Integrated solution for induction motor control

44 Fo Induc ion Mo o Con ol , The command speed has an'S' o m, ypical in e ical ope a ion sys ems. The eason I o his command speed is ha a so accele a ion/decele a ion a oids ab up mo emen s in he ele a o cabin, inc easing he com o le el. J.L. Mo a, F. Ba e o, E. Gal an, F. Colod o, J.N. Tombs, M. Ba anco*, A. To alba and L.G. F anquelo; Dp o. de Ingenie a Elec onica, Escuela Supe io de Ingenie os, Se illa Spain Ajuzzy-logic based con olle jo he speed and posi ion con ol I is well known ha high pe o mance speed egula ion o an induc ion machine equi es ec o con ol. By means o a coo dina e ans o ma ion o measu ed cu en s, we can ob ain wo new cu en componen s di ec ly ela ed wi h he lux and o que o he machine, so we can con ol he induc ion mo o as a sep- a a ely exci ed DC machine. The angle ha de ines his coo dina e ans o ma ion mus be es ima ed using he dynamic modelling o he Olud I '1' machine which equi es a p ope knowledge o he o o ime cons an . The ope a ions ha mus be pe o med o a ec o con ol algo i hm a e nowadays imple- men ed in a mic op ocesso , usually a DSP. This '0' J Vec o L Con ol ! S ...... i .che p og ammable bi s and s a e o hem PCIM Eu ope May 2002 In eg a ed Solu ion o Induc ion Mo o Con ol The ope a ions ha mus be pe o med o a ec o con ol algo hm a e nowadays implemen ed in a mic op ocesso , usually a DSP solu ion is expensi e in de elopmen cos , so a wi h a highly accu a e speed and o que con- speci ic chip ha could pe o m all he unc ions ol, especially in low speed ope a ion ange. equi ed can be an in e es ing solu ion. This a icle p esen s an ASIC, named ASITRON ha in eg a es all he logic equi ed o high pe o mance con ol o induc ion mo o s. The ASIC is pa o a compac indus- ial con ol sys em o ele a o s build by Macpua sa Company ( igu e 1). In ele a o indus y, mo o s a e used in a pa icula way: he mo o is ope a ed om ze o speed o nom- inal posi i e o nega i e speed and hen pu back o ze o, while posi i e o nega i e o que loads a e applied. This unc ional ope a ion is accomplished due o ASITROI'J. AS mON, igu e 2, in eg a es he indi ec ec- o con ol algo i hm, a digi al achome e , a 64- ules buil -in uzzy logic based con olle o speed and posi ion egula ion, ~ PWM based cu en con olle and a se o ex &naJ in e aces, such as AID con e e s o cu en measu e- men s and a mic op ocesso pa allel in e ace. Figu e 3 depic s a block diag am o he ASIC, including i s p og ammabili y. No ice ha i can pe o m a 3-phase PWM cu en o o~age gen- speed and posi ion egula ion. The com o eeling o passenge s is ela ed e a o , a classical ol age- equency con olle The indi ec ec o con ol algo i hm, he coo dina e change and he cu en con ol loop ha e been implemen ed using a 13-bi s mul i- plie and an 18-bi s adde . Th ee inpu s, he command o que cu en (ob ained om he uzzy con olle ), he lux cu en e e ence and he mechanical speed (ob ained om a speed measu emen block) a e used o de e mine he elec ical angle, needed o coo dina e ans o - ma ion, and o ob ain he e e ence cu en s, necessa y o he inne cu en con ol loop, ig- u e 4. ~ ... .J ... J --- ... --- ----- ... _- ,. ... ;- Ton FREO T+!· , .. , o o implemen a modem ec- o ial con ol o he induc ion mo o wi h a uzzy-logic based MUX NPUT, R.IlM (32x4x12) bas I---c--'-T----oo-i Mo eo e , he cu en con ol loop is based CT1 SOT, CT2 de5i ed ou pu ------'--+I DE FUZZIFIER I I I CT1 CT2 1 I 1 I 1 1 1 1- ___________ -0- _______ ~_G.!.,_ -------- __ ...! In eg a ed Solu ion Fo Induc ion Mo o Con ol con inues on a 10-bi s esolu ion PWM modula ion, whe e he iangula ca ie equency can be se om 5kHz o 43kHz. A p og ammable PI con olle closes he loop. The chip p oduces 6 digi al pulses o d i e he ga es o a h ee-phase in e e wi h p og ammable dead imes (up o 6ms) and na ow pulse dele ion (up o 3ms). The wo ain pulses o an op ical encode a e used o de e mine speed wi h 16 bi s esolu ion. A mul i ange CET me hod is implemen ed o co e a wide speed ange (0 o ±82 Hz) wi h a limi ed absolu e e o depending on he num- be o pulses pe e olu ion o he encode . ASITRON implemen s a uzzy-logic based con olle o he speed and posi ion con ol o an induc ion mo o , igu e 5. This con olle has h ee inpu s ( he speed e o , he in eg al speed e o and ano he one ex e nally p og ammed) and one ou pu ( he command o que cu en ). The d e en ules (up o 63) ha de ine he con- ol su ace a e s o ed in a buil -ill RAM. Using his con olle , an imp o emen in speed con ol can be ob ained when compa ed wi h a classi- cal PI egula o . 46 Figu e 6 shows an induc ion mo o con olled using ASITRON om low speed o nominal 0 .0 5 0.1 0.15 0.2 0.25 0 .3 1"", pO ( S) Co H e n es la .10 speed and, hen, pu back o low speed wi h- ou load o que. Mechanical speed and mo o cu en s ha e been depic ed. No ice ha he command speed has an'S' o m, ypical in e ical ope a ion sys ems. The eason o his command speed is ha a so accele a- ion/decele a ion a oids ab up mo emen s in he ele a o cabin, inc easing he com o le el. The mo o esponse, applying a a ed speed s ep is shown in igu e 7. I}inally, igu e 8 p es- en s he sys em esponse when a a ed o que s ep is applied a a mechanical speed o 25Hz. The esul s ha e been ob ained using a 10kW ac-mo o es - ig con olled wi h ASITRON ha has been p og ammed o pe o m bo h, an indi ec ec o and a uzzy logic based 24.4 24 .2 0.35 0.4 0.45 24 0 0.2 40 speed egula ion. In his a icle, a highly p og ammable ASIC o con ol 3-phase ac-machines has been p e- sen ed. ASITRON can be con igu ed o pe o m 3-phase PWM cu en ( ol age) gene a o , a classical ol age-' equency con olle o o implemen a mode n ec o ial con ol o he induc ion mo o wi h a uzzy-logic based speed and posi ion egula ion. The chip has been ab- ica ed using a 0.7 mm CMOS digi al echnol- ogy and i is p esen ly he co e o a ligh-pe - o mance AC-d i e o ele a o s manu ac u ed by he Macpua sa Company. Many uni s a e wo king oday showing excellen esul s. • en e pcim 10664 a www . pcim-in o.com PCIM Eu ope May 2002