An Adaptive Algorithm for Battery Charge Monitoring based on Frequency Domain Analysis

With technological advancement, the automobile industry is undergoing a design evolution. There has been an increase in the use of electrically actuated systems; electronics-based control systems, along with an increase in average power consumption. But such increased incorporation has been one of the main causes of roadside breakdowns. However, through the help of modelling and simulation manufacturers can evaluate vehicle operation; reduce their cost while achieving a competitive advantage in the automotive market. Here an automotive electrical system has been discussed. Its architecture consists of a battery, alternator, starter solenoid, and starter motor. Detailed modelling and simulation based on Simulink have been developed. Here charge level of automobile battery and its effect on the operational characteristics of an automobile has been considered and simulated in a MATLAB Simulink environment. First, a time-domain analysis has been made of the current response recorded from its maximum, minimum value, and slope characteristics. The response characteristics hence obtained are also analysed in the frequency domain through FFT analysis to obtain data characteristics in the frequency domain. A detailed analysis has been done at different levels of battery charge degradation to obtain a continuous data set for different states. The result shows significant changes both in time and frequency domain displaying discrimination in terms of DC and frequency components along with relative harmonics distortions enabling battery charge monitoring from starting transients. This method of response characteristics analysis helps in easier computation and in designing a system that can help with vehicle diagnosis and quality control.