Soft switch circuit and control method, and power source assembly

A power source assembly, comprising a main circuit and a soft switch circuit, wherein

• the soft switch circuit comprises a switching voltage terminal, a main inductor, and a second voltage terminal, the switching voltage terminal being electrically connected to a first terminal of the main inductor, and the second voltage terminal being electrically connected to a second terminal of the main inductor, wherein the soft switch circuit further comprises an auxiliary module and a first voltage terminal, and the auxiliary module is connected in series between the switching voltage terminal and the first voltage terminal,
• the auxiliary module comprises an auxiliary inductor and a control unit which is connected in series to the auxiliary inductor, the auxiliary inductor is capable of generating magnetic coupling with the main inductor and generating a coupling voltage with the main inductor,
• the auxiliary module is configured to be charged with a first voltage input from the first voltage terminal and the coupling voltage generated with the main inductor when the switching voltage terminal receives a first level signal, so as to reduce a current flowing through the switching voltage terminal;
• and
• the auxiliary module is further configured to discharge to the switching voltage terminal when the switching voltage terminal receives a second level signal, wherein the first level signal and the second level signal are different from each other;
• wherein the control unit comprises an auxiliary switch element, and the auxiliary switch element is connected in series between the auxiliary inductor and the first voltage terminal, and
• the main circuit comprises a power source module, a total output capacitor, and a power output terminal, an output terminal of one of the power source module and a first electrode of the total output capacitor is electrically connected to the switching voltage terminal, an output terminal of the other of the power source module and the first electrode of the total output capacitor is electrically connected to the second voltage terminal, a positive electrode of the power output terminal is electrically connected to the first electrode of the total output capacitor, and a negative electrode of the power output terminal is electrically connected to a second electrode of the total output capacitor.

A control method for a soft switch circuit, wherein the soft switch circuit comprises a switching voltage terminal, a main inductor, and a second voltage terminal, the switching voltage terminal being electrically connected to a first terminal of the main inductor, and the second voltage terminal being electrically connected to a second terminal of the main inductor, wherein the soft switch circuit further comprises an auxiliary module and a first voltage terminal, and the auxiliary module is connected in series between the switching voltage terminal and the first voltage terminal,

• the auxiliary module comprises an auxiliary inductor and a control unit which is connected in series to the auxiliary inductor, the auxiliary inductor is capable of generating magnetic coupling with the main inductor and generating a coupling voltage with the main inductor,
• the auxiliary module is configured to be charged with a first voltage input from the first voltage terminal and the coupling voltage generated with the main inductor when the switching voltage terminal receives a first level signal, so as to reduce a current flowing through the switching voltage terminal;
• and
• the auxiliary module is further configured to discharge to the switching voltage terminal when the switching voltage terminal receives a second level signal, wherein the first level signal and the second level signal are different from each other;
• wherein the control unit comprises an auxiliary switch element, and the auxiliary switch element is connected in series between the auxiliary inductor and the first voltage terminal, and
• the control method comprises:
• when the switching voltage terminal receives the first level signal, controlling the auxiliary module to be charged with the first voltage input from the first voltage terminal, so as to reduce the current flowing through the switching voltage terminal;
• when the switching voltage terminal receives the second level signal, controlling the auxiliary module to discharge to the switching voltage terminal.