Design and Implementation Of Battery Back-Up System for V/F Drive Application

Abstract

The battery back-up is similar to the UPS for any conventional system. Battery back-up is especially for the small power motor drives, where it is impractical to use the separate diesel generator set as fast response and economy point of view. Continuous availability of secured power supply is key factor for smooth plant operation. Due to higher load demands, the reliability of supply utility is a vital problem for continuous process industry as well as some critical applications. The main aim of this thesis is to develop maximum different possible solutions for the battery back-up system. Then by simulating all the available options, find out best suitable system, which can meet the industrial requirement. The main aim of the study is to reduce the no. of batteries connected in series to develop dc link, as more no. of batteries in series increases the problem of charge equalization and also increases initial cost and maintenance. The report contains the study of different charging methods of battery. Detailed study of the battery model is included. State of charge estimation of battery helps in increasing battery life. The report contains the simulation of phase shifted isolated full bridge boost converter for dc-to-dc power conversion application. Also linear firing scheme for thyristor rectifier is done with PSIM software. The whole circuit is simulated with the help of DLL block, which will help while preparing algorithm for DSP. Then for hardware implementation necessary pulse patterns are generated with DSP. After that design of necessary high frequency transformer is included. First hardware implementation of isolated boost converter is carried out. Trouble shooting with the hardware setup is done by modifying hardware and also software. At the end hardware implementation of battery charger is done. All necessary hardware results and images of setup are included in the thesis.