EE8412 Advanced AC Drive Systems. Topic 6 Field Oriented control (FOC)

Transcription

1 Advanced AC Dive Syte Topic 6 Field Oiented contol (FOC) Souce: ABB 1 Advanced AC Dive Syte Field Oiented Contol (FOC) ectue Topi Geneal Block Diaga of FOC Diect Field Oiented Contol Diect FOC with Cuent Contolled VSI Indiect Field Oiented Contol 2 1

2 Clification of Roto flux oientation Stato flux oientation Ai-gap flux oientation Focu on oto flux oientation It i elatively iple and widely ued 3 Toque Poduction in DC Moto T e = K λ i a f a (1) T e electoagnetic toque K a - aatue contant λ f - flux poduced by field cicuit i a - aatue cuent λ f = cont T e i popotional to i a Flux λ f and i a can be contolled independently high dynaic pefoance. 4 2

3 Roto Flux Oientation Roto flux oientation i achieved by aligning the d-axi of the ynchonou efeence fae with the oto flux vecto λ i λ = and = 0 (2) d λ λ q λ θ l θ 5 Electoagnetic Toque 3P ( iqλd idλq ) 2 3P Te = ( iqid idiq ) 2 3P ( iqλd idλq ) 2 (3) (2) (3): Te = KT λ d iq = KT λ iq (4) With oto field oientation, the toque expeion in (4) fo the induction oto i iila to that of a dc oto in (1). Keep flux λ contant, T e i popotional to 6 3

4 Flux and Toque Poducing Coponent i λ θ l θ flux-poducing coponent kept at the ated value toque-poducing coponent contolled independently 7 Roto Flux Angle i λ θ l θ - oto flux angle θ - oto angle θ l - lip angle θ = θ + θ f l 8 4

5 Geneal Block Diaga of FOC λ T e λ Te i, i, i v, v, v Roto flux and toque ae contolled independently to achieve high dynaic pefoance 9 Diect and Indiect FOC Diect FOC Roto flux angle i obtained by uing flux-ening device ebedded inide the oto o uing eued oto teinal voltage and cuent Indiect FOC Roto flux angle i obtained fo detected oto poition angle θ and calculated lip angle θ l = θ + θ l 10 5

6 Syte Block Diaga Diect FOC λ T e v d v q v, v v i, i, i λ v, v, v Diect FOC - Roto flux angle i obtained by eued oto teinal voltage and cuent 11 Roto Flux Calculato i R Diect FOC l l jω λ R i v pλ i pλ λ = dt ( v R i ) λ = i + i σ = 1 2 λ i λ = + i = ( λ σ i ) 12 6

7 Roto Flux Calculato λd = λq = ( λ σ i ) d ( λ σ i ) q 2 2 λ = λd + λq λ 1 q θ f = tan λd Diect FOC Decopoing the oto flux into the d- and q-axi coponent d q Featue Only ue tato-ide vaiable to Calculato oto flux. fo which the agnitude and angle of the oto flux ae 13 Roto Flux Calculato Diect FOC i λ λ q λ d Space vecto diaga fo oto flux calculation d- and q-axi cuent and flux ae ac vaiable 14 7

8 Diect FOC Siulation Block Diaga fo Roto Flux Calculation v v v v d v q λ d λ q λ d λq x y y tan 1 x 2 x + y 2 λ i R i i R σ σ 15 Diect FOC with Cuent-Contolled VSI Syte Block Diaga λ T e i, i i i, i, i T e λ i, i, i v, v, v 16 8

9 ad Diect FOC with Cuent-Contolled VSI Cuent-Contolled VSI S 1 P S3 S5 A i V d C d v AN B C i i S4 S6 S 2 x H N i δ i δ i i i i v AN V d t1 t 2 t 3 17 Diect FOC with Cuent-Contolled VSI Siulation Reult (p) ω( T (N ) e (A) i λ (Wb), θ )f λ 18 9

10 λ T e Syte Block Diaga 1/ 1/ K T iq Indiect FOC Synchonou Fae (dc ignal) v d v q Cuent Contolle dq/abc abc/dq Stationay Fae (ac ignal) PWM VSI i, i, i M λ τ Integato θ f ω l ω = ( ω + ωl )dt 19 Indiect FOC Slip Fequency Calculation ω l = i τ λ q Refe to Chapte 14 fo detailed deivation 20 10

11 Advanced AC Dive Syte Topic 6 Field Oiented Contol (FOC) 21 11