With rapid developments in the satellite data services market, the demand for low earth orbit (LEO) satellites is increasing. Advancements in designing lightweight satellites are essential to maximize profits from the mass production of LEO satellites in private companies. This article proposes a new direct charging control suitable for electrical power systems for lightweight and highly reliable LEO satellites. Moreover, an analysis of the proposed solar array regulator (SAR) in terms of weight, efficiency, and reliability is presented. Additionally, the advantages of the proposed SAR in terms of lifespan and state of health of Li-ion batteries are presented because the peak value of the battery charging current and the temperature changes during the battery charging operation are relatively small.