Device for controlling gas flow and admixtures amount in gas wells product

FIELD: gas industry.

SUBSTANCE: device has two piezoceramic detectors of flow pressure pulses, output of first of which is connected to input of synchronizing low frequency amplifier. Output of synchronizing amplifier is connected to input of first active band filter, output of which is connected to first input of scaling amplifier, output of which is connected to input of ADC. ADC output is connected to first input of microprocessor controller. First output of controller is connected to second input of scaling amplifier. Device also has level comparator, pulse generator, second and third active band filters, while controller is made with product parameters recorders. Additionally provided are two-mode filter, switchboard and fourth active band filter. Output of second piezoceramic detector is connected to input of two-mode passive filter, output of which is connected to input of second active band filter. Output of second filter is connected to inputs of, respectively, third and fourth filters, outputs of which are connected to first and second inputs of switchboard, connected to level comparator input. Output of the latter is connected to input of pulse generator, output of which is connected to second input of controller. Second output of controller is connected to third input of switchboard.

EFFECT: higher precision.

2 dwg

 

The present invention relates to the field of gas industry and can be used for measuring the gas flow and the amounts of impurities (sand and vodohranilishnoe mixture) in the production of gas wells.

A device for controlling the flow of components production wells containing piezoelectric sensor pressure pulsation flow, impedance amplifier, three active bandpass filter, scaling amplifier, analog-to-digital Converter, two comparator levels, two of the pulse shaper and the microprocessor controller (patent RF №2151288, E 21 47/ 10, 1998).

The disadvantage of this device is the low immunity, since the presence of one sensor can not distinguish the useful signals at the stage of initial conversion.

Closest to the proposed invention is a device for controlling the flow of components production wells containing two piezoceramic sensor, three matching amplifier, three active bandpass filter, scaling amplifier, two comparator level, the analog-to-digital Converter, two pulse shaper and a microprocessor controller, and a matching amplifier low pass and the first matching amplifier high-pass connected to the first piezoelectric sensor pressure pulsation (gas and is ESOC), and the second impedance amplifier high-pass connected to the second sensor (VGPS) (patent RF №2148168, E 21 In 47/10, 1998).

The disadvantage of this device is the low immunity of the gas channels and sand as useful signals are received from one sensor, resulting in reduced accuracy of the control of gas flow.

Object of the present invention is to provide a device for simultaneous, separate gas flow measurement, quantities of sand and vodohranilishnoe mixture (VGPS) in production wells with high noise immunity on all three channels at the expense of circuit unification of channels VGPS and the sand and the temporary separation of measurement cycles.

The solution of this problem is achieved that the device containing the first and second piezoelectric sensors pressure pulsation flow, the first of which is connected to the input impedance of the amplifier lower frequencies, the output of which is connected to the input of the first active bandpass filter, the output of which is connected to the first input of the scaling amplifier, the output of which is connected to the input of the analog-to-digital Converter, the output of which is connected to the first input of the microprocessor controller, the first output of which is connected to the second input of the scaling amplifier, the comparator level, the driver impul the owls, microprocessor controller with data recorders products, second and third active bandpass filters according to the invention additionally introduced passive doodly filter, the switch and the fourth active band-pass filter, and the output of the second piezoceramic sensor is connected to the input Domodedovo passive filter, the output of which is connected to the input of the second active bandpass filter, the output of which is connected to the inputs respectively of the third and fourth active bandpass filters whose outputs are connected to first and second inputs of the switch, the output of which is connected to the input of the comparator level, the output of which is connected to the input of the pulse shaper, the output of which is connected to the second input of the microprocessor controller, the second the output of which is connected to the third input of the switch.

The operation of the proposed device is carried out in accordance with dependencies linking the flow of gas from the RMS value of the informative signal, and the amount of sand and vodohranilishnoe mixture to the number of pulses at the output of pulse shaper:

where QGthe gas flow;

KPthe amount of sand;

KVG is the number vodohranilishnoe mixture;

G1and G2- the RMS value of the signal is informative in the frequency bands;

S1the number of pulses at the output of the shaper pulses during the switching of the channel sand;

S2the number of pulses at the output of the shaper pulses during the switching channel VGPS;

A, b, C are coefficients determined at the stage of calibration.

M is the number of measurement cycles;

To the gain of the scaling amplifier;

Xi- the instantaneous value of the signal information bandwidth.

A block diagram of a device for controlling gas flow and the amount of impurities in the product gas wells shown in figure 1. The device consists of first and second piezoelectric sensors, respectively, 1 and 2, the passive Domodedovo filter 3, the matching amplifier low pass 4, the first, second, third and fourth active bandpass filters, respectively 5, 6, 7 and 8, managed by the scaling amplifier 9, an analog-to-digital Converter 10, a switch 11, a comparator 12, the pulse shaper 13, as well as microprocessor-based controller 14, a display 15, a keyboard 16 and a data recorders products 17.

The device operates as follows.

When forming to the signals "gas consumption" is used the first piezoelectric sensor 1, and when forming the channel VGPS" and "sand" is the second piezoelectric sensor 2. This ensures efficient separation informative low-frequency and high-frequency signals of the channels, respectively, "gas flow" and "sand" with "VGPC" on the stage of the primary conversion of pressure pulsations into an electric signal.

The signal from the first piezoelectric sensor 1 is supplied to the matching amplifier bass 4, which serves to amplify the signal in the corresponding informative low-frequency range. The signal from the matching amplifier bass 4 is supplied to the first active band-pass filter 6, which generates informative bandwidth of the channel "gas flow". He selects and amplifies the signal with frequency components in the range from tens to hundreds of Hertz. Output active bandpass filter 6, the signal at the first input of the scaling amplifier 9, the optimal gain which is set automatically by the microprocessor-based controller 14, the output of which is connected to the second input of the scaling amplifier 9. The output of the scaling amplifier connected to the input of analog-to-digital Converter 10, the output of which the signal at the first input (serial digital input) microprocessor controller 14. Microprocessor controller performs the calculation with the availa able scientific C with algorithm of functioning, and at the end of the measurements obtained value is indicated on the digital display 15.

The formation of the information signals of the channels of the "sand" and "VGPC" is implemented as follows. The output signal of the second piezoelectric sensor 2 is fed to a passive doodly filter 3, which allocates the signals with frequency components in the range of greatest impact parameters "sand" and "VGPC". The outputs of the passive Domodedovo filter 3 is supplied to the second active unimodal band-pass filter 5, which selects and amplifies the signals in the corresponding frequency range. The signal from the active bandpass filter 5 is fed to the inputs of the third and fourth active bandpass filters, respectively 7 and 8, which divide the signals of channels "VGPC" and "sand". Selected and amplified signals of these channels are received at first and second inputs of the switch 11, the time shift channels "sand" and "VGPC" is set to a microprocessor-based controller 14. The signal from the switch goes to the comparator 12. The threshold comparator level is configured certainly higher than the noise level. When the useful signal with an amplitude above the threshold level, the comparator level is triggered and starts the pulse shaper 13. The total number of pulses can be judged on the number of collisions of particles of sand and the GPS sensor. The pulses from the output of the pulse shaper 13 is received on the second input (external interrupt) microprocessor controller 14. After appropriate processing in a microprocessor-based controller, the obtained values are indicated on the digital display 15. The keyboard 16 is used to input parameters of the measurement process. Registrars of product parameters 17 are designed to store the resulting values of gas consumption and amounts of impurities.

The algorithm for the microprocessor-based controller 17 shown in figure 2. It contains the following basic operations.

On the first login:

1 - start;

2 - the self-test routine;

3 - the initialization routine of system resources;

4 - keyboard input the number of cycles of dimension M;

5 - reset the drive channel of the gas flow, the amount of sand and the amount VGPS;

6 - initializing gain For scaling amplifier;

7 - initialization time of the switching channels "VGPC" and "sand";

8 - reading from ADC instantaneous values of the signal Xiin informative frequency band;

9 - the accumulation of the sum (Xi/K)2;

10 is a subroutine To calculate the optimal;

11 is output To the output of microprocessor controller;

12 - check the end of the last measuring cycle;

13 - calculation of the RMS value of G;

14 - ycycline gas flow, the amount of sand and the amount VGPS by the formulas (1), (2) and (3), respectively;

15 o QG, KPand KWGPSindication;

16 - the end.

On the second input:

17 - start routine interrupt pulse shaper;

18 - reset the drive pulses;

19 - increase per unit of drive pulses;

20 - check the end time of switching;

21 - zapping "VGPC" and "sand";

22 - return to main program.

Device for controlling gas flow and the amount of impurities in the product gas wells containing the first and second piezoelectric sensors pressure pulsation flow, the first of which is connected to the input impedance of the amplifier lower frequencies, the output of which is connected to the input of the first active bandpass filter, the output of which is connected to the first input of the scaling amplifier, the output of which is connected to the input of the analog-to-digital Converter, the output of which is connected to the first input of the microprocessor controller, the first output of which is connected to the second input of the scaling amplifier, the comparator level, the pulse shaper, a microprocessor controller with data recorders products, second and third active bandpass filters, characterized in that it additionally introduced the passive vododilny filter, the switch and the fourth active band-pass filter, and the output of the second piezoceramic sensor is connected to the input Domodedovo passive filter, the output of which is connected to the input of the second active bandpass filter, the output of which is connected to the inputs respectively of the third and fourth active bandpass filters whose outputs are connected to first and second inputs of the switch, the output of which is connected to the input of the comparator level, the output of which is connected to the input of the pulse shaper, the output of which is connected to the second input of the microprocessor controller, the second output of which is connected to the third input of the switch.



 

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