Electric submersible pump rotation monitoring device

Abstract

The utility model discloses an electric submersible pump rotation monitoring device, which comprises an input stage circuit connected with any two of three driving lines of an electric submersible pump, and further comprises a three-operation instrument amplifying circuit, a waveform shaping circuit and an isolation output circuit which are connected in sequence, and a power supply circuit which is respectively connected with the circuits, the input stage circuit divides high voltages of any two driving lines into low voltages and inputs the low voltages into the three-operation instrument amplification circuit; the rotating speed of the submersible motor can be monitored in real time no matter whether the motor is in a driving state or not.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of submersible pump detection circuit, especially relates to a submersible electric pump rotation monitoring device. BACKGROUND

[0002] According to different oil and gas environments such as strata, crude oil viscosity and underground pressure, the petroleum exploitation industry also corresponds to various different collection methods, and the submersible electric pump is a kind of artificial lifting oil production method, i.e. electric submersible pump oil production, which is lifted to the ground by the electric submersible motor driven electric submersible multistage centrifugal pump.The electric submersible pump system includes three parts of downhole unit, ground control and power transmission.The downhole unit mainly has electric submersible multistage centrifugal pump, submersible electric motor and submersible electric motor protector.The electric submersible pump cable is used to send the ground power to the downhole, and the power is delivered to the submersible electric motor through the submersible electric motor protector (to prevent well fluid from entering the motor) to drive the electric submersible multistage centrifugal pump.

[0003] When the submersible electric pump stops, the crude oil existing in the pipeline will flow back to the oil well under the action of gravity, and the submersible electric pump and the submersible motor will rotate reversely in the backflow process.If the motor is started again during reverse rotation, a large impact torque will be generated on the equipment, the driver protection will be tripped at least, and the submersible electric pump assembly will be damaged at most, and a safety production accident will occur.As the backflow time of the backflow crude oil cannot be judged, the current method to avoid this problem is to prohibit starting immediately after stopping, and to start after a period of time.According to different site conditions, the site operator will roughly formulate an absolutely safe interval starting time, and sometimes the interval between two starts can be as long as several hours, which greatly reduces the production efficiency. UTILITY MODEL CONTENTS

[0004] Therefore, the utility model aims at providing a submersible electric pump rotation monitoring device, which can monitor the rotation speed of the submersible motor in real time whether the motor is in the driving state or not.

[0005] In order to achieve the above-mentioned purpose, the utility model provides a submersible electric pump rotation monitoring device, which comprises an input stage circuit connected with any two of three driving lines of the submersible electric pump, and further comprises three operational instrument amplification circuits, a waveform shaping circuit and an isolation output circuit connected in sequence, and a power circuit connected with the above-mentioned circuits respectively; the input stage circuit inputs the low voltage obtained by dividing the high voltage of any two driving lines into the three operational instrument amplification circuits;

[0006] The three operational instrument amplification circuits comprise a first amplifier, a second amplifier and a differential amplifier; the positive phase input end of the first amplifier and the second amplifier is connected with the output signal of the input stage circuit, and the opposite phase input end and the output end are connected, wherein the output end of the first amplifier is connected with the opposite phase input end of the differential amplifier, and the output end of the second amplifier is connected with the positive phase input end of the differential amplifier.

[0007] Further preferably, the input stage circuit comprises a high-voltage voltage dividing part, a differential filter part and a limiting protection part; the high-voltage voltage dividing part comprises a first resistor, a fifth resistor, a sixth resistor and a second resistor connected in series in turn and connected with the driving line of the electric submersible pump; the differential filter part comprises a third resistor, a third capacitor and a fourth resistor connected in series in turn; the differential filter part is connected in parallel between the fifth resistor and the sixth resistor after being connected in series; the limiting protection part comprises a first diode and a second diode; the anode of the first diode and the cathode of the second diode are both connected with one end of the third capacitor, the cathode of the first diode is connected with the anode of the second diode, and the other end of the third capacitor is connected with the second diode.

[0008] Further preferably, the waveform shaping circuit adopts an operational amplifier connected with a matching resistor to form a hysteresis comparator.

[0009] Further preferably, the isolation output circuit comprises an isolation optocoupler and a first triode; the anode of the diode of the isolation optocoupler is connected with a voltage V+, one end of an eighth resistor is connected with the cathode of the diode, the other end of the eighth resistor is connected with the output end of the hysteresis comparator, the emitter of the triode in the isolation optocoupler is connected with the base of the first triode, and the emitter of the first triode is connected with the ground.

[0010] Further preferably, the power supply circuit adopts an AC-DC power supply module to convert high-voltage commercial power into direct current and then output a voltage V+ to form a voltage VE after being divided by a resistor.

[0011] The electric submersible pump rotation monitoring device disclosed in the application is isolated among the power supply, the input and the output, thereby isolating mutual interference among the stages and improving the safety of equipment operation. The device can monitor the rotation speed of the electric submersible pump in real time by monitoring the electric signals of any two of the three driving lines of the electric submersible pump, regardless of whether the motor is in a driving state. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 FIG. 1 is a circuit structure schematic diagram of the electric submersible pump rotation monitoring device of the application.

[0013] Figure 2 FIG. 2 is a circuit structure schematic diagram of the input stage circuit of the application.

[0014] Figure 3 FIG. 3 is a circuit structure schematic diagram of the three operational instrument amplifiers of the application.

[0015] Figure 4 FIG. 4 is a circuit structure schematic diagram of the waveform shaping circuit of the application.

[0016] Figure 5 FIG. 5 is a circuit structure schematic diagram of the isolation output circuit of the application. DETAILED DESCRIPTION

[0017] The utility model is further explained in detail through the drawings and the specific implementation.

[0018] As Figure 1 shown, the utility model one aspect embodiment provides a kind of submersible electric pump rotation monitoring device, comprising: the input stage circuit of connecting arbitrary two of three drive lines of submersible electric pump, still comprising three operational instrument amplification circuit, waveform shaping circuit, isolation output circuit connected in turn, and the power supply circuit respectively connected with above-mentioned circuit;The input stage circuit is input into three operational instrument amplification circuit after the high voltage of arbitrary two drive lines is divided into low voltage as low voltage;

[0019] Input stage circuit is composed of high voltage resistance voltage division, filtering and clamping shaping etc.Circuit.Three operational instrument amplification circuit load amplifies the electric signal after voltage division shaping.Waveform shaping circuit is the hysteresis comparator of operational amplifier, has fast action speed and anti-jitter effect etc.Isolation output circuit is used to isolate the signal isolation of load primary side and secondary measurement, improves the stability of overall system, prevents personnel electric shock.Isolation power supply circuit generates positive and negative power supply voltage, and the power supply of load entire system.

[0020] As Figure 3 shown, the three operational instrument amplification circuit includes first amplifier U1C, second amplifier U1D and differential amplifier U1B;The output signal of input stage circuit is connected to the positive input end of first amplifier U1C and second amplifier U1D, and the negative input end is connected with output end, and wherein, the output end of first amplifier U1C is connected to the negative input end of differential amplifier U1B, and the output end of second amplifier U1D is connected to the positive input end of differential amplifier U1B.

[0021] Wherein, three operational instrument amplification circuit load key small signal amplification work.Three operational instrument amplifier has high input impedance, high common-mode rejection ratio, gain accurate adjustable, has stable amplification capacity to different amplitude signal, low noise performance and other excellent characteristics.This means that it has very small load effect to signal source, when being connected with sensor and other output impedance higher signal source, can more accurately pick up weak signal, avoid that the output of signal source occurs greater change due to the access of amplifier, guarantees the integrity and accuracy of signal;It has extremely high signal quality and signal-to-noise ratio simultaneously, can keep stable amplification multiple to different amplitude input signal, can improve the definition and distinguishability of signal.

[0022] As Figure 2The input stage circuit comprises a high-voltage voltage dividing part, a differential filter part and a limiting protection part; the high-voltage voltage dividing part comprises a first resistor R21, a fifth resistor R5, a sixth resistor R6 and a second resistor R22 connected in series with the driving line of the submersible electric pump; the differential filter part comprises a third resistor R3, a third capacitor C3 and a fourth resistor R4 connected in series; the differential filter part is connected in parallel between the fifth resistor R5 and the sixth resistor R6; the limiting protection part comprises a first diode D1 and a second diode D2; the anode of the first diode D1 and the cathode of the second diode D2 are both connected to one end of the third capacitor C3, the cathode of the second diode D2 is connected to the anode of the first diode D1, and the other end of the third capacitor C3 is connected. Figure 2 The input stage circuit, R21, R22, R5 and R6 are high-voltage voltage dividing resistors, which divide the high voltage on the motor driving line into differential low voltage for use by the subsequent circuit; the resistors R3, R4 and the capacitor C3 constitute a filter of the differential circuit, which filters out the line interference; the diode D1 functions as a limiting shaper to protect the subsequent circuit and avoid damage to the subsequent circuit caused by unknown high-voltage pulses.

[0023] Further preferably, the waveform shaping circuit comprises an operational amplifier connected with matching resistors to form a hysteresis comparator.

[0024] The isolation output circuit comprises an isolation optocoupler and a first triode; the anode of the diode of the isolation optocoupler is connected to a voltage V+, the cathode is connected to one end of an eighth resistor, the other end of the eighth resistor is connected to the output end of the hysteresis comparator, the emitter of the triode in the isolation optocoupler is connected to the base of the first triode, and the emitter of the first triode is connected to ground. Figure 4 The upper part of the figure is the shaping circuit, which is realized by a hysteresis comparator formed by an operational amplifier, and has the functions of fast action speed and anti-jitter. The lower part of the figure is the isolation output part, which uses an optocoupler for isolation and outputs after being amplified by a triode.

[0025] The upper-stage signal is filtered by R14 and C4 and reaches the hysteresis comparator formed by the operational amplifier U1A. When the signal reaches the action threshold of the hysteresis comparator, the hysteresis comparator acts, and simultaneously drives the isolation optocoupler U2 through the resistor R18. The isolation optocoupler U2 drives the triode Q1, and the triode outputs a flip. Since the input signal is an alternating current signal, the final output of the circuit is an isolated square wave. The frequency of the square wave is the motor operating frequency. Thus, the rotation of the motor can be monitored.

[0026] Further preferably, the power supply circuit uses an AC-DC power supply module to convert high-voltage commercial power into direct current, and then outputs a voltage V+ which is divided by resistors to form a voltage VE. Figure 5The power supply circuit is provided. High voltage mains enters the AC-DC power module U3 through the fuse F1 and the filter inductor L1, and the U3 outputs a direct current stabilized voltage, which is divided by R1 and Z1 to form positive and negative voltage to supply power to other circuits. Compared with the traditional power frequency transformer scheme, the scheme has many advantages such as small size, light weight, high efficiency, stable output voltage, wide input voltage range and the like. The direct current voltage only uses the resistor R1 and the stabilized diode Z1 to realize the positive and negative power supply, which maximally simplifies the power supply circuit and improves the stability.

[0027] Obviously, the above embodiments are only examples for clearly illustrating, but not limit the embodiments. For those skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, all the embodiments need not and cannot be exhausted. The obvious changes or variations derived therefrom are still within the protection scope of the utility model.

Claims

1. A submersible electric pump rotation monitoring device, characterized in that, include: The input stage circuit, which connects any two of the three drive lines of the submersible electric pump, also includes a three-operation instrument amplifier circuit, a waveform shaping circuit, an isolation output circuit, and a power supply circuit connected in sequence to the above circuits; the input stage circuit divides the high voltage of any two drive lines into a low voltage and inputs it into the three-operation instrument amplifier circuit. The three-operational instrumentation amplifier circuit includes a first amplifier, a second amplifier, and a differential amplifier; the non-inverting input terminals of the first amplifier and the second amplifier are connected to the output signal of the input stage circuit, and the inverting input terminals are connected to the output terminals, wherein the output terminal of the first amplifier is connected to the inverting input terminal of the differential amplifier, and the output terminal of the second amplifier is connected to the non-inverting input terminal of the differential amplifier.

2. The submersible electric pump rotation monitoring device according to claim 1, characterized in that, The input stage circuit includes a high-voltage divider, a differential filter, and a limiting protection section. The high-voltage divider includes a first resistor, a fifth resistor, a sixth resistor, and a second resistor connected in series with the drive line interface of the submersible pump. The differential filter includes a third resistor, a third capacitor, and a fourth resistor connected in series. The differential filter is connected in parallel across the fifth and sixth resistors. The limiting protection section includes a first diode and a second diode. The anode of the first diode and the cathode of the second diode are both connected to one end of the third capacitor, and the cathode is connected to the anode of the second diode and the other end of the third capacitor.

3. The submersible electric pump rotation monitoring device according to claim 1, characterized in that, The waveform shaping circuit uses an operational amplifier connected to a matching resistor to form a hysteresis comparator.

4. The submersible electric pump rotation monitoring device according to claim 1, characterized in that, The isolated output circuit includes an isolation optocoupler and a first transistor; the anode of the diode in the isolation optocoupler is connected to voltage V+, the cathode is connected to one end of an eighth resistor, the other end of the eighth resistor is connected to the output of a hysteresis comparator, the emitter of the transistor in the isolation optocoupler is connected to the base of the first transistor, and the emitter of the first transistor is grounded.

5. The submersible electric pump rotation monitoring device according to claim 1, characterized in that, The power supply circuit uses an AC-DC power module to convert high-voltage mains power into DC power, and outputs a voltage V+, which is then divided by resistors to form a voltage VE.

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