A kind of equalizer circuit for converter
Technical field
The present invention relates to a kind of equalizer circuits for converter.
Background technique
Demand with market to large power supply is more and more, many using high input, output voltage currently on the market
Power supply, under high-pressure situations, converter internal component (such as input, output capacitance etc.) voltage stress is increased accordingly.Therefore,
As shown in Figure 1, meeting power source performance requirement frequently with the series and parallel technology of two or more same converter, especially
In order to meet power supply stability (ripple, loop etc.), the electricity of two or more equal capacitance is usually used in input, output end
Hold simultaneously, series connection, the parameter of ideally each converter is consistent, and the input of converter each in this way, output voltage are due to electricity
Hold differential pressure drop as low as N/mono- (N is converter number, N >=2), respective switch voltage stress can equally lower.In Fig. 1 only
Show two it is equal input, output capacitance series connection block diagram, more than two equal capacitance connect block diagram, as long as successively increasing, no longer
It shows.
But in actual circuit, due to being controlled in input, output capacitance inner parameter itself (such as ESR) difference, converter
The discreteness of circuit parameter causes to drive the factors such as pulsewidth is inconsistent, and input, the voltage in output capacitance can be prevented from pressing.It is special
The road Bie Mei parameter differences are very big, and converter works under underloading, it is possible to cause input, the serious voltage un-balance of output capacitance, meeting
So that the components pressure resistance such as capacitor, switching tube, output rectifier diode not enough damages converter.
Drawbacks described above is worth solving.
Summary of the invention
In order to overcome the shortcomings of that existing technology, the present invention provide a kind of equalizer circuit for converter.
Technical solution of the present invention is as described below:
A kind of equalizer circuit for converter, which is characterized in that including transformer and several concatenated output capacitances,
The transformer is equipped with the primary coil of more than two magnetic cores altogether, of the number of the primary coil and the output capacitance
Number is identical, wherein
The Same Name of Ends of n-th primary coil connects N1 inductance, the N1 electricity by the N1 switching tube of unilateal conduction
Feel the anode of other end connection n-th output capacitance;The Same Name of Ends connection N1 power switch tube of the n-th primary coil
Source electrode, the cathode of the drain electrode connection N2 diode of the N1 power switch tube, the anode of the N2 diode connect institute
State the anode of n-th output capacitance;The Same Name of Ends of the n-th primary coil is also connected with the cathode of N4 diode, and described
The anode of N4 diode connects the negative terminal of the n-th output capacitance;
The drain electrode of the different name end connection N2 power switch tube of the n-th primary coil, the N2 power switch tube
Source electrode connect the negative terminal of the n-th output capacitance;The different name end of the n-th primary coil is also connected with N3 diode
Anode, the cathode of the N3 diode connect the anode of the n-th output capacitance.
According to the present invention of above scheme, which is characterized in that the N1 switching tube is diode, the sun of the diode
Pole connects the Same Name of Ends of the n-th primary coil, and cathode connects the N1 inductance.
According to the present invention of above scheme, which is characterized in that the N1 switching tube is power switch tube.
According to the present invention of above scheme, which is characterized in that the number of turns of each primary coil is identical, Same Name of Ends phase
Together.
According to the present invention of above scheme, the beneficial effect is that, the present invention is suitable for high input, output voltage power supply becomes
Converter circuit, enable input during entire transformation, the voltage of output capacitance reaches and presses, equalizing effect is good;Protection electricity
The components such as appearance, switching tube, output rectifier diode will not damage, and whole process controls simple, high reliablity.Circuit of the present invention
It is widely used, while there is isolation effect.
Detailed description of the invention
Fig. 1 is the circuit diagram of converter specific embodiment in the prior art.
Fig. 2 is the circuit diagram of a specific embodiment in the present invention.
Fig. 3 is the current flow diagrams of circuit in Fig. 2.
Specific embodiment
With reference to the accompanying drawing and the present invention is further described in embodiment:
A kind of equalizer circuit for converter, including transformer and several concatenated output capacitances, transformer are equipped with
The primary coil of more than two magnetic cores altogether, the number of primary coil and the number of output capacitance are identical.
As shown in Fig. 2, with two series connection output capacitance (capacitance is equal) voltages of equalizing transform device output end (for input,
The equal output capacitance of output end more than two and series connection, it is similar according to this, no longer illustrate) for carry out principle explanation.Include in figure
One transformer T1, transformer T1 include primary coil T1-A, T1-B of two total magnetic cores, two primary coils T1-A, T1-
B the number of turns is identical, and Same Name of Ends is identical.
Primary coil T1-A and third diode D3, the first power switch tube Q1, the second power switch tube Q2 are connected in series, former
The Same Name of Ends that T1-A is enclosed in sideline connects the source electrode of the first power switch tube Q1, and the anode of third diode D3 is connected to converter the
The anode of five output capacitance C5, the cathode of third diode D3 are connected to the drain electrode of the first power switch tube Q1;Second power is opened
The source electrode for closing pipe Q2 is connected to the midpoint of two capacitor of converter output terminal the 5th output capacitance C5 and the 6th output capacitance C6 (i.e. the
The anode of six output capacitance C6), the different name end of drain electrode connection primary coil T1-A, while the Same Name of Ends of primary coil T1-A connects
Meeting the N1 switching tube DN1 of unilateal conduction, (preferably first diode D1, first diode D1 can also use power switch tube
Substitution.In other embodiments can also using active switch pipe replace, switching tube may include MOSFET pipe, it is silicon-controlled,
IGBT, constant power switching tube semiconductor devices.) anode, the cathode of first diode D1, N1 switching tube DN1 passes through inductance
L1 (this inductance sensibility reciprocal transformation range can be big from 0 to infinity) is connected to the anode of the 5th output capacitance C5 of converter;Primary side line
The Same Name of Ends for enclosing T1-A connects the cathode of the 6th diode D6, and the anode of the 6th diode D6 is connected to the output electricity of output end the 5th
Hold the midpoint of C5 and the 6th output capacitance C6, it is defeated that the different name end of primary coil T1-A by the 5th diode D5 is connected to converter
Anode out.
In a preferred embodiment, the anode of the Same Name of Ends connection first diode D1 of primary coil T1-A, first diode
The cathode of D1 connects inductance L1.
Primary coil T1-B and the 4th diode D4, third power switch tube Q3, the 4th power switch tube Q4 are connected in series, former
The source electrode of the Same Name of Ends connection third power switch tube Q3 of T1-B is enclosed in sideline, and the anode of the 4th diode D4 is connected to converter the
The cathode of the anode of six output capacitance C6, the 4th diode D4 is connected to the drain electrode of third power switch tube Q3;4th power is opened
The source electrode for closing pipe Q4 is connected to the negative terminal of the 6th output capacitance C6 of converter output terminal, and drain electrode connection primary coil T1-B's is different
Name end, while the Same Name of Ends of primary coil T1-B connects the anode of the second diode D2, the cathode of the second diode D2 passes through electricity
Sense L2 is connected to the anode of the 6th output capacitance C6 of converter;The Same Name of Ends of primary coil T1-B connects the yin of the 8th diode D8
Pole, the anode of the 8th diode D8 connect the negative terminal of the 6th output capacitance C6, and the different name end of primary coil T1-B passes through the seven or two
Pole pipe D7 is connected to the midpoint of the 5th output capacitance C5 and the 6th output capacitance C6 of converter output terminal.
As shown in figure 3, structural principle of the invention are as follows:
First power switch tube Q1, the second power switch tube Q2, third power switch tube Q3, the 4th power switch tube Q4 drive
Identical and respective duty ratio is moved less than 50%, when giving a pulse, four power tubes are simultaneously turned on, two series connection outputs
When capacitance voltage is pressed, upper and lower two winding circuits work is consistent, without energy exchange.When two converters input voltage not
When consistent, it is assumed that Vout/2 > VDC2 inputs high pressure all the way due to the presence of the 4th diode D4 according to the law of electromagnetic induction
(T1-A) " dead " is pushed up in the road input voltage Di Na (T1-B) by induced voltage, and the energy for exporting high-voltage end will pass through transformer winding
T1-B and the second diode D2, the second inductance L2 are transmitted to output low-pressure end, current direction as indicated by the arrows in fig. 3, from
And reach equalizing effect.Its correlation rectification with principle of continuity of flow with well known double tube positive exciting topology theory as, do not explain in detail herein
It states.Similarly, if when Vout/2 < VDC2, working principle is same as above.
It should be understood that for those of ordinary skills, it can be modified or changed according to the above description,
And all these modifications and variations should all belong to the protection domain of appended claims of the present invention.
Illustrative description has been carried out to the invention patent above in conjunction with attached drawing, it is clear that the realization of the invention patent not by
The limitation of aforesaid way, if the method concept of the invention patent and the various improvement of technical solution progress are used, or without
It improves and the conception and technical scheme of the invention patent is directly applied into other occasions, be within the scope of the invention.