Dc:dc power converter

An electrical power system (200, 300, 400) comprising:

• a DC:DC power converter (10, 10a, 10b) comprising a DC:AC converter circuit (11), an AC:DC converter circuit (12), and an AC link (13) that connects an AC side of the DC:AC converter circuit to an AC side of the AC:DC converter circuit and has an impedance synthesizer (14) connected therein, the impedance synthesizer comprising an active bridge circuit (140);
• and
• a control system (150) configured to:
• determine a desired impedance for the AC link;
• and
• control a switching operation of a plurality of power semiconductor switches (141L,H, 142L,H) of the active bridge circuit and thereby control an output voltage of the impedance synthesizer and an impedance of the AC link according to the desired impedance.

A method (500) of operating an electrical power system (200, 300, 400), the electrical power system comprising:

• a DC power source (203, 303, 403);
• a DC electrical network (201, 202, 301, 401);
• a DC:DC power converter (10) comprising a DC:AC converter circuit (11) connected, at a DC side, to the DC power source;
• an AC:DC converter circuit (12) connected, at a DC side, to the DC electrical network;
• an AC link (13) that connects an AC side of the DC:AC converter circuit to an AC side of the AC:DC converter circuit and has an impedance synthesizer (14) connected therein, the impedance synthesizer comprising an active bridge circuit (140);
• and
• a control system (150),
• the method (500) comprising:
• determining (510), by the control system, a desired impedance for the AC link;
• and
• controlling (540), by the control system, a switching operation of a plurality of power semiconductor switches (141L,H, 142L,H) of the active bridge circuit to control an output voltage of the impedance synthesizer and an impedance of the AC link according to the desired impedance.