<p>This paper presents the design and research results of a PWM series resonant converter (SRC) with a primary variable input structure and a wide output voltage range. The demand for fast chargers with a wide output voltage range to cope with various electric vehicles (EVs) has recently increased. Previous studies have primarily used LLC resonant converters and pulse width modulation (PWM) full-bridge converters. However, designing a resonant tank for LLC resonant converters that satisfy a wide output voltage range is difficult. Conversely, obtaining a highly efficient design that support a wide output range for PWM full-bridge converters is difficult owing to high secondary rectifier voltage stress and circulating current. These shortcomings of LLC resonant and full-bridge converters are typically overcome by varying the input voltage and applying a changeover switch, such as a high-capacity direct current (DC) relay, at the secondary output stage. However, these techniques can result in increased costs and low reliability. Furthermore, in the case of LLC converters, the input voltage must be significantly varied to achieve gain. The input voltage of an LLC converter depends on the output voltage of the power factor correction (PFC) converter, limiting the fluctuation range of the AC line voltage. In this study, a PWM series resonant converter with a variable structure on the primary side is introduced to alleviate the limitations of previous studies. The proposed converter provides a wide output voltage range with a narrow input voltage variation of 50&#xa0;V or less without requiring a high-capacity changeover switch. The circuit was validated through experimental results obtained on a 35-kW-class prototype.</p>