A kind of cascade buck-boost type DC-DC converter
Technical field
The present invention relates to DC-DC (DC-DC) converter, especially one kind, to output and input electric current continuous and input
With the cascade buck-boost type DC-DC converter of output voltage same polarity, it can be used as basic unit and set up multi input and multi output
DC power system, such as: DC power supplier parallel system, LED array drive system, distributed photovoltaic power generation system.
Background technique
The existing basic DC-DC converter with stepping functions include One Buck-Boost converter body, Cuk converter,
Sepic converter and Zeta converter.As listed in table 1, in the case where not considering output capacitance, above-mentioned this 4 kinds have lifting
The basic DC-DC converter of pressure function is all unsatisfactory for " output and input electric current continuous and output and input voltage same polarity "
It is required that.
Table 1
By the way of cascading basic DC-DC converter, Boost and Buck converter are cascaded, can be obtained
It is continuous and output and input the buck-boost type DC-DC converter of voltage same polarity that electric current must be output and input, but a combination thereof
There are the discontinuous problems of electric current for inside.
Summary of the invention
In order to overcome the buck-boost type DC- of existing " output and input electric current continuous and output and input voltage same polarity "
There are the discontinuous problem of electric current inside the combination of Boost and Buck in DC converter concatenated schemes, the present invention provides a kind of grade
The buck-boost type DC-DC converter of connection, can be realized output and input that electric current is continuous, electric current is still continuous between grade and input and
Output common ground expands the type of buck-boost type DC-DC converter with this.
The technical solution adopted by the present invention to solve the technical problems is:
A kind of cascade buck-boost type DC-DC converter, including inductance L1 to inductance L3,1 booster type capacitive energy storage mould
Block, 1 voltage-dropping type capacitive energy storage module and capacitor Co, booster type capacitive energy storage module have port Via+, port Voa+ and end
Mouth Gnda, voltage-dropping type capacitive energy storage module have port Vib+, port Vob+ and port Gndb, one end of inductance L1 and direct current
The anode of source Vi is connected, and the other end of inductance L3 is connected with one end of one end of capacitor Co and load Z simultaneously, loads the another of Z
End simultaneously with the other end of capacitor Co, the negative terminal of DC power supply Vi, booster type capacitive energy storage module port Gnda and voltage-dropping type
The port Gndb of capacitive energy storage module is connected, and the rest part of booster type capacitive energy storage module and voltage-dropping type capacitive energy storage module is inserted
Enter inductance L1 between inductance L3 and in series relationship;
The booster type capacitive energy storage module includes diode Da_1, capacitor Ca_1, diode Da_2 and electronic switch Sa,
The electronic switch Sa has port c and port d, the anode of diode Da_1 while the port with booster type capacitive energy storage module
Via+ is connected with the port c of electronic switch Sa, the cathode of diode Da_1 one end with capacitor Ca_1 and booster type capacitor simultaneously
The port Voa+ of energy-storage module is connected, the port d of electronic switch Sa simultaneously with the other end of capacitor Ca_1 and diode Da_2
Anode is connected, and the cathode of diode Da_2 is connected with the port Gnda of booster type capacitive energy storage module;
The voltage-dropping type capacitive energy storage module includes diode Db_1, capacitor Cb_1, diode Db_2 and electronic switch Sb,
The electronic switch Sb has port e and port f, one end of capacitor Cb_1 while the port with voltage-dropping type capacitive energy storage module
Vib+ is connected with the port e of electronic switch Sb, the other end of capacitor Cb_1 while anode and diode Db_ with diode Db_1
2 cathode is connected, the cathode of diode Db_1 simultaneously with the port Vob+ and electronic switch Sb of voltage-dropping type capacitive energy storage module
Port f is connected, and the anode of diode Db_2 is connected with the port Gndb of voltage-dropping type capacitive energy storage module.
A kind of preferred connection type is: the port Via+ phase of the other end of inductance L1 and booster type capacitive energy storage module
Even, the port Voa+ of booster type capacitive energy storage module is connected with one end of inductance L2, the other end and voltage-dropping type capacitor of inductance L2
The port Vib+ of energy-storage module is connected, and the port Vob+ of voltage-dropping type capacitive energy storage module is connected with one end of inductance L3.
When electronic switch Sa cut-off, diode Da_1 conducting, DC power supply Vi, inductance L1, diode Da_1, inductance L2
With one circuit of voltage-dropping type capacitive energy storage module composition, DC power supply Vi, inductance L1, diode Da_1, capacitor Ca_1 and two poles
Pipe Da_2 constitutes another circuit.
When electronic switch Sa conducting, diode Da_1 cut-off, DC power supply Vi, inductance L1, electronic switch Sa and two poles
Pipe Da_2 constitutes a circuit, DC power supply Vi, inductance L1, electronic switch Sa, capacitor Ca_1, inductance L2 and the storage of voltage-dropping type capacitor
It can another circuit of module composition.
When electronic switch Sb cut-off when, diode Db_1 conducting, booster type capacitive energy storage module, inductance L2, capacitor Cb_1,
Diode Db_1, inductance L3, capacitor Co and load Z constitute a circuit, diode Db_2, diode Db_1, inductance L3, capacitor
Co and load Z constitute another circuit.
When electronic switch Sb conducting, diode Db_1 cut-off, booster type capacitive energy storage module, inductance L2, electronic switch
Sb, inductance L3, capacitor Co and load Z constitute a circuit, diode Db_2, capacitor Cb_1, electronic switch Sb, inductance L3, electricity
Hold Co and load Z constitutes another circuit.
Another preferred connection type is: the port Vib+ phase of the other end of inductance L1 and voltage-dropping type capacitive energy storage module
Even, the port Vob+ of voltage-dropping type capacitive energy storage module is connected with one end of inductance L2, the other end and booster type capacitor of inductance L2
The port Via+ of energy-storage module is connected, and the port Voa+ of booster type capacitive energy storage module is connected with one end of inductance L3.
When electronic switch Sb cut-off, diode Db_1 conducting, DC power supply Vi, inductance L1, capacitor Cb_1, diode
Db_1, inductance L2 and one circuit of booster type capacitive energy storage module composition, diode Db_2, diode Db_1, inductance L2 and liter
Another circuit of die mould capacitive energy storage module composition.
When electronic switch Sb conducting, diode Db_1 cut-off, DC power supply Vi, inductance L1, electronic switch Sb, inductance L2
With one circuit of booster type capacitive energy storage module composition, diode Db_2, capacitor Cb_1, electronic switch Sb, inductance L2 and boosting
Another circuit of type capacitive energy storage module composition.
When electronic switch Sa cut-off, diode Da_1 conducting, voltage-dropping type capacitive energy storage module, inductance L2, diode Da_
1, inductance L3, capacitor Co and load Z constitute a circuit, voltage-dropping type capacitive energy storage module, inductance L2, diode Da_1, capacitor
Ca_1 and diode Da_2 constitute another circuit.
When electronic switch Sa conducting, diode Da_1 cut-off, voltage-dropping type capacitive energy storage module, inductance L2, electronic switch
Sa and diode Da_2 constitutes a circuit, voltage-dropping type capacitive energy storage module, inductance L2, electronic switch Sa, capacitor Ca_1, inductance
L3, capacitor Co and load Z constitute another circuit.
Further, electronic switch Sa uses the electronic switch of one-way conduction, i.e. its electric current is from end when electronic switch Sa is connected
Mouth c is flowed into and is flowed out from port d;Electronic switch Sb uses the electronic switch of one-way conduction, i.e. Shi Qi electricity is connected in electronic switch Sb
Stream is flowed into from port e and is flowed out from port f.The preferred embodiment is electric current reflux in order to prevent.
Further, the electronic switch Sa includes diode Da_3, N-type metal-oxide-semiconductor Ma_1 and controller a, the control
Device a has port vga, and the anode of diode Da_3 is connected with the port c of the electronic switch Sa, the cathode of diode Da_3 and
The drain electrode of N-type metal-oxide-semiconductor Ma_1 is connected, and the source electrode of N-type metal-oxide-semiconductor Ma_1 is connected with the port d of the electronic switch Sa, N-type metal-oxide-semiconductor
The gate pole of Ma_1 is connected with the port vga of the controller a;
The electronic switch Sb includes that diode Db_3, N-type metal-oxide-semiconductor Mb_1 and controller b, the controller b have end
Mouth vgb, the anode of diode Db_3 are connected with the port e of the electronic switch Sb, the cathode and N-type metal-oxide-semiconductor of diode Db_3
The drain electrode of Mb_1 is connected, and the source electrode of N-type metal-oxide-semiconductor Mb_1 is connected with the port f of the electronic switch Sb, the door of N-type metal-oxide-semiconductor Mb_1
Pole is connected with the port vgb of the controller b.
The controller a determines the working condition of N-type metal-oxide-semiconductor Ma_1, and controller b determines the work shape of N-type metal-oxide-semiconductor Mb_1
State, the controller a and controller b are all made of power supply control chip.
Further, the phase of the output signal vgsa and vgsb of controller a and controller b successively lag the angle of setting
The value range of θ, θ are 0 to 2 π.
Technical concept of the invention are as follows: use 3 inductance by booster type capacitive energy storage module and voltage-dropping type capacitive energy storage mould
Block cascades up, and has not only realized efficient buck transformation, but also realizes that electric current is continuous between continuous input current, grade, exports electric current
Continuously, it outputs and inputs total ground and output voltage polarity is constant.
Beneficial effects of the present invention are mainly manifested in: the cascade buck-boost type DC-DC converter circuit structure is simple,
Applicable control method multiplicity has high efficiency, outputs and inputs continuous electric current, output and input voltage altogether and polarity one
It causes, output voltage Vo is greater than, less than or equal to the operating characteristic of direct current power source voltage Vi.
Detailed description of the invention
Fig. 1 is a kind of circuit diagram of the invention.
Fig. 2 is another circuit diagram of the invention.
Fig. 3 be in the present invention controller 1 to the timing diagram of controller n output signal.
Fig. 4 is simulation work waveform diagram of the embodiment of the present invention 1 under conditions of θ=0.
Fig. 5 is simulation work waveform diagram of the embodiment of the present invention 1 under conditions of θ=π.
Fig. 6 is simulation work waveform diagram of the embodiment of the present invention 2 under conditions of θ=0.
Fig. 7 is simulation work waveform diagram of the embodiment of the present invention 2 under conditions of θ=π.
Specific embodiment
The invention will be further described below in conjunction with the accompanying drawings.
Embodiment 1
With reference to Fig. 1 and Fig. 3~Fig. 5, a kind of cascade buck-boost type DC-DC converter, including inductance L1 is to inductance L3,1
A booster type capacitive energy storage module, 1 voltage-dropping type capacitive energy storage module and capacitor Co, booster type capacitive energy storage module have port
Via+, port Voa+ and port Gnda, voltage-dropping type capacitive energy storage module have port Vib+, port Vob+ and port Gndb, electricity
One end of sense L1 is connected with the anode of DC power supply Vi, the other end of inductance L3 and meanwhile with one end of capacitor Co and load Z one
End be connected, load Z the other end simultaneously with the other end of capacitor Co, the negative terminal of DC power supply Vi, booster type capacitive energy storage module
Port Gnda be connected with the port Gndb of voltage-dropping type capacitive energy storage module, booster type capacitive energy storage module and voltage-dropping type capacitor storage
The rest part of energy module is inserted into inductance L1 between inductance L3 and in series relationship, the other end and booster type capacitor of inductance L1
The port Via+ of energy-storage module is connected, and the port Voa+ of booster type capacitive energy storage module is connected with one end of inductance L2, inductance L2
The other end be connected with the port Vib+ of voltage-dropping type capacitive energy storage module, the port Vob+ and inductance of voltage-dropping type capacitive energy storage module
One end of L3 is connected.
The booster type capacitive energy storage module includes diode Da_1, capacitor Ca_1, diode Da_2 and electronic switch Sa,
The electronic switch Sa has port c and port d, the anode of diode Da_1 while the port with booster type capacitive energy storage module
Via+ is connected with the port c of electronic switch Sa, the cathode of diode Da_1 one end with capacitor Ca_1 and booster type capacitor simultaneously
The port Voa+ of energy-storage module is connected, the port d of electronic switch Sa simultaneously with the other end of capacitor Ca_1 and diode Da_2
Anode is connected, and the cathode of diode Da_2 is connected with the port Gnda of booster type capacitive energy storage module.
The voltage-dropping type capacitive energy storage module includes diode Db_1, capacitor Cb_1, diode Db_2 and electronic switch Sb,
The electronic switch Sb has port e and port f, one end of capacitor Cb_1 while the port with voltage-dropping type capacitive energy storage module
Vib+ is connected with the port e of electronic switch Sb, the other end of capacitor Cb_1 while anode and diode Db_ with diode Db_1
2 cathode is connected, the cathode of diode Db_1 simultaneously with the port Vob+ and electronic switch Sb of voltage-dropping type capacitive energy storage module
Port f is connected, and the anode of diode Db_2 is connected with the port Gndb of voltage-dropping type capacitive energy storage module.
Further, electric current reflux, electronic switch Sa use the electronic switch of one-way conduction, i.e. electronic switch Sa in order to prevent
Its electric current is flowed into from port c and is flowed out from port d when conducting;Electronic switch Sb uses the electronic switch of one-way conduction, i.e. electronics
Its electric current is flowed into from port e and is flowed out from port f when switch Sb is connected.
Further, the electronic switch Sa includes diode Da_3, N-type metal-oxide-semiconductor Ma_1 and controller a, the control
Device a has port vga, and the anode of diode Da_3 is connected with the port c of the electronic switch Sa, the cathode of diode Da_3 and
The drain electrode of N-type metal-oxide-semiconductor Ma_1 is connected, and the source electrode of N-type metal-oxide-semiconductor Ma_1 is connected with the port d of the electronic switch Sa, N-type metal-oxide-semiconductor
The gate pole of Ma_1 is connected with the port vga of the controller a;
The electronic switch Sb includes that diode Db_3, N-type metal-oxide-semiconductor Mb_1 and controller b, the controller b have end
Mouth vgb, the anode of diode Db_3 are connected with the port e of the electronic switch Sb, the cathode and N-type metal-oxide-semiconductor of diode Db_3
The drain electrode of Mb_1 is connected, and the source electrode of N-type metal-oxide-semiconductor Mb_1 is connected with the port f of the electronic switch Sb, the door of N-type metal-oxide-semiconductor Mb_1
Pole is connected with the port vgb of the controller b.
The controller a determines the working condition of N-type metal-oxide-semiconductor Ma_1, and controller b determines the work shape of N-type metal-oxide-semiconductor Mb_1
State, the controller a and controller b are all made of conventional power supply control chip, such as: UC3842 etc. can be used in controller a, control
The combination of UC3842 and IR2110 etc. can be used in device b processed.
Further, the phase of the output signal vgsa and vgsb of controller a and controller b successively lag the angle of setting
The value range of θ, θ are 0 to 2 π.
When embodiment 1 is in continuous conduction mode (CCM), steady operation process includes following multiple stages.
(1) when N-type metal-oxide-semiconductor Ma_1 end when, diode Da_1 conducting, DC power supply Vi, inductance L1, diode Da_1,
One circuit inductance L2 and voltage-dropping type capacitive energy storage module composition, DC power supply Vi, inductance L1, diode Da_1, capacitor Ca_1
Another circuit is constituted with diode Da_2.At this point, Ca_1 charges, L1 puts magnetic, and the working condition of L2 and voltage-dropping type capacitor store up
The working condition of energy module is related.
(2) when N-type metal-oxide-semiconductor Ma_1 is connected, diode Da_1 cut-off, DC power supply Vi, inductance L1, diode Da_3, N
Type metal-oxide-semiconductor Ma_1 and diode Da_2 constitutes a circuit, DC power supply Vi, inductance L1, diode Da_3, N-type metal-oxide-semiconductor Ma_
1, capacitor Ca_1, inductance L2 and another circuit of voltage-dropping type capacitive energy storage module composition.At this point, Ca_1 discharges, L1 magnetizes, and L2
Working condition it is related to the working condition of voltage-dropping type capacitive energy storage module.
(3) when N-type metal-oxide-semiconductor Mb_1 ends, diode Db_1 conducting, booster type capacitive energy storage module, inductance L2, capacitor
Cb_1, diode Db_1, inductance L3, capacitor Co and load Z constitute a circuit, diode Db_2, diode Db_1, inductance
L3, capacitor Co and load Z constitute another circuit.At this point, Cb_1 charges, L3 puts magnetic.
(4) when N-type metal-oxide-semiconductor Mb_1 is connected, diode Db_1 cut-off, booster type capacitive energy storage module, inductance L2, two poles
Pipe Db_3, N-type metal-oxide-semiconductor Mb_1, inductance L3, capacitor Co and load Z constitute a circuit, diode Db_2, capacitor Cb_1, two poles
Pipe Db_3, N-type metal-oxide-semiconductor Mb_1, inductance L3, capacitor Co and load Z constitute another circuit.At this point, Cb_1 discharges, L3 magnetizes.
Fig. 4 is simulation work waveform diagram of the embodiment 1 under conditions of θ=0.Fig. 5 is embodiment 1 under conditions of θ=π
Simulation work waveform diagram.By Fig. 4 and Fig. 5 it is found that the input current ii of embodiment 1 is continuous, output electric current iob is continuous, between grade
Electric current ioa is also continuous, and output voltage Vo, which can be greater than, is also smaller than direct current power source voltage Vi, Vo and Vi altogether and same polarity.Comparison
Fig. 4 and Fig. 5 is it is found that there is influence to the ripple of ii, ioa and iob in θ.
Embodiment 2
With reference to Fig. 2, Fig. 3, Fig. 6 and Fig. 7, a kind of cascade buck-boost type DC-DC converter, the other end and drop of inductance L1
The port Vib+ of die mould capacitive energy storage module is connected, one end phase of the port Vob+ and inductance L2 of voltage-dropping type capacitive energy storage module
Even, the other end of inductance L2 is connected with the port Via+ of booster type capacitive energy storage module, the port of booster type capacitive energy storage module
Voa+ is connected with one end of inductance L3.
Remaining structure and embodiment 1 of embodiment 2 are identical.
When embodiment 2 is in continuous conduction mode (CCM), steady operation process includes following multiple stages.
(1) when N-type metal-oxide-semiconductor Mb_1 ends, diode Db_1 conducting, DC power supply Vi, inductance L1, capacitor Cb_1, two
Pole pipe Db_1, inductance L2 and one circuit of booster type capacitive energy storage module composition, diode Db_2, diode Db_1, inductance L2
With another circuit of booster type capacitive energy storage module composition.At this point, Cb_1 charges, the working condition and booster type capacitive energy storage of L2
The working condition of module is related.
(2) when N-type metal-oxide-semiconductor Mb_1 is connected, diode Db_1 cut-off, DC power supply Vi, inductance L1, diode Db_3, N
Type metal-oxide-semiconductor Mb_1, inductance L2 and one circuit of booster type capacitive energy storage module composition, diode Db_2, capacitor Cb_1, diode
Db_3, N-type metal-oxide-semiconductor Mb_1, inductance L2 and another circuit of booster type capacitive energy storage module composition.At this point, Cb_1 discharges, L2's
Working condition is related to the working condition of booster type capacitive energy storage module.
(3) when N-type metal-oxide-semiconductor Ma_1 ends, diode Da_1 conducting, voltage-dropping type capacitive energy storage module, inductance L2, two poles
Pipe Da_1, inductance L3, capacitor Co and load Z constitute a circuit, voltage-dropping type capacitive energy storage module, inductance L2, diode Da_1,
Capacitor Ca_1 and diode Da_2 constitute another circuit.At this point, Ca_1 charges.
(4) when N-type metal-oxide-semiconductor Ma_1 is connected, diode Da_1 cut-off, voltage-dropping type capacitive energy storage module, inductance L2, electronics
Switch Sa and diode Da_2 constitute a circuit, voltage-dropping type capacitive energy storage module, inductance L2, electronic switch Sa, capacitor Ca_1,
Inductance L3, capacitor Co and load Z constitute another circuit.At this point, Ca_1 discharges.
Fig. 6 is simulation work waveform diagram of the embodiment 2 under conditions of θ=0.Fig. 7 is embodiment 2 under conditions of θ=π
Simulation work waveform diagram.By Fig. 6 and Fig. 7 it is found that the input current ii of embodiment 2 is continuous, output electric current ioa is continuous, between grade
Electric current iob is also continuous, and output voltage Vo, which can be greater than, is also smaller than direct current power source voltage Vi, Vo and Vi altogether and same polarity.Comparison
Fig. 6 and Fig. 7 is it is found that there is influence to the ripple of iob in θ.
Content described in this specification embodiment is only enumerating to the way of realization of inventive concept, protection of the invention
Range should not be construed as being limited to the specific forms stated in the embodiments, and protection scope of the present invention is also and in this field skill
Art personnel conceive according to the present invention it is conceivable that equivalent technologies mean.