Brushless Direct Current motors are one of the motor types rapidly gaining popularity. The major problem in BLDC drive system is that some disturbances are originated in the drive which will results in errors and reduces the stability of the system. Conventional controller is used to control the speed of the motor, but the response of the system is affected by steady state error and represents a poor transient response. To regulate the speed of the motor at desired speed is an important application in automotive industries. So we use a Linear Quadratic Regulator controller and Linear Quadratic Gaussian to regulate the speed of the motor. The state variables and control variables of the BLDC drive system are synthesized in this paper. The main objective of this paper is to formulate the control law which results in minimum performance index. This paper spotlights both the design and simulation of optimal & Robust control systems for BLDC motor drive system.

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Brushless Dc (bldc) Motor Drives Linear Quadratic Regulator (lqr) state Variables Performance Index Control Variables