Abstract:
Induction motor is the most widely used electric motor in industry, EVs and HEVs
due to high reliability, ruggedness, low cost of maintenance, high torque during
starting and wide range of operating speed. However, highly non-linear dynamics
of induction motor make it difficult to control as compare to other motors. With
the development of field oriented control, the induction motor can be controlled
like separately excited dc motor. Field oriented control requires the exact information of rotor flux. Since the rotor flux is not easy to estimate due to the large
variations in the parameters of induction motor due to the surrounding and operating temperature. Rotor resistance and rotor inductance are crucial parameters
for estimation of flux. The objective of simultaneous estimation of fluxes along
with critical parameter is achieved through adaptive high gain observer. The observer estimate the actual values of rotor resistance and rotor inductance under
persistence excitation condition which guarantees the exact estimation of rotor
flux.
