| In recent years, the electric vehicle (EV) and hybrid electric vehicle (HEV) are becoming more common due to their economics. The electric vehicle runs on a battery, and the accurate determination of state of charge (SOC) of a battery is the utmost requirement to predict the performance of EVs and HEVs. The battery SOC, which describes the amount of charge left in the battery, is an important parameter, and the primary focus of this thesis is to accurately estimate battery SOC. Hardware selection, implementation of the system, and controlled charging of a battery in an embedded-controller is another objective of this thesis. This research is to facilitate easy integration of the SOC-determining system with fuzzy logic approach into the existing EV without changing any of its design.;The different methods to estimate state of charge of a battery (SOC) are direct measurement, bookkeeping, and adaptive systems. However, accurate estimation of SOC is a challenge due to factors like temperature, charge-discharge rates, hysteresis, temperature, and cell aging that affects the estimated SOC in a battery. The main objective of this thesis is to develop an SOC-determining method that is exempt of the above factors. This is achieved by pulse-interrogation of the battery by fuzzy logic expert system (FLES).;The fuzzy logic approach is an accurate and robust method in determining battery SOC. In this thesis, the battery is charged up to the maximum charging limit through controlled charging using Arduino Uno embedded controller. Then the pulse-interrogation of the battery is done by discharging the battery through an Arduino Due embedded controller. The pulse-response, which is a function of the battery-impedance, is captured into the Arduino Due controller. The recorded response used as input to the FLES is then embedded into the Arduino board. In this research, the FLES is modeled using C++ programming. Arduino supports all standard C and C++ functions. The FLES-estimated value of SOC is displayed on the PC connected to the embedded-controller. |
