| 主权项 |
1. A driving apparatus for driving switching elements of a power conversion circuit, the power conversion circuit having a series connection of an upper-arm switching element and a lower-arm switching element, the series connection being electrically connected in parallel with a direct-current (DC) power source, the apparatus comprising:
an upper-arm drive control unit configured to turn on or off the upper-arm switching element by charging or discharging the charge on a switching control terminal of the upper-arm switching element, the upper-arm drive control unit being configured to set a dead time for preventing both of the upper-arm switching element and the lower-arm switching element from being ON, the dead time taking a positive value; and a lower-arm drive control unit configured to turn on or off the lower-arm switching element by charging or discharging the charge on a switching control terminal of the lower-arm switching element, the lower-arm drive control unit being configured to set the dead time for preventing both of the upper-arm switching element and the lower-arm switching element from being ON, wherein the upper-arm drive control unit comprises:
an upper-arm discharge-rate changing unit configured to, during on-operation of the upper-arm switching element, change a setting of discharge rate at which the charge on the switching control terminal of the upper-arm switching element is discharged;an upper-arm first determination unit configured to, during the on-operation of the upper-arm switching element, determine whether or not the dead time that occurs immediately after commencement of off-operation of the upper-arm switching element is greater than the dead time assumed at the time of designing the apparatus under the setting changed by the upper-arm discharge-rate changing unit; andan upper-arm shift unit configured to, if it is determined by the upper-arm first determination unit that the dead time occurring immediately after the commencement of the off-operation of the upper-arm switching element is greater than the dead time assumed at the time of designing the apparatus, delay commencement of off-operation of the upper-arm switching element so as to reduce a time difference between the commencement of the off-operation of the upper-arm switching element and commencement of on-operation of the lower-arm switching element, and the lower-arm drive control unit comprises:
a lower-arm discharge-rate changing unit configured to, during on-operation of the lower-arm switching element, change a setting of discharge rate at which the charge on the switching control terminal of the lower-arm switching element is discharged;a lower-arm first determination unit configured to, during the on-operation of the lower-arm switching element, determine whether or not the dead time that occurs immediately after commencement of off-operation of the lower-arm switching element is greater than the dead time assumed at the time of designing the apparatus under the setting changed by the lower-arm discharge-rate changing unit; anda lower-arm shift unit configured to, if it is determined by the lower-arm first determination unit that the dead time occurring immediately after the commencement of the off-operation of the lower-arm switching element is greater than the dead time assumed at the time of designing the apparatus, delay the commencement of the off-operation of the lower-arm switching element so as to reduce a time difference between the commencement of the off-operation of the lower-arm switching element and commencement of on-operation of the upper-arm switching element. |
