A motor drive device and motor drive system according to the present invention comprise: a power source terminal; a charging and discharging unit connected in series with the power source terminal; connection terminals to be connected to each of primary and secondary excitation coils for an anti-symmetric two phase motor; and a drive control unit which has a plurality of switching elements and respectively forms first and second paths by turning these switching elements on and off. The first path is used for independently supplying power to the respective primary and secondary excitation coils from the power source terminal via the connection terminals, and the second path is used for independent regeneration of each residual energy remaining in the primary and secondary excitation coils from the respective primary and secondary excitation coils into the charging and discharging unit via the connection terminals.