Variable-Voltage Variable-Frequency control represents the most
successful used method in speed control of 3-phase induction motor, which is
implemented by using PWM techniques. This paper proposes modeling and
simulation of sinusoidal PWM voltage source inverter as a VVVF A.C drive. The
dynamic model, simulation of 3-phase induction motor, and open loop speed
control system is proposed too. The PI closed loop controller of rotor slip
regulation is illustrated as a traditional speed control method, which gives stable
operation behavior of motor speed in the constant torque region with settling time
=0.5 sec and maximum overshot =20%, but unstable operation in the field
weakening regions with steady state error =15%. The Artificial Neural Network
(ANN) is going to be the modern type of speed controller. This paper proposes
NARMA-L2 (Nonlinear Autoregressive-Moving Average) neural network as an
improved Artificial Neural Network technique, and trained as a close loop slip
regulation controller, which gives an ideal performance with settling and rise time
= 0.18 sec, maximum overshot and steady state error less than 1% in different
speed range and constant air gap flux, including the field weakening regions.