Induction Motors have been used as the workhorse in the industry for a long time due to its easy build, high robustness, and generally satisfactory efficiency. However, they are significantly more difficult to control than DC motors. One of the problems which might cause unsuccessful attempts for designing a proper controller would be the time varying nature of parameters and variables which might be changed while working with the motion systems. One of the best suggested solutions to solve this problem would be the use of Sliding Mode Control (SMC). This paper presents the design of a new controller for a vector control induction motor drive that employs an outer loop speed controller using SMC. Several tests were performed to evaluate the performance of the new controller method, and two other sliding mode controller techniques. From the comparative simulation results, one can conclude that the new controller law provides high performance dynamic characteristics and is robust with regard to plant parameter variations.
- Induction Motor
- Sliding Mode Control
- DC Motors
- PI Controller
Fig. 1 Induction motor drive system with sliding mode controller
EXPECTED SIMULATION RESULTS:
Fig.2 (a)Rotor speed tracking performance (b)Rotor speed tracking error (c)Control effort
Fig.3 (a)Rotor speed tracking performance (b)Rotor speed tracking error (c)Control effort
Fig.4 (a)Rotor speed tracking performance (b)Rotor speed tracking error (c)Control effort
In this paper, new technique to reduced chattering for sliding mode control is submitted to design the rotor speed control of induction motor. To validate the performances of the new proposed control law, we provided a series of simulations and a comparative study between the performances of the new proposed sliding mode controller strategy and those of the Pseudo and Saturation sliding mode controller techniques. The sliding mode controller algorithms are capable of high precision rotor speed tracking. From the comparative simulation results, one can conclude that the three sliding mode controller techniques demonstrate nearly the same dynamic behavior under nominal condition. Also, from the simulation results, it can be seen obviously that the control performance of the new sliding mode controller strategy in the rotor speed tracking, robustness to parameter variations is superior to that of the other sliding mode controller techniques.
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