| 摘要 |
PURPOSE:To detect the flux accurately even in the extremely low frequency region of 2-3Hz and below and to perform vector control with high accuracy, by performing an operation of the flux in the soft processing of a microcomputer. CONSTITUTION:A microcomputer 18 inputs a motor primary voltage integration value integral V1dt, a primary current integration value integral I1dt and a power factor angle integration value integral phi1dt of a periodic interval Tf of a flux phase command thetaphias digital amounts and an operation of the flux phi is performed by applying an equivalent circuit of an induction motor 3. In a vector operation circuit 4 a vector operation is performed so that the output omegar of a speed detector 8 may follow the speed command 7, outputting the primary current size I1, a phase theta and the primary angle frequency command omega1. In a current command generation circuit 5, instant phase current commands iu and iv are outputted. In a current control circuit 6 a PWM signal is generated to output into an inverter 2 so that the actual phase current may follow to current commands iu and iv. |
