LLC (Logical Link Control) series resonance converter and drive method thereof

The invention discloses an LLC (Logical Link Control) series resonance converter and a drive method thereof. The LLC series resonance converter comprises a bridge circuit, a resonance circuit, a transformer and a rectifying circuit, wherein the bridge circuit is coupled to input voltage and comprises at least two first switches; the resonance circuit is coupled to the bridge circuit and driven by the first switches; the transformer is coupled to the resonance circuit; the rectifying circuit comprises two sub drive circuits which respectively comprise a second switch, a shut-off circuit and a pulse width processor; the second switches are coupled to two ends of a secondary side of the transformer and used for providing voltage output of the LLC series resonance converter; the shut-off circuits are used for providing shut-off signals for the second switches, and each shut-off circuit comprises a current transformer which is connected between the secondary side of the transformer and the two second switches in series and used for measuring the current of a source-drain electrode circuit branch, which flows through the second switches, to generate shut-off signals; and the pulse width processors are used for reducing the duty cycle of power switch drive signals of the primary side of the transformer at control ends of the first switches to obtain switch-on signals and provide the signals for the second switches.