MOTOR DRIVE SYSTEM

A motor drive system in which a plurality of generators (6 to 11) driven by mechanical power generation apparatuses (1 to 5) are connected in parallel to a common distribution bus (12), and plural power conversion devices (61) connected to the common distribution bus (12) and output an AC power of a variable amplitude and a variable frequency drive plural electric motors (23 to 27) that drive load machines (33 to 36). Each power conversion device (61) includes a frequency control device for controlling a frequency of the common distribution bus (12) to be a predetermined value by controlling an active power to be exchanged between each power conversion device (61) and the common distribution bus (12). The power conversion device (61) further includes a DC voltage control device for controlling so that an output DC voltage of a converter (81) may be a predetermined value by controlling an active power to be exchanged between each power conversion device (61) and each motor (23 to 27).