Control apparatus, vehicle system, and control method

A control method including:

• controlling an inverter which outputs electric power to an electric motor;
• obtaining an electric motor drive torque of the electric motor, a rotation number of the electric motor, and a DC voltage of the electric motor by way of a current sensor, a voltage sensor, and a rotation angle sensor;
• determining which one of a one-pulse control and a pulse-width modulation control is employed as a control method of the inverter in accordance with a predetermined condition based on the electric motor drive torque of the electric motor, the rotation number of the electric motor, and the DC voltage of the electric motor;
• determining whether phase sensor error information is calculable based on sensor learning information that specifies a relationship between a physical reference angle of a rotor of the electric motor and a phase angle of an output signal of the rotation angle sensor attached to the electric motor;
• and
• determining which one of the one-pulse control and the pulse-width modulation control is employed in accordance with the predetermined condition in a case where it is determined that the phase sensor error information is calculable.