CN-122014174-A - Temperature control method, equipment and medium for electric submersible screw pump of thick oil well

CN122014174ACN 122014174 ACN122014174 ACN 122014174ACN-122014174-A

Abstract

The application discloses a temperature control method, equipment and medium of an electric submersible screw pump for a thick oil well, wherein the method comprises the steps of periodically collecting pressure data of fluid at the bottom of the electric submersible screw pump and current data of a motor under the electric submersible screw pump; the method comprises the steps of carrying out pressure characteristic identification on a liquid supply state corresponding to an electric submersible screw pump to determine a first feedforward compensation control signal, carrying out load characteristic identification on the electric submersible screw pump according to current data to determine a second feedforward compensation control signal, carrying out partition feedback correction on the rotating speed of a motor based on real-time temperature data to obtain the first electric submersible screw pump rotating speed control signal, and carrying out feedforward compensation on the first electric submersible screw pump rotating speed control signal based on the first feedforward compensation control signal and/or the second feedforward compensation control signal to obtain the second electric submersible screw pump rotating speed control signal. The method solves the technical problem that the existing control method for the motor rotation speed of the electric submersible screw pump under the thickened oil well can not meet the heat dissipation and dynamic balance of output of the motor.

Inventors

ZENG GANG
TAN GUANGXING
JIANG PENG
JIANG JINGXUAN
XIAO SHUMING

Assignees

德仕(西安)油气举升技术有限公司
德仕(西安)石油技术服务有限公司

Dates

Publication Date: 20260512
Application Date: 20260409

Claims (10)

1. A method for controlling the temperature of an electric submersible screw pump for a heavy oil well, the method comprising: periodically acquiring pressure data of fluid at the bottom of the electric submersible screw pump and current data of a motor at the bottom of the electric submersible screw pump; based on the pressure data, performing pressure characteristic identification on the liquid supply state corresponding to the electric submersible screw pump so as to determine a first feedforward compensation control signal; carrying out load characteristic identification on the electric submersible screw pump according to the current data so as to determine a second feedforward compensation control signal; periodically acquiring real-time temperature data of an underground motor of the submersible screw pump, and carrying out partition feedback correction on the rotating speed of the motor based on the real-time temperature data to obtain a rotating speed control signal of the first submersible screw pump; and performing feedforward compensation on the first electric submersible screw pump rotating speed control signal based on the first feedforward compensation control signal and/or the second feedforward compensation control signal so as to obtain a second electric submersible screw pump rotating speed control signal.
2. The method for controlling the temperature of the electric submersible screw pump for the thick oil well according to claim 1, wherein the pressure data of the fluid at the bottom of the electric submersible screw pump and the current data of the electric submersible screw pump motor are periodically acquired, and the method specifically comprises the following steps: Periodically collecting static pressure parameters and dynamic pressure parameters of the well bottom fluid of the electric submersible screw pump, and performing low-pass filtering treatment on the static pressure parameters and the dynamic pressure parameters to obtain the pressure data; And periodically collecting current signals of the underground motor of the submersible screw pump, and carrying out moving average filtering processing on the current signals to obtain the current data.
3. The method for controlling the temperature of an electric submersible screw pump for a heavy oil well according to claim 1, wherein based on the pressure data, performing pressure characteristic recognition on a liquid supply state corresponding to the electric submersible screw pump to determine a first feedforward compensation control signal, specifically comprising: Calculating a pressure change rate corresponding to the pressure data, and judging a pressure change threshold value of the pressure change rate to determine the liquid supply state, wherein the liquid supply state comprises a liquid shortage state and a pump blockage state; under the condition that the liquid supply state is the liquid shortage, based on the pressure change rate, matching a corresponding rotating speed adjustment curve, and determining a liquid shortage compensation control signal corresponding to the electric submersible screw pump according to the rotating speed adjustment curve; Under the condition that the liquid supply state is the pump blockage, the motor rotating speed of the electric submersible screw pump is increased through a preset step length, so that pressure feedback data during the motor rotating speed increasing period are obtained; judging the pressure change trend of the pressure feedback data, and performing overload protection on the electric submersible screw pump under the condition that the pressure change trend is rising; And under the condition that the pressure change trend is reduced, the motor rotating speed of the electric submersible screw pump is increased through the step length until the pressure feedback data reach a preset normal threshold value, and the first feedforward compensation control signal is determined.
4. The method for controlling the temperature of an electric submersible screw pump for a heavy oil well according to claim 1, wherein the load characteristic identification is performed on the electric submersible screw pump according to the current data to determine a second feedforward compensation control signal, specifically comprising: Calculating the current standard deviation of the current data in a preset time window, and detecting the fluctuation abnormal state of the current standard deviation to determine that the electric submersible screw pump passes through an intermittent thick oil section, wherein the fluctuation abnormal state comprises that the current fluctuation amplitude is increased and the fluctuation frequency is low; under the condition that the electric submersible screw pump passes through an intermittent thick oil section, the lowest rotating speed threshold of a motor of the electric submersible screw pump is increased until the fluctuation abnormality is eliminated, and a rotating speed threshold control compensation signal is obtained; Detecting a current overload state of the current data, and reducing the motor rotating speed of the electric submersible screw pump through a preset step length based on the current overload state so as to obtain current feedback data during the period of reducing the motor rotating speed; Judging a current change trend corresponding to the current feedback data, and performing overload protection on the electric submersible screw pump under the condition that the current change trend is rising; under the condition that the current change trend is reduced, reducing the motor rotating speed of the electric submersible screw pump through the step length until the current feedback data reach a preset normal threshold value, and determining a current feedback compensation signal; And determining the second feedforward compensation control signal according to the rotating speed threshold control compensation signal and the current feedback compensation signal.
5. The method for controlling the temperature of the electric submersible screw pump for the heavy oil well according to claim 1, wherein the method is characterized in that based on the real-time temperature data, the motor rotation speed is subjected to zone feedback correction to obtain a first electric submersible screw pump rotation speed control signal, and specifically comprises the following steps: The real-time temperature data is subjected to feedback partitioning to determine a correction threshold corresponding to the real-time temperature data, wherein the correction threshold comprises a target temperature and an alarm temperature; under the condition that the real-time temperature data is smaller than or equal to the target temperature, the output frequency of a frequency converter of the electric submersible screw pump is increased through a preset step length until a preset wellhead yield target is reached, and a first threshold rotating speed control signal of the electric submersible screw pump is determined; under the condition that the real-time temperature data is greater than or equal to the warning temperature, overload protection is carried out on the electric submersible screw pump; calculating a temperature difference value between the real-time temperature data and the target temperature and calculating an output item corresponding to a PID controller of the electric submersible screw pump based on the temperature difference value under the condition that the real-time temperature data is larger than the target temperature and the real-time temperature data is smaller than the warning temperature, wherein the output item comprises a proportion item, an integral item and a differential item; And superposing the output item with the current rotating speed of the electric submersible screw pump to obtain the rotating speed control signal of the first electric submersible screw pump.
6. The method for controlling the temperature of the electric submersible screw pump for the heavy oil well according to claim 5, wherein based on the temperature difference value, calculating an output term corresponding to a PID controller of the electric submersible screw pump specifically comprises: determining the proportional term through proportional gain processing based on the temperature difference value; calculating an integral value corresponding to the temperature difference value according to a preset integral coefficient to obtain an integral term; And calculating a differential value corresponding to the temperature difference based on a preset differential coefficient, and determining the differential term.
7. The method for controlling the temperature of the electric submersible screw pump for the heavy oil well according to claim 1, wherein the feedforward compensation is performed on the first electric submersible screw pump rotating speed control signal based on the first feedforward compensation control signal and/or the second feedforward compensation control signal so as to obtain a second electric submersible screw pump rotating speed control signal, specifically comprising: Superposing the first feedforward compensation control signal and/or the second feedforward compensation control signal with the first electric submersible screw pump rotating speed control signal to obtain a feedforward compensation rotating speed control signal; And carrying out rotation speed limiting constraint on the feedforward compensation rotation speed control signal to obtain a second electric submersible screw pump rotation speed control signal.
8. The method according to claim 1, wherein after feedforward compensating the first electric submersible screw pump rotational speed control signal based on the first feedforward compensation control signal and/or the second feedforward compensation control signal to obtain a second electric submersible screw pump rotational speed control signal, the method further comprises: And sending the second electric submersible screw pump rotating speed control signal to a control end of the electric submersible screw pump, and executing the second electric submersible screw pump rotating speed control signal through the control end to obtain rotating speed update data of the electric submersible screw pump.
9. An electric submersible screw pump temperature control apparatus for a heavy oil well, the apparatus comprising: At least one processor; And a memory communicatively coupled to the at least one processor; Wherein the memory stores instructions executable by the at least one processor to enable the at least one processor to implement an electric submersible screw pump temperature control method for a heavy oil well as claimed in any one of claims 1 to 8.
10. A non-volatile computer storage medium storing computer executable instructions for temperature control of an electric submersible screw pump for a heavy oil well, wherein the computer executable instructions when executed enable a method for temperature control of an electric submersible screw pump for a heavy oil well according to any one of claims 1 to 8.

Description

Temperature control method, equipment and medium for electric submersible screw pump of thick oil well Technical Field The application relates to the technical field of crude oil extraction, in particular to a temperature control method, equipment and medium for an electric submersible screw pump of a thick oil well. Background The thickened oil resource occupies a considerable proportion in the global oil and gas reserves, and when the electric submersible screw pump is adopted to lift the thickened oil, a motor is usually positioned at the lowest end of a unit and is cooled by means of well fluid flowing through the surface of a shell, and the heat dissipation efficiency of the motor directly depends on the speed of fluid flowing through the surface of the motor and the state of the fluid. In actual production of a heavy oil well, the heavy oil has poor flowability, the resistance of flowing from the stratum into the shaft is high, and the flow speed of the fluid in the shaft in a motor area is usually lower than a design critical value. In the prior art, aiming at the exploitation of a thick oil well, a mode of reducing the rotation speed of a pump is generally adopted to match the low liquid supply capacity of a stratum. When the motor speed is reduced, the displacement of the screw pump is reduced, the flow rate of liquid flowing through the surface of the motor is also reduced relatively, and the heat dissipation performance of the motor is further reduced due to the control of the reduction of the motor speed. Namely, when the rotation speed of the motor is reduced, the low liquid yield of the pump body causes insufficient fluid flow rate on the surface of the motor of the pump body, the heat dissipation is further affected by the reduction of the flow rate, and the temperature of the motor is increased during low-rotation-speed operation. Chinese patent CN202411236309.0 discloses an underground intelligent oil extraction pump and a system, wherein a motor drives a screw pump to work according to working parameters indicated by control signals, the screw pump is used for pumping underground oil-containing liquid through an oil pipe or pumping an underground cleaning liquid into the underground through the oil pipe, a ground control cabinet is used for receiving coded data transmitted by a controller, monitoring underground working conditions and controlling the working state of the motor according to monitoring results, and the motor temperature of the screw pump cannot be dynamically controlled in practical application. Therefore, there is a need for a temperature control method of an electric submersible screw pump for a heavy oil well, which can feed back the temperature and fluid flow state of a downhole motor in real time and dynamically adjust the heat dissipation of the motor to balance the heat dissipation and output requirements. Disclosure of Invention The embodiment of the application provides a temperature control method, equipment and medium for an electric submersible screw pump of a thickened oil well, which solve the technical problem that the motor speed control method for the electric submersible screw pump of the thickened oil well in the prior art cannot meet the heat dissipation and dynamic balance of output of a motor. The embodiment of the application provides a temperature control method of an electric submersible screw pump for a heavy oil well, which is characterized by comprising the steps of periodically acquiring pressure data of fluid at the bottom of the electric submersible screw pump and current data of a motor under the electric submersible screw pump, carrying out pressure characteristic identification on a liquid supply state corresponding to the electric submersible screw pump based on the pressure data to determine a first feedforward compensation control signal, carrying out load characteristic identification on the electric submersible screw pump according to the current data to determine a second feedforward compensation control signal, periodically acquiring real-time temperature data of the motor under the electric submersible screw pump, carrying out partition feedback correction on the motor rotating speed based on the real-time temperature data to obtain a first electric submersible screw pump rotating speed control signal, and carrying out feedforward compensation on the first electric submersible screw pump rotating speed control signal based on the first feedforward compensation control signal and/or the second feedforward compensation control signal to obtain a second electric submersible screw pump rotating speed control signal. In one implementation mode of the application, the method comprises periodically collecting pressure data of downhole fluid of the submersible screw pump and current data of an downhole motor of the submersible screw pump, and specifically comprises periodically collecting static pressure parameters and dynamic pressure param