http://www.iaeme.com/IJEET/index.asp 278 editor@iaeme.com International Journal of Electrical Engineering and Technology (IJEET) Volume 12, Issue 3, March 2021, pp. 278-288, Article ID: IJEET_12_03_036 Available online at http://www.iaeme.com/ijeet/issues.asp?JType=IJEET&VType=12&IType=3 ISSN Print: 0976-6545 and ISSN Online: 0976-6553 DOI: 10.34218/IJEET.12.3.2021.036 © IAEME Publication Scopus Indexed FPGA BASED IMPROVED CONTROL SCHEME FOR A BUCK CONVERTER Sonali Pandit Assistant Professor, Electrical and Electronics Engineering, Goa College of Engineering, Farmagudi, Ponda, Goa, India Vinayak Shet Professor, Electrical and Electronics Engineering, Goa College of Engineering, Farmagudi, Ponda, Goa, India ABSTRACT Buck converters are extensively used in modern applications. The closed loop control plays a crucial role in regulating the output voltage. This paper analyses a buck converter using a state space modeling approach. The transfer function is derived and the compensation is designed using an analog PI controller in the frequency domain. The design is verified using Matlab Simulink platform for time and frequency domain characteristics. The discrete PI controller is designed from the analog controller. The VLSI platform using FPGA technology is used to design the feedback loop of digital PI controller and improve the performance. The hardware is implemented on a Xilinx Spartan-3 FPGA. The Buck converter is tested with the feedback loop and the performance is analysed. Keywords: Buck converter, state space modeling, PI compensator, Digital PI controller, control, feedback loop, VLSI, FPGA Cite this Article: Sonali Pandit and Vinayak Shet, FPGA Based Improved Control Scheme for a Buck Converter, International Journal of Electrical Engineering and Technology (IJEET), 12(3), 2021, pp.278-288. http://www.iaeme.com/IJEET/issues.asp?JType=IJEET&VType=12&IType=3 1. INTRODUCTION DC-DC converters are used extensively in modern gadgets like laptops, mobile phone, chargers. They are having the advantages of single stage conversion and high efficiency. They can be classified as buck, boost or buck-boost. This paper focuses on a buck converter which is a step down converter where in the output voltage is less than the input voltage [1][2][3]. A mathematical modeling of the controller is useful for stability analysis and control of closed loop systems. There are various methods to model a buck converter [2]. A state space modeling approach is carried out to model the closed loop characteristics [4]. To regulate the output voltage of the converter a closed loop control using a suitable controller is required. The