Real Time DSP Based PID and State Feedba Control of a Brushed DC Motor Ersin Yolacan, Serkan Aydin and H.Metin Ertunc Mechatronics Engineering Department Kocaeli University Kocaeli, Turkey hmertunc@kocaeli.edu.tr Abstract—In this paper, real time position, trajectory and speed controls are implemented for a serial excited brushed DC motor using PID and state feedback control methods. The purpose of this study is to keep the position and speed on desired references. The control blocks are designed on Matlab-Simulink and applied by F28335 DSP control board. The experimental results of PID and state feedback methods are compared and discussed. Keywords-real time; DSP; PID; state feedback;, brushed DC motor I. I NTRODUCTION DC motorsare the torquetransducer that converts electrical energy into mechanical energy. Therefore, they are one of the most widely used prime movers in industry. The torque required for the motion is developed on the motor shaft and it is directly proportional to the field flux and the armature current [1]. Recently, small size and high speed DC motors are produced based on developing technologies. The DC motors which have different power, size and speed values are widely usedin industrial applications such as automotive, trains, electric vehicle, robotic and automation. Furthermore, serial excited DC motor is commonly employed in some electric traction applications [2]. The brushed DC motors are one of the earliest designed and produced motors. The simplicity of design and theoretical substructure, besides conveniently speed and torque control features are the advantages of this type of motors. On the other hand, the controllability and reliability of DC motors reduces at low speeds. Besides, their dimensions are larger than AC motors which have the same power. Proportional-Integral-Derivative (PID) control is frequently used in industrial applications [3]. The most important advantages of PID control method are its simple structure and stability [4]. Despite these advantages, the basic problems of this method are the insensitivity to the systems having highly nonlinear components and easy effectiveness by disturbance [5]. In modern control, H control, sliding mode control, fuzzy logic, neural networks, state feedback control methods are used to reduce the nonlinear effectsof the system and parameter variation of the control algorithms [6 - 9]. In this study, real time DSP based PID and state feedb control methods are performed for position, trajectory speed variables. The obtained results are compared d various input signals for evaluating the performances control methods. II. M ATHEMATICAL M ODEL OF DCM OTOR In this study, a serial excited brushed DC motor is used evaluate performances of two well-known control algorith namely PID and state feedback control methods. The parameters are given in Table I. TABLE I. P ARAMETERS OF DC M OTOR U SED IN THE S TUDY Symbol Description Value J Inertia of the motor [kgm 2 ] 4.9e-6 R Armature resistance [] 5.5 L Armature inductance[H] 8.5e-4 K Motor constant [Nm/A] 4.1e-2 B Viscose damping [Mms/rad] 3.056e-4 The equivalent circuit of a serial excited brushed DC motor is shown Fig.1. The mathematical model of DC mot can be easily computed by using Kirchhoff current law: e dt di L Ri V + + = (1) where V is the supply voltage, R is the armature resistanc is the armature inductance, i is the armature current and the back electromotor force. The mechanical equation of DC motor can be give follows: T L T B dt d J = + + ω ω (2) where J is the moment of inertia, B is the viscose d Figure 1. Electric equivalent circuit of a brushed DC motor 978-1-4577-0746-9/11/$26.00 ©2011 IEEE