| 摘要 |
A full voltage range LLC resonant converter and a control method thereof belong to an LLC resonant power conversion technical field. a current type primary ring current sampler (21) samples a primary ring current signal of an LLC resonant conversion circuit. the primary ring current signal is transmitted into a primary ring energy counter (23) connected with a rectifier (22) through rectification of the rectifier. when a bus voltage changes in the range from Vmax to 5%Vmax, an LLC resonant primary ring residual resonant energy value corresponding to a bus transient voltage value is immediately counted by the primary ring energy counter, and a stable energy waveform Vo is outputted. when the LLC resonant primary ring residual resonant energy value is reduced to a preset energy value, an energy comparator (24) outputs a control signal to control a corresponding electronic switch (s1,s2) of the LLC resonant conversion circuit to be turned off, so that the electronic switch corresponding to a next half operation period of the LLC resonant conversion circuit is in a zero voltage state when the electronic switch is turned on. A full voltage operation range of the LLC resonant converter is realized and the reliability thereof is fundamentally ensured, so that the LLC resonant converter can be designed into a solid state converter and the entire life of the converter is equal to that of a semi-permanent device. The converter can be widely applied to the industries such as a non-contact type charging station for electromobiles, electromagnetic induction heating, a switching power supply and the like. |
