安全联锁系统的可靠性及可用性分析

SIS(SafetyInterlockingSystem)ESD(EmergencyShutDown)IEC()SafetyRelatedSystem()ISA-S84.01(SafetyInstrumentedSystem,SIS)SISSISIEC(SafetyIntegrityLevel,SIL)SIL4SIL1SIL2SIL3SIL4SILIECSILISAS84.01SIL4SIL4IECDINV19250(SafetyRequirementClasses)AK8AK1AK81DINIECISA3[(SHB-Z06-1999)]IECSILIEC6150842DIN19250DINVDE0801ISAS84.01IEC61508/61511TIEC61508(SafetyIntegrityLevels,SIL)PFD(ProbabilityofFailureonDemand)3(PE)(SHB-Z06-1999)(RReliability)(A:Availability)A=MTBF/(MTBF+MDT)(MTBF)(MDT)F(t)F(t)=1e-t(1)=1+2+3+(2)1R(t)R(t)=1F(t)=1(1-e-t)=e-tR0(t)R0(t)=e(1+2+3+)t=e1te2te3tR0(t)=R1(t)R2(t)R3(t)3R1(t)R2(t)R3(t)R0(t)R0(t)=1(1R1(t))(1R2(t))(1-R3(t))(4)R1(t)R2(t)R3(t)AA=MTBF/(MTBF+MDT)(5)(1)I/O(2)(3)(4)DCS1.(1)I/O(PE)1RMTBF1MDTRXRX=R(6)AX=MTBF/(MTBF+MDT)(7)(2)I/O21(PE)211(4)RF1RF1=1(1RX)2=2RXRX2(8)MTBFF1=1/2MTBFMDTF1=2MDT(5)AF1AF1=MTBFF1/(MTBFF1+MDTF1)=1/2MTBF/(1/2MTBF+2MDT)=MTBF/(MTBF+4MDT)(9)(3)I/O22(PE)2222(3)RF2RF2=RX2(10)MTBFF1=2MTBFMDTF1=1/2MDT(5)AF2AF2=MTBFF1/(MTBFF1+MDTF1)=2MTBF/(2MTBF+1/2MDT)=4MTBF/(4MTBF+MDT)(11)(4)I/O21D(PE)21222(PE)(3)RF3AF3RF3=RX2=RF2(12)AF3=4MTBF/(4MTBF+MDT)=AF2(13)(6)(8)(10)(12)RRXRF1RF2RF31RF2=RX2=RF3RXRF1RX=RF2RX=(1(1RX)2)RX=(2RX-RX2)-RX=RX-RX20RF2=RF3RXRF1(14)(7)(9)(11)(13)AF2=AF3=4MTBF/(4MTBF+MDT)MTBF/(MTBF+MDT)=AXAX=MTBF/(MTBF+MDT)MTBF/(MTBF+4MDT)=AF1AF2=AF3AXAF1(15)(14)(15)I/O2121D222.I/O33133/4(3)(4)RF4RF4=1(1R2)2=2R2R4(16)I/ORF5RF5=R2(16)RF4I/O2I/OI/OI/OI/OI/OI/O2ABA22B21(2)20001)R/(2)(MTBF)/()20035