CN106452270B - Oil immersion line motor collision checking method - Google Patents

Abstract

The invention discloses a kind of collision checking method for oil immersion line motor, the motion process of the oil immersion line motor includes movement phase and waiting period, the method includes：Electric current, voltage or power information based on the oil immersion line motor obtain collision information.The detection method of the present invention does not depend on position sensor, and the current sensor real-time sampling linear motor stator electric electric current positioned at well head is used only.Master board calculates collision characteristic quantity after handling the stator current detected, can determine whether motor collides by the value of this feature amount.The detection method hardware cost is low, and detection speed is fast, and software phase lock loop is good, to realize that the intelligent control of linear motor provides important means.

Description

Oil immersion line motor collision checking method

Technical field

The invention belongs to oil exploration equipment fields, and in particular to a kind of oil immersion line motor collision checking method.

Background technology

During oil extraction in oil field, generally use beam pumping unit, this oil production method will by mechanically operated mode The rotary motion of belt pulley is converted to pumping for sucker rod, so simple in structure, reliability is high, but there are transmission rings Save the deficiencies of loss in efficiency is big, side-abrasion of rod string and noise are big.

Using the pumping unit of latent oil reciprocating linear electric motor, driving motor is cylindrical linear motor, the motor stator Coil is sealed in outer barrel, inner cylinder be by set of permanent magnets at mover, to stator input three-phase alternating voltage, you can driving mover It pumps.Because opposite kowtowing machine eliminates rotary motion to the conversion links of linear motion, oil-submersible linear Electric efficiency is improved.

But due to installing sensor without enough installation spaces in linear motor, reliability is caused to reduce.In view of latent The typically no position sensor of linear electric machine with oil, linear motor rotor displacement can only realize the open loop control based on synchronous motor characteristic System, therefore rotor position can not accurately control.Since underground is inevitably present linear motor sand card, oil pumping bump leakage/pumping Phenomena such as sky, control error, these factors will cause the rotor position of opened loop control that deviation occurs, and position deviation is by a timing Between accumulation after, it is more likely that cause electric mover and the limiting device of stator upper and lower ends to collide.Frequently occur in this way Collision, motor stator outer barrel Mechanical Structure Strength will be caused to reduce even damaged, well liquid will be led after entering stator from breakage It causes fixed subcoil insulating to reduce even short circuit, reduces electrical machinery life, improve operation expense.

Invention content

In view of the above-mentioned problems, the purpose of the present invention is to provide a kind of collision checking methods for direct current generator, once The up/down limiting device of mover and stator collides, and this method can detect collision phenomenon at once, subsequently to take school Positive measure provides important evidence.

Specifically, the present invention provides a kind of collision checking method for oil immersion line motor, the oil-submersible linear Motor includes stator and mover, position limit device and lower caging device is provided on the stator, the mover is in the upper limit It is moved back and forth before position device and lower caging device, motion process includes movement phase and waiting period, which is characterized in that the side Method includes：Electric current, voltage or power information based on the oil immersion line motor obtain collision information.

Further, the method includes following step：

Step (1) samples the stator current of the oil immersion line motor；

Step (2) is filtered institute's sample rate current；

Step (3), the stator input voltages frequency f for obtaining the oil immersion line motor；

Step (4) calculates the oil immersion line motor according to the stator input voltages frequency f of the oil immersion line motor The real-time speed v=2 τ f of mover, v is the mover movement velocity of linear motor in formula, and τ is the pole span of linear motor；

Step (5), the real-time speed based on the mover calculated calculate the displacement of the mover, s=∑s vT_s, public In formula, s is the real-time displacement of the mover, T_sIt is calculating cycle；

Real-time displacement value s of the step (6) based on the mover being calculated and setting shift value S_SETIt is compared；

Step (7) is if s >=S_SET, judge that this motion process smoothly terminates, the stator not with position limit device and under Any one in limiting device collides；

Step (8) if, real-time displacement value s<S_SET, assert and be currently in the movement phase, calculate present current value to the time Change rate, [i (k)-i (k-1)]/T_s, in formula, i (k) is the stator current value that current sample period obtains, on i (k-1) is The stator current value that one sampling period obtains, T_sIt is the program interrupt period；

Current point is determined as staying for current waveform by step (9) if the absolute value of slope is less than or equal to predetermined threshold Point, to being judged as the point in stationary point, at the time of recording current, and by the current time recorded and at the time of a upper adjacent stationary point Value makes the difference to obtain the time interval in two stationary points；

Step (10) if, the absolute value of slope be more than predetermined threshold, it is current waveform stationary point to judge current point not；

Whether step (11), the time interval in two stationary points of judgement are in 0.4~0.6 times of input voltage periodic regime, such as Fruit time interval in 0.4~0.6 times of input voltage periodic regime, then judge the stator not with position limit device and lower limit Any one in device collides；If time interval is less than 0.4 times of input voltage period, judge that the stator touches It hits；

Step (12), in waiting period, stationary point is recorded clear 0, for next round detection prepare.

Further, the predetermined threshold is 0.05.

The method of the present invention is realized by a control circuit comprising 12 pulsating wave auto-transformer, the first three-phase bridge Uncontrollable rectifier module REC₁, the second three-phase bridge uncontrollable rectifier module REC₂, the first paralleing reactor L₁, the second paralleing reactor L₂, the first, second, third IGBT half-bridge modules, the first, second, and third output inductor L₃、L₄、L₅, first, second, Three filter capacitor C₁、C₂、C₃,

The 12 pulsating wave auto-transformer exports two groups of three-phase alternating voltage A₁B₁C₁And A₂B₂C₂, this two groups of three-phase voltages The phase difference of corresponding phase is 30 degree, three-phase voltage A₁B₁C₁Input the first three-phase bridge uncontrollable rectifier module REC₁, three-phase voltage A₂B₂C₂Input the second three-phase bridge uncontrollable rectifier module REC₂, the first three-phase bridge uncontrollable rectifier module REC₁, the second three-phase bridge Formula uncontrollable rectifier module REC₂The anode of output is connected respectively to the first paralleing reactor L₁Two-end-point, the first three-phase bridge are not controlled Rectification module REC₁, the second three-phase bridge uncontrollable rectifier module REC₂The cathode of output is connected respectively to the second paralleing reactor L₂ Two-end-point, the first paralleing reactor L₁Midpoint be connected to dc-link capacitance C_dcAnode, the second paralleing reactor L₂In Point is connected to dc-link capacitance C_dcCathode to dc-link capacitance C_dcPositive and negative anodes be separately connected 3 IGBT half-bridge modules Both ends, the midpoint of three IGBT half-bridge modules passes through the first, second, third output inductor L respectively₃、L₄、L₅。

Present applicant is found through experiments that, when mover and the stator position-limit mechanism of motor collide, stator electricity Pressure/electric current can occur significantly to distort, therefore some collision characteristic quantities can be extracted by the voltage/current of distortion to determine whether It collides.Therefore, the present invention judges to collide using motor electronic electric current, the specific implementation process is as follows：The phase is moved in mover Between current Hall sensor real-time sampling motor stator electric current always, the sample rate current of current Hall output completes hardware filtering Be sent into core controller (generally DSP, microcontroller or ARM chips) after conditioning, core controller is to stator current into line number Wordization samples.It is presently at upper and lower run the period still by comparing whether current real-time displacement reaches setting shift value judgement Waiting period, if current real-time displacement is currently at waiting period not less than setting shift value, program is sentenced without collision Disconnected, if current real-time displacement is less than setting shift value, current mover is in up/down run the period, and program calculates touch in real time Hit characteristic quantity, collision characteristic quantity can be electric current THD (total harmonic distortion factor), the zero sequence of threephase stator electric current and negative sequence component, Time interval, current changing rate etc. between the adjacent stationary point of electric current short time average, current waveform, these collision characteristic quantities are colliding It is front and back to occur significantly to change, therefore can be determined whether by the value of collision characteristic quantity and be collided.

It is an advantage of the invention that：1, hardware cost is low；2, detection speed is fast；3. software phase lock loop is good.

Description of the drawings

Fig. 1 is performed for the circuit topology of the switch board of the method for the present invention；

Stator voltage practical measurement of current waveform when Fig. 2 is the operation of linear motor normal circulation；

Fig. 3 is stator voltage electric current in the front and back measured waveform that collides；

Fig. 4 is the flow chart of the collision checking method of the present invention.

Specific implementation mode

Below in conjunction with attached drawing and embodiment, the present invention is described in detail, but not therefore by the protection model of the present invention It encloses and is limited among the range of embodiment description.

Fig. 1 is performed for the switch board circuit topology of the method for the present invention.The switch board circuit is used for the reciprocating pumping of latent oil Oil machine.As shown in Figure 1, three-phase alternating current input voltage inputs a 12 pulsating wave auto-transformer, auto-transformer output two Group three-phase alternating voltage A₁B₁C₁And A₂B₂C₂, the phase difference that this two groups of three-phase voltages correspond to phase is 30 degree, i.e. A₁、B₁、C₁Phase Advanced or lag A₂、B₂、C₂30 degree of phase.Three-phase voltage A₁B₁C₁Input three-phase bridge uncontrollable rectifier module REC₁, three-phase electricity Press A₂B₂C₂Input three-phase bridge uncontrollable rectifier module REC₂, rectification module REC₁And REC₂The anode of output is connected respectively to balance Reactor L₁Two-end-point, rectification module REC₁And REC₂The cathode of output is connected respectively to paralleing reactor L₂Two-end-point.Balance electricity Anti- device L₁Midpoint be connected to dc-link capacitance C_dcAnode, paralleing reactor L₂Midpoint be connected to dc-link capacitance C_dc Cathode.Q₁-Q₂,Q₃-Q₄,Q₅-Q₆For 3 IGBT half-bridge modules, Q₁, Q₃, Q₅For the upper tube of this 3 half-bridge modules, their collection Electrode is all connected to dc-link capacitance C_dcAnode, Q₂, Q₄, Q₆For the down tube of this 3 half-bridge modules, their emitter all connects To dc-link capacitance C_dcCathode.Q₁, Q₃, Q₅Emitter be connected to output inductor L₃, L₄, L₅Input side.3 filtering Capacitance C₁, C₂, C₃It is connected across filter inductance L₃, L₄, L₅Outlet side.The stator coil of linear motor passes through latent oil armored cable point It is not connected to filter inductance L₃, L₄, L₅Outlet side.In switch board, two current Halls sample two-way motor electronic electricity respectively Stream, for carrying out collision detection；The master board drive that output drive signal inputs master board to driving plate, driving plate simultaneously Dynamic signal exports 6 switching tubes of the 6 road drive signals to 3 half-bridge IGBT modules, driving switch pipe copped wave fortune after being handled Row.

Stator voltage practical measurement of current waveform when Fig. 2 is the operation of linear motor normal circulation.Waveform top box is general view Figure, lower part box are the enlarged drawing of the small box in right side in synoptic chart.It is stator current wave to be maintained in waveform in two lines frame Shape, wave crest are stator line voltage waveforms more than wire frame.In synoptic chart, it is mover that voltage current waveform, which is the sinusoidal period, Movement slot, at this moment according to the different phase sequences of stator voltage, mover is run upward or downward.Voltage current waveform is straight line Period is mover waiting period, and this period, switch board no longer output AC voltage driving mover moved, after the completion of the stand-by period, Stator voltage phase sequence reverse phase, mover commutation operation.In conclusion the moving law of linear motor be run down-wait for-upwards Operation-waiting, and with the continuous circular flow of this rule.When can be seen that motor operation from the enlarged drawing of waveform lower part, electric current For good sinusoidal waveform, thus electric current THD is small, and the time interval on current waveform between adjacent stationary point is 1/2 period, electric current pair Time rate of change changes in sinusoidal rule.

Fig. 3 is stator current in the front and back measured waveform that collides.What peak value was low in figure is stator current waveforms, peak value High is stator line voltage waveform.Mover collides with stator position-limit mechanism at the time of waveform center longitudinal axis corresponds to, can be with Before seeing that collision occurs, current waveform is in more good sinusoidal waveform, and after collision occurs, apparent distortion, wave occur for current waveform The THD of shape increases, and the absolute value of Current versus time change rate significantly increases, and the time interval on current waveform between adjacent stationary point is bright It is aobvious to reduce.

Fig. 4 is the program flow diagram of collision detection algorithm.This example according between adjacent stationary point in stator current waveforms when Between interval judge whether current waveform is distorted, and then judge whether to collide.Program circuit is as follows：Into after program, Master control borad samples stator current and does software filtering removal interference first, and it is real to calculate mover further according to present input voltage frequency f Shi Sudu, i.e. v=2 τ f, v is the mover movement velocity of linear motor in formula, and τ is the pole span of linear motor, this be one often Amount, f is the frequency of stator voltage, is controlled by control panel, is a known quantity.And further calculate mover displacement, i.e. s=∑s vT_s, in formula, s is the real-time displacement of mover, and v is the mover movement velocity of linear motor, T_sIt it is the program interrupt period, to ensure Computational accuracy, generally musec order.By the real-time displacement value s being calculated and setting shift value S_SET(setting shift value is by electricity The maximum stroke that machine structure allows is determined with beam-pumping unit jig frequency, discharge capacity) it compares, if s>=S_SET, illustrate this motion process Smoothly terminate, do not send collision, in waiting time by stationary point moment value clear 0, prepares for next round detection；If real-time displacement Value s<S_SET, illustrate currently to be in motion process, at this moment calculating present current value is to time rate of change, i.e. [i (k)-i (k- 1)]/T_s, in formula, i (k) is the stator current value that current sample period obtains, and i (k-1) upper sampling period obtains Stator current value, T_sIt is the program interrupt period.If slope illustrates that current point is close to 0, such as between -0.05~0.05 The stationary point of current waveform, if it is current waveform stationary point that slope, which not in this range, illustrates current point not,.To being judged as stationary point Point, at the time of recording current, and and record a upper adjacent stationary point at the time of value make the difference to obtain the time interval in two stationary points. When not colliding, which is 0.5 times of input voltage period, and after colliding, which can greatly reduce.Root Detect the time interval between adjacent stationary point according to this principle, if the time interval 0.4~0.6 times of input voltage period, Illustrate that current waveform does not send distortion, motor does not collide；If the time interval illustrates electricity 0~0.4 times of input voltage period Stream waveform is distorted, and motor collides.To further increase the reliability of judgement, can repeatedly it be judged, if detection It collides to continuous several times (such as 3 times), i.e. judgement collides.

Although the principle of the present invention is described in detail above in conjunction with the preferred embodiment of the present invention, this field skill Art personnel are it should be understood that above-described embodiment is only the explanation to the exemplary implementation of the present invention, not to present invention packet Restriction containing range.All within the spirits and principles of the present invention, above example is done according to the technical essence of the invention Any simple modification, equivalent change and modification, still fall within protection scope of the present invention.

Claims (2)

1. a kind of collision checking method for oil immersion line motor, the oil immersion line motor includes stator and mover, described It is provided with position limit device and lower caging device on stator, the mover is gone to the position limit device and lower caging device Multiple movement, motion process includes movement phase and waiting period, which is characterized in that the method includes：Based on the oil-submersible linear Electric current, voltage or the power information of motor obtain collision information, and the method includes following step：

Step (1) samples the stator current of the oil immersion line motor；

Step (2) is filtered institute's sample rate current；

Step (3), the stator input voltages frequency f for obtaining the oil immersion line motor；

Step (4) calculates the mover of the oil immersion line motor according to the stator input voltages frequency f of the oil immersion line motor Real-time speed v=2 τ f, v is the mover movement velocity of linear motor in formula, and τ is the pole span of linear motor；

Step (5), the real-time speed based on the mover calculated calculate the displacement of the mover, s=∑s vT_s, in formula, s For the real-time displacement of the mover, T_sIt is calculating cycle；

Real-time displacement value s of the step (6) based on the mover being calculated and setting shift value S_SETIt is compared；

Step (7) is if s >=S_SET, judge that this motion process smoothly terminates, the stator not with position limit device and lower limit Any one in device collides；

Step (8) if, real-time displacement value s<S_SET, assert and be currently in the movement phase, calculate present current value to time change Rate, [i (k)-i (k-1)]/T_s, in formula, i (k) is the stator current value that current sample period obtains, and i (k-1) is upper one The stator current value that sampling period obtains, T_sIt is the program interrupt period；

Current point is determined as the stationary point of current waveform by step (9) if the absolute value of slope is less than or equal to predetermined threshold, right It is judged as the point in stationary point, at the time of recording current, and the current time recorded and value at the time of a upper adjacent stationary point is done Difference obtains the time interval in two stationary points；

Step (10) if, the absolute value of slope be more than predetermined threshold, it is current waveform stationary point to judge current point not；

Step (11), judge two stationary points time interval whether in 0.4~0.6 times of input voltage periodic regime, if when Between be spaced in 0.4~0.6 times of input voltage periodic regime, then judge the stator not with position limit device and lower caging device In any one collide；If time interval is less than 0.4 times of input voltage period, judge that the stator collides；

Step (12), in waiting period, stationary point is recorded clear 0, for next round detection prepare.

2. the collision checking method according to claim 1 for oil immersion line motor, which is characterized in that the predetermined threshold Value is 0.05.