A controller is installed in a vehicle. The vehicle includes an engine, rotary electric machine for power generation, rotary electric machine for propulsion, power storage device, inverter for power generation, and inverter for propulsion. The controller includes a drive control changing unit that changes drive control of at least one of the rotary electric machine for power generation and the rotary electric machine for propulsion, for reduction of a total value of a power-generation-side ripple current generated according to an operating state of the rotary electric machine for power generation, and a drive-side ripple current generated according to the operating state of the rotary electric machine for propulsion, when the total value is equal to or larger than a preset threshold value.