Among the energy targets of the Vietnamese government, solar energy is expected to become the main source of renewable energy in the future. Solar energy is moving forward, with Vietnam outstripping Thailand and becoming the country that installed the largest capacity of solar power generation in Southeast Asia, reaching 16,362 MW in new installations in December 2021. In this study, we have experimentally analyzed and designed a capacity of 47.5 MW grid-connected photovoltaic plant mounted on the floatation system at Da Mi hydropower reservoir in Binh Thuan province. This was selected to be utilized as the first effort to develop the first large-capacity floating solar power plant on a hydroelectric reservoir in Vietnam. A detailed examination of the electrical analysis, including DC to DC converters, AC inverters to the transmission network, and PV module connectivity configurations, are in scope. The present research has the potential to make a contribution to the design of the DC electrical part, the AC electrical part, and the layout PV modules—Inverter—Floatation system—Floating bridge of FPV plants which are less described in the former articles. The performance of the plant after the first 2 years of operation has confirmed that it has met the expectations and exceeded the investor’s target, with the power output of the first 2 years being higher than the design by 102.58% to 105.59% and no serious damage has occurred to the equipment from 1 June 2019 to 31 August 2021.