Author : H. R. Tayebi
Publisher :
ISBN 13 :
Total Pages : 217 pages
Book Rating : 4.:/5 (117 download)
Book Synopsis High Performance Current Regulation for Unity Power Factor Current Source Inverter-fed Induction Motor Drives by : H. R. Tayebi
Download or read book High Performance Current Regulation for Unity Power Factor Current Source Inverter-fed Induction Motor Drives written by H. R. Tayebi and published by . This book was released on 1997 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this research work optimal control of a CSI induction machine drive for highperformance current regulation and unity power factor is studied. A model-basedoptimal predictive control scheme, generalized predictive control (GPC), is developedfor high performance DC link current regulation in a vector controlled CSI-fed inductionmachine drive. The algorithm models the drive circuits using a simple RL structure. Theparameters of the model are estimated on-line to track system variation using a RecursiveLeast Square estimator. This model is used to predict the DC link current output over acertain length of time ahead and the best voltage control signal is generated throughminimising a quadratic cost function. The controller is also adaptive to motor parametersvariation and speed command changes and load disturbances. The performance of thecontroller in improving the dynamic response of a phase controlled CSI drive, has beencompared with that of a PI controller and found to be superior.An experimental rig was developed for testing the control algorithm which comprises apower unit and a control unit. The power unit consists of a full-wave controlled rectifier,DC link filter, inverter and induction motor. The control unit consists of a 486DX4-100personal computer which was connected to the power unit through an interface board.Programming of the system was done with the C and assembly languages. It was verifiedexperimentally that GPC control gives faster and smoother performance to the system. Using GPC as the DC link current controller, an IGBT based rectifier was developed for a high performance CSI drive with unity power factor and sinusoidal supply current. Space vector modulation (SVM) technique is proposed as an efficient modulation strategy for pulse width modulation of the rectifier switches. Compared with the traditional triangulation technique, space vector PWM waveforms are shown to have a better performance with respect to the ease of generation and efficiency and are suitable for real-time applications. Furthermore the SVM control can ensure zero degree phase displacement between input voltage and current. This is obtained by using a three-phase input LC filter and adjusting the phase angle of the input reference voltage corresponding to the input current variations. The input filter also eliminates the high order harmonics due to high frequency switching of IGBTS.