Diesel engine power plant, gas turbine power plant and steam turbine power plant are in common use in ship main propulsion power. These power plants have each advantage and disadvantage at mass, size, most high-power, economic ability, and maneuverability. But any single power is difficult to meet the requirement of improving the ships’ tactical performance, speed and maneuverability. In developing history of ship propulsion system, in order to solve the contradiction between full speed high-power and cruise economic ability, combined power plant form can change the performance of simple plant, which collected the advantage of all kinds of power plants. Here combined power plant form is two or more same or not the same type engine combine used or trade off. The combined power plant can not only supply total power for ships when cruising, but also be more economical. So this plant is used widely. This paper, designs a multi-module experiment-rig and introduces its composition, working principle and disposition scheme, and carried out the dynamic characteristic experiment of the CODAG power plant.