Controlling operation of a converter circuit regulating power transfer between first and second voltage sources includes comparing a detected power value in the converter circuit with a power command value; determining a converter gain based on detected first and second voltage levels of the first and second voltage sources; and determining operation signals for transmitting to switches in the converter circuit during a steady state to control switching time and duration. When the detected power value differs from the power command value, the method includes determining values of two or more variables associated with adjustment of switching time and duration based on the detected first and second voltage levels; and determining operation signals to transmit to the switches during a power transition state based on the determined values of the two or more variables to adjust switching time and switching duration of the switches, thereby regulating power transition.