A kind of DC power supplier
Technical field
The present invention relates to power supply, especially relate to a kind of DC power supplier.
Background technology
Existing DC power supplier generally all comprises input electromagnetic interference (the Electromagnetic Interference that connects step by step successively, abbreviation EMI) filter, power factor correction (PowerFactor Correction is called for short PFC) power stage, DC/DC transform power level.DC power supplier as shown in Figure 1 is a typical DC power supplier, and Vin is for exchanging or the DC power supply input among the figure, and R1 is load.Its PFC power stage circuit comprises the boosted switch power circuit that rectifier bridge B1 and does not isolate, be called for short the Boost circuit, wherein the Boost circuit is a most basic a kind of DC/DC topology, is provided with a switching tube S1 and a diode D1, or the soft switch circuit of deriving of its correspondence; The DC/DC circuit is a resonant circuit, comprises switching tube S3, S4, main transformer T1, resonating devices such as the Cr that connects with main transformer, Lr, and output rectifier diode D2, D3.The defective of this DC power supplier is: there is bigger loss in the power rectification bridge B1 of input, and rectifier diode D2, the D3 of output are power fast recovery diodes, also has bigger loss.Reason is that their ampacity is big, and forward conduction voltage drop generally all surpasses 1V, thereby causes the efficient of whole DC power supplier lower.
Summary of the invention
Technical problem to be solved by this invention is to solve the defective that above-mentioned prior art exists, and proposes a kind of DC power supplier.
Technical problem of the present invention is solved by the following technical programs.
This DC power supplier, comprise the electromagnetic interface filter that connects step by step successively, PFC power stage circuit and DC/DC transform power level circuit, described PFC power stage circuit comprises the Boost circuit, described DC/DC transform power level circuit comprises by switching tube, main transformer, resonant transform circuit that the resonating device that is connected with main transformer is formed and output rectifying tube, described switching tube is connected with the output of described PFC power stage circuit, described resonating device of connecting with main transformer is connected between the primary coil of described switching tube and described main transformer, and described output rectifying tube is connected with the secondary coil of described main transformer.
The characteristics of this DC power supplier are:
The Boost circuit of described PFC power stage is the non-bridge PFC circuits topology that comprises two single Boost circuit, and two single Boost circuit of described non-bridge PFC circuits topology are connected with two outputs of described electromagnetic interface filter respectively.Realize rectification and the function of boosting by the non-bridge PFC circuits topology, to improve the efficient of PFC power stage.
Technical problem of the present invention can be solved by following further technical scheme.
The one Boost circuit of described two single Boost circuit comprises first inductance, first diode and first switching tube, the positive pole of described first diode is connected with the drain electrode of first switching tube, the negative pole of described first diode is connected with an output of described PFC power stage, the source electrode of described first switching tube is connected with another output of described PFC power stage, one end of described first inductance is connected with the tie point of the drain electrode of first switching tube with the positive pole of described first diode, and the other end of described first inductance is connected with an output of described electromagnetic interface filter.
The 2nd Boost circuit of described two single Boost circuit comprises second inductance, second diode and second switch pipe, the positive pole of described second diode is connected with the drain electrode of second switch pipe, the negative pole of described second diode is connected with an output of described PFC power stage, the source electrode of described second switch pipe is connected with another output of described PFC power stage, one end of described second inductance is connected with the tie point of the drain electrode of second switch pipe with the positive pole of described second diode, and the other end of described second inductance is connected with another output of described electromagnetic interface filter.
Technical problem of the present invention also can be solved by following further technical scheme, adopts the switching tube of low on-resistance to substitute diode to eliminate the conduction loss of diode, further improves the efficient of PFC power stage circuit.
The one Boost circuit of described two single Boost circuit comprises first inductance, the 3rd switching tube and first switching tube, the source electrode of described the 3rd switching tube is connected with the drain electrode of first switching tube, the drain electrode of described the 3rd switching tube is connected with an output of described PFC power stage, the source electrode of described first switching tube is connected with another output of described PFC power stage, one end of described first inductance is connected with the tie point of the drain electrode of first switching tube with the source electrode of described the 3rd switching tube, and the other end of described first inductance is connected with an output of described electromagnetic interface filter.
The 2nd Boost circuit of described two single Boost circuit comprises second inductance, the 4th switching tube and second switch pipe, the source electrode of described the 4th switching tube is connected with the drain electrode of second switch pipe, the drain electrode of described the 4th switching tube is connected with an output of described PFC power stage, the source electrode of described second switch pipe is connected with another output of described PFC power stage, one end of described second inductance is connected with the tie point of the drain electrode of second switch pipe with the source electrode of described the 4th switching tube, and the other end of described second inductance is connected with another output of described electromagnetic interface filter.
Technical problem of the present invention can also be solved by following further technical scheme.
The output rectifying tube of described DC/DC transform power level circuit is the MOSFET of synchronous rectification, to improve the efficient of DC/DC transform power level.
Resonant transform circuit in the described DC/DC transform power level circuit is SRC resonant transform circuit or LLC resonant transform circuit.The SRC translation circuit is serial-resonant converter (SeriesResonant Converter is called for short SRC), and the LLC translation circuit is LLC pattern series resonant converter (LLC-Type Series Resonant Converter is called for short LLC).
The inductance in parallel with the primary coil of described main transformer is the inductance that is integrated in the main transformer in the described LLC resonant transform circuit.
Resonant transform circuit in the described DC/DC transform power level circuit is asymmetrical half-bridge SRC resonant transform circuit, symmetrical half bridge SRC resonant transform circuit, full-bridge SRC resonant transform circuit, asymmetrical half-bridge LLC resonant transform circuit, symmetrical half bridge LLC resonant transform circuit or full-bridge LLC resonant transform circuit.
Switching tube in the described DC/DC transform power level circuit is N type channel mosfet, P type channel mosfet, NPN type switch triode or positive-negative-positive switch triode.
The beneficial effect that the present invention is compared with the prior art is:
The present invention adopts the non-bridge PFC circuits topology at the PFC power stage circuit, adopt the MOSFET of synchronous rectification as efferent duct at DC/DC transform power level circuit, promoted the efficient of PFC power stage circuit and DC/DC transform power level circuit respectively significantly, loss can be reduced to original half, thereby the efficient of DC power supplier is promoted significantly.
Description of drawings
Fig. 1 is the circuit diagram of the DC power supplier of prior art;
Fig. 2 is the circuit diagram of the DC power supplier of the specific embodiment of the invention one;
Fig. 3 is the circuit diagram of the DC power supplier of the specific embodiment of the invention two;
Fig. 4 is the circuit diagram of the DC power supplier of the specific embodiment of the invention three;
Fig. 5 is the circuit diagram of the DC power supplier of the specific embodiment of the invention four;
Fig. 6 is the circuit diagram of the DC power supplier of the specific embodiment of the invention five.
Embodiment
The present invention is further illustrated in conjunction with embodiment for the contrast accompanying drawing below.
Embodiment one
DC power supplier as shown in Figure 2 comprises the electromagnetic interface filter 1, PFC power stage circuit 2 and the DC/DC transform power level circuit 3 that connect step by step successively.Vin is for exchanging or the DC power supply input among the figure, and R1 is load.
The Boost circuit of PFC power stage circuit 2 is the non-bridge PFC circuits topologys that comprise two single Boost circuit, and two single Boost circuit of described non-bridge PFC circuits topology are connected with two outputs of described electromagnetic interface filter respectively.
The one Boost circuit of two single Boost circuit, comprise first inductance L 1, the first diode D1 and the first switching tube MOSFET S1, the positive pole of the first diode D1 is connected with the drain electrode of the first switching tube MOSFET S1, the negative pole of the first diode D1 is connected with an output of PFC power stage, the source electrode of the first switching tube MOSFET S1 is connected with another output of PFC power stage, one end of first inductance L 1 is connected with the tie point of the positive pole of the first diode D1 with the drain electrode of the first switching tube MOSFET S1, and the other end of first inductance L 1 is connected with an output of electromagnetic interface filter.
The 2nd Boost circuit of two single Boost circuit, comprise second inductance L 2, the second diode D2 and second switch pipe MOSFET S2, the positive pole of the second diode D2 is connected with the drain electrode of second switch pipe MOSFET S2, the negative pole of the second diode D2 is connected with an output of PFC power stage, the source electrode of second switch pipe MOSFET S2 is connected with another output of PFC power stage, one end of second inductance L 2 is connected with the tie point of the positive pole of the second diode D2 with the drain electrode of second switch pipe MOSFET S2, and the other end of second inductance L 2 is connected with another output of electromagnetic interface filter.
DC/DC transform power level circuit, comprise by switching tube MOSFET S3, S4, main transformer T1, the resonating device Cr that is connected with main transformer T1, asymmetrical half-bridge SRC resonant transform circuit that Lr forms and output rectifying tube MOSFET S5, the S6 of synchronous rectification, switching tube MOSFETS3, S4 are connected with the output of Boost circuit, resonating device Cr, the Lr that connects with main transformer T1 is connected between the primary coil of switching tube MOSFET S3, S4 and main transformer T1, and output rectifying tube MOSFET S5, S6 are connected with the secondary coil of main transformer T1.
This embodiment one adopts the non-bridge PFC circuits topology at the PFC power stage circuit, adopt the MOSFET of synchronous rectification as efferent duct at DC/DC transform power level circuit, promoted the efficient of PFC power stage circuit and DC/DC transform power level circuit respectively significantly, thereby the efficient of DC power supplier is promoted significantly.
Embodiment two
DC power supplier as shown in Figure 3 with the circuit difference of embodiment one is: two single Boost circuit of non-bridge PFC circuits topology substitute the first diode D1, the second diode D2 respectively by the 3rd switching tube MOSFET S7, the 4th switching tube MOSFET S8.This embodiment two adopts the switching tube MOSFET of low on-resistance to substitute the conduction loss that diode can be eliminated diode, can further improve the efficient of PFC power stage circuit, and advantage is more outstanding.
Embodiment three
DC power supplier as shown in Figure 4 with the circuit difference of embodiment one is: switching tube MOSFET S3, the S4 in the DC/DC transform power level circuit, the main transformer T1 that is integrated with inductance L m, resonating device Cr, the Lr that is connected with main transformer T1 form asymmetrical half-bridge LLC resonant transform circuit.This embodiment three also can realize the function same with the circuit of embodiment one, and the efficient of DC power supplier has tangible lifting.
Embodiment four
DC power supplier as shown in Figure 5 with the circuit difference of embodiment one is: switching tube MOSFET S3, the S4 in the DC/DC transform power level circuit, the main transformer T1 that is integrated with inductance L m, the resonating device Cr1, the Cr2 that are connected with main transformer T1, Lr form symmetrical half bridge LLC resonant transform circuit.This embodiment four also can realize the function same with the circuit of embodiment one, and the efficient of DC power supplier has tangible lifting.
Embodiment five
DC power supplier as shown in Figure 6 with the circuit difference of embodiment one is: the switching tube MOSFET S3 in the DC/DC transform power level circuit, S4, S9, S10, the main transformer T1 that is integrated with inductance L m, resonating device Cr, the Lr that is connected with main transformer T1 form full-bridge LLC resonant transform circuit.This embodiment five also can realize the function same with the circuit of embodiment one, and the efficient of DC power supplier has tangible lifting.
Above content be in conjunction with concrete preferred implementation to further describing that the present invention did, can not assert that concrete enforcement of the present invention is confined to these explanations.For the general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, can also make some simple deduction or replace, all should be considered as belonging to protection scope of the present invention.