This paper presents the steady-state characteristics of an isolated self-excited series connected synchronous generator (SESCSG) under different values of excitation capacitance. SESCSG is a wound-rotor induction generator with stator and rotor windings connected in series along with excitation capacitors. The frequency of the generated voltage is equal to half of the rotor speed. This paper proposes a per-phase equivalent-circuit approach based on a balanced three-phase induction-motor model to derive steady-state equations of an isolated SESCSG under different power-factor loading conditions. Experimental results obtained from a laboratory 1.1 kW induction machine are also performed to confirm the effectiveness of the proposed method.