Universal Journal of Electrical and Electronic Engineering 8(3): 41-49, 2021 http://www.hrpub.org DOI: 10.13189/ujeee.2021.080301 A Design of a Robust Analog PWM Solar Charge Controller for the Off-Grid Solar Home System: Fixed Frequency Current Control Mode Mohammad Shariful Islam Faculty of Electrical Engineering, IPSis, University Technology MARA (UiTM), 40450, Shah Alam, Selangor, Malaysia Received May 2, 2021; Revised August 18, 2021; Accepted September 21, 2021 Cite This Paper in the following Citation Styles (a): [1] Mohammad Shariful Islam , "A Design of a Robust Analog PWM Solar Charge Controller for the Off-Grid Solar Home System: Fixed Frequency Current Control Mode," Universal Journal of Electrical and Electronic Engineering, Vol. 8, No. 3, pp. 41 - 49, 2021. DOI: 10.13189/ujeee.2021.080301. (b): Mohammad Shariful Islam (2021). A Design of a Robust Analog PWM Solar Charge Controller for the Off-Grid Solar Home System: Fixed Frequency Current Control Mode. Universal Journal of Electrical and Electronic Engineering, 8(3), 41 - 49. DOI: 10.13189/ujeee.2021.080301. Copyright©2021 by authors, all rights reserved. Authors agree that this article remains permanently open access under the terms of the Creative Commons Attribution License 4.0 International License Abstract Solar Home System (SHS) is a stand-alone power solution in an isolated area where the national power grid connection is not accessible. Presently using the off-grid solar home system has one solar panel, one lead-acid batter, one PWM Solar charge controller, and 12V DC power operated lamp solutions, fan, television, radio. Various solar home system packages have been introduced so far, which have offered different product features with price variations. Solar home system size is small, so producing energy is insufficient to fulfill the customer's demand. This research paper presented a novel feature analog PWM solar charging techniques through the algorithm of the fixed frequency current mode controller, which also satisfy the requirements of existing off-grid solar home system users to reduce self-power consumption thus purchasing at an affordable cost. This design set up four periods voltage threshold points as a safeguard for the battery to consider battery voltage level, cable length resistance, battery internal resistance, and EMI (Electromagnetic Interference) effects. PWM solar charging improves the charging strategy by protecting against surge voltage and lightning. The study is divided into three sections: solar charging, regulating signals, and voltage comparator. Accordingly, high-sophisticated fixed-frequency current mode controllers are a noise-free switching gate drive signal with simulation data. The design feature also ignores the EMI (Electromagnetic Interference) noise impact on digital IC's input signals. Keywords PWM, Self-Power Consumption, Surge Voltage, Efficient Charging, Fixed Frequency Current Control Mode 1. Introduction The Charge Controller is a crucial instrument for the off-grid solar system and extending the life of the lead-acid battery. Solar charger, such as PWM solar charging device and MPPT (Maximum Power Point Tracker) solar charge controllers, are widely used for autonomous solar systems. The level of charge and discharge settings depend on the battery's power and scale: All are optimized for the extended battery life of the device. These devices have many features, such as LVD (low disconnection voltage level), HVD (disconnection high voltage level), LVR (reconnection low voltage load), HVR (reconnection low voltage load), etc. (reconnected high voltage charging). Because of device inadequacies, LVD (low voltage disconnection) and HVD (high voltage disconnection) protect the battery from deep discharge and extra charge. The cost of the solar charging controller depends on the charging devices' performance and efficiency.