CN202100437U - Compressor unit speed adjustment control system - Google Patents
Compressor unit speed adjustment control system Download PDFInfo
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- CN202100437U CN202100437U CN2011201948766U CN201120194876U CN202100437U CN 202100437 U CN202100437 U CN 202100437U CN 2011201948766 U CN2011201948766 U CN 2011201948766U CN 201120194876 U CN201120194876 U CN 201120194876U CN 202100437 U CN202100437 U CN 202100437U
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Abstract
The utility model relates to a compressor unit speed adjustment control system, belonging to the technical field of automated control of a compressor unit, in particular to the compressor unit speed adjustment control system with a low failure rate of system operation and low cost of long-period operation. The compressor unit speed adjustment control system comprises a speed sensor, a controller, an electro-hydraulic converter, a pilot oil valve servo motor and is characterized structurally in that the controller is respectively connected with the speed sensor and the electro-hydraulic converter, and the electro-hydraulic converter, the pilot oil valve servo motor and a turbine valve are sequentially connected; the speed sensor is used for measuring speed signals of a rotor and transmitting the speed signals to the controller; and the controller is used for receiving the signals of the speed sensor, comparing the signals with a preset value for PID (proportional-integral-derivative) operation, and outputting speed adjustment control signals, the speed adjustment control signals are converted into secondary oil pressure signals through the electro-hydraulic converter, and the opening of the turbine valve is controlled by the pilot oil valve servo motor so as to control the flow rate of steam flowing into a turbine.
Description
Technical field
the utility model belongs to the compressor bank technical field of automatic control, relates in particular to a kind of compressor bank rotational speed regulation control system.
Background technique
In
modern petroleum chemical engineering industry, large-scale compressor equipment is the key equipment that drives the flow process running, is the heart of explained hereafter device.Safety in production is the energy-conservation of maximum, and the optimization control of compressor bank control system reliability, compressor bank controlling schemes, compressor bank body is to device operation and energy-saving and cost-reducing significant.
compressor speed regulating control is the core of turbocompressor group control, and traditional control needs a plurality of discrete instrument such as electronic speed regulator, interlocks from realizations such as insurance system, load controllers.Each discrete instrument all needs manual operation, and connection between each system and rate of fault height, and the long-term operation cost of whole system is very high like this.
Summary of the invention
the utility model is exactly to the problems referred to above, provides a kind of system operation troubles rate and long-term operation cost low compressor bank rotational speed regulation control system.
for realizing above-mentioned purpose, the utility model adopts following technological scheme, and the utility model comprises speed probe, controller, electro-control converter, pilot valve oil engine; Its structure outline controller links to each other with speed probe, electro-control converter respectively, and electro-control converter, pilot valve oil engine, steam turbine valve link to each other successively.
said speed probe is measured the tach signal of rotor and is sent into controller.
said controller receives signals of rotational speed sensor and setting value is relatively carried out PID (PID) computing; Output speed regulating control signal converts the secondary fuel injection pressure signal into through electro-control converter, gets into the steam flow of steam turbine through the aperture control of pilot valve oil engine regulating and controlling valve.
as a kind of preferred version, the said controller of the utility model adopts triplex level redundancy (TMR) controller (like the T6300 controller).
as another kind of preferred version, the current signal that the said speed regulating control signal of the utility model is 4-20mA.
as another kind of preferred version, the funtion part of the said controller of the utility model comprises the input part of testing the speed, hypervelocity blocking and hypervelocity prevention part, critical velocity problem part, speed loop decoupling zero part, boot sequence part, valve position restricted part.
as another kind of preferred version, the said input part of testing the speed of the utility model receives two tach signals that speed probe provides, and imports all just often when two tach signals, and tach signal is hanged down choosing; If a tach signal input fault, choose another velocity amplitude and input fault is reported to the police; If two tach signals import equal fault, carry out and close or speed loop is switched to manually-operable and input fault is reported to the police.
As another kind of preferred version, the said hypervelocity blocking of the utility model prevents part to detect the spinner velocity of compressor with hypervelocity, if the spinner velocity of compressor surpasses the hypervelocity blocking that pre-sets, then carries out compressor and closes
.
as another kind of preferred version, the said critical velocity problem of the utility model is partly through virtual switch override control critical velocity.
as another kind of preferred version, the said speed loop decoupling zero part of the utility model satisfies technological requirement through the speed of tandem regulating and controlling compressor or the aperture of inlet modulating valve.
secondly, the said boot sequence of the utility model partly provides automatic, semi-automatic and three kinds of start modes of manual starting.
in addition, the output signal or the valve of the said valve position restricted part of the utility model restriction actuator are cut the position, the output of the output of valve position restricted part and speed/load, auxiliary control channel carries out that signal is low to be selected.
the utility model beneficial effect: (1) the utility model is speed probe, controller, and electro-control converter, the pilot valve oil engine combines through PID control, has reduced system's operation troubles rate and long-term operation cost.
The high redundancy fault-tolerant control system of
(2) reliability.The utility model adopts triplex level redundancy TMR controller, has improved the reliability of system.
(3) integrated s operation control through controller makes that the speed regulating control speed of response is fast, the response sensitivity is high.When nominal situation, the rotating speed deviation that makes compressor is in claimed range; Under critical operating mode, valve or throttle are regulated in quick closedown, make the unit quick shutdown.
(4) the utility model speed regulating control signal is the current signal of 4-20mA; Laser propagation effect is good.
Description of drawings
further specify the utility model below in conjunction with accompanying drawing and embodiment, and the utility model protection domain not only is confined to the statement of following content.
Fig. 1 is the utility model schematic block circuit diagram.
Fig. 2 always schemes for the utility model speed adjustment system logic.
Fig. 3 is the utility model the 3rd warming-up control logic figure.
Fig. 4 is the overtime computational logic in the utility model second critical zone.
Fig. 5 is the utility model integral coefficient computational logic.
Fig. 6 is the utility model rotating speed PID arithmetic logic.
Embodiment
are as shown in Figure 1, and the utility model comprises speed probe, controller, electro-control converter, pilot valve oil engine; Controller links to each other with speed probe, electro-control converter respectively, and electro-control converter, pilot valve oil engine, steam turbine valve link to each other successively.
said speed probe is measured the tach signal of rotor and is sent into controller.
said controller receives signals of rotational speed sensor and setting value is relatively carried out the PID computing; Output speed regulating control signal converts the secondary fuel injection pressure signal into through electro-control converter, gets into the steam flow of steam turbine through the aperture control of pilot valve oil engine regulating and controlling porthole.
said controller adopts triplex level redundancy (TMR) controller.
said speed regulating control signal is the current signal of 4-20mA.
What the utility model controller was detailed below
respectively controls funtion part: input (magnetic sensor < holes probe>input) part tests the speed (1): the utility model speed probe is that controller provides two tach signals, tach signal employing frequency detecting mode.Controller carries out configuration to select using required frequency signal to controller through control algorithm, converts thereof into actual speed through controller again, when two speed inputs all just often, rate signal adopts the low mode of selecting.If an input fault is chosen the maximum value in another velocity amplitude.If all test the speed input fault, according to application, execution is closed or speed loop is switched to manually-operable, and all reports to the police for any fault.
Blocking of
(2) hypervelocity and hypervelocity prevention part: detect the spinner velocity of compressor,, then carry out compressor and close if the spinner velocity of compressor surpasses the hypervelocity blocking that pre-sets.When compressor reached the hypervelocity value that has been provided with, the hypervelocity FT function test was provided in order to prevention of checking hypervelocity and hypervelocity blocking function.Adopt to report to the police with show/the warning compressor speed moved to pre-set limit below or more than, and provide low, low-low and high, height-high parameter.The overspeed protection function that the control system of the utility model controller uses professional over speed protection and speed regulator itself to carry realizes hypervelocity blocking and hypervelocity prevention jointly.
(3) critical velocity problem part: compressor has one or several critical velocity with harmonic frequency or resonant frequency vibration usually.The speed set point function allows the definition to two critical speed range.If speed set point is in critical speed range, it passes the time that critical range is moved in critical speed range with minimize compressor with predetermined critical velocity slope inclination.If compressor can not reach a high side (because steam undersupply) of critical range, then speed set point will be reduced to low side of critical range automatically.If speed by PID is in manually-operable, then switch to automatic operation.
through being provided with virtual switch (having security features) but override control critical velocity function, satisfying the purpose of compressor test, but is performed in the normal operation period of being everlasting.
(4) speed loop decoupling zero part: satisfy technological requirement through the speed of tandem regulating and controlling compressor or the aperture of inlet modulating valve.Tandem control refers to adopt two-stage PID regulating loop, is respectively surge and regulates part and property regulation part two-part.
When
get into the surge adjusting when compressor; Sometimes the Properties Control part can require to reduce flow (when being inlet pressure like the Properties Control variable) simultaneously; Two control loops are mutual counteractive rotating speeds, thereby cause the instability of system, make unit more near surge.To this situation, the utility model Properties Control part and surge control device branch will output separately be weighted in the other side's the control mutually and go, thereby the realization decoupling zero is controlled and made two control loop coordinations.Properties Control partly through adopt leading-hysteresis decoupling zero condition with its control behavior with its on the same group the control behavior of loop (like anti-surge) coordinate mutually.
(5) boot sequence part: the utility model controller provides the selection of three kinds of different start modes: automatic, semi-automatic and manual starting.Must select a kind of of these three kinds of start modes during configuration, reach minimum speed control so that make from outage state.The minimum control rotating speed of the start mode of configuration and controller speed control system will depend on the start-up sequence and the makers' suggestion of factory.
if warming-up rotating speed (warming-up/the specified or automatic start mode of order) is set, controller will provide automatic rotating speed control and avoid critical speed of rotation.Can be through the keyboard of controller, the input of long-range contact.In addition, also can configuration the contact input of " allowing starting ".For example, if closing, tripping operation throttling or stop valve do not stop starting.
warming-up/specified: warming-up/rated functional makes operator between warming-up rotating speed that is provided with and rated speed, change rotating speed with the speed of configuration.Warming-up/rated functional can also configuration become only as rising to the rated speed function automatically.
Start automatically
: the order automatic starter function makes operator can start from the low warming-up rotating speed of setting and rest under this rotating speed until the warm-up period end of setting; Rise to the high warming-up rotating speed of setting then and stop and finish, rise to the rated speed setting value of setting at last until setting main high warm-up period.The waiting time and rate of acceleration under the warming-up rotating speed depends on " hot starting " or " cold start-up "." hot " and " cold conditions " by dead time confirm.When be in hot and cold condition between the time, speed control system is used and hotly to be confirmed suitable the starting speed and the waiting time with the interpolated value cold conditions data point.
if necessary can stop and the automatic start-up sequence of continuation order through programming and the self-drive time-out of employing order/continuation instruction.Can be through the keyboard of controller, long-range contact is imported and is selected to suspend or continue.In addition, the automatic starting of order can configuration become automatic pause at each warming-up setting value place.
(6) valve position restricted part: the valve position restricted part has limited the output signal or the valve of actuator and has cut the position, helps starting and shutdown.The low choosing of signal is carried out in the output of the output of valve position restricted part and speed/load, auxiliary control channel.Keyboard, the restriction of external contact adjustment valve position so the valve position restricted part has just limited maximum valve location, and can be passed through in the control of minimum valve position or the position that valve position restricted part passage has been controlled valve.
The dynamic fault that
valve position restricted part can also be used for system searches.Cause that system is unstable if think the TSCS speed control system, adjustment valve position restricted part is with the position of manual control valve.When using the valve position limiter must be noted that by this way, must not let system reach dangerous operating point.
in the application of driven compressor compressor, speed control logic can provide compressor and the complete order/startup of compressor.In general, speed controlling is received a frequency signal, and to compressor the output signal is provided.The speed input has comprised single or redundant signals, can in controller, carry out selection/decision.
are as shown in Figure 3; When the utility model the 3rd warming-up starts; When actual speed arrives the 3rd warming-up rotating speed; IDLE (for the inner warming-up control function block that weaves) function block works and does comparison according to the 3rd warming-up setting rotating speed and actual speed, carries out pulse timing, and output is respectively: warm-up mode demonstration, warming-up countdown, current warming-up rotating speed.
are as shown in Figure 4, when the utility model second critical zone enables, when actual speed arrives critical speed of second order down in limited time, actual speed carried out reverse countdown in the critical speed of rotation interval, and the critical zone refers in the scope of critical speed of rotation upper and lower limit.When timing time exceeds the time of setting, output action starts reports to the police or jumps car.
are as shown in Figure 5, and the utility model is exported the input signal Ki of back as PID integral control part to the integral coefficient of pid function block with the piecewise function mode, configures minimum value, the maximum value of Ki then.Calculate actual speed and minimum value, the maximum value of setting speed discrepancy again.The initial sum of confirming piecewise function according to these 4 values stops the zone, and the actual change value of Ki calculates through PID_AD function block (piecewise function function block) according to the actual value of speed discrepancy.
are as shown in Figure 6; This PID is a modulating valve working control output function piece; As the ending function block of speed control system, set rotating speed through after a series of judgement, revising, come speed underlying parameter with the deviation of actual speed as valve opening.
are in the rotating speed critical zone; Amplify the growth rate of pid function block setting value SP, enlarge the deviation with actual speed, make Kp, Ki parameter adjustment paces strengthen; Valve is opened with fast speeds, makes actual speed pass through the critical zone with the fastest speed.
are selected through the hand of this function block realization rotating speed control automatically, under shutting down, adopt manual mode, make things convenient for the work of valve limiter.Open behind the machine fully by automatic control.
Programmed logic of explanation the utility model below
: the utility model overall logic is divided into four parts, is respectively: (1) interlock logic that opens, stops.Start and stop car interlock logic mainly is a preparatory work of carrying out the interlock logic control of PID speed governing arithmetic logic; Carry out the prerequisite logic; The main completion as follows worked: a. possesses the running state that starting state is judged steam turbine through start button and steam turbine, does to start for the speed governing program and prepares.
b. comes the hand that carries out of valve limiter is selected and interlocking automatically through the running state of button and steam turbine.
c. handles respectively for the internal logic restriction of open and close valve under manual state.
d. selects whether need do overspeed test and output control when startup command is effective.
The circumscription logic of
e. speed setpoint when raising speed, reduction of speed.
It is that the other security limitations of the basis of two orders is handled that
f. addressing rotating speed ascending, descending speed still continues in interruption.
g. hypervelocity starts down jumps the car logic.
Button to HMI after
h. steam turbine starts all locks.
(2) rotating speed input processing logic.Rotating speed input processing logic is to confirm actual speed for PID speed governing arithmetic logic.Detect actual speed, two holes probes are carried out internal logic handle normalizing, convert the actual speed that program needs to.It is judged 3 warning outputs of realization, and they are respectively: the holes probe fault of a speed probe of a..
The holes probe fault of
No. two speed probes of b..
The whole faults of holes probe of
two speed probes of c..
(3) rotating speed arithmetic logic.Realize warming-up rotating speed and time, critical zone judgement, dead time, rated speed district decision logic in the rotating speed arithmetic logic.After the system operation with dead time initial value be changed to the cold conditions warm-up period; Simultaneously the compressor emergency shutdown time being carried out reverse countdown calculates; According to steam turbine outage state and cold conditions warming-up set forth, timer internal calculates the warm-up period that opens the machine needs next time, sets according to the input of the cold conditions warming-up that configures, hot warming-up and each warm-up period, the warm-up period that derives from dead time is calculated; Dead time, cold conditions time, three parameters of hot time are calculated comparison; Judge the span of intermediate parameters, in selected each the good warm-up period of basis, each the actual warming-up rotating speed and the time of calculating actual demand respectively; Carry out timeout treatment according to the input of critical speed of rotation and the actual speed of relatively calculating of actual speed simultaneously in the time of critical zone in the logic of rotating speed critical zone, judging whether needs to shut down or reduction of speed.
(4) PID adjusts arithmetic logic.PID adjusts arithmetic logic, during compressor steam regulation flow, need to consider two basic application, like this no matter load variations to the influence of driven compressor equipment how, compressor will move with required speed.For certain the pressure/flow in the application of maintenance process, adopt pressure/flow to speed tandem controlling schemes usually, and speed must change to reach process need continuously.
except that elementary object, compressor speed control has also comprised overspeed protection and critical velocity problem.Fig. 2 has shown automatic startup and closing sequence control.In addition, the control task that some are auxiliary like the valve location of single valve compressor, also can be carried out through speed control loop.Speed control loop also can be used as the signal source that rate signal is provided for other compressor control application.This part is accomplished the body of work of speed regulating control, comprises the steps: that a. at first carries out import-restriction control to each speed setting values such as jiggering rotating speed, rated speed, the warming-up of the utility model compressor are critical.
b. is in first and second critical zone during rotating speed, and is too high when the compressor shaft vibration that vibration measuring system detects, and automatically speed setting value dropped to the setting value place of input last time.
C. is after warming-up rotating speed enable data is selected, and PID setting value SP limitation function piece comes into operation, and can not be set in the rotating speed critical zone such as SP, when rotating speed is very low, can not SP be set at rated speed or hypervelocity rotating speed or the like.
When
d. hypervelocity enabled, to the logical process of speed setting with rated speed, the speed setting upper limit, the while speed setting value must be avoided critical zone (the concrete speed in critical zone derives from the parameter of dispatching from the factory of compressor bank).
e. demarcates in the logic at valve stroke, at first confirms the upper and lower limit and the stroke percentage of valve stroke.Again revise the upper and lower limit of valve after according to the actual demarcation state of open and close valve and valve feedback ratio.
f. is opening under the machine state, automatically through the valve restricted part valve is amplified to the demarcation upper limit of valve, and movement speed is adjusted according to timer internal.Opening under the machine state, when transferring manual control to, automatically valve position is being limited percentage and be controlled in the allowed band, avoiding the rotating speed disturbance excessive.
g. is in the adding of speed setting value, reducing; Manually be divided into crawl and linkage status; Rotating speed rises with the action of given rotating speed setting percentage during crawl, recently judges according to timer and percentage during interlock, increases rotating speed with certain speed.To avoid the critical speed of rotation district simultaneously, can be through specified button settings rotating speed to rated speed.
h. is after sequential control logic is effective, and speed setting value is raised to rated condition with rotating speed automatically according to the selection of each warming-up rotating speed.
The climbing of
i. speed setting value, rate of descent calculate.
Kp of j.PID, the logical process of Ki slope controller.
k. arrives pid function block with ready-made each parameter assignment in the above-mentioned steps.
are with being appreciated that; More than about the specific descriptions of the utility model; Only be used to the utility model is described and be not to be subject to the described technological scheme of the utility model embodiment; Those of ordinary skill in the art should be appreciated that still and can make amendment or be equal to replacement the utility model, to reach identical technique effect; As long as satisfy the use needs, all within the protection domain of the utility model.
Claims (3)
1. compressor bank rotational speed regulation control system comprises speed probe, controller, electro-control converter, pilot valve oil engine; It is characterized in that controller links to each other with speed probe, electro-control converter respectively, electro-control converter, pilot valve oil engine, steam turbine valve link to each other successively;
Said speed probe is measured the tach signal of rotor and is sent into controller;
Said controller receives signals of rotational speed sensor and setting value is relatively carried out the PID computing, and output speed regulating control signal converts the secondary fuel injection pressure signal into through electro-control converter, gets into the steam flow of steam turbine through the aperture control of pilot valve oil engine regulating and controlling valve.
2. according to the said compressor bank rotational speed regulation of claim 1 control system, it is characterized in that said controller adopts the triplex level redundancy controller.
3. according to the said compressor bank rotational speed regulation of claim 1 control system, it is characterized in that said speed regulating control signal is the current signal of 4-20mA.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011201948766U CN202100437U (en) | 2011-06-10 | 2011-06-10 | Compressor unit speed adjustment control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011201948766U CN202100437U (en) | 2011-06-10 | 2011-06-10 | Compressor unit speed adjustment control system |
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| Publication Number | Publication Date |
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| CN202100437U true CN202100437U (en) | 2012-01-04 |
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ID=45386452
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011201948766U Expired - Fee Related CN202100437U (en) | 2011-06-10 | 2011-06-10 | Compressor unit speed adjustment control system |
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| Country | Link |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102392813A (en) * | 2011-06-10 | 2012-03-28 | 辽宁华兴森威科技发展有限公司 | System for adjusting and controlling revolving speed of compressor unit |
| CN104428755A (en) * | 2012-07-24 | 2015-03-18 | 通用电气公司 | Systems and methods for control reliability operations |
| US9665090B2 (en) | 2012-07-24 | 2017-05-30 | General Electric Company | Systems and methods for rule-based control system reliability |
| US9912733B2 (en) | 2014-07-31 | 2018-03-06 | General Electric Company | System and method for maintaining the health of a control system |
-
2011
- 2011-06-10 CN CN2011201948766U patent/CN202100437U/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102392813A (en) * | 2011-06-10 | 2012-03-28 | 辽宁华兴森威科技发展有限公司 | System for adjusting and controlling revolving speed of compressor unit |
| CN102392813B (en) * | 2011-06-10 | 2015-10-14 | 辽宁华兴森威科技发展有限公司 | Compressor unit speed adjustment control system |
| CN104428755A (en) * | 2012-07-24 | 2015-03-18 | 通用电气公司 | Systems and methods for control reliability operations |
| US9665090B2 (en) | 2012-07-24 | 2017-05-30 | General Electric Company | Systems and methods for rule-based control system reliability |
| CN104428755B (en) * | 2012-07-24 | 2017-09-12 | 通用电气公司 | The system and method operated for control reliability |
| US9912733B2 (en) | 2014-07-31 | 2018-03-06 | General Electric Company | System and method for maintaining the health of a control system |
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| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120104 Termination date: 20160610 |
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| CF01 | Termination of patent right due to non-payment of annual fee |