A method of operating a dc/dc converter

A programmed controller for a DC/DC converter, wherein the DC/DC converter comprises a primary side, a secondary side, and a transformer with a centre tap, wherein an upper transformer tap and a lower transformer tap are connected via a full-bridge circuit with upper switches onto an upper terminal point of a snubber capacitance and with lower switches onto a lower terminal point of the snubber capacitance, a lower secondary-side DC terminal is connected onto the lower terminal point of the snubber capacitance and an upper secondary-side DC terminal is connected onto the centre ta via a filter inductance, wherein the controller controls:

• in a first operating state the lower switches in an alternating manner and with a duty cycle d of between zero and 0.5 to apply positive voltage pulses of a secondary voltage to between the centre tap and the lower secondary-side DC terminal,
• wherein between these voltage pulses the lower switches are closed and the u er switches divert currents which on switching off the lower switches would lead to voltage peaks, into the snubber capacitance;
• and
• in a second operating state the upper switches in an alternating manner to apply positive voltage pulses of the secondary voltage to between the centre tap and the upper terminal point of the snubber capacitance,
• wherein between the voltage pulses the upper switches are closed and the lower switches are opened.

A DC/DC converter comprising a primary side, a secondary side, and a transformer with a centre tap, wherein an upper transformer tap and a lower transformer tap are connected via a full-bridge circuit with upper switches onto an upper terminal point of a snubber capacitance and with lower switches onto a lower terminal point of the snubber capacitance, a lower secondary-side DC terminal is connected onto the lower terminal point of the snubber capacitance and an upper secondary-side DC terminal is connected onto the centre tap via a filter inductance, wherein:

• in a first operating state the lower switches in an alternating manner and with a duty cycle d of between zero and 0.5 apply positive voltage pulses of a secondary voltage to between the centre tap and the lower secondary-side DC terminal,
• wherein between these voltage pulses the lower switches are closed and the upper switches divert currents which on switching off the lower switches would lead to voltage peaks, into the snubber capacitance;
• and
• in a second operating state the upper switches in an alternating manner apply positive voltage pulses of the secondar voltage to between the centre ta and the upper terminal point of the snubber capacitance,
• wherein between the voltage pulses the upper switches are closed and the lower switches are opened.