CN203926173U - Hoist fine motion control system - Google Patents
Hoist fine motion control system Download PDFInfo
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- CN203926173U CN203926173U CN201320588762.9U CN201320588762U CN203926173U CN 203926173 U CN203926173 U CN 203926173U CN 201320588762 U CN201320588762 U CN 201320588762U CN 203926173 U CN203926173 U CN 203926173U
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- oil hydraulic
- hydraulic motor
- pressure
- current
- value
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Abstract
The utility model discloses a kind of hoist fine motion control system, comprising: pressure transducer, be arranged on the pressure measurement interface of oil hydraulic motor with very first time gap periods to pressure comparator, send the oil hydraulic motor force value of measuring in real time; Pressure comparator, calculates the instantaneous pressure value of oil hydraulic motor before stopping last time and the difference between the current oil hydraulic motor force value receiving; PID controller, according to the difference receiving, calculating electric current increases value of slope; Current control unit, utilizes electric current to increase value of slope and predefined control current value produces the control electric current progressively increasing, and the control electric current of generation is offered to oil hydraulic pump.The utility model carries out fine motion control from compensating the angle of whole hydraulic control circuit leakage, avoids oil hydraulic motor to occur the problems such as impact, shake or downslide.
Description
Technical field
The utility model relates to crane control field, particularly a kind of hoist fine motion control system.
Background technique
At present increasing hoist adopts automatically controlled mode on action control, even if control the action executing of the hydraulic mechanisms such as oil hydraulic pump, oil hydraulic motor with electric control handle, electromagnetic proportional valve, controller etc., and the corresponding upper and lower of controlling electric current of the aperture of handle.When simplifying system, also band is served the problem in control, and it is exactly one of them that fine motion is controlled.Fine motion is herein controlled, and refers to that Joystick is at crack mouthful, while just having left dead zone range, and the control to hydraulic system.In addition, because oil hydraulic motor in hoist generally drives elevator, so emphasis be take elevator as example.
Fine motion controls that the problem the most often occurring is winch impact, elevator shake, elevator reversion, dead band is excessive and long (2-3s) consuming time etc., the main cause that causes above phenomenon is that control electric current and the brake switch of oil hydraulic pump do not have Proper Match in the volume of oil hydraulic circuit, be the leakage DQ of oil hydraulic circuit, it is subject to the influence of rotation speed of working pressure, hydraulic system friction gap, hydraulic oil viscosity and pump.
According to the moment formula of oil hydraulic motor: T=P * V, wherein T is oil hydraulic motor output torque, and P is its pressure, and V is its discharge capacity.When load one regularly, outside required torque remains unchanged, and V is constant during braking, so during crack mouthful of handle, affect the P that only has of fine motion control effect.Therefore the relation of handling P and DQ well is the key that fine motion is controlled.
For fine motion, control, a kind of technological scheme that is applied at present hoist is by increasing pressure compensator, carries out the leakage compensation of oil hydraulic motor.This scheme hydraulic system, except the elevator system such as oil hydraulic pump, oil hydraulic motor, break, need to be arranged in a pressure transducer between break and oil hydraulic motor, and pressure compensator and oil hydraulic motor are connected.
Concrete method is: first record the instantaneous pressure value of last oil hydraulic motor before stopping, then calculating the needed theoretical pressure value of the actual driving of motor, both subtract each other and obtain pressure set points.Therefore as long as when upper once motor action, the delivery pressure of pressure compensator is adjusted to pressure set points, and offers oil hydraulic motor, make the above-mentioned pressure set points of generation in its volume, just can realize the smooth running of motor, and electric current upper and lower corresponding to handle position fixed.
Prior art is carried out the leakage compensation of oil hydraulic motor method by increasing pressure compensator still has shortcomings:
1, the starting point of prior art scheme is the pressure losing in the process of compensation because of break brake fluid pressure motor, and while making to start, the pressure of oil hydraulic motor starts up to increase from compensatory pressure setting value next time.In whole oil hydraulic circuit, all there is a small amount of leakage in oil hydraulic pump, hydrovalve, oil hydraulic motor and oil circuit etc., and leak and affected by working pressure, rotating speed etc., and therefore during or the slow-speed of revolution large in working pressure, whole control loop all exists relatively large leakage.Therefore list compensates from oil hydraulic motor, controls electric current or at lower limit, can not when working pressure is large, realize accurate control, thereby there will be the consuming time longer of fine motion control during the crack mouth of handle.
2, motor theoretical pressure value is determined by calculating.There is various mechanical losss and power loss in hydraulic system itself, and when different operating pressure, rotating speed, temperature, even the gradient on hoist work ground has impact, even if therefore formula is considered these influence factors, still be difficult to reflect completely actual conditions, can cause the theoretical pressure value giving to be inaccurate, and then produce deviation.And the control structure of compensatory pressure setting value do not form closed loop, also just cannot revise, there is the possibility that further expands compensatory pressure deviation.
3, this scheme is not considered the impact of engine speed on hydraulic control circuit.Because engine speed is directly proportional to oil hydraulic pump rotating speed, when hydraulic pump discharge is identical, larger rotating speed can make oil hydraulic pump export more flow, even if now oil hydraulic pump moment is opened less discharge capacity, also may cause the impact of oil hydraulic motor.
4, the realization of this scheme need to be added pressure compensator.Therefore need on hydraulic package, redesign, and need to give its required installing space, this has just improved cost and installation requirement accordingly.Meanwhile, due to many one heavy controlling unit, also with regard to many fault points.And when compensation device is worked, it can carry out delivery pressure always, and self also there is leakage and loss, so also can cause energy waste.
Model utility content
The technical problems to be solved in the utility model is to provide a kind of hoist fine motion control system.The utility model carries out fine motion control from compensating the angle of whole hydraulic control circuit leakage, avoids oil hydraulic motor to occur the problems such as impact, shake or downslide.
According to an aspect of the present utility model, a kind of hoist fine motion control system is provided, comprising: oil hydraulic motor, pressure transducer, detection unit, pressure comparator, PID controller, current control unit, oil hydraulic pump, wherein:
Described pressure transducer is arranged on the pressure measurement interface of described oil hydraulic motor, and described pressure transducer comprises memory module; Described pressure comparator is connected with described detection unit with described pressure transducer respectively; Described pressure comparator, described PID controller, described current control unit, described oil hydraulic pump are connected successively with described oil hydraulic motor;
Described pressure transducer with very first time gap periods to pressure comparator, send the oil hydraulic motor force value of measuring in real time, the instantaneous pressure value of wherein said memory module memory oil hydraulic motor before stopping last time; Described detection unit detects handle and whether surpasses dead zone range; Described pressure comparator is when described detection unit detects handle over dead zone range, and the difference between the instantaneous pressure value by oil hydraulic motor before stopping last time and the current oil hydraulic motor force value receiving sends to described PID controller; Described PID controller receives described difference, and sends and control floor level of electric current and electric current increase value of slope to described current control unit; Described current control unit offers described oil hydraulic pump by control electric current; Described oil hydraulic pump is adjusted the input flow rate of oil hydraulic motor.
Preferably, described system also comprises display device, and wherein, described display device is connected with described pressure comparator with described current control unit respectively.
The utility model is by arranging a pressure transducer at oil hydraulic motor place, the pressure of oil hydraulic motor of take is controlled the current value of oil hydraulic pump as benchmark, leakage to whole hydraulic control circuit compensates, nature will mask the leakage contribution of other hydraulic partss, makes the speed of response of whole system faster; The utility model is used closed loop control to complete fine motion control simultaneously, steadily reliable, avoids producing and impacts and oscillatory occurences.
Accompanying drawing explanation
In order to be illustrated more clearly in the utility model embodiment or technological scheme of the prior art, to the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described below, apparently, accompanying drawing in the following describes is only embodiments more of the present utility model, for those of ordinary skills, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.
Fig. 1 is an embodiment's of the utility model hoist fine motion control system schematic diagram.
Fig. 2 is another embodiment's of the utility model hoist fine motion control system schematic diagram.
Embodiment
Below in conjunction with the accompanying drawing in the utility model embodiment, the technological scheme in the utility model embodiment is clearly and completely described, obviously, described embodiment is only the utility model part embodiment, rather than whole embodiments.To the description only actually of at least one exemplary embodiment, be illustrative below, never as any restriction to the utility model and application or use.Embodiment based in the utility model, those of ordinary skills are not making the every other embodiment who obtains under creative work prerequisite, all belong to the scope of the utility model protection.
Unless illustrate in addition, otherwise the parts of setting forth in these embodiments and positioned opposite, numeral expression formula and the numerical value of step not limited scope of the present utility model.
, it should be understood that for convenience of description, the size of the various piece shown in accompanying drawing is not to draw according to actual proportionate relationship meanwhile.
For the known technology of person of ordinary skill in the relevant, method and apparatus, may not discuss in detail, but in suitable situation, described technology, method and apparatus should be regarded as authorizing a part for specification.
In all examples with discussing shown here, it is exemplary that any occurrence should be construed as merely, rather than as restriction.Therefore, other example of exemplary embodiment can have different values.
It should be noted that: in similar label and letter accompanying drawing below, represent similar terms, therefore, once be defined in an a certain Xiang Yi accompanying drawing, in accompanying drawing subsequently, do not need it to be further discussed.
Fig. 1 is the schematic diagram of the utility model hoist fine motion control system.Hoist fine motion control system shown in Fig. 1 comprises pressure transducer 102, detection unit 103, pressure comparator 104, PID (the Proportion Integration Differentiation on the pressure measurement interface that is arranged on oil hydraulic motor 101, proportional-integral-differential) controller 105, current control unit 106, oil hydraulic pump 107, wherein:
Pressure transducer 102, for when oil hydraulic motor 101 starts, with very first time gap periods to pressure comparator 104, send the oil hydraulic motor force value of measuring in real time.
Whether detection unit 103, surpass dead zone range for detection of handle.
Pressure comparator 104, while surpassing dead zone range for handle detected when detection unit 103, calculates the instantaneous pressure value P of oil hydraulic motor 101 before stopping last time
mand the difference between the current oil hydraulic motor pressure value P receiving, and difference is sent to PID controller 105.
PID controller 105, for judging described instantaneous pressure value P according to the difference receiving
mwhether be greater than the current oil hydraulic motor pressure value P receiving; As described instantaneous pressure value P
mwhile being less than or equal to the current oil hydraulic motor pressure value P receiving, indicator current control unit 106 is by predefined control current value I
0as controlling floor level of electric current I
minoffer oil hydraulic pump 107; As described instantaneous pressure value P
mwhile being greater than the current oil hydraulic motor pressure value P receiving, utilize described difference to determine that electric current increases value of slope I
k, electric current is increased to value of slope I
ksend to current control unit 106, wherein electric current increases value of slope I
kreducing and reduce with described difference.
Current control unit 106, for according to the indication of PID controller, by predefined control current value I
0as controlling floor level of electric current I
minoffer oil hydraulic pump 107; Also for utilizing the electric current receiving from PID controller to increase value of slope I
kwith predefined control current value I
0produce the control electric current progressively increasing, and the control electric current of generation is offered to oil hydraulic pump 107.
Oil hydraulic pump 107, for adjusting the input flow rate of oil hydraulic motor 101 according to the control electric current receiving.
The hoist fine motion control system providing based on the utility model above-described embodiment, pressure by oil hydraulic motor is the current value that benchmark is controlled oil hydraulic pump, leakage to whole hydraulic control circuit compensates, nature will mask the leakage contribution of other hydraulic partss, makes the speed of response of whole system faster; A pressure transducer only need be set at oil hydraulic motor place and just can realize good fine motion control, this is all very favorable at aspects such as cost, malfunction elimination, installation, the system energy; With real-time pressure and last time memory pressure compare, there is not the theoretical deviation of introducing of calculating; The utility model is used closed loop control to complete fine motion control simultaneously, steadily reliable, avoids producing and impacts and oscillatory occurences.
Preferably, pressure transducer 102 can comprise a memory module, for remembering the instantaneous pressure value P of oil hydraulic motor 101 before stopping last time
m.
Preferably, in described system, PID controller 105 can also be for utilizing described difference to determine that electric current increases value of slope I in execution
k, electric current is increased to value of slope I
kafter sending to the operation of current control unit 106, according to the difference receiving, judging described instantaneous pressure value P
mwhile equaling the current oil hydraulic motor pressure value P receiving, it is constant that indicator current control unit 106 maintains current control current value, and using current control current value as controlling lower current limit I
minoffer oil hydraulic pump 107.
Preferably, in described system, PID controller 105 can also be for when handle be got back to dead zone range, and indicator current control unit 106 is by predefined control current value I
0as controlling lower current limit I
minoffer oil hydraulic pump 107.
Preferably, in described system, current control unit 106 can utilize formula I
1=I
k+ I
0obtain current control electric current I
1; By current control electric current I
1offer oil hydraulic pump 107; After second time lag, by current control electric current I
1as I
0, carry out and utilize formula I
1=I
k+ I
0obtain the operation of current control electric current I 1.
Preferably, in described system, second time lag was less than very first time interval, and very first time interval is the pressure measurement time lag, and second time lag was to utilize electric current to increase value of slope I
kcalculate the time lag of controlling electric current.
Preferably, in described system, very first time interval and second time lag all can be between 10-50ms.In a preferred embodiment, the very first time is spaced apart 20ms, and second time lag was 10ms.
Preferably, in described system, PID controller 105 can utilize described difference to determine that electric current increases value of slope I
k; Then utilize formula I
k'=I
k* N
min/ N calculates electric current increases value of slope I
kcorrection value I
k', the rotating speed that wherein N is current oil hydraulic motor, N
minidling for oil hydraulic motor; Then by described correction value I
k' send to current control unit 106.
Wherein, I
kcorrection value I
k' formula I
k'=I
k* N
minthe process of pushing over of/N is:
According to the flow rate calculation formula q=v * n of oil hydraulic pump, the output flow that wherein q is oil hydraulic pump, v is hydraulic pressure pump delivery, the rotating speed that n is oil hydraulic pump;
Consider that engine speed and oil hydraulic pump rotation speed relation meet formula n=N * k, the rotating speed that wherein N is motor, k is the rotating ratio of engine speed and oil hydraulic pump rotating speed, can obtain q=v * N * k, when hydraulic pressure pump delivery is constant, if engine speed changes, the flow of oil hydraulic pump also can change so;
Consider that pressure and oil hydraulic pump flow in hydraulic control circuit have direct relation, in order to eliminate the impact of engine speed, therefore with engine idle N
minas benchmark, hydraulic pressure pump delivery is carried out to following change: q=(v * N
min/ N) * N * k, at original electric current value of slope I
kon basis, according to formula I
k'=I
k* N
min/ N revises.
The hoist fine motion control system providing based on the utility model above-described embodiment, removed the impact of engine speed on electric current slope control, the rotating speed different according to motor, produces different electric current value of slope, impels the pressure of hydraulic control circuit rationally to improve; And the moment that can not open at hydraulic pump discharge causes the impact phenomenon of oil hydraulic motor because the too much build-up of pressure of flow is too high.
Preferably, described system realizes in the following way the fine motion of hoist is controlled:
When oil hydraulic motor starts, pressure transducer with very first time gap periods to pressure comparator, send the oil hydraulic motor force value of measuring in real time, wherein pressure transducer is arranged on the pressure measurement interface of oil hydraulic motor.
When handle surpasses dead zone range, pressure comparator calculates the instantaneous pressure value P of oil hydraulic motor before stopping last time
mand the difference between the current oil hydraulic motor pressure value P receiving, and difference is sent to PID controller.
PID controller judges described instantaneous pressure value P according to the difference receiving
mwhether be greater than the current oil hydraulic motor pressure value P receiving.
If described instantaneous pressure value P
mbe less than or equal to the current oil hydraulic motor pressure value P receiving, PID controller indicator current control unit is by predefined control current value I
0as controlling floor level of electric current I
minoffer oil hydraulic pump.
If described instantaneous pressure value P
mbe greater than the current oil hydraulic motor pressure value P receiving, PID controller utilizes described difference to determine that electric current increases value of slope I
k, wherein electric current increases value of slope I
kreducing and reduce with described difference; Utilize formula I
k'=I
k* N
min/ N calculates electric current increases value of slope I
kcorrection value I
k', the rotating speed that wherein N is current oil hydraulic motor, N
minidling for oil hydraulic motor; Electric current is increased to value of slope I
k' send to current control unit.
Current control unit utilizes formula I
1=I
k'+I
0obtain current control electric current I
1; By current control electric current I
1offer oil hydraulic pump; After second time lag, by current control electric current I
1as I
0, carry out and utilize formula I
1=I
k+ I
0obtain current control electric current I
1operation; Then after each second time lag, all by current control electric current I
1as I
0, carry out and utilize formula I
1=I
k+ I
0obtain current control electric current I
1step, that is, and current control electric current I after each second time lag
1all increase I
k, form circulation.
When PID controller judges described instantaneous pressure value P according to the difference receiving
mwhile equaling the current oil hydraulic motor pressure value P receiving, it is constant that indicator current control unit maintains current control current value, and using current control current value as controlling lower current limit I
minoffer oil hydraulic pump.
When handle is got back to dead zone range, PID controller indicator current control unit is by predefined control current value I
0as controlling lower current limit I
minoffer oil hydraulic pump.
Finally, oil hydraulic pump is adjusted the input flow rate of oil hydraulic motor according to the control electric current receiving.
Fig. 2 is another embodiment's of the utility model hoist fine motion control system schematic diagram.Compare with embodiment illustrated in fig. 1, in embodiment illustrated in fig. 2, hoist fine motion control system can also comprise display unit 201, wherein:
Display unit 201, for showing the instantaneous pressure value P of oil hydraulic motor before stopping last time
mwith the current oil hydraulic motor pressure value P receiving, and current control current value.
Preferably, display unit 201 can also be for approaching or be greater than the instantaneous pressure value P before stopping last time in the current oil hydraulic motor pressure value P receiving
mtime, point out or report to the police, thereby making hoist manipulator know current state.
By implementing the utility model, can obtain following beneficial effect:
1, the utility model compensates the leakage of whole hydraulic control circuit.Because the final stage of oil hydraulic motor in control loop, and whole flows is all to supply with by oil hydraulic pump, therefore the pressure of oil hydraulic motor of take is controlled the current value of oil hydraulic pump as benchmark, lower current limit is followed working pressure and is changed, that the leakage of whole control loop is compensated, nature will mask the leakage contribution of other hydraulic partss, makes the speed of response of whole system faster.
2, the utility model with real-time pressure and last time memory pressure compare, there is not the theoretical deviation of introducing of calculating.The measurement environment of memory pressure and actual pressure is almost identical, therefore can mask the impact of working pressure, temperature, rotating speed.
3, system control structure of the present utility model forms closed-loop feedback with oil hydraulic motor real-time pressure, uses PID to control the adjustment of carrying out the electric current gradient: the electric current gradient is directly proportional to two pressure differences; When two force value are identical, maintain current control electric current, thereby avoided that electric current excessively impacts, the too small appearance reversion of electric current, electric current shakiness cause the phenomenons such as shake, realizes the stable control of system.
4, the utility model has been removed the impact of engine speed on electric current slope control, and the rotating speed different according to motor produces different electric current value of slope, impels the pressure of hydraulic control circuit rationally to improve; And the moment that can not open at hydraulic pump discharge causes the impact phenomenon of oil hydraulic motor because the too much build-up of pressure of flow is too high.
5, enforcement of the present utility model only need arrange at oil hydraulic motor place a pressure transducer.For automatically controlled hoist, pressure transducer is generally to install for the oil hydraulic motor as promoting, therefore without extra device, just can realize good fine motion and control, this is all very favorable at aspects such as cost, malfunction elimination, installation, the system energy.
Description of the present utility model provides for example with for the purpose of describing, and is not exhaustively or by the utility model to be limited to disclosed form.Many modifications and variations are obvious for the ordinary skill in the art.Selecting and describing embodiment is for better explanation principle of the present utility model and practical application, thereby and makes those of ordinary skill in the art can understand the various embodiments with various modifications that the utility model design is suitable for special-purpose.
Claims (2)
1. a hoist fine motion control system, is characterized in that, comprising:
Oil hydraulic motor, pressure transducer, detection unit, pressure comparator, PID controller, current control unit, oil hydraulic pump, wherein:
Described pressure transducer is arranged on the pressure measurement interface of described oil hydraulic motor, described pressure transducer comprises memory module, described pressure comparator is connected with described detection unit with described pressure transducer respectively, described pressure comparator, described PID controller, described current control unit, described oil hydraulic pump are connected successively with described oil hydraulic motor, the pressure of oil hydraulic motor of take is controlled the current value of oil hydraulic pump as benchmark, use closed loop control to complete fine motion and control, wherein:
Described pressure transducer with very first time gap periods to pressure comparator, send the oil hydraulic motor force value of measuring in real time, the instantaneous pressure value of wherein said memory module memory oil hydraulic motor before stopping last time; Described detection unit detects handle and whether surpasses dead zone range; Described pressure comparator is when described detection unit detects handle over dead zone range, and the difference between the instantaneous pressure value by oil hydraulic motor before stopping last time and the current oil hydraulic motor force value receiving sends to described PID controller; Described PID controller receives described difference, and sends and control floor level of electric current and electric current increase value of slope to described current control unit; Described current control unit offers described oil hydraulic pump by control electric current; Described oil hydraulic pump is adjusted the input flow rate of oil hydraulic motor according to the control electric current receiving.
2. system according to claim 1, also comprises display device, wherein: described display device is connected with described pressure comparator with described current control unit respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320588762.9U CN203926173U (en) | 2013-09-24 | 2013-09-24 | Hoist fine motion control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320588762.9U CN203926173U (en) | 2013-09-24 | 2013-09-24 | Hoist fine motion control system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203926173U true CN203926173U (en) | 2014-11-05 |
Family
ID=51821992
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320588762.9U Expired - Lifetime CN203926173U (en) | 2013-09-24 | 2013-09-24 | Hoist fine motion control system |
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| Country | Link |
|---|---|
| CN (1) | CN203926173U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112639298A (en) * | 2019-03-06 | 2021-04-09 | 日立建机株式会社 | Construction machine |
| CN113800415A (en) * | 2021-09-24 | 2021-12-17 | 徐工集团工程机械股份有限公司建设机械分公司 | Self-adaptive control method of hoisting system of crane |
-
2013
- 2013-09-24 CN CN201320588762.9U patent/CN203926173U/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112639298A (en) * | 2019-03-06 | 2021-04-09 | 日立建机株式会社 | Construction machine |
| CN112639298B (en) * | 2019-03-06 | 2023-02-21 | 日立建机株式会社 | Construction machine |
| CN113800415A (en) * | 2021-09-24 | 2021-12-17 | 徐工集团工程机械股份有限公司建设机械分公司 | Self-adaptive control method of hoisting system of crane |
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|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20141105 |
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| CX01 | Expiry of patent term |