CN1845024A - Frequency conversion control system of long-stroke pumping unit without walking beam - Google Patents
Frequency conversion control system of long-stroke pumping unit without walking beam Download PDFInfo
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- CN1845024A CN1845024A CNA2006100100128A CN200610010012A CN1845024A CN 1845024 A CN1845024 A CN 1845024A CN A2006100100128 A CNA2006100100128 A CN A2006100100128A CN 200610010012 A CN200610010012 A CN 200610010012A CN 1845024 A CN1845024 A CN 1845024A
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Abstract
The invention relates to a frequency-variable control system without beam long stroke pumping unit, which can solve the defects of present pumping unit that complex mechanical steering structure and inability to adjust the stroke or small adjust range. It comprises a motor (1), a programmable logic controller (2), and a frequency converter (3); the output of (2) is connected to the input of (3) to complete the control on the output frequency and phase sequence; the output of (3) is connected to the power source of (1) to control the rotation speed and direction of (1) output axle; the program of (2) comprise a positive accelerate control unit (2-1), a positive uniform speed control unit (2-2), a positive decelerate control unit (2-3), a passive accelerate control unit (2-4), a passive uniform speed control unit (2-5), and a passive decelerate control unit (2-6), to make realize the working processes of (1), as positive accelerate rotation, positive uniform speed rotation, positive decelerate rotation, passive accelerate rotation, passive uniform speed rotation, and passive decelerate rotation.
Description
Technical field
The present invention relates to a kind of electric control system of blue elephant.
Background technology
The kind of oil pumper is very various, walking-beam pumping unit with simple in structure, working service is easy, be suitable for advantage and being widely used such as work under round-the-clock state.But the conventional beam-pumping unit stroke is short, energy consumption is big, type is outmoded, can not adapt to the needs that oil well is taken out technology deeply, has become a big problem of puzzlement field produces and synergism and reducing expenditure.Long-stroke pumping unit without walking beam has overcome that conventional beam-pumping unit and chain type oil pump length of stroke range of adjustment are too small maybe can not regulate, adjust problem such as parameter inconvenience, has the characteristics of long stroke, big load, is the trend of oil pumper development.But the blue elephant great majority adopt the mechanical commutation mode, promptly by the complicated mechanical mode oil pumper suspension point are pumped.This mode complex structure, physical construction is damaged easily, can't regulate stroke or range of adjustment is little.
Summary of the invention
The frequency-changing control system that the purpose of this invention is to provide a kind of long-stroke pumping unit without walking beam, to overcome the blue elephant complex structure of existing employing mechanical commutation mode, physical construction is damaged easily, can't regulate the little defective of stroke or range of adjustment.It comprises motor 1, it also comprises programmable logic controller (PLC) 2 and frequency converter 3, the output terminal of programmable logic controller (PLC) 2 is connected to the input end of frequency converter 3 to finish the control to frequency converter 3 output frequencies and phase sequence, the feedback output end of frequency converter 3 is connected to frequency and the electric current of the analog quantity input end of programmable logic controller (PLC) 2 with feedback inverter, the power output end of frequency converter 3 is connected to sense of rotation and the rotating speed of the power end of motor 1 with control motor 1, the control that program in the programmable logic controller (PLC) 2 realizes motor 1 rotational speed and direction by frequency converter 3, program comprises that forward quickens control module 2-1, with by frequency converter 3 control motor 1 from initial position according to the acceleration operation of appointment to forward position at the uniform velocity; Forward is control module 2-2 at the uniform velocity, at the uniform velocity to travel at the uniform speed to the forward decelerate position according to the speed of appointment the position from forward by frequency converter 3 control motor 1; Forward deceleration control unit 2-3, with by frequency converter 3 control motor 1 from the forward decelerate position according to the acceleration of appointment run slowly to 1 speed moment of motor serve as zero; Oppositely quicken control module 2-4, with by frequency converter 3 control motor 1 from zero velocity according to the acceleration operation of appointment to reverse position at the uniform velocity; Reverse control module 2-5 at the uniform velocity is at the uniform velocity to travel at the uniform speed to reverse decelerate position according to the speed of appointment the position from forward by frequency converter 3 control motor 1; Reverse deceleration control unit 2-6, running slowly to initial position from the acceleration of reverse decelerate position according to appointment by frequency converter 3 control motor 1, and to make motor speed moment be zero.When the present invention worked, the procedure control unit control oil pumper in the programmable logic controller (PLC) 2 was finished upper and lower stroke according to specific curve movement.Because the forward and backward of control motor 1 automatically by the program in the programmable logic controller (PLC) 2 is rotated and acceleration, deceleration, do not use mechanical commutation mechanism, overcome mechanical commutation mode complex structure, the defective that physical construction is damaged has easily realized not having the commutation of impact; In addition by the parameter of program in the programmable logic controller (PLC) 2 is made amendment, can be very easily according to the stroke of field condition change oil pumper, in the unit interval number of strokes and on/the down stroke velocity ratio.Using no walking beam long stroke variable frequency control oil pumper of the present invention, to have a stroke long, do not have mechanical reverse mechanism, do not have the commutation of impact, and stroke, jig frequency, the stroke speed ratio is adjustable up and down, and is energy-conservation, the big and adaptability of carrying lotus by force, the reliability advantages of higher.
Description of drawings
Fig. 1 is a structural representation of the present invention, and Fig. 2 is an electrical block diagram of the present invention, the rotation speed change synoptic diagram of Fig. 3 motor 1 of the present invention.
Embodiment
Embodiment one: specify present embodiment below in conjunction with Fig. 1.Present embodiment is by programmable logic controller (PLC) 2, frequency converter 3 and motor 1 are formed, the output terminal of programmable logic controller (PLC) 2 is connected to the input end of frequency converter 3 to finish the control to frequency converter 3 output frequencies and phase sequence, the feedback output end of frequency converter 3 is connected to frequency and the electric current of the analog quantity input end of programmable logic controller (PLC) 2 with feedback inverter, the power output end of frequency converter 3 is connected to the power end of motor 1 so that the control that the program in the programmable logic controller (PLC) 2 realizes motor 1 rotational speed and direction by frequency converter 3, program comprises that forward quickens control module 2-1, with by frequency converter 3 control motor 1 from initial position according to the acceleration operation of appointment to forward position at the uniform velocity; Forward is control module 2-2 at the uniform velocity, at the uniform velocity to travel at the uniform speed to the forward decelerate position according to the speed of appointment the position from forward by frequency converter 3 control motor 1; Forward deceleration control unit 2-3, with by frequency converter 3 control motor 1 from the forward decelerate position according to the acceleration of appointment run slowly to 1 speed moment of motor serve as zero; Oppositely quicken control module 2-4, with by frequency converter 3 control motor 1 from zero velocity according to the acceleration operation of appointment to reverse position at the uniform velocity; Reverse control module 2-5 at the uniform velocity is at the uniform velocity to travel at the uniform speed to reverse decelerate position according to the speed of appointment the position from forward by frequency converter 3 control motor 1; Reverse deceleration control unit 2-6, running slowly to initial position from the acceleration of reverse decelerate position according to appointment by frequency converter 3 control motor 1, and to make motor speed moment be zero.
It also comprises position switch 4, and program also comprises stroke initial position fix unit 2-8, and position switch 4 is connected the input end of programmable logic controller (PLC) 2, and the starting position that is used to guarantee each stroke cycle of oil pumper is all in the set position of position switch 4.
It also comprises man-machine interface 5, man-machine interface 5 links to each other with the communication port of programmable logic controller (PLC) 2, the various operational factors of given programmable logic controller (PLC) 2, and can revise the parameter that oil pumper moves easily, and show failure diagnosis informations by man-machine interface 5.So be provided with, actual conditions according to oil well, the oil pumper operational factor of setting by the scene (comprising parameters such as stroke, jig frequency, speed ratio) thus the movement locus that calculates suspension point draws the curve movement of motor 1, and the real-time control of conversion device of the output frequency of the analog quantity output port by PLC, thereby allow suspension point speed motor pattern running as requested.Motor 1 drives sucker rod, and sucker rod is moved according to the certain jig frequency and the speed ratio that moves up and down in stroke range, reaches the purpose of efficient oil pumping.This control system can be regulated the operational factor of oil pumper at any time according to field condition, and stroke, jig frequency, up-down stroke time are adjustable continuously in rated range, fast down slowly or upward fast slow point suspension movement speed control mode down in the realization.
Embodiment two: specify present embodiment below in conjunction with Fig. 2.The difference of present embodiment and embodiment one is: it also comprises contactor J1, isolating switch D1, lower stroke switch K1, upper stroke switch K2, forward inching button K3, reverse inching button K4, stop button K5, start button K6, power-on self-test button K7, motor brake solenoid Q and energy consumption resistance R, programmable logic controller (PLC) 2 is selected the MicroLogix1000 micro programmable logic controller of Rockwell Automation for use, the model of frequency converter 3 is Siemens MicroMaster440, the pin L1 of frequency converter 3, pin L2 and pin L3 are connected on the three-phase output end of contactor J1, the three-phase input end of contactor J1 is connected on the three-phase output end of isolating switch D1, the pin DAC2-of frequency converter 3 and pin DAC2+ are connected the pin A3-of programmable logic controller (PLC) 2 and pin A3 respectively to realize current feedback, the pin DAC1-of frequency converter 3 and pin DAC1+ are connected the pin A2-of programmable logic controller (PLC) 2 and pin A2 respectively to realize frequency feedback, the pin DO1/NO of frequency converter 3 connects the pin 11 of programmable logic controller (PLC) 2 to realize the frequency converter failure feedback, the pin 10 of programmable logic controller (PLC) 2 is connected on the output terminal of position switch 4, the pin 9 of programmable logic controller (PLC) 2 is connected to the output terminal of lower stroke switch K1, the input end of lower stroke switch K1 connects 24 volts of high level, the pin 8 of programmable logic controller (PLC) 2 is connected on the output terminal of upper stroke switch K2, the input end of upper stroke switch K2 connects 24 volts of high level, the pin 7 of programmable logic controller (PLC) 2 is connected to the output terminal of forward inching button K3, the input end of forward inching button K3 connects 24 volts of high level, the pin 6 of programmable logic controller (PLC) 2 is connected to the output terminal of reverse inching button K4, oppositely the input end of inching button K4 connects 24 volts of high level, the pin 5 of programmable logic controller (PLC) 2 is connected to the output terminal of stop button K5, the input end of stop button K5 connects 24 volts of high level, the pin 4 of programmable logic controller (PLC) 2 is connected to the output terminal of start button K6, the input end of start button K6 connects 24 volts of high level, the pin 3 of programmable logic controller (PLC) 2 is connected to the output terminal of power-on self-test button K7, the input end of power-on self-test button K7 connects 24 volts of high level, the pin OA-of programmable logic controller (PLC) 2 and pin V+ are connected the pin ADC1-of frequency converter 3 and the pin ADC1+ output frequency with control of conversion device 3 respectively, the pin O/7 of programmable logic controller (PLC) 2 connects the pin DIN4 of frequency converter 3 to export reverse crawl signal, the pin O/6 of programmable logic controller (PLC) 2 connects the pin DIN3 of frequency converter 3 with output forward crawl signal, the pin DIN2 that the pin O/5 of programmable logic controller (PLC) 2 connects frequency converter 3 makes the oppositely signal of startup of frequency converter 3 with output, the signal that the pin DIN1 of the pin O/4 connection frequency converter 3 of programmable logic controller (PLC) 2 starts frequency converter 3 forwards with output, the pin O/2 of programmable logic controller (PLC) 2 connects the end of motor brake solenoid Q, the other end of motor brake solenoid Q connects 24 volts of low levels, the pin U of frequency converter 3, pin V and pin W are connected the three-phase terminal of motor respectively, and the pin B+ of frequency converter 3 connects the pin B-of frequency converter 3 by energy consumption resistance R.During work, 380 volts of alternating current inputs input to frequency converter 3 through isolating switch D1, contactor J1, programmable logic controller (PLC) 2 is according to the control procedure needs, the forward of control of conversion device 3 starts, oppositely starts action, and according to the operation curve that calculates, calculate the output frequency of frequency converter 3, output frequency by analog quantity output control of conversion device 3, control the rotating speed of motor 1 in real time, in a stroke cycle, realize to quicken, at the uniform velocity, deceleration, static steady commutation, quicken, at the uniform velocity, slow down, the smooth curve operation of steadily commutation.
It also comprises scrambler 6, the output terminals A of scrambler 6 connects the pin 1 of programmable logic controller (PLC) 2, and the output terminal B of scrambler 6 connects the pin O of programmable logic controller (PLC) 2, and scrambler 6 is gathered motor speed information, constitute closed-loop control system, regulate making system reach the control accuracy requirement with PID.The rotation speed change of motor 1 as shown in Figure 3.Can cause damage oil pumper physical construction or extremely serious consequences such as infringement oil well, sucker rod owing to cross the stroke fault; therefore reliable protective measure must be arranged; lower stroke switch K1, upper stroke switch K2 are installed in two ends in range; in case switch triggering just stops frequency converter; internal contracting brake provided, and provide alerting signal and failure diagnosis information.
Embodiment three: specify present embodiment below in conjunction with Fig. 1.Present embodiment and embodiment one or twos' difference is: the logic control element of programmable logic controller (PLC) 2 also comprises Based Intelligent Control diagnosis unit 2-7, to realize the whether detection of operate as normal of lower stroke switch K1, upper stroke switch K2, position switch 4, scrambler 6.So be provided with, system is long-time can be pressed the self check button after shutting down the sensor of system is detected, and allows operational system when not occurring reporting to the police.Constantly the sensor to key detects when system moves, the halt system in case sensor breaks down, and provide alerting signal.
Based Intelligent Control diagnosis unit 2-7 utilizes scrambler to calculate stroke, carries out 2 grades of protections of stroke, and calculates rotating speed according to the feedback signal of scrambler 6; compare with theoretical rotational speed; thereby judge disconnected bar and broken belt fault, protect, and provide alerting signal and failure diagnosis information.Regular meeting fluctuates during the load of oil well; this fluctuation of load may cause motor moment excess current; for fear of the overcurrent protection misoperation; in Based Intelligent Control diagnosis unit 2-7, added moment excess current inhibit feature; and, calculate the poor of counterweight and load by comparing the electric current of upstroke and down stroke.Can cause the waste of the energy under the inappropriate situation of counterweight, and cause bigger mechanical wear.If imbalance then give the alarm, the prompting staff notes, shuts down when serious, to prevent electromotor overload and mechanical wear.The sucker rod and the counterweight of oil pumper assigned address can be docked to by the crawl control function, and counterweight can be when aboveground operation, directly promoted.Based Intelligent Control diagnosis unit 2-7 can also carry out fault diagnosis and provide the malfunction elimination indication improper shutdown.
Claims (6)
1, the frequency-changing control system of long-stroke pumping unit without walking beam, it comprises motor (1), it is characterized in that it also comprises programmable logic controller (PLC) (2) and frequency converter (3), the output terminal of programmable logic controller (PLC) (2) is connected to the input end of frequency converter (3) to finish the control to frequency converter (3) output frequency and phase sequence, the feedback output end of frequency converter (3) is connected to frequency and the electric current of the analog quantity input end of programmable logic controller (PLC) (2) with feedback inverter, the power output end of frequency converter (3) is connected to sense of rotation and the rotating speed of the power end of motor (1) with control motor (1), program in the programmable logic controller (PLC) (2) is by the control of frequency converter (3) realization to motor 1 rotational speed and direction, program comprises that forward quickens control module (2-1), with by frequency converter (3) control motor (1) from initial position according to the acceleration operation of appointment to forward position at the uniform velocity; Forward is control module (2-2) at the uniform velocity, at the uniform velocity to travel at the uniform speed to the forward decelerate position according to the speed of appointment the position from forward by frequency converter (3) control motor (1); Forward deceleration control unit (2-3), with by frequency converter (3) control motor (1) from the forward decelerate position according to the acceleration of appointment run slowly to motor (1) speed moment serve as zero; Oppositely quicken control module (2-4), with by frequency converter (3) control motor (1) from zero velocity according to the acceleration operation of appointment to reverse position at the uniform velocity; Reverse control module (2-5) at the uniform velocity is at the uniform velocity to travel at the uniform speed to reverse decelerate position according to the speed of appointment the position from forward by frequency converter (3) control motor (1); Reverse deceleration control unit (2-6), running slowly to initial position from the acceleration of reverse decelerate position according to appointment by frequency converter (3) control motor (1), and to make motor speed moment be zero.
2, the frequency-changing control system of long-stroke pumping unit without walking beam according to claim 1, it is characterized in that it also comprises position switch (4), program also comprises stroke initial position fix unit (2-8), and position switch (4) is connected the input end of programmable logic controller (PLC) (2).
3, the frequency-changing control system of long-stroke pumping unit without walking beam according to claim 1 is characterized in that it also comprises man-machine interface (5), and man-machine interface (5) links to each other with the communication port of programmable logic controller (PLC) (2).
4, the frequency-changing control system of long-stroke pumping unit without walking beam according to claim 1 is characterized in that it also comprises scrambler (6), and the output terminal of scrambler (6) connects the input end of programmable logic controller (PLC) (2).
5, the frequency-changing control system of long-stroke pumping unit without walking beam according to claim 1 and 2, it is characterized in that it also comprises contactor (J1), isolating switch (D1), lower stroke switch (K1), upper stroke switch (K2), forward inching button (K3), reverse inching button (K4), stop button (K5), start button (K6), power-on self-test button (K7), motor brake solenoid (Q) and energy consumption resistance (R), the pin L1 of frequency converter (3), pin L2 and pin L3 are connected on the three-phase output end of contactor (J1), the three-phase input end of contactor (J1) is connected on the three-phase output end of isolating switch (D1), the pin DAC2-of frequency converter (3) and pin DAC2+ are connected the pin A3-of programmable logic controller (PLC) (2) and pin A3 respectively to realize current feedback, the pin DAC1-of frequency converter (3) and pin DAC1+ are connected the pin A2-of programmable logic controller (PLC) (2) and pin A2 respectively to realize frequency feedback, the pin DO1/NO of frequency converter (3) connects the pin 11 of programmable logic controller (PLC) (2) to realize the frequency converter failure feedback, the pin 10 of programmable logic controller (PLC) (2) is connected on the output terminal of position switch (4), the pin 9 of programmable logic controller (PLC) (2) is connected to the output terminal of lower stroke switch (K1), the input end of lower stroke switch (K1) connects 24 volts of high level, the pin 8 of programmable logic controller (PLC) (2) is connected on the output terminal of upper stroke switch (K2), the input end of upper stroke switch (K2) connects 24 volts of high level, the pin 7 of programmable logic controller (PLC) (2) connects the output terminal of forward inching button (K3), the input end of forward inching button (K3) connects 24 volts of high level, the pin 6 of programmable logic controller (PLC) (2) is connected to the output terminal of reverse inching button (K4), oppositely the input end of inching button (K4) connects 24 volts of high level, the pin 5 of programmable logic controller (PLC) (2) connects the output terminal of stop button (K5), the input end of stop button (K5) connects 24 volts of high level, the pin 4 of programmable logic controller (PLC) (2) is connected to the output terminal of start button (K6), the input end of start button (K6) connects 24 volts of high level, the pin 3 of programmable logic controller (PLC) (2) is connected to the output terminal of power-on self-test button (K7), the input end of power-on self-test button (K7) connects 24 volts of high level, the pin OA-of programmable logic controller (PLC) (2) and pin V+ are connected the pin ADC1-of frequency converter (3) and the pin ADC1+ output frequency with control of conversion device (3) respectively, the pin 0/7 of programmable logic controller (PLC) (2) connects the pin DIN4 of frequency converter (3) to export reverse crawl signal, the pin 0/6 of programmable logic controller (PLC) 2 connects the pin DIN3 of frequency converter 3 with output forward crawl signal, the pin DIN2 that the pin 0/5 of programmable logic controller (PLC) (2) connects frequency converter (3) makes the oppositely signal of startup of frequency converter (3) with output, the signal that the pin DIN1 of the pin 0/4 connection frequency converter (3) of programmable logic controller (PLC) (2) starts frequency converter (3) forward with output, the pin 0/2 of programmable logic controller (PLC) (2) connects an end of motor brake solenoid (Q), the other end of motor brake solenoid (Q) connects 24 volts of low levels, the pin U of frequency converter (3), pin V and pin W are connected the three-phase terminal of motor respectively, and the pin B+ of frequency converter (3) connects the pin B-of frequency converter (3) by energy consumption resistance R.
6,, it is characterized in that the program of programmable logic controller (PLC) (2) also comprises Based Intelligent Control diagnosis unit (2-7) according to the frequency-changing control system of claim 1,2,4 or 5 described long-stroke pumping unit without walking beam.
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CNA2006100100128A CN1845024A (en) | 2006-04-30 | 2006-04-30 | Frequency conversion control system of long-stroke pumping unit without walking beam |
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CNA2006100100128A CN1845024A (en) | 2006-04-30 | 2006-04-30 | Frequency conversion control system of long-stroke pumping unit without walking beam |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101871337A (en) * | 2010-06-22 | 2010-10-27 | 上海神源电气有限公司 | Method for controlling tower-type pumping unit |
CN102591225A (en) * | 2012-02-20 | 2012-07-18 | 杭州南源科技有限公司 | Intelligent variable frequency controller |
CN106223904A (en) * | 2016-09-14 | 2016-12-14 | 赵国祥 | Blue elephant Intelligent electronic control system |
CN109098696A (en) * | 2018-07-03 | 2018-12-28 | 深圳市蓝海华腾技术股份有限公司 | A kind of tower shelf type oil pumping machine position control method |
-
2006
- 2006-04-30 CN CNA2006100100128A patent/CN1845024A/en active Pending
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101871337A (en) * | 2010-06-22 | 2010-10-27 | 上海神源电气有限公司 | Method for controlling tower-type pumping unit |
CN101871337B (en) * | 2010-06-22 | 2013-10-02 | 上海神源电气有限公司 | Method for controlling tower-type pumping unit |
CN102591225A (en) * | 2012-02-20 | 2012-07-18 | 杭州南源科技有限公司 | Intelligent variable frequency controller |
CN106223904A (en) * | 2016-09-14 | 2016-12-14 | 赵国祥 | Blue elephant Intelligent electronic control system |
CN106223904B (en) * | 2016-09-14 | 2019-04-26 | 赵国祥 | Blue elephant Intelligent electronic control system |
CN109098696A (en) * | 2018-07-03 | 2018-12-28 | 深圳市蓝海华腾技术股份有限公司 | A kind of tower shelf type oil pumping machine position control method |
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