A power system has a first control apparatus configured to generating a first command signal and a second command signal, to control the first converter on the basis of the first command signal, and to transmit the second command signal to a second control apparatus and the second control apparatus configured to control the second converter on the basis of the received second command signal. When it is requested that a state of each of the first and second converters is changed from a first state to a second state, the first control apparatus generates the first and second command signals so that the state of the second converter is changed to a third state in which both of the upper arm and the lower arm keep being in the OFF state, then the state of the first converter is changed from the first state to the second state, and then the state of the second converter is changed from the third state to the second state.