Accurate adaptive integration algorithms for induction machine drive over a wide speed range

This paper presents three new architectures for designing accurate adaptive integration algorithms (AAIA) for quasi exact flux position and magnitude estimation of induction machines over a wide speed range. Pure integrators are in practice affected by DC-offset and DC-drift problems while estimating flux position and magnitude from the back electromotive force (emf). Modified integration algorithms based on low pass filter (LPF) or programmable LPF are also known to be affected by the cut-off frequency. The proposed architectures are based on the association of high pass filters (HPF) and pure integrators. DC-offsets and drift problems are eliminated by the HPFs before integration. The HPF characteristics are used for magnitude (gain) and position (angle) compensation. The HPF cut-off frequency can be chosen far from the inverse of stator time constant without affecting the estimation of low frequency signals resulting into good accuracy over a wide speed range. A strong agreement is observed between the simulation and experimental results that demonstrate the accuracy of the proposed architectures. The proposed AAIA can be used for any kind of induction machine (IM) since they are independent from the IM parameters. The AAIA can also be used to estimate stator flux in order to estimate the IM parameters online, as required for adaptive control in indirect rotor flux oriented control (IRFOC) schemes

[1]  R.D. Lorenz,et al.  Stator and rotor flux based deadbeat direct torque control of induction machines , 2001, Conference Record of the 2001 IEEE Industry Applications Conference. 36th IAS Annual Meeting (Cat. No.01CH37248).

[2]  Dong-Seok Hyun,et al.  An improved stator flux estimation for speed sensorless stator flux orientation control of induction motors , 1998, PESC 98 Record. 29th Annual IEEE Power Electronics Specialists Conference (Cat. No.98CH36196).

[3]  Joachim Holtz,et al.  Drift and parameter compensated flux estimator for persistent zero stator frequency operation of sensorless controlled induction motors , 2002 .

[4]  P. Sicard,et al.  Real time flux and torque estimator for induction machines , 2004, Canadian Conference on Electrical and Computer Engineering 2004 (IEEE Cat. No.04CH37513).

[5]  Kaushik Rajashekara,et al.  Comparative analysis of torque-controlled IM drives with applications in electric and hybrid vehicles , 2001 .

[6]  Bin Wu,et al.  New integration algorithms for estimating motor flux over a wide speed range , 1997 .

[7]  Thomas G. Habetler,et al.  Stator resistance tuning in a stator-flux field-oriented drive using an instantaneous hybrid flux estimator , 1998 .

[8]  C. P. Bottura,et al.  A flux observer for induction machines based on a time-variant discrete model , 1993 .

[9]  Jennifer Stephan,et al.  Real-time estimation of the parameters and fluxes of induction motors , 1992, Conference Record of the 1992 IEEE Industry Applications Society Annual Meeting.