Method of controlling dc/dc converter, method of controlling dc/dc converter apparatus, and method of controlling driving operation of electric vehicle

A method of controlling a DC/DC converter disposed between a first power device and a second power device for energizing at least one switching device with given duty ratios, comprising the steps of:

• setting, as operation modes, at least two of a primary voltage control mode for controlling a primary voltage of the DC/DC converter which is associated with the first power device, a secondary voltage control mode for controlling a secondary voltage of the DC/DC converter which is associated with the second power device, and a current limiting mode for controlling the primary voltage or the secondary voltage in order to prevent a current which flows between the first power device and the second power device through the DC/DC converter from exceeding a threshold value;
• and
• when switching between said at least two operation modes, making a duty ratio in the operation mode before being switched and a duty ratio in the operation mode after being switched, continuous with respect to each other.