This paper proposed a plug-in multiple periodical fractional-order selective harmonic repetitive control (MP-FSHRC) scheme for a programmable ac power source to provoke multiperiodic high-quality output voltages, where multiperiodic SHRC are plugged into the deadbeat control loop scheme, so the proposed scheme exploits both multiperiodic SHRC and the deadbeat controller (DBC), in which the former provides fast response and good robustness, in the meantime, the multiperiodic SHRC offers accurate compensation of the multiperiodic signals. The stability criterion and parameter tuning principles are given for the analysis and synthesis of plug-in multiperiodic SHRC. More importantly, to improve compensation precision, the multiperiodic SHRC evolve into a fractional-order form—MP-FSHRC controller. Experimental results indicate that a programmable ac power source with the proposed scheme can produce multiperiodic voltages with satisfactory performance.