CN203722477U - New type switch power circuit topology structure - Google Patents

Abstract

The utility model relates to a new type switch power circuit topology structure comprising an input circuit, a fly-back topology circuit, a forward fly-back topology circuit and an output circuit. The fly-back topology circuit and the forward fly-back topology circuit comprise a transformer T1 and a transformer T2 separately. The input circuit, the transformer T1 primary winding and the transformer T2 primary winding are serially connected successively. The transformer T1 secondary winding and the transformer T2 secondary winding are connected in parallel on two ends of the output circuit. The fly-back topology circuit further comprises a diode D1. One end of the transformer T1 secondary winding is connected with the output end through the diode D1, and the other end of the transformer T1 secondary winding is grounded. Regardless of the switch-on or switch-off of a power VMOS tube, the transformer in the forward fly-back topology circuit is always used to transmit energy to loads, so the utilization rate and the load capacity of the transformer and the transmission power and the efficiency of a switch power source can be greatly improved.

Description

A kind of Novel switch power circuit topological structure

Technical field

The utility model relates to switch power technology field, is specifically related to a kind of Novel switch power circuit topological structure.

Background technology

Switching Power Supply is widely used in industry and national defence field, in the military-civil electronic systems such as space flight, aviation, boats and ships, weapons, railway, communication, medical electronics, industrial automation equipment, is used widely.Common switching power circuit topological structure has forward converter, circuit of reversed excitation, push-pull circuit, half-bridge circuit and full-bridge circuit topology etc.Each circuit topological structure all cuts both ways, and can be applicable to different occasions.

Single-ended input topological structure, because of simple in structure, is used widely in switching power circuit topology.Positive flyback topological circuit puts forward on forward converter and flyback topological circuit basis, and the in the situation that of same frequency and same magnetic scantling, its load capacity exceedes forward converter topology.Existing positive flyback topological circuit is the outputting inductance of forward converter to be moved on to input be connected in series with normal shock transformer, increases winding, allows inductance become flyback transformer.This mode allows normal shock transformer and flyback transformer all transfer energy to load, and load capacity exceedes forward topology circuit.But in this positive flyback topological circuit, in the time of the conducting of input circuit power VMOS tube, flyback transformer is made inductance, normal shock transformer transferring energy, and power VMOS tube by time, flyback transformer transferring energy, normal shock transformer is not utilized.This easily causes load transformer ability, utilance in Switching Power Supply topological circuit low.

Utility model content

The purpose of this utility model is to provide a kind of Novel switch power circuit topological structure, this structure is improved on positive circuit of reversed excitation basis, while having realized power VMOS tube conducting, normal shock transformer energy transferring energy is to load, and in the time that power VMOS tube ends, the energy that normal shock transformer and flyback transformer can store leakage inductance is delivered to load, and this not only can increase the load capacity of switching power circuit, can also improve the efficiency of switching power circuit.

For achieving the above object, the utility model has adopted following technical scheme: a kind of Novel switch power circuit topological structure, comprises input circuit, flyback topological circuit, positive flyback topological circuit and output loop; Described flyback topological circuit and positive flyback topological circuit comprise respectively transformer T1 and transformer T2; The armature winding of described input circuit, the armature winding of transformer T1 and transformer T2 is connected successively, and the secondary winding of the secondary winding of transformer T1 and transformer T2 is connected in parallel on output loop two ends.

Described input circuit comprises inductance L 1, capacitor C 1 and power VMOS tube V1; Described inductance L 1 one end drains and is connected with power VMOS tube, another termination power through the armature winding of transformer T1 and the armature winding of transformer T2; Described capacitor C 1 is connected in parallel on the armature winding of the transformer T1 connecting successively, armature winding and the power VMOS tube V1 two ends of transformer T2; Described power VMOS tube source electrode connects input ground.

Described flyback topological circuit comprises transformer T1 and diode D1, and secondary winding one end of described transformer T1 is connected with output through diode D1, another termination output ground.

Described positive flyback topological circuit comprises transformer T2, diode D2 and diode D3; The secondary winding two ends of described transformer T2 are connected output through diode D2 with diode D3 respectively, and the secondary winding centre cap of transformer T2 connects output ground.

From above technical scheme, in the utility model, in the time of power VMOS tube conducting in input circuit, the effect of flyback topological circuit is not only to its transformer storage power, and the primary winding also aligning in flyback topological circuit carries out chokes; The effect of positive flyback topological circuit is to load transmitting energy by its transformer.In the time that the power VMOS tube in input circuit ends, the effect of flyback topological circuit is to load transfer energy by its transformer; Positive flyback topological circuit still by transformer to load transmitting energy.By cooperatively interacting of flyback topological circuit and positive flyback topological circuit, realize no matter power VMOS tube conducting still ends, transformer in positive flyback topological circuit, all to load transmitting energy, has improved the utilance of transformer and through-put power and the efficiency of load capacity and Switching Power Supply greatly.

Brief description of the drawings

Fig. 1 is circuit theory diagrams of the present utility model.

Embodiment

Below in conjunction with accompanying drawing, the utility model is described further:

A kind of Novel switch power circuit topological structure as shown in Figure 1, comprises input circuit, flyback topological circuit, positive flyback topological circuit and output loop.Described input circuit comprises inductance L 1, capacitor C 1 and power VMOS tube V1.Described flyback topological circuit comprises transformer T1 and diode D1.Described positive flyback topological circuit comprises transformer T2, diode D2 and diode D3.Described output loop comprises capacitor C 2.

Further, as shown in Figure 1, the armature winding two ends of transformer T1 are respectively 1 end and 2 ends, and secondary winding two ends are respectively 3 ends and 4 ends.The armature winding two ends of transformer T2 are respectively 5 ends and 6 ends, and secondary winding two ends are respectively 7 ends and 9 ends, and centre tap lead-in wire is 8 ends.Wherein, 2 ends and 3 ends are Same Name of Ends, and 5 ends and 7 ends are Same Name of Ends, and 5 ends and 9 ends are different name end.

Further, as shown in Figure 1,1 end of described inductance L 1 one end and transformer T1 is connected, another termination power.2 ends of transformer T1 armature winding are connected with 5 ends of transformer T2 armature winding, and 6 ends of transformer T2 and the drain electrode of power VMOS tube are connected, and the source electrode of power VMOS tube connects input ground.Capacitor C 1 two ends are connected with 1 end of transformer T1 armature winding and the source electrode of power VMOS tube respectively.The anode of 3 terminating diode D1 of transformer T1 secondary winding, diode D1 negative electrode connects output; 4 termination output ground of transformer T1 secondary winding.The anode of 7 terminating diode D2 of transformer T2 secondary winding, diode D2 negative electrode connects output; The centre tap lead end 8 of transformer T2 secondary winding connects output ground; 9 terminating diode D3 anodes of transformer T2 secondary winding, diode D3 negative electrode connects output.The middle leads end 8 of capacitor C 2 one termination transformer T2 secondary winding, the other end is connected with the negative electrode of diode D1 and D2 respectively.

Operation principle of the present utility model is:

Basic functional principle of the present utility model is the same with normal shock or flyback transformer operation principle, conducting or the cut-off that produces high-frequency pulse signal and come power ratio control VMOS pipe by pulse width modulator, make input direct voltage be transformed into high-frequency pulse voltage, after transformer coupled, form output voltage by current rectifying and wave filtering circuit.Output is amplified and Coupled Feedback through error, and the duty ratio of regulation and control pulse width modulator, forms a closed-loop system, makes output voltage stabilization.

The utility model switching power circuit topological structure adopts flyback topological circuit and the positive combined mode of flyback topological circuit.For flyback topological circuit, in the time of the conducting of input circuit power VMOS tube, in flyback topological circuit, the secondary winding no current of transformer T1 passes through, and the armature winding of T1 not only carries out stored energy, and the armature winding that also aligns transformer T2 in flyback topological circuit carries out chokes.Transformer T1 in flyback topological circuit is the transformer in flyback topological circuit, is again the inductance in positive flyback topological circuit.If there is no transformer T1, can make power VMOS tube damage because electric current is excessive.In the time that input circuit power VMOS tube ends, the transformer T1 in flyback topological circuit provides energy to load.For positive flyback topological circuit, because the transformer T1 in flyback topological circuit is as the choke induction of positive flyback topological circuit, so without additional inductance.In the time of the conducting of input circuit power VMOS tube, transformer T2 provide energy to load.In the time that input circuit power VMOS tube ends, the energy that transformer T2 leakage inductance stores is transferred to load by diode D3.

Specifically, as shown in Figure 1, in the time of the conducting of input circuit power VMOS tube, the output voltage of transformer T1 secondary winding 4 ends is higher than 3 ends, and diode D1 ends, and transformer T1 not transferring energy arrives load, store energy in self, and the armature winding of transformer T2 is played to choking effect.Now, the output voltage of transformer T2 secondary winding 7 ends is higher than 8 ends, diode D2 conducting; The output voltage of 9 ends is lower than 8 ends, and diode D3 ends, and energy is transferred to load by transformer T2 and diode D2; While is because of the existence of transformer T2 leakage inductance, also stored energy of transformer T2 itself.In the time that input circuit power VMOS tube ends, the output voltage of transformer T1 secondary winding 3 ends is higher than 4 ends, diode D1 conducting, and the energy of transformer self storage is transferred to load by diode D1.Now, the output voltage of transformer T2 secondary winding 9 ends is higher than 8 ends, diode D3 conducting, and the voltage of transformer T2 secondary winding 7 ends is lower than 8 ends, diode D2 cut-off, the energy of transformer T2 self storage is transferred to load through diode D3.The utility model cooperatively interacts by flyback topological circuit and positive flyback topological circuit, realize no matter power VMOS tube conducting still ends, transformer in positive flyback topological circuit, all to load transmitting energy, has improved the utilance of transformer and through-put power and the efficiency of load capacity and Switching Power Supply greatly.

Above-described embodiment is described preferred implementation of the present utility model; not scope of the present utility model is limited; do not departing under the prerequisite of the utility model design spirit; various distortion and improvement that those of ordinary skill in the art make the technical solution of the utility model, all should fall in the definite protection range of the utility model claims.

Claims (4)

1. a Novel switch power circuit topological structure, is characterized in that: comprise input circuit, flyback topological circuit, positive flyback topological circuit and output loop; Described flyback topological circuit and positive flyback topological circuit comprise respectively transformer T1 and transformer T2; The armature winding of described input circuit, the armature winding of transformer T1 and transformer T2 is connected successively, and the secondary winding of the secondary winding of transformer T1 and transformer T2 is connected in parallel on output loop two ends.

2. a kind of Novel switch power circuit topological structure according to claim 1, is characterized in that: described input circuit comprises inductance L 1, capacitor C 1 and power VMOS tube V1; Described inductance L 1 one end drains and is connected with power VMOS tube, another termination power through the armature winding of transformer T1 and the armature winding of transformer T2; Described capacitor C 1 is connected in parallel on the armature winding of the transformer T1 connecting successively, armature winding and the power VMOS tube V1 two ends of transformer T2; Described power VMOS tube source electrode connects input ground.

3. a kind of Novel switch power circuit topological structure according to claim 1, it is characterized in that: described flyback topological circuit comprises transformer T1 and diode D1, secondary winding one end of described transformer T1 is connected with output through diode D1, another termination output ground.

4. a kind of Novel switch power circuit topological structure according to claim 1, is characterized in that:

Described positive flyback topological circuit comprises transformer T2, diode D2 and diode D3; The secondary winding two ends of described transformer T2 are connected output through diode D2 with diode D3 respectively, and the secondary winding centre cap of transformer T2 connects output ground.