| Abstract |
The paper deals with a hierarchical control approach for switched reluctance motor
control. The paper describes the features and the control problems that, arises in case of
switched reluctance motors (SRMs). In order to assure servo-quality performances SRM
requires instantaneous torque control. It means that the current waveforms must be profiled as
the rotor rotates, to obtain the imposed torque with low ripples. At low and medium speed the
SRM is controlled by the current, at high speed there is generally insufficient voltage available
to control the current, thus the motor is controlled via the firing angle.
The changeover from current control to firing angle control is occurring in function on the
operating conditions. The proposed hierarchical control is supervised by fuzzy rules,
established by a human operator function on the motor speed range and speed error.
The proposed control structure is tested in case of a four phase PWM (pulse-width modulation)
inverter fed switched reluctance motor. The implemented control system is a distributed one,
with two processors, one of them is a PlC 16C84 microcontroller and the other is a PC based
system. The control algorithm has been implemented in Lab VIEW graphical programming
environment.
The obtained experimental results show the advantages of the fuzzy based hierarchical control
against the classical control. |
