Development of Integrated Alstom Gasification Simulator for Implementation Using DCS CS3000

Transcription

1 Proceedngs of the 7th World Congress The Internatonal Federaton of Autoatc Control Seoul Korea July Developent of Integrated Alsto asfcaton Sulator for Ipleentaton Usng DCS CS000 A. Haryanto* P. Sregar** D. Kurnad** and Keu-Shk Hong* * School of Mechancal Engneerng Pusan Natonal Unversty; #0 Jangjeon-dong ujeong-gu Busan Korea;(e-als: {a.haryanto kshong}@pusan.ac.kr). ** Departent of Engneerng Physcs Bandung Insttute of Technology; #0 anesha Bandung 0 Indonesa;(e-als: {psregar Abstract: In ths paper we explore the developent of ntegrated plant sulator that ntegrates MATLAB as an engne and DCS CS000 as an ndustral controller. It works realte and onlne lke real ndustral control plant schee. For ndustral practcans lke operator and engneer ths sulator s very useful as an operator tranng or control educatonal tools and can be used to pleent loop parng selecton and tune the controller paraeters. As a requreent of controllng usng DCS ths paper provdes ntegrated analyss tools for loop parng by pleentaton relatve gan array (RA) ethod and decentralzed relatve gan (DR). Plant case for ths sulator s Alsto gasfcaton. Keywords : DCS CS000 ntegrated sulator Alsto gasfcaton parng selecton.. INTRODUCTION In lne wth the coplexty of ndustres control probles also becoe ore and ore coplex. It akes a challenge for unversty especally n control area to solve and consder t and to ntegrate ndustral aspects nto teachng actvty. The an proble n provdng practcal control nfrastructure for teachng actvty s how expensve t s. It s related to provdng control nstruents and antenance cost. Another needs n provdng that nfrastructure s the requreent of enough space that relatvely dffcult for several unverstes to provde t. For solvng that proble one way that can be taken s developent of ndustral sulator that represents real ndustry. Recently we can take advantages fro rapd developent of coputer and councaton protocol technology to develop plant sulator n coputer. It s called as ntegrated plant sulator because ths sulator ntegrates engne data transfer councaton va object-lnked-ebedded process control (OPC) technology and dstrbuted control syste (DCS) as a real ndustral controller. Frstly the sulator engne s developed n MATLAB and then data s transferred va open syste connectvty OLE for Process Control (OPC) technology and controlled by DCS CS000. For several decade any developers have tred to buld plant sulator usng DCS they are (Wanye et al. 00; eddes et al. 998; and Nan Ye et al. 000). They developed sulator nherently n DCS software but n ths research we develop sulator separately n MATLAB n order to obtan ts proved nuercal sulaton so gves ore accurate calculaton and easy to pleent the control algorth. The contrbutons of ths paper are: an ntegrated sulator consstng of a real controller a real councaton server but a plant prograed n MATLAB s proposed. The second ntegrated sulator also provdes nputs-outputs parng tools that enable control engneers to choose and sulate the best parng of control loop based on RA and senstvty analyss of DR. Ths parng tool desgned flexble and easy to be reconfgurable for any plant case. The resulted loop parng wll be very useful for pleentaton of ult-loop controller n DCS.. SIMULATOR CONFIURATION The proposed ntegrated sulator s depcted n Fg.. It conssts of three parts: an engne that provdes the dynacs of the plant a councaton server that connects between the engne and control syste and a control syste that perfors dstrbuted control. It s a hardware-n-the-loop sulaton (HLS) ncludng the real controller and councaton server as the plant s odelled n software. In ths paper as an engne for solvng the dynacs of the Alsto gasfcaton plant the MATLAB/Sulnk s selected for ts easness of prograng and graphcal tools. As a councaton server an NI OPC s used. As a dstrbuted control syste Yokogawa DCS CS000 Japan s used for ontorng and operaton purposes.. Control Syste: DCS CS000 The DCS CS 000 of Yokogawa Japan s an ntegrated producton control syste whch s used to anage and control the operaton of plants n a wde varety of ndustres ncludng petroleu refneres petrochecal checal /08/$ IFAC / KR-00.08

2 Seoul Korea July pharaceutcal food and beverages paper and pulp steel and non-ferrous etals ceent power plant gas water and wastewater and others (Yokogawa 007). The DCS anly conssts of three parts: feld control staton (FCS) huan nterface staton (HIS) and V-Net data councaton. The archtecture of the DCS CS000 adopted n ths paper s depcted n Fg.. The syste has a wndow based nterface and a drag and drop functon and oreover provdes an operaton nterface to other systes ncludng producton anageent systes qualty control systes etc. Fg. Data transfer between Engne and DCS Fg. Scheatc of the proposed ntegrated sulaton. Fg. The archtecture of DCS CS000 Fg. The OPC frae-work on DCS CS000.. Councaton: NI OPC Server In order to access data fro or to DCS CS000 there are soe ssues to be consdered see Fg.. In the OPC fraework an applcaton requestng data s referred to as an OPC clent and an applcaton provdng data s referred to as an OPC server. Through the use of an NI OPC nterface t becoes possble to use an OPC server operatng on an HIS to access varous knds of data on FCS statons and the HIS tself fro OPC-copatble clent applcatons operatng on Wndows achnes. Moreover t s possble to notfy alars whch occurred n FCS and events. The type of OPC used n ths paper s an OPC-data-access that has functon to read and wrte plant data. Data produced by engne and wrtten to DCS are y y y and y as process varables (PVs). Data read fro DCS are u u u and u as anpulated varables (MVs). DCS conducts control algorth based on PV data and setponts (SVs) data. The explanaton of data transfer schee can be seen n Fg.. Fg. 5 Process flow dagra of the Alsto plant. Plant Model In ths paper we use the Alsto gasfcaton odel as our plant that was obtaned by (Moreea-Tahhaa 00; Rudy- 085

3 Seoul Korea July Zhang 006; and R. Dxon 006). Fg. 5 shows the process flow dagra of the Alsto plant. It s a ult-varable plant that conssts of fve control nputs (flow coal rrgate flow ass flow ass lestone flow stea and flow extracton char) four control outputs (gas value calorfc bed ass fuel gas pressure and fuel gas teperature) and one dsturbance (snk pressure noted by P SNK n Fg. 5). The transfer functon odel of the Alsto plant are gven by y y s ( ) y s ( ) y d d d d P snk u u s ( ) + u u P snk s pressure dsturbance (P SNK n Fg. 5) j (s) and d (s) can bee seen n appendx A. Steady state and dsturbance gan of the Alsto plant are gven as follows.0565e e (0).66e d.50e 6.60e.688e e5.70e 5.055e e e [ e ] T ( 0) 5. These gans wll be used n control structure selecton and analyss.. CONTROL STRUCTURE SELECTION In a DCS approach the control structure has to be chosen n the way that the nteracton aong control loops s nzed. In the decentralzed control approach the loop confguraton s the ost portant thng n order to acheve the best control perforance of the plant. Ths eans that the decson on what nput s to be anly used to control a certan output s ore portant than the selecton of a control ethod or the desgn of control gans of the chosen control algorth. If the control structure s properly chosen tunng of selected controllers wll never reach a desred perforance. In sae case stakenly chosen control outputs and nputs wll result n a lted perforance whch ths atter cannot be overcoe by any tunng ethod and also any advanced controllers lke MPC (Chen and McAvoy 00).. Loop Parng Usng the RA Method In ths paper we wll try to pleent the relatve gan array (RA) ethod and then evaluate ts perforance by usng the decentralzed relatve gan (DR) copared to the currently pleented loop. The RA equaton forulated by Brstol (966) s CV MV j λ j CV MV j MV k Constant CV k Constant λ j s the RA value CV s the change of the -th controlled varable MV j s the change of the j-th anpulated varable. The loop parng s selected n the way that the RA value s close to one. Based on ths approach the loop parng for the Alsto plant s proposed as follows: y u (Fuel as Calorfc Value Coal Flow) y (Bed Mass Char Extracton Flow) u y (Fuel as Pressure Ar Mass Flow) u y u (Fuel as Teperature Stea Mass Flow). Whch s dfferent fro the currently pleented loop parng n the plant (Dxon 00) as y u (Fuel Calorfc Value Ar Mass Flow) y (Bed Mass Coal Flow) u y (Fuel as Pressure Stea Mass Flow) u y u (Fuel as Tep. Char Extracton Flow). It s coented that the RA approach s based on the assupton that the plant s controlled perfectly. Ths analyss s only based one steady state gan of the plant atrx.. Analyss of RA Results Usng DR Propertes The RA analyss has been proved for several plant cases actually for x plant atrx (Brstol 966; Cu & Jacobsen 00). In ths paper we wll copare the obtaned loop parng based on RA and the currently pleented loop by usng decentralzed relatve gan analyss (Schdt & Jacobsen 00). The DR analyss reles on the proble of lted control bandwdth. In ths approach we do not need to defne the controller type copletely but only by defnng a easure of the acheved perforance that s free fro any partcular controller t s called ndependent desgn. The crtcal frequency of the plant s the regon around control bandwdth (ω c ) to acheve the desred perforance. Ths ω c then can be elaborated by soe key specfcatons based on the frequency response lke phase argn (Ф ) gan cross over and roll-off rate (n ro ). In control theory ths key specfcaton then can be pleented by usng the loop shapng theore. () 085

4 Seoul Korea July Usng the nternal odel control (IMC) and the lead-lag copensator forulaton loop shapng theore than defned by partcular key specfer (f ) whch actually contans nforaton about bandwdth frequency and cross over frequency of the plant. The forulaton of f (s) s f () + l f (s) s the perforance specfer l (s) represents the desred open loop transfer functon whch s defned as follows: When the roll-off rate n ro - (based on a leadcopensator schee) k ( s + bn ) l () s N ( s + b) ω c b () N k ω N (5) c π N ( φ ) tan. (6) N When n ro roll-off rate - (based on IMC schee) k c l ω (7) s + t t c π tan( φ ) (8) ω k + jt ωc (9) and t and k are te and gan ntegrator respectvely. The DR analyss has two nteracton easures. They are the senstvty nteracton easure (X) and the dsturbance senstvty nteracton easure (X d ) whch are defned as follows: [ ~ ~ I + (( F I ) + ) ] X A (0) [ I ~ F I A ~ + (( ) + ) ] d X d () s an off-dagonal atrx ~ s resulted fro the separaton of the syste ~ nto a dagonal all pass transfer atrx A ~ ~ and a dagonal nu phase syste ( s ). So ~ ~ ~ that A ~ s dag () and d s dsturbance gan. The RA result when evaluated by DR approach shows that the loop parng fro (Dxon 000) s better than the RA parng. At certan bandwdth frequency the RA parng s ore senstve to other loops and also ore senstve to the presence of dsturbances (see Fg. 5 and Fg. 6). Fg. 6 Senstvty Interacton Measure -xxx- y - u (RA); -ooo- y - u Fg. 7 Dsturbance Senstvty Interacton Measure Left : -xxx- y - u (RA); -ooo- y - u (R. Dxon) Rght : -xxx- y - u (RA); -ooo- y - u (R. Dxon). SIMULATION RESULTS Control perforance s evaluated by set pont trackng and dsturbance rejecton test for RA parngs and the currently pleented parng when controlled usng DCS. Control of the Alsto gasfcaton plant usng DCS ndcates that the currently pleented loop control gves better n perforance responses (trackng the setpont and attenuatng the dsturbance) then RA whch the axu absolute error (MAE) 5069 for y 8.55 for y s 578 for y and 0.66 for y. RA parng s 5855 for y 8.55 for y 77 for y and 0. for y. Soe sulaton results can be found n Appendx B Fg. 8 the noses appearng are fro real data transfer councaton usng -0 A and ADDA converson. 5. CONCLUSIONS Integrated plant sulator s very helpful n conductng plant operaton tranng for engneer and operator such as odfyng control loop confguraton and tunng the controller paraeters. Studes n ths paper also ndcate that usng RA analyss s not effectve n control structure selecton for Alsto gasfcaton plant. 085

5 Seoul Korea July ACKNOWLEDMENT Ths work was supported by the Regonal Research Unverst es Progra (Research Center for Logstcs Inforaton Tech nology LIT) granted by the Mnstry of Educaton & Huan Resources Developent Korea. REFERENCES Brstol E.H. (966). On a new easure of nteractons for ultvarable process control. IEEE Transactons on Autoaton Control vol. no. pp. -. Chen R. and McAvoy T.J. (00). Plantwde Control syste desgn: Methodology and applcaton to a vnyl acetate process. Ind. Eng. Che. Res. vol. pp Cu H. and Jacobsen E.W. (00). Perforance ltatons n decentralzed control. Journal of Process Control vol. () page Dxon R. Pke A. and Donne M. (000). The ALSTOM benchark challenge on gasfer control. Proc. Inst. Mech. Eng. I J. Syst. Control Eng.. pp eddes D.J Bale A.P.H. Cregan M. and Swdernbank E. (998) A Realte Sulaton of A 00 MW Theral Power Plant for Optsng Cobuston Engne. UKACC Internatonal Conference on Control. Hennng Schdt and Ellng W. Jacobsen 00. Selectng control confguratons for perforance wth ndependent desgn. Journal of Coputers and Checal Engneerng 7 pp Moreea- R.Tahha (00). Modelng and sulaton for coal gasfer n fludsed bed Journal of Fuel no. 8 pp Nan Ye Sara Vallur Mtch Barker Po-Yang Yu (000). Integraton of advanced process control and full scale dynac sulaton. ISA Transactons 9 pp Rudy A. and Je Zang (006). Control Structure Selecton for The Alsto asfer Benchark Process Usng RD Analyss. Paper n Aercan Control Conference (ACC). Techncal Inforaton (007). CENTUM CS 000 ntegrated producton control syste overvew. Yokogawa Electrc Corp. Japan. Wanye Y. Han Pu Yang Mngyu and Zhaou Lhu (00). The pleentaton of power plant sulator based on dstrbuted control syste Proc. IEEE Tencon. Appendx A. Transfer functon atrx of Alsto plant y y y y d d Psnk d d 88.5s s s e 7.08 s s s +.08e s 0.00 s s e s e 6 s s +.6 e s +.95 s s + 6.6e s s s.09 e 8 s s s s e 5 s s e 7 50 s 6.8 s s +.06 e s s s +.76 e 7 09 s.68 s s s +.8 e 5 s s 9.75 e s.09 s s + 8.e s 0.00 s s e s s s + 9.e s.67e 5 s s e s.5 e 6 d s s e 6s.0e 9 d s e 5s.9 e s d s + 0.s e 7s e d. s s e 7 u u u u

6 Seoul Korea July Apendx B Sulaton Results (a). Dxon parng (a) Dxon parng (b). RA parng Fg. 8 Fuel calorfc value response (b) RA parng Fg. 0 Teperature response (a). Dxon parng (a) Dxon parng (b. RA parng Fg. 9 Pressure response (b) RA parng Fg. Teperature response to step pressure dsturbance 0856