International Conference on Engineering Technologies (ICENTE'19) Konya, Turkey, October 25-27, 2019 Design and Analysis of PI Controller Based Four-Quadrant DC Motor Drive with Bipolar and Unipolar Switching Methods K. TUTUNCU1 and R. OZCAN2 1 Selcuk University, Konya/Turkey, 2Selcuk University, Konya/Turkey, ktutuncu@selcuk.edu.tr recaiozcan@selcuk.edu.tr Abstract - In this study, the closed loop speed control of the separately excited Direct Current (DC) motor controlled by a four-quadrant DC motor drive circuit was performed in MATLAB / SIMULINK software. For this purpose, two control circuits were designed using PI controller. The first one is the bipolar switching circuit and the second one is the unipolar switching circuit. The control signals obtained from these circuits were applied to the single-phase four-quadrant DC chopper power circuit to drive the separately excited DC motor at reference speed. Comparison of the both switching methods has been implemented based on the data obtained from the simulation results of four- quadrant operation of the DC motor. As a result of the comparison, it has been seen that output voltage and frequency responses were better than the bipolar switching method (BSM) due to doubling of switching frequency of output voltage of the unipolar switching method (USM). Keywords - DC motor drive, PI Control, Four-quadrant operation, Bipolar switching, Unipolar switching I. I ntroduction N OWADAYS , DC motor drives are widely used in applications requiring deceleration, acceleration and reversal operation due to their simple structure and low cost. Four-quadrant DC motor drive systems are required for speed control and braking applications to be faster, more efficient and economical [1-4]. High performance is an important element for the industry. DC motors need to be controlled in industry where the high performance is important [5]. Some of these control methods are PI, PID, fuzzy logic, reference model, and artificial neural networks [6]. Advances in semiconductor technology have resulted in tremendous progress in power electronics. Thus, Pulse Width Modulation (PWM)-based applications for generating variable frequency and voltage have become popular [7]. There are various applications in the literature depending on circuit structures and control methods: speed control of chopper fed DC motor with PI and fuzzy logic proportional integral controllers [5], modeling and implementation of four-quadrant DC motor drive [1] and DC motor control application with double cycle support for electric vehicles [6]. In this study, closed loop speed control of the separately excited DC motor controlled by a four-quadrant DC motor drive circuit in MATLAB / SIMULINK software was performed by using BSM and USM, respectively. The PI controller was used in both switching methods. The rest of the study was organized as follows: Section 2 gives information about the concept of the study and the design of the control system. Section 3 shows the results of the simulations. The study was concluded in Section 4. II. METHODS A. Conceptualization 1) Four-Quadrant DC Chopper Power Circuit Full bridge (H-Bridge) is used for DC motor to operate in forward motoring, reverse motoring and braking (four- quadrant) [4]. The four-quadrant DC chopper circuit feeding the DC motor shown in Figure 1 was constructed using four semiconductor switches (IGBT). The circuit has two legs and each leg has two switches. One of the switches on the same leg of the circuit, operates with the turned on and the other switch turned off. Figure 1: Four-quadrant DC chopper power circuit By switching the IGBTs appropriately, the average values of the output voltage and current as well as the polarity can be set. This enables the DC motor to be operated in four-quadrant. This topology let the system has, the advantages such as rapid response and control flexibility [1]. Figure 2 shows the four- E-ISBN: 978-605-68537-9-1 298