CN1093646C - Plant control system and process controller - Google Patents

Abstract

To provide the controller which can optionally recombine input and output points of operation terminal drive modules corresponding to a variety of auxiliary machines without fixing them. A PDCM(operation end drive module) attached to a controller 100 for control is provided with a CPU 202, a nonvolatile memory 203, and a serial I/F 204 and sends and receives serial signals to and from relative equipments of an object auxiliary machine. The memory 203 of the PDCM 200 is stored with programs for a protecting function, etc., characteristic of an operation terminal and the CPU 202 holds the operation terminal 500 at the time of downloading of the controller 100. Further, if an air source 510 is abnormal, the operation terminal is operated to a fail-safe side (fully open/ fully closed). The input and output points of the PDCM 200 are not fixed in terms of hardware, so a function can optionally be extended or changed.

Description

Apparatus control system and process controller

The present invention relates to a kind of apparatus control system, particularly a kind of method and peculiar disposal route of a kind of final control element (in check process component) that process controller is linked to each other with process component.

Recently, be used for the control system of large-scale equipment, be extensive use of dcs, wherein each of a plurality of procedures systems is basically by an independent control computer control.For example, be used for the control system of cogeneration plant, be each key facility,, providing a plurality of process controllers that monitored by a principal computer as steam generator system, turbine system, generator system etc.Therefore, realized improvement Steam Generator in Load Follow performance, and satisfied strict regulations to the air emission gases.

In general, each a plurality of process controller of directly controlling one group of process component is connected on each system master system device.Because each process controller comprises a processor (CPU), and control one group of process component simultaneously, so carry out the complicated control or the Optimal Control of equipment easily according to the result that processor is carried out.And this combination of controller also has the advantage that reduces the control system size or reduce the control system production cost.

Yet if a controller is controlled a plurality of elements, when in the part of the I/O in CPU or controller certain fault taking place, all elements of this controller management become uncontrollable, make to be difficult to the operation of the equipment of proceeding.

In order to overcome the above problems, applicant of the present invention has invented a kind of control method that drive control module (DCM) wherein is provided in Jap.P. publication 37845/1994 (list of references 1), and this method has been applied to the actual production of control system.In this method, controller is by using directly control one group of process component (comprising final control element) of a CPU, and for controller provides DCM, each of DCM is connected on each controlled element and controls controlled member separately, also comprise a modulus input/output end port and a back-up device that is used for keeping current control command value, so that occur among the convenient CPU can the controlled element of enough hand adjustment joints when unusual.And each DCM comprises a device, is used for the current control input value of pinning element when unusual when occurring in the element.

All process controllers of a main control unit and an existing apparatus control system are based upon in the element pulpit, avoiding the influence of on-the-spot side vibration of element, noise, high temperature and humidity etc., and by setting up on the process component that cable is connected to on-the-spot side.For example, in cogeneration plant, the distance between element pulpit and the field process element is tens to hundreds of rice.Therefore, because each final control element and instrument are connected on each controller, so number of cables is very big, this needs the more time to set up cable.Like this, the degree of freedom of improving control system is lower, or control system is maintainable relatively poor.As one of all methods that address this problem, JP-A-314505/1996 (list of references 2) discloses near the method each final control element that controller that a kind of handle is used for controlling each element is arranged in on-the-spot controlled member.

Owing in list of references 1 disclosed method, provide a DCM, can improve the reliability and maintainability of controller, so this method is widely used in the control system of generating plant by each element for controller control.Applicant of the present invention has improved this method; and in above-mentioned DCM, developed a kind of programmable control module (PCM); PCM comprises interface, a CPU and the nonvolatile memory with final control element; PCM has defencive function with operation auxiliary element when controller has fault; as at paper " up-to-date thermoelectricity is sent out technology " (RecentThermal Power Generation Techniques); Hitachi Hyoron; Vol.79; 1997/3, disclosed such among the pp29-30.

Process component by each DCM or each PCM control generally is called auxilliary element, and for example, final control element is as valve, pump, subsidiary component etc.Various instruments, as be used for detecting controlled variable and the performance variable relevant with final control element detecting device, be used for detecting valve standard-sized sheet or full cut-off limit switch, be used for monitoring and be included in the relay or the switch of the actuator of final control element in one group of subsidiary component.Sometimes, the input media that is used for importing the interlocking signal of necessary signal of manual adjustments or relevant final control element is included in one group of subsidiary component.And DCM or PCM not only control a final control element, but also control one group of collaborative each other final control element and its subsidiary component, for example lead the fluid stream of the common control of (large scale) valve and time (small size) valve by these valve controls.

If further add control or defencive function to improve the reliability and the controllability of control system, then increase the quantity of input/output point, promptly increase the quantity of cable.If the layout of input/output point is fixed in each DCM, the structure of control system and need to change input/output point is arranged among the DCM control system and improve and become complicated then.If improve, even for example have only the type change of terminal prot or instrument, need the increase or the minimizing of input/output point or rearrange, then be not easy to realize the improvement of control system, because a kind of like this improvement is accompanied by the connection variation of input/output point among the DCM and the work of setting up of on-site cable.In order to increase input/output point, it is inevitably that the connector of standard specification exchanges, and the connector of standard specification must be suitable for being used for the size of the instrument panel of drive control module.And the increase of connector size directly causes the size of controller to increase.

As for disclosed method in the list of references 2, owing to reduce total cable length by near each final control element each controller being installed, this method has the advantage that reduces the control system production cost.Yet this method causes a new problem, promptly must provide additional facilities, as the air conditioning chamber, protects controller to avoid the influence of on-the-spot rugged surroundings.Do not have air-conditioning if controller is installed in the scene, then crash rate increases.Therefore, owing to must reduce calculated performance or use special and expensive part by reducing clock frequency, to prevent the increase of crash rate, so this method is unpractiaca.

The objective of the invention is to address the above problem, and provide a kind of process controller, the wherein restriction of not controlled auxiliary element kind of the layout of input/output point and quantity in the drive control module, and can be adapted to the various combinations of controlled auxiliary element neatly, and a kind of apparatus control system that uses this process controller is provided.

In order to realize above purpose, the invention provides a kind of apparatus control system, by an a plurality of process controller and principal computers that are connected on the network on the network that are connected to are installed in the central member pulpit, come the control procedure element, each of process controller comprises final control element driver module, and each of module is connected at least one of process component through data transmission device.

Wherein said data transmission device be can be two-way the serial data signal transmitting device of execution serial conversion, by a serial data signal transmission line that in the serial data signal transmitting device, provides, import a plurality of data-signals of a plurality of data-signals/therefrom export to final control element driver module, a plurality of data-signals are included in the measured value of process variable on control command signal of a final control element of each process component and the process component.

And final control element driver module comprises: a nonvolatile memory that is used for storing a software, the peculiar function of the controlled final control element of this software processes (controlled process element); With one be used for being independent of the CPU that process controller is carried out this software; And be used for handling the necessary data of this function and be input to final control element driver module/therefrom output through the serial data signal transmission line.

Each final control element functions peculiar is for example to be used for carrying out maintenance operation and/or protection (interlocking) function of fail safe operation or the following Collaborative Control function of controlled final control element.

And, apparatus control system comprises near a remote cabling cartridge module (being referred to as RTB) that is installed in the process component, the remote cabling cartridge module comprise be used for carrying out bidirectional linked list/parallel data conversion and through the serial transmission device of serial data signal transmission line data-signal and be parallel-connected to instrument and the drive unit of controlled process element on be used for the input/output end port of I/O data-signal.

The remote cabling cartridge module comprises the hardware circuit of removing CPU and storer from conventional DCM, and the tolerance that this has just improved on-the-spot rugged surroundings makes it possible to a remote cabling cartridge module and is installed near the process component.

And, two kinds of remote cabling boxes can be provided, promptly, a kind of analog remote cabling cartridge module and a kind of being used for that is used for transmitting the analog data signal on the controlled process element with final control element driver module transmission of digital data signal, as activation signal, digital remote terminal box module, digital data signal is also through the serial data signal transmission line.In analog remote cabling cartridge module, an analog-digital commutator and a digiverter are provided in the analog remote terminal module.

In this embodiment, if provide a plurality of remote cabling cartridge modules, then utilize the multistation method remote cabling cartridge module that is linked in sequence corresponding to a large amount of input/output points or multiple signal.Like this, can easily adapt to the quantity increase of input/output point.According to the control cycle of equipment, determine the upper limit of I/O number of spots by the transmittability of serial data signal transmitting device.

And final control element driver module can be connected to the remote cabling cartridge module by dual serial data transmission line.Like this, further improved the reliability of control system.

If carry out by the collaborative Collaborative Control of carrying out of one group of final control element, to control concrete process variable, the CPU that in each final control element driver module, provides then, according to one group of program that is used for Collaborative Control of storing in the storer in final control element driver module, for each final control element calculates a control command value.As an a kind of like this example of Collaborative Control, known a kind of by a main flow valve and the bivalve Collaborative Control that inferior stream valve carries out with different openings size.And, carry out Collaborative Control by a plurality of make-up pumps sometimes with different supply capacity.

And, protect the program of collaborative final control element also to be stored in the storer for one group.CPU receives the data of the abnormal operation be used for monitoring each final control element through the serial data signal transmission line, if and in any one group of final control element, detected abnormal operation, the final control element of all or part then under the fail safe state, would be controlled.

And, in the present invention, a process controller that is used for the control procedure element has: a CPU and a plurality of final control element driver module on bus to the CPU that the control that is used for the implementation element is calculated, driver module is connected on the process component through data transmission device, this process controller comprises: a nonvolatile memory that in each final control element driver module, provides, can store the software of realizing each final control element functions peculiar with rewriteeing; With the 2nd CPU who in each final control element driver module, provides, be used for being independent of a CPU executive software; Wherein data transmission device is a serial data signal transmission line, and input or output a CPU through the serial data signal transmission line and carry out the necessary data of calculating and handle the necessary data of each final control element functions peculiar, this processing is carried out by the 2nd CPU.

Form the following effect of generation according to control system of the present invention.That is, because final control element driver module is through serial data signal transmission line and controlled process element transmission data, so the layout of the input/output point in each driver module be can't help the type or the fixed amount of driver module process component to be processed.Therefore, by in driver module, changing and be provided for the address of input/output end port, can freely realize the increase of input/output point/reduce or rearrange, and can also easily add the element functions peculiar.

For example, if the operating mistake of CPU ground stops in the process controller, by the software of implementation procedure element protection function is stored in the final control element driver module, then can keep the current operation status of final control element by control command from the CPU in the final control element driver module; And if the process component that comprises final control element becomes unusually, then final control element is operated the fail safe state.And, final control element group is not divided into each element and each is not distributed to a control circuit by using one group of final control element together, can carry out Collaborative Control.And, even add the peculiar function of process component, also needn't change the erecting cable between element pulpit and the device context.

By using a serial data signal order wire, can realize the erecting cable between each final control element driver module and the controlled process element through the remote cabling cartridge module.And, because under the situation that the I/O number of spots that is used for process component increases, need only increase the remote cabling cartridge module in addition, and utilize the multistation method of attachment can connect the remote cabling cartridge module that comprises interpolation one by one, so can solve the huge increase problem of required lead amount and installation work by the process controller that adopts this embodiment at all.

As mentioned above, according to the present invention, because being standardized into of process controller is possible, and can easily provide distinctive interlock function of final control element or Collaborative Control, so can improve control performance and reliability.And, owing to can reduce to set up between element pulpit and the device context the essential lead amount of cable significantly, become quite easy so build, improve or safeguard.

Fig. 1 is the block schematic diagram of apparatus control system according to an embodiment of the invention.

Fig. 2 represents to use an example of power-equipment of the present invention.

Fig. 3 represents the layout of factory building shown in Figure 2.

Fig. 4 represents to be used for monitoring and to control the supervision of whole factory building shown in Figure 2 and the composition of control system.

Fig. 5 represents the composition of a serial data signal transmission line and an example of its method of attachment.

Fig. 6 is the block schematic diagram of the RTB of an embodiment.

Fig. 7 A and Fig. 7 B represent the form of the serial data signal that transmits between PDCM and the RTB and handle the flow process of serial data signal transmission.

Fig. 8 A and Fig. 8 B represent the transmission method of I/O data-signal among the RTB, and are used for decryption address setting method.

Fig. 9 is a process flow diagram, is used for explaining an example of interlock process among the PDCM.

Figure 10 is the block schematic diagram that apparatus control system improves example, and wherein the serial data signal transmission is repetition.

Figure 11 is the block schematic diagram of the apparatus control system of another embodiment, wherein carries out Collaborative Control according to the present invention.

Figure 12 is a curve map, is illustrated in the flow control that is used for the total flow scope in the collaborative flow control and how is shared by the control of a small size (less important) valve and the control of a large scale (main) valve.

Figure 13 is a process flow diagram, is used for explaining the collaborative flow control of carrying out for by the control method shown in the apparatus control system shown in Figure 11 and Figure 12, an example of the interlock process of being carried out by PDCM.

Hereinafter will explain details of the present invention with reference to the embodiment shown in the accompanying drawing.

Fig. 2 represents a kind of composition of single axle combined cycle power plant, as an example using power-equipment of the present invention.A kind of combined cycle power plant comprises: one by a pneumatic plant, a turbine and the gas turbine that the firing chamber is formed; One is used for reclaiming the heat of discharging from gas turbine, and the heat that reclaims is delivered to the heat recovery boiler of steam turbine, and steam turbine utilizes a single shaft to be directly connected to gas turbine; With a generator; (these are called main element) and be used for operating main element or measure the auxiliary element of the mode of operation of main element.An operation valve shown in Fig. 2 is a final control element, and is one of auxiliary element that is used for by turbine.

Fig. 3 represents the layout in power station, and combined cycle power plant shown in Figure 2 wherein has been installed.In power station example shown in Figure 3, a generating set comprises four shaft devices, and constitutes the power station by two generating sets.The one side length of wherein building the place in power station is about 300 meters.And the device control cell that is used for each facility is based upon an element pulpit of close central control room usually.According to routine, the element pulpit is connected on the instrument of final control element or auxiliary element by each cable, the distance between element pulpit and element or the instrument is about tens to hundreds of rice.For example, in the Combined Cycle power station of 2 groups * four-axis mounting, existing several thousand cables of whole erecting cable system's needs.

Fig. 4 represents to be used for the roughly composition of the apparatus control system of cogeneration plant.Apparatus control system shown in Fig. 4 is represented as being used for one group of four-axis mounting.In central control room, a group control desk, a large scale screen, a group common control unit, a centralized maintenance docking station etc. have been arranged.In addition, the element pulpit is connected on the network in the group, and a shaft device principal computer, a control module that is used for each major component etc. are provided at the element pulpit.Process controller according to the present invention is applied to, for example, and gas turbine and steam turbine control module or a boiler control module, as shown in Figure 4.

Fig. 1 is the block schematic diagram of the apparatus control system of first embodiment, being connected between expression process controller and the auxiliary element that will be controlled by process controller.

Process controller 100 comprises a CPU 101, storer 102, PI/O (process I/O) interface 104 (being called I/F), and these devices are connected to each other by the bus in the controller.CPU 101 control major components, as boiler, all or part of operation.Usually, each process controller 100 has a transmission interface 103, and is connected on other process controllers.Like this, distribute control by these controllers 100.

And a plurality of drive control module 200-1 to 200-n extend bus 106 through a P I/O and are connected on the P I/O interface 104.Each drive control module 200 provides with the form of circuit board, and this circuit board comprises a P I/O interface being installed on the control stand 201, CPU 202, a storer 203 and a serial line interface 204.Storer 203 is rewritable non-volatile storeies, and stores the software (program) that realization is used for the defencive function of each final control element, and this is realized by a hardware circuit usually.Below, above-mentioned driver module able to programme 200 is called PDCM (drive control module able to programme).

Each PDCM of this embodiment is singly corresponding to a final control element of device context, and by a serial data signal transmission line 300 subsidiary component of final control elements and final control element is connected to PDCM.Therefore, provide serial line interface 204,, perhaps the serial data from 300 inputs of serial data signal transmission line is converted to parallel data so that the parallel data from CPU 202 outputs is converted to serial data.

As shown in fig. 1, serial data signal transmission line 300 is through a RTB (remote cabling box) and the auxiliary element transmission data that comprise final control element.And, as shown in Figure 5, serial data signal transmission line 300 comprises a twisted-pair cable serial cable and two twisted-pair cable connectors 302 and 303 that are connected to the twisted-pair cable both end sides, and by using connector 302 and 303 that the PDCM in the element pulpit 200 is connected on the RTB 400.Like this, and wherein the squash type terminal is connected to the lead that is used for each input/output point and with screw lead fixed is compared with maintenance work to the routine wiring on each input/output terminal, installation work and maintenance work become than being easier to.

Only, just can easily realize dual serial data signal line by adding other cable 301 and connector 302 and 303 of a cover.If the dual serial data signal line of each root is installed with different routes, then can be accident, as fire, earthquake etc., the damage that causes is restricted to one that has only all lines, makes that recovering the control system ratio is easier to.

By using a serial twisted-pair cable, can be transmitted in a plurality of data item that receive parallel/serial conversion in the transmittability scope of determining by a control computation period.And, if because the input/output point that is used for the auxiliary element that will control is in a large number arranged, use a plurality of remote cabling boxes as requested, RTB 400-1 as shown in Figure 1 and RTB 400-2, then because these RTB utilize the multistation method of attachment to be linked in sequence, be used for Connection Element pulpit and on-the-spot serial data signal transmission line so needn't add one.To explain the composition of RTB 400 in detail below.

The auxiliary element that will control shown in Figure 1 comprises the flowrate control valve 500 that its final control element is a pneumatic control valve and the subsidiary component of flowrate control valve 500.An electric pneumatic converter (E/P) 503 is by using the air-flow of being supplied with by pneumatic supply 510 with the electromagnetism cut-out governing of the proportional motion of current value (E), the control command current value (E) that is used for performance variable 1. a passage of the simulation output from RTB 400-1 is exported converts the air pressure (P) corresponding to current value (E) to.Also supply with air pressure to the pneumatic-position transducer (P/P) 502 of a valve, and converter P/P 502 is adjusted to a valve position corresponding to conversion air pressure (P) to the opening of valve 500 from pneumatic supply 510.Detect the valve opening of final control element by a valve opening detecting device 507 that is provided at converter P/P 502 places, and the passage that the valve opening that detects is input to analog input part (AI) 2..And by the cross range of flow of a flowmeter 501 measurements by final control element control, and 3. a flow that records is input to an AI passage partly.

A limit switch (SW) detects the standard-sized sheet or the full cut-off of final control element, and the passage that the signal that detects is input to digital importation among the RTB 400-2 6..And, be used for monitoring that pressure by air pressure switch 508 and 509 monitors two air mass flows from pneumatic supply 510 respectively, 7. and 8. and if pressure abnormity reduces (air loss), then the passage separately of giving a digital output (DI) the pressure abnormity signal.The interlocking signal imperative operation solenoid valve of operation (EMV) 504 that a passage of a digital output (DO) is 4. exported from RTB 400-2 is to open or close final control element 500 fully.And opening of a holding signal operation of 5. exporting from a passage keeps EMV 505, to keep the open front of working as of final control element 500.

Fig. 6 represents the composition of the RTB of an embodiment, is used for transmission of analogue signal and digital signal.In this embodiment, RTB has a kind of composition, wherein from disclosed conventional control module, for example in list of references 1 and 2, remove by a CPU and the function that storer is finished, and form by hardware circuit for an interface function of the element that will control.And RTB installs near controlled member.

RTB 400 comprises: a serial line interface (I/F) 401, be used for the data through 300 transmission of serial data signal transmission line are converted to serial data from parallel, and vice versa, (P  S: bi-directional conversion); An address setting circuit 402 of all signals, management RTB 400; And an oscillator 403, be used for the clock signal of output function RTB 400.

RTB 400 is connected on the subsidiary component of a controlled auxiliary element through a terminal interface 420, and receives the DI signal that its level is changed by a level converter 407.And the AI signal receives through one second converter 408, and is transformed into numerical data by 406 and A/D converters 405 of a multiplexer (MPX).And these input data convert serial data signal to through serial i/F 401 again, and address setting circuit 402 is provided with an address for each data-signal.And, export to serial data signal transmission line 300 at the serial data signal that presets the conversion of timer time handle.

In addition, if be linked in sequence a plurality of RTB, then in the serial data signal that is received by serial i/F 401, only the Data Receiving that its address is assigned to the RTB 400 that comprises serial i/F itself is advanced among the RTB 400.After in a single day each DO signal is latched at the corresponding address place of a latch cicuit 411, the DO signal, for example interlocking signal etc. just outputs to corresponding controlled member through a level converter 412 and a terminal prot 420.A control command to final control element converts simulating signal to by a D/A converter 413, and is selected by a multiplexer DE-MPX 414.And the simulating signal of choosing is amplified by an amplifier 415, and as an AO signal output.Simultaneously, as shown in fig. 1, if different RTB shares transportation simulator data-signal and digital data signal respectively, then each RTB must only have corresponding of all above-mentioned functions.

Above-mentioned signal input in RTB 400 handles and output is handled, respectively by an input control circuit 404 and output control circuit 410 controls.The clock signal step-by-step operation of control circuit 404 and 410 by exporting by oscillator 403, and according to presetting the operation of carrying out each circuit in proper order.Although utilize process controller 100 can non-synchronously carry out the operation of RTB 400,, synchronously be adjusted in the signal transmission cycle of carrying out among all RTB that are linked in sequence according to the control cycle of process controller 100.Simultaneously, because RTB 400 and the parts and the circuit that provide at RTB 400 places do not comprise software, so even in high temperature, dust or the noise circumstance of device context, the also rare fault of RTB 400.

As mentioned above, owing to do not have the hardware of CPU and storer to form, realize the RTB of present embodiment, so improved the environment tolerance of RTB by employing.Therefore, do not provide the air conditioning chamber just can set up RTB near the controlled member at the scene.And, owing to utilize the multistation method of attachment, can add RTB, so can easily increase the quantity of input/output point according to customer requirements by the RTB that adds is sequentially connected on the existing RTB.Like this, the variation of circuit becomes more flexible among the structure of control system or improvement and the RTB.

As follows, will explain the operation of the apparatus control system of first embodiment.At first, explain the transmission process of serial data signal.Fig. 7 A and Fig. 7 B represent the form of serial data and the flow process of transmission process respectively.As shown in Figure 7A, in serial data signal, after the data block that comprises a beginning flag, process data, an address, an abnormality mark and an end mark, add one by being inverted the inversion serial data signal piece that front serial data signal piece obtains.Between PDCM 200 and RTB 400, the special-purpose LSI by using in the serial i/F 204 of mutual alternate data signal and serial i/F 401 carries out data transmission and processing (being called the alternate data transmission).

As shown in Fig. 7 B, PDCM 200 handles in step 101 beginning data signal transmission, forms the serial data signal that will send in step 102, and in step 103 this serial data signal is sent to RTB 400.When RTB 400 when step 104 receives serial data signal, carry out the data-signal receiving course, wherein carry out the reasonableness test that receives serial data signal in step 105.When reasonableness test, step 1051 be inverted data-signal comparison process, check abnormality mark, and determine interruption status.If the data-signal that receives is normal, then data-signal is transferred to an appropriate address in step 1052, otherwise, abandon this data-signal in step 1053.After this step, begin automatically to send a data-signal from RTB 400 to PDCM 200 with the alternate data transmission in step 106.RTB 400 forms a serial data signal that will send in step 107, and in step 108 this serial data signal is sent to PDCM 200.When PDCM 200 when step 109 receives the serial data signal of transmission, carry out and the identical reasonableness test that carries out in step 105, and if the serial data signal that receives normal, then data-signal is received an appropriate address in step 110.

Fig. 8 A and Fig. 8 B are used for explaining the address are set.If utilize a kind of serial data signal transmission method that PDCM 200 is connected on the RTB 400, the address of a data-signal I/O then is set, for example shown in the table among Fig. 8 B.That is, the OPADD 1 and 2 that sends to RTB 400-1 from PDCM 200 is the OPADD that are used for RTB (1) output 1 and 2, is illustrated among Fig. 8 B.For example, output data address 1 is corresponding to the control command value that is used for a final control element.Do not use output data address 3 and 4, and give over to blank.On the other hand, the Input Address 1 and 2 that sends to PDCM 200 from RTB 400-1 is the Input Address that are used for RTB (1) input 1 and 2, is illustrated among Fig. 8 B.For example, input data address 1 is corresponding to the measured value of a process variable.

An address is set for each serial data signal according to above-mentioned address corresponding tables, and sends serial data signal by the order of address.Usually, because AI is become the long number data with the AO analog signal conversion, a data-signal corresponding to an address is set in a frame of serial data signal.On the other hand, with regard to DI and DO digital signal, the various numerical datas corresponding to a plurality of addresses are set in a frame of the serial data signal of being everlasting.

Fig. 9 represents the treatment scheme by the protection operation of PDCM 200 execution.One is used for finishing in the storer 203 of procedure stores in PDCM 200 of protection operation, and is carried out by CPU 202.If normally carry out common automatic control, then CPU 202 carries out following process at each control cycle.

At first, be used to refer to by check in step 201 process controller 100 normal running, from the signal that CPU 101 sends out, whether the operation of decision process controller 100 normal.If normal,, carry out the diagnosis of RTB normality for the valve opening signal of measuring then at the measured value of step 202 by check valve opening detecting device 507.The diagnosis of RTB normality is equivalent to above-mentioned each and receives the reasonableness test of serial data signal.If valve opening signal is normal, then at step 203 test valve 500 whether according to the correct operation of its control command value.If this valve is correctly operated, then in step 204 by check from the signal that the limit switch 506 of the valve opening that is used for final control element 500 sends, carry out the diagnosis of RTB normality for the signal of limit switch 506.If this signal is normal, check in step 205 whether the signal of limit switch 506 indicates normal condition (assignment 1 or 0).If this signal indication normal condition is then passed through check from air pressure monitor pressures switch 508 and 509 measured values that send in step 206, diagnose for carrying out RTB normality from the measured values of air pressure monitor pressures switch 508 and 509 transmissions.If this measured value is normal, then check in step 207 whether air pressure is normal.If normal, then finish the processing of this control cycle.

On the other hand, if be used to refer to the signal indication " unusually " of controller normal running, judge that then controller is unusual, and export an opening holding signal in step 208 in step 201.Like this, the opening of final control element 500 keeps EMV 505 to remain by opening and works as open front, and makes manual operation mode become possibility in step 211.And, if indicate " unusually " (2.), judge that then RTB is unusual at the RTB normality diagnostic result of step 202 execution, and at interlocking signal of step 209 output.Like this, go up the final control element 500 of operation by imperative operation EMV 504 in fail safe direction (standard-sized sheet or full cut-off).And, if, then judge final control element 500 for unusual, and export an interlocking signal in step 210 in step 203, any one place indication " unusually " of 205 and 207.Like this, go up the final control element 500 of operation, and can prevent the generation or the expansion of accident in fail safe direction (standard-sized sheet or full cut-off).

As mentioned above, when process controller had fault, the CPU 202 in the PDCM 200 controlled independently and calculates and the finally interlocked operation of control element.In above-mentioned processing, can carry out RTB normality diagnosis etc. by the special-purpose LSI that is provided in serial i/F 204.And, on the CRT in centralized maintenance docking station shown in Figure 4, show a circuit that is equivalent to the defencive function of realizing by saved software in the storer 203, this defencive function can be seen, and the operation of this defencive function can be easily monitored.

According to above-mentioned first embodiment, by adopting the serial data signal transmission method, it is unfixed that the input/output point in the PDCM is arranged.Therefore, by freely arranging the input/output point in the PDCM, can corresponding various functions, as interlocking, maintenance etc., its each function all is distinctive for each final control element, and can design control system neatly.And, owing to utilize multistation method of attachment a plurality of RTB that can be linked in sequence, so the variation of the type of the quantity of the input/output point of corresponding controlled auxiliary element or final control element or instrument neatly.Like this, owing to by a serial data signal transmission line PDCM is connected on the on-the-spot final control element basically, so can significantly reduce the cable amount that to use.

Nature, the quantity that connects the serial data signal transmission line of PDCM and auxiliary element is not limited to one.As former explanation, can use dual serial data signal transmission line.And in apparatus control system, the surveying instrument of process variable realizes that by a dual instrument system to avoid losing fully of process data measurement function, this situation has a strong impact on apparatus control system.

Figure 10 represents the block schematic diagram of the apparatus control system of another embodiment, and wherein PDCM is connected to auxiliary element by many serial data signal transmission lines.Be with the difference of first embodiment shown in Figure 1, each variable (AI) of measuring by dual process flow detector 501a and 501b through special-purpose separately RTB 400-1 and 400-2, and separately PDCM 200-1a and 200-1b be input to process controller 100.

In this embodiment, all input/output signals relevant with controlled auxiliary element be can't help PDCM and are handled, and the special-purpose PDCM that is used for handling signal specific provides separately, and is connected to each special-purpose RTB through each root dedicated serial data signal transmission wire.Even in this embodiment, compare with the conventional equipment control system, also significantly reduce the cable amount, and can guarantee the reliability of apparatus control system.And owing to carry out concrete defencive function by PDCM, and the layout of the essential input/output point of defencive function do not fix, so can be neatly corresponding to the variation that improves or increase function or controlled auxiliary element type.

By duplicating the serial data signal transmission line,, use other single line also can carry out the function of using abnormal wire to finish even the unusual of line interruption and so on takes place in a copied line (main line).If set up each root copied line for the following accident of defence with different routes, then further improved the reliability of apparatus control system.According to this embodiment, owing to significantly reduced the cable amount, and input/output point is not fixed the possibility so above-mentioned redundant system composition becomes.

As follows, with a kind of apparatus control system of explaining according to second embodiment of the invention.In first embodiment, PDCM is corresponding to a controlled auxiliary element, and the control command of being calculated by process controller 100 outputs to corresponding final control element through this PDCM.Yet sometimes, a control function cooperates realization by a plurality of final control elements.For example,, must provide a large scale valve (main valve) and a small size valve (inferior valve) in order to control whole large-scale flow exactly, and these two valves of co-operating.Explanation in passing, in the thermal power plant of burning coal, certain tittle is by three valve Collaborative Control.

According to routine, for a kind of like this Collaborative Control, process controller calculates each control command of one group of collaborative final control element that is used for a control function, and through each drive control module output.That is, although control a control function, the final control element group that is used for realizing this control function is divided into element separately, each distributes to each moving control module it.In this embodiment, the above-mentioned Collaborative Control of by following execution a control function being carried out by a PDCM.

Figure 11 represents a kind of block schematic diagram of apparatus control system, wherein carries out the bivalve Collaborative Control.Although the basic composition of control system is identical with control system shown in Figure 1, two final control elements are controlled by PDCM, i.e. a large scale valve 600 and a small size valve 700.The subsidiary component of each valve is not shown among this figure, but these subsidiary components almost are equivalent to shown in Figure 1 those.

When PDCM 200 when process controller 100 receives the control command of total flow, PDCM 200 carries out a bivalve Collaborative Control program, and, control large scale valve 600 and small size valve 700 by exporting an opening order to each valve through serial data signal transmission line 300 and RTB 400-1 to 400-4.RTB 400-1 (AI/O) and RTB 400-2 (DI/O) are connected on the subsidiary component of large scale valve 600 and valve 600, and RTB 400-3 (AI/O) and RTB 400-4 (DI/O) are connected on the subsidiary component of small size valve 700 and valve 700.

PDCM 200 also carries out the calculating that is used for controlling the interlocking logic except that carrying out above bivalve Collaborative Control, and protects equipment when need opportunity.So, the process that is used for bivalve Collaborative Control and interlocking logic as procedure stores at storer.

Figure 12 represents an example of operating characteristic in the bivalve Collaborative Control.If require flow less than 50%, the opening that then has only small size valve 700 flow on request is operated pro rata, and closes large scale valve 600 fully during this control model.On the other hand, if the flow that requires is equal to or greater than 50%, then opens small size valve 700 fully, and have only the opening flow on request of large scale valve 600 to be operated pro rata.In this embodiment, PDCM is according to the main control order from process controller 100 outputs, be the opening requirement that large scale valve 600 and small size valve 700 calculate separately, and separately opening requirement outputed to each valve 600 and 700 by the serial data signal transmitting device.Like this, for 0 to 100% scope Control Flow accurately.

Figure 13 represents the middle processing interlocking logic flow of carrying out embodiment illustrated in fig. 11.If control system is in common automatic control state, then at first be used to refer to the signal of controller normal running by inspection, whether decision process controller 100 is normal.If this controller is unusual,, keeps opening order to output to each valve, and the operation of each valve is changed to manual operation mode then in step 308 and 312.On the other hand, if controller 100 is normal,,, carry out the following check of interlocking logic according to RTB normality diagnostic result for each measuring-signal relevant with each final control element then in step 300.

At first, the operation of check small size valve 700.By checking the measurement opening of small size valve 700, whether operate according to control command check small size valve 700 in step 302.If valve 700 operations are normal, then, whether correctly operate at step 303 check valve 700 by the limit switch signal of test valve 700, satisfy collaborative restriction.If it is limit switch signal is normal, then, whether normal at step 304 check pneumatic supply by checking the pneumatic supply switching signal.If detect the unusual of valve 700 at step 302 any place to 304, the unusual counter action that then in step 310 begins small size valve 700 final control elements, takes place, by close the control command of (or opening) large scale valve and small size valve fully to EMV output, carry out the fail safe operation.If all results for the above check of small size valve 700 are normal, then in step 305 to 307, by with the identical process of operation that is used for checking small size valve 700, the operation of check large scale valve 600.If detect any unusually to 307 in step 305, then carry out the fail safe operation of EMV similarly.Yet sometimes, only to the final element that is used for Collaborative Control carries out the fail safe operation.

The above process that is used for handling the interlocking logic is stored in the storer 203.If desired, then can monitor the state of handling the interlocking logic by the interlocking logical transition being become sequential chart or logical circuitry and on the CRT that safeguards in the docking station shown in Figure 4, showing these figure.

As mentioned above, in this embodiment, utilization is stored in a program among the PDCM, calculating is used for each control command of the common a plurality of flowrate control valves that use of same traffic control function, and, carry out Collaborative Control by a plurality of flowrate control valves according to from the control command of PDCM through the transmission of serial data signal transmission line.And each interlock function that is used for two valves is realized jointly by a logical program that is stored in PDCM.Like this, can easily form a control system, and need not be divided into each element to the final control element group that is used for realizing identical control function, its each by an independent driving circuit control.Therefore, the control performance of apparatus control system can be improved, and the fail safe design can also be easily realized.

Although explained the Collaborative Control of large scale valve and small size valve in this embodiment as an example, application of the present invention is not limited to this example.For example, in cogeneration plant,,, carry out the similar Collaborative Control of this large scale auxiliary element with its subsidiary component as make-up pump, recirculation pump, control oil pump, fuel feed pump, petroleum pump etc. for the large scale auxiliary element.The present invention can be used for a kind of like this Collaborative Control of large scale auxiliary element, and can produce the identical effect of controlling with bivalve that this embodiment produced.

Simultaneously, for a plurality of input/output points of Collaborative Control needs that comprise the protection operation, for example greater than 20, as shown in this embodiment.Yet, in PDCM according to this embodiment, owing to,, be inevitable although in classical control system, use the connector of special requirement so needn't use the connector of special requirement by adopting the serial data signal transmission method that a plurality of input/output points can be set.Like this, comprise that the design of the apparatus control system of Collaborative Control becomes easily, and can also improve the maintainability of apparatus control system.

According to the present invention, owing to be connected in the final control element driver module of process controller at each, a serial i/F who is used for controlled auxiliary element transmission data is provided, and final control element driver module is connected to a controlled auxiliary element with a serial data signal transmission line, so can realize the standardization of significantly the reducing of cable amount, final control element etc., this makes building equipment control system ratio be easier to, and has reduced the production cost of apparatus control system.

And, according to the present invention, in each final control element driver module, install under the situation of a CPU, CPU is independent of process controller and carries out control calculating, and realize each auxiliary element functions peculiar, interlock function for example, because for final control element and its subsidiary component, the layout of input/output point is not fixed in the final control element driver module, difference aspect the hardware method of attachment, so by freely rearranging input/output point, add or improve control function becoming easily, this can improve the controllability and the reliability of apparatus control system.

And, according to the present invention, under the situation of a control function of collaborative realization of passing through one group of final control element, owing to can finish control function by a final element drives module, and need not be divided into each element to final control element group, its each by an independent driving circuit control, so can improve the control performance of apparatus control system, and make the fail safe design of apparatus control system become easy.

Claims (14)

1. apparatus control system, by an a plurality of process controller and principal computers that are connected on the described network on the network that are connected to are installed in the central member pulpit, come the control procedure element, each of described process controller comprises at least one final control element driver module, and described module is connected at least one of described process component through a data transmission device;

Wherein said data transmission device be can two-way execution serial 4 data-switching the serial data signal transmitting device, it is provided at described final control element driver module place, by a serial data signal transmission line that in described serial data signal transmitting device, provides, can import a plurality of data-signals of a plurality of data-signals/therefrom export to described final control element driver module, a plurality of data-signals are included in the measured value of process variable on control command signal of a final control element of each process component and the process component.

2. apparatus control system according to claim 1, wherein said final control element driver module comprises: a nonvolatile memory that is used for storing a software, the peculiar function of the described controlled final control element of this software processes; With one be used for being independent of the CPU that described process controller is realized described software; And, handle these data of necessary data of described function/therefrom export to described final control element driver module input through described serial data signal transmission line.

3. apparatus control system according to claim 2, the peculiar described function of wherein said controlled final control element are to be used for carrying out the maintenance operation of described controlled final control element and/or the defencive function that fail safe is operated.

4. according to the described apparatus control system of one of claim 1 to 3, also comprise: a remote cabling cartridge module, be installed near the described process component, comprise and be used for carrying out bidirectional linked list/parallel data conversion and through the serial data signal transmitting device of described serial data signal transmission line data-signal; With an input/output end port, be parallel-connected on the drive unit of instrument and described process component, be used for the described data-signal of I/O.

5. apparatus control system according to claim 4, wherein provide a plurality of according to 4 remote cabling cartridge module, and described a plurality of remote cabling cartridge module comprises: analog remote cabling cartridge module is used for transmitting the simulation signal on the described process component; With digital remote terminal box module, be used for transmitting the digital data signal that comprises activation signal, activation signal is through described serial data signal transmission line.

6. apparatus control system according to claim 4, wherein said remote cabling cartridge module only comprises the hardware circuit that does not have CPU and storer.

7. apparatus control system according to claim 4, if wherein the quantity corresponding to input/output point or signal kinds provides a plurality of remote cabling cartridge modules according to claim 4, then utilize the multistation method of attachment described a plurality of described remote cabling cartridge module that is linked in sequence.

8. apparatus control system according to claim 4 wherein by a dual serial data transmission line, is connected to described controlled final control element driver module on the described remote cabling cartridge module.

9. apparatus control system, by an a plurality of process controller and principal computers that are connected on the described network on the network that are connected to are installed in the central member pulpit, come the control procedure element, each of described controller comprises at least one final control element driver module, and described module is connected at least one of described process component through a data transmission device; Described apparatus control system comprises:

A nonvolatile memory is provided in the described final control element driver module, is used for a software of the peculiar function of the described controlled final control element of stores processor;

A CPU is provided in the described final control element driver module, is used for being independent of described process controller and realizes described software; And

The serial data signal transmitting device is provided in the described final control element driver module, can carry out bidirectional linked list/parallel data conversion;

Wherein in described storer, store one group of program of carrying out Collaborative Control, a specific process variable is by one group of final control element Collaborative Control in Collaborative Control, described CPU calculates each the control command that is used for described group of described final control element according to described group of described program, and by described serial data signal transmitting device, the control command serial transmission of calculating each to described group of described final control element.

10. apparatus control system according to claim 9; wherein one group of procedure stores of protecting described group of described collaborative final control element is in described storer; described CPU is through described serial data signal transmitting device; reception is used for monitoring the data of the abnormal operation of each final control element; if and in any one described group described final control element, detected abnormal operation, then at least the final control element of a part would be controlled to the fail safe state.

11. according to claim 9 or the described apparatus control system of claim 10; wherein said process controller comprises monitoring arrangement; be used for being undertaken at least one of package of Collaborative Control and described group of described final control element of protection by observation; monitor the treatment state of CPU described in each final control element driver module; package is stored in the interior described storer of described corresponding final control element driver module; the described monitoring arrangement that is used for CPU described in each final control element driver module is connected to the described network of described central member pulpit, and by described principal computer management.

12. apparatus control system according to claim 9, wherein said group of described final control element is one group of valve and one group of pump with different flow with different openings size.

13. process controller that is used for controlling a plurality of process components, have: one is used for carrying out calculating with the CPU that controls described a plurality of described process components and a plurality of through the final control element driver module of a bus to the described CPU, each of described a plurality of described final control element driver modules is connected at least one of described process component, and described process controller comprises:

A nonvolatile memory is provided in the described final control element driver module, is used for a software of a peculiar function of controlled process element of stores processor;

One the 2nd CPU is provided in the described final control element driver module, is used for being independent of a described CPU and realizes described software; And

An I/O part is used for by using a serial data signal transmission line, necessary data of calculating and the necessary data of the distinctive calculating of described the 2nd CPU that I/O is carried out by a described CPU.

14. process controller according to claim 13, wherein the described function by described software processes is by collaborative interlocked operation and/or the Collaborative Control of carrying out of one group of final control element.

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