototype) is a method of transmitting data through an air gap [1] (p. 17-21), which consists in the fact that the data is transmitted by supplying a short square-wave pulses and the required amplitude from the driver to the primary rotating circuit of inductively coupled circuits (ICC). On the secondary stationary circuit, separated from the rotating air gap, signals are formed that are suitable for deciding what was transmitted in this category of code - “zero” or “unit”.

The disadvantage of this method is the long reaction time of the secondary circuit of the ISK to the exciting effect in the form of a short rectangular pulse coming from the shaper to their primary circuit at the time of transmission of a single discharge of the data code. Thus, the prototype is not fast enough when transmitting bits of a data code, and its speed can be improved when using a different type of exciting signal.

The essence of the proposed method is as follows.

On the rotating part, the initial pulses of the code packets of a rectangular shape are matched by the repeater of the code packets with the input of the differentiating circuit to which they arrive. Pulses of, for example, negative polarity, are excluded from the sequence of different-polarity short pulses with an exponential decay obtained by differentiation, using a limiter. From pulses of another, for example, positive polarity, a driver generates a primary circuit excitation signal inductively coupled to a secondary circuit located on the fixed part and separated by an air gap. A short-duration exciting signal, having an exponential decay and a sufficient amplitude, will cause a signal on the secondary circuit that allows you to decide on the value of the transmitted code bit.

The proposed method allows to eliminate the disadvantage of the known method, namely, to reduce the reaction time of the ISK to the stimulating effect, formed differently than in the known method, and thereby increase the data transfer rate.

The principle of achieving the above technical result by performing the above actions with a signal that controls the operation of the pulse exciter signal driver for the primary circuit of the ICD is illustrated by figures 1 and 2, which show the diagrams of the signals generated when transmitting bits of the data code through the air gap.

In FIG. 1, a shows a short rectangular pulse used in the prototype to control the driver of the exciting effect supplied to the primary circuit of the ISK. The shaper repeats this pulse in shape, amplifying it in power. In FIG. 1b shows the signal generated at the output of the stationary circuit of the ISK in response to a short exciting rectangular pulse of the driver. The signal has positive and negative half-waves. In stationary equipment it is possible, for example, to cut off the negative half-wave with a diode, and use the positive half-wave to decide on the value of the transmitted code discharge. However, until the second half-wave of the signal at the output of the ICD caused by the exciting pulse corresponding to a single discharge of the code ends, it is impossible to supply the next exciting pulse. You should wait until the end of the transient process at the output of the ISK, caused by a short exciting rectangular pulse.

In the proposed method, on the rotating part, the initial rectangular signal shown in FIG. 1a, they are amplified by the power of a repeater of code packets and differentiated. A pulse, for example of positive polarity, obtained by differentiation — FIG. 2a, the primary loop of the ISK is fed to the driver of the pulse excitation signal, which repeats it in shape and excites the received pulse with an exponential decay (hereinafter, for brevity, an exponential pulse). The pulse obtained during differentiation of another, for example, negative polarity, is cut off by the limiter. On the fixed part at the output of the secondary circuit of the ISK, separated by an air gap from the primary circuit, under the influence of a positive exponential pulse, the signal shown in FIG. 2b. 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, then this means that a unit was transmitted in this category of the code, and in its absence, zero.

In FIG. Figure 2c shows the dependences of the duration of the ISK output signal upon excitation by a rectangular pulse, τg (curve 1) and exponential pulse, τge (curve 2), on the duration τ of the exciting action for a fixed k = 0.5. The dependences indicate that excitation of the ICS by exponential pulses reduces the reaction time of the ICS and thereby allows to increase the data rate through the air gap. For other values of the coefficient of coupling between the contours, the nature of the presented dependences is preserved.

In FIG. 3 is a structural diagram of a device for implementing the proposed method for transmitting data through the air gap, and in figures 1a, 2a and 2b are diagrams explaining its operation.

To achieve a technical result, which consists in reducing the time for transmitting the bits of the 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 contour by the air gap, is the output of the device, a code parcel repeater is introduced, the input of which is the input of the device, a differentiating circuit which receives the signal from the repeater, and a limiter connected to its output, cutting off the pulse obtained by differentiation, for example, of negative polarity, the output of which 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 repeater 4 of the code packets, a differentiating circuit 5, a limiter 6, a driver 7 of a pulse excitation signal, a primary circuit 8 inductively coupled circuits 10. The stationary part 2 of the device, separated from the rotating part 1 by the air gap 3, contains a secondary circuit 9 of inductively coupled circuits 10.

The input of the device is the input of the repeater 4 code parcels located on the rotating part 1, which receives the bits of the data code. Its output is connected to the input of the differentiating circuit 5, the output of which through the limiter 6 is connected to the driver 7 of the pulse excitation signal, the output of which is connected to the primary circuit 8 of inductively coupled circuits 10. The output of the inductively connected part 2 of the secondary circuit 9 of inductively coupled circuits 10, separated from circuit 8 by the air gap 3, is the output of the device.

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 (Fig. 1A). They are amplified by the repeater 4 of the code messages and are fed to the input of the differentiating circuit 5. From its output, bipolar short pulses with an exponential decay arrive at the limiter 6, which cuts off, for example, a pulse of negative polarity. A pulse of another, for example, positive polarity (Fig. 2a) passes to the input of the driver 7 of the pulse excitation signal, amplifying it in power. The output signal of the shaper acts on the primary circuit 8 of inductively coupled circuits 10, causing at the output of their secondary circuit 9 located on the fixed part 2 and separated from the primary circuit by the air gap 3, a signal (Fig. 2b), by which it is possible to judge the transmitted code discharge .

The technical result of the proposed method and device for its implementation is that a reduction in the transmission time of bits of the data code is achieved by reducing the reaction time of inductively coupled circuits due to the excitation of their primary circuit by an exponential signal.

The symbols for FIG. 3:

1 - rotating part;

2 - fixed part;

3 - air gap;

4 - repeater of code parcels;

5 - differentiating circuit;

6 - limiter;

7 - shaper pulse excitation signal;

8 - primary circuit;

9 - secondary circuit;

10 - inductively coupled circuits.

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. MIC-1100: Operation Manual. - M .: NPP "Mera", 2012. - 27 p.

3. MANNER Sensortelemetrie [Electronic resource]. URL: http: //www.sensortelemetrie.de/de/startseite.html/ (accessed: 08/22/2013).

Claims (2)

1. A method of transmitting data through an air gap, which consists in the fact that rectangular pulses are formed from the code data packets on a rotating part and fed as excitation signals to the primary circuit of inductively coupled circuits in such a way that they are judged by the received signal in their secondary circuit On the transmitted discharge of the code, the secondary circuit of the inductively coupled circuits is separated from their primary circuit by an air gap and is located on the fixed part, characterized in that the code packages amplify the power They differentiate, limit at zero level one of the components of the signal obtained in this case, for example, negative, and form a signal for excitation of the primary circuit of inductively coupled circuits from its other component, for example, positive. 2. A device for implementing a method for transmitting data through an air gap, comprising on the rotating part a driver of a pulse excitation signal connected to the input of the primary circuit of inductively coupled circuits, on a fixed part separated from the rotating part by an air gap, a secondary circuit of inductively coupled circuits, the output of which is the device output, characterized in that a repeater of code messages, a differentiating circuit and a limiter, for example, is negatively introduced into it on the rotating part x pulse, while the input of the repeater is the input device, its output is connected through a differentiating circuit with a limiter, whose output is connected to the input of the excitation signal generator, the secondary circuit of the reaction inductively coupled circuits which are judged on the transmitted code discharge.

Images