Rotary machine drive system

A rotary machine drive system includes: a first heat source heat exchanger that receives a first heating medium and gasifies a liquid working medium; a first expander (13) that is connected to a rotation shaft and rotates the rotation shaft by expanding the working medium that has been gasified by the first heat source heat exchanger; a rotary machine that has a rotor part provided to the rotation shaft; a second heat source heat exchanger that receives a second heating medium and gasifies a liquid working medium; a second expander (14) that is connected to the rotation shaft and rotates the rotation shaft by expanding the second heating medium; and a condenser (22) that condenses the working medium that has been used in the first expander (13) and the working medium that has been used in the second expander (14).