Improve the efficiency of switch power supply circuit and system method
Power consumption of switch power supply including by semiconductor switches, magnetic components and wiring of the parasitic resistance produced by the fixed loss and switching loss in the case of making the switch operation. For fixed loss, because it mainly depends on the nature of the element, so need through the component technology improvement to be suppressed. In terms of magnetic components, for both the skin effect and the effect of low loss adjacent wires winding method research has a long history. To reduce from the leakage inductance of the transformer switching surge caused by the switching loss, people developed a surge of energy regeneration function of buffer circuit and other new technology. The following is to improve the efficiency of switch power supply circuit and system method: the first method: ZVS ( Zero voltage switch) 佐( Zero current switch) Such as the method of using resonant switching to reduce switching loss. This is much effective to reduce the switching loss, but the problem is caused due to the peak current and peak voltage of fixed loss will increase. The second method: using represented by active clamp circuit on the verge of resonance ( 边缘共振) To reduce the switching loss. This method is to solve the problem and development of active buffer ( 有源阻尼器) , is a very practical way of ZVS; But, by the light load conditions of reactive current caused by the decline in efficiency that is one big flaw. The third way: by extending switch element conduction time to inhibit the method of peak current to reduce the loss. In this way, with the method of tapping sensor is effective, it can cope with a surge phenomenon caused by the leakage inductance. The fourth method: in the low voltage large current situation by improving the method of the synchronous rectifier circuit to reduce the loss. A two-part structure is to realize the synchronous rectifier circuit is one of the efficient work methods, it USES close to zero. 5 fixed time ratio, and the front of the converter to control the output voltage. It's & other; A two-part structure will be led to the decrease of the efficiency of the traditional mode of thinking, in the low voltage large current situation is very effective. The 5th kind of method: using the parallel structure of the converter to reduce the loss. Finally this method, as well as the connection of the converter circuit in parallel to, also can part adopts parallel structure like current multiplier.