Title :
Improvement of a stator-flux-oriented speed-sensorless control of an induction motor
Author :
Gastli, Adel ; Tomita, Masaaki ; Takeshita, Takaharu ; Matsui, Nobuyuki
Author_Institution :
Nagoya Inst. of Technol., Japan
Abstract :
Simulations have predicted high performance control characteristics in the torque and speed sensorless control algorithm which uses a stator-flux-controlled V/f PWM inverter. However, in the actual control system, different problems occurred. Among these problems, there are the fluctuation of the inverter input voltage and the voltage error due to switching time lag of power transistors and to voltage drop in inverter power devices. These voltage errors are a big effect on the flux estimation and cause oscillations of the torque and even instability of the drive system especially at low speeds. This paper investigates these problems and proposes solutions to improve the accuracy of the control system. A very simple implementation of these solutions has shown considerable improvement of dynamic as well as steady-state control characteristics.<>
Keywords :
control system synthesis; induction motors; invertors; machine control; machine theory; power transistors; pulse width modulation; stators; switching circuits; torque control; velocity control; PWM inverter; accuracy; algorithm; control system synthesis; induction motor; input voltage; instability; machine control; machine theory; oscillations; performance; power transistors; sensorless; switching time lag; torque control; velocity control; voltage drop; voltage error; Control systems; Fluctuations; Power transistors; Predictive models; Pulse width modulation inverters; Sensorless control; Stators; Steady-state; Torque control; Voltage;
Conference_Titel :
Power Conversion Conference, 1993. Yokohama 1993., Conference Record of the
Conference_Location :
Yokohama, Japan
Print_ISBN :
0-7803-0471-3
DOI :
10.1109/PCCON.1993.264148
