CN108599591B - Self-current-sharing modularized high-capacity high-boost rectifier - Google Patents

Abstract

The invention proposes a self-equalizing modularized large-capacity high-boost rectifier. In the traditional large-capacity and high-boost rectification occasions, multiple rectification modules are often required to operate in parallel and the transformer is boosted. There are problems such as uneven power distribution among multiple modules, poor system reliability, and high cost. Therefore, the present invention proposes a Large-capacity, modular, high-gain rectifier with automatic current sharing and adjustable rectified output voltage gain. The proposed converter contains m (must be an even number), the first module is composed of n-1 capacitors and diodes, and the other modules are composed of n capacitors and diodes. Compared with the existing scheme, the number of modules can be It can be adjusted freely, and each module can automatically share the current, which is more suitable for large-capacity and high-gain rectification occasions that require electrical isolation.

Description

A self-sharing modular large-capacity high-boost rectifier

technical field

The invention relates to a large-capacity, high-boost non-isolated rectifier, in particular to a self-equalizing modularized large-capacity high-boost rectifier.

Background technique

The traditional voltage doubler rectifier circuit, on the one hand, can achieve a higher voltage output, but generally only the input and output gains are adjustable, and the current stress of the device is high and cannot be adjusted, so it is difficult to select the device in large-capacity applications. On the other hand, It is often necessary to run multiple rectifier modules in parallel to increase its capacity, and there are problems such as uneven power distribution among multiple modules, poor system reliability, and difficulty in current sharing.

Contents of the invention

In order to solve the shortcomings of existing rectifiers in large-capacity and high-boost applications, the present invention proposes a large-capacity non-isolated rectifier that can automatically share current, has high voltage gain and can be adjusted.

The present invention adopts following technical scheme:

A self-sharing modular large-capacity high-boost rectifier, the converter includes an AC input source, m (must be an even number) modules, an output diode D ₀ , a filter capacitor C ₀ , and a load R _L ;

Among them, m modules include:

Module one includes diodes D ₁₂ , D _{13 ...} D _1n , capacitors C ₁₂ , C _{13 ...} C _1n . The other end of capacitor C ₁₂ , C _13... C _1n is connected, and then connected with one end of the power supply, and at the same time connected with the anode of diode D ₂₁ and the other end of filter capacitor C ₀ and load _RL , and the cathode of diode D ₁₂ It is connected to one end of the capacitor _C12 , the cathode of the diode _D13 is connected to one end of the capacitor _C13 , ..., and so on, the cathode of the diode _D1n is connected to one end of the capacitor _C1n .

The second module includes diodes D ₂₁ , D _{22 ...} D _2n , capacitors C ₂₁ , C _{22 ...} C _2n . The other end of capacitor C ₂₁ , C _22... C _2n is connected, and then connected with the other end of the power supply, the cathode of diode D ₂₁ is connected with one end of capacitor C ₂₁ , and the cathode of diode D ₂₂ is connected with one end of capacitor C ₂₂ , ..., and so on, the cathode of the diode D _2n is connected to one end of the capacitor C _2n .

Module three includes diodes D ₃₁ , D _{32 ...} D _3n , capacitors C ₃₁ , C _{32 ...} C _3n . The other ends of capacitors C ₃₁ and C _32... C _3n are connected together, and then connected together with one end of the power supply, the cathode of diode D ₃₁ is connected with one end of capacitor C ₃₁ , the cathode of diode D ₃₂ is connected with one end of capacitor C ₃₂ , ..., and so on, the cathode of the diode D _3n is connected to one end of the capacitor C _3n .

...

By analogy, the module m-1 includes diodes D _m-11 , D _m-12··· D _m-1n , capacitors C _m-11 , C _m-12··· C _m-1n . The other ends of the capacitors C _m-11 and C _m-12··· C _m-1n are connected, and then connected with one end of the power supply, the cathode of the diode D _m-11 is connected with one end of the capacitor C _m-11 , and the diode D _m The cathode of _-12 is connected to one end of the capacitor C _m-12, . . . and so on, the cathode of the diode D _m-1n is connected to one end of the capacitor C _m-1n .

The module m includes diodes D _m1 , D _{m2 ...} D _mn , capacitors C _m1 , C _{m2 ...} C _mn . The other ends of capacitors C _m1 and C _m2 are connected to the other end of C _mn , and then connected to the other end of the power _supply . The cathode of diode D _m1 is connected to one end of capacitor C m1, and the cathode of diode D _m2 is connected to one end of capacitor C _m2 . Connected, ..., and so on, the cathode of the diode D _mn is connected to one end of the capacitor C _mn . The node between the cathode of diode _Dmn and one end of capacitor _Cmn is connected to the anode of diode _D0 .

The connection relationship between modules and modules and between power supplies and modules is:

The node between the other end of capacitor C ₁₂ and one end of the power supply in the first module is connected to the anode of diode D ₂₁ in the second module, and the node between the cathode of diode D ₁₂ and one end of C ₁₂ in the first module is connected to the module The anode of the diode D ₂₂ in the second module, the node between the cathode of the diode D ₁₃ in the first module and one end of C ₁₃ is connected to the anode of the diode D ₂₃ in the second module, ..., and so on, the diode D in the first module The node between the cathode of _1n and one end of capacitor C _1n is connected to the anode of diode D _2n in module 2.

The node between the cathode of diode D ₂₁ and one end of C ₂₁ in the second module is connected to the anode of diode D ₃₁ in module three, and the node between the cathode of diode D ₂₂ and one end of C ₂₂ in the second module is connected to diode D in module three ₃₂ anodes, ..., and so on, the node between the cathode of diode D _2n and one end of C _2n in the second module is connected to the anode of diode D _3n in module three.

By analogy, the node between the cathode of the diode D _m-11 in the m-1th module and one end of the capacitor C _{m-11 is} connected to the anode of the diode D _m1 in the module m, and the diode D _m-12 in the m-1th module The node between the cathode and one end of the capacitor C _m-12 is connected to the anode of the diode D _m2 in the module m, ..., and so on, the cathode of the diode D _m-1n in the m-1th module is connected to the capacitor C _m-1n The node between one end is connected to the anode of diode _Dmn in module m.

The node between the cathode of diode D _m1 and one end of capacitor C _m1 in the mth module is connected to the anode of diode _D12 in module one, and the node between the cathode of diode D _m2 and one end of capacitor C _m2 in the mth module is connected to module one The anode of diode _{D 13 , .}

The load _RL is connected in parallel with C ₀ , one end of the load _RL is connected to the cathode of the diode D ₀ , and the other end is connected to the node between the other end of the capacitor C ₁₂ in module 1 and one end of the power supply. The anode of diode _D0 is connected to the node between the cathode of diode _Dmn and one end of capacitor _Cmn . An even number of modules is connected to the other end of the power supply, and an odd number of modules is connected to one end of the power supply.

The present invention is a self-equalizing modularized large-capacity high-boost rectifier, and the technical effects are as follows:

1. The input and output gain is high and adjustable, and the voltage and current stress of the switching device is low and adjustable. in:

The ratio of the output voltage to the input voltage is:

The voltage stress of the diode is:

m is the number of input phases, n is the number of diodes and capacitors in the module.

2. Each module can realize automatic current sharing, and the power of the transformer is shared equally.

3. Save the large power frequency transformer, reduce the system size and cost.

Description of drawings

Fig. 1 is the general diagram of circuit principle of the present invention.

Fig. 2 is a circuit topology diagram of the present invention where m=4 and n=2.

Fig. 3 is a waveform diagram of the input and output voltages of the present invention.

Fig. 4 is a voltage waveform diagram of diodes D ₂₁ , D ₃₁ , D ₄₁ and D ₁₂ of the present invention.

Fig. 5 is a current waveform diagram of diodes D ₂₁ , D ₃₁ , D ₄₁ and D ₁₂ of the present invention.

FIG. 6 is a voltage waveform diagram of capacitors C ₂₁ -C ₄₂ in the present invention.

Fig. 7 is a simulation waveform diagram of four module currents of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

As shown in Figure 2, a self-sharing modular large-capacity high-boost rectifier includes an AC input source, 4 modules, and 8 capacitors C ₀ , C ₂₁ , C ₃₁ , C ₄₁ , C ₁₂ , C ₂₂ , C ₃₂ , C ₄₂ , 8 diodes D ₀ , D ₂₁ , D ₃₁ , D ₄₁ , D ₁₂ , D ₂₂ , D ₃₂ , D ₄₂ , and one load _RL . in:

Of the 4 modules:

Module one includes a diode D ₁₂ and a capacitor C ₁₂ . The other end of the capacitor _C12 is connected to one end of the power supply, and is connected to the anode of the diode _D21 , the other end of the filter capacitor _C0 and the load R _L , and the cathode of the diode _D12 is connected to one end of the capacitor _C12 .

Module two includes diodes D ₂₁ , D ₂₂ , and capacitors C ₂₁ , C ₂₂ . The other ends of the capacitors C ₂₁ and C ₂₂ are connected together, and then connected with the other end of the power supply. The cathode of the diode D ₂₁ is connected to one end of the capacitor C 21 , and the cathode of the diode _{D 22 is} connected to one end of the capacitor C ₂₂ .

Module three includes diodes D ₃₁ , D ₃₂ , and capacitors C ₃₁ , C ₃₂ . The other ends of the capacitors C ₃₁ and C ₃₂ are connected together and then connected to one end of the power supply, the cathode of the diode D ₃₁ is connected to one end of the capacitor C ₃₁ , and the cathode of the diode D ₃₂ is connected to one end of the capacitor C ₃₂ .

Module four includes diodes D ₄₁ , D ₄₂ , and capacitors C ₄₁ , C ₄₂ . The other ends of the capacitors C ₄₁ and C ₄₂ are connected together, and then connected together with one end of the power supply, the cathode of the diode D ₄₁ is connected with one end of the capacitor C ₄₁ , and the cathode of the diode D ₄₂ is connected with one end of the capacitor C ₄₂ . The node between the cathode of diode D ₄₂ and one end of capacitor C ₄₂ is connected to the anode of diode D ₀ .

The connection relationship between modules and modules and between power supplies and modules is:

The node between the other end of capacitor C ₁₂ and one end of the power supply in the first module is connected to the anode of diode D ₂₁ in the second module, and the node between the cathode of diode D ₁₂ and one end of C ₁₂ in the first module is connected to the module The anode of the second diode D ₂₂ ,

The node between the cathode of diode D ₂₁ and one end of C ₂₁ in the second module is connected to the anode of diode D ₃₁ in module three, and the node between the cathode of diode D ₂₂ and one end of C ₂₂ in the second module is connected to diode D in module three ₃₂ anodes.

The node between the cathode of diode D ₃₁ and one end of capacitor C ₃₁ in the third module is connected to the anode of diode D ₄₁ in module four, and the node between the cathode of diode D ₃₂ and one end of capacitor C ₃₂ in the third module is connected to module four Anode of diode D ₄₂ .

The node between the cathode of the diode D ₄₁ in the fourth module and one end of the capacitor C ₄₁ is connected to the anode of the diode D ₁₂ in the first module.

The load _RL is connected in parallel with C ₀ , one end of the load _RL is connected to the cathode of the diode D ₀ , and the other end is connected to the node between the other end of the capacitor C ₁₂ in module 1 and one end of the power supply. The anode of diode _D0 is connected to the node between the cathode of diode _D42 and one end of capacitor _C42 . Module 1 and module 3 are connected to one end of the power supply, and modules 2 and 4 are connected to one end of the power supply.

According to the different direction of AC power current, the circuit can be divided into two working states:

(1) When the input alternating current is on the positive half axis. The input current charges the capacitor C ₂₁ through the diode D ₂₁ , charges the capacitor C ₂₂ through the diode D ₂₂ , and discharges the capacitor C ₁₂ ; at the same time, the input current charges the capacitor C ₄₁ through the diode D ₄₁ , discharges the capacitor C ₃₁ , and discharges the capacitor C 12 through the diode D ₄₂ . The capacitor C ₄₂ is charged, and the capacitor C ₃₂ is discharged; at this moment, the diodes D ₃₂ , D ₁₂ , D ₃₂ , and D ₀ are all turned off.

(2) When the input alternating current is in the negative half-axis, the input current passes through the diode D ₂₃₁ to charge the capacitor C ₃₁ , the capacitor C ₂₁ discharges, charges the capacitor C ₃₂ through the diode D ₃₂ , and discharges the capacitor C ₂₂ ; at the same time, the input current passes through Diode D ₁₂ charges capacitor C ₁₂ , discharges capacitor C ₄₁ , charges capacitor C ₀ through diode D ₀ , discharges capacitor C ₄₂ , and supplies power to load R _L at the same time; at this time, diodes D ₂₁ , D ₄₁ , D ₂₂ , and D ₄₂ are all turned off.

Analysis of the principle of automatic current sharing:

Take the four modules in Figure 2 as an example. When the input alternating current is in the positive semi-axis, all the diodes are turned off, the capacitors C ₃₁ , C ₁₂ , and C ₃₂ are discharged, and the capacitors C ₂₁ , C ₄₁ , C ₂₂ , and C ₄₂ are charged, and the voltage drop of Uin is much faster than the drop of the capacitor voltage speed. The input voltage Uin starts to rise from 0, when Uin rises to be greater than the voltage U _C21 of the capacitor C ₂₁ , the diode D ₂₁ conducts, the capacitor C ₂₁ begins to charge, and the voltage rises; when Uin rises to (Uin+U _C12 ) greater than U _C22 At this time, the diode D ₂₂ is turned on, the capacitor C ₂₂ starts to charge, and the voltage rises. At the same time, when Uin rises to (Uin+U _C31 ) greater than U _C41 , diode D ₄₁ conducts, capacitor C ₄₁ begins to charge, the voltage rises, and when Uin rises to (Uin+U _C32 ) greater than U _C42 , diode D ₄₂ conducts , the capacitor C ₄₂ starts charging, and the voltage rises. Capacitors C ₂₁ , C ₄₁ , C ₂₂ , and C ₄₂ continue to charge until Uin rises to the maximum value Uin _max . At the next moment, diodes D ₂₁ , D ₄₁ , D ₂₂ , and D ₄₂ are reversely cut off. Capacitors C ₂₁ , C ₄₁ , C ₂₂ and C ₄₂ are fully charged, and capacitors C ₃₁ , C ₁₂ and C ₃₂ are fully discharged. It is similar when the input alternating current is on the negative semi-axis, and will not be repeated here.

According to the capacitance C _o ampere-second balance principle, the output current I _o is equal to the current I _D0 flowing through the diode D ₀ , due to the existence of the capacitor C ₄₂ , the current _ID42 flowing through the diode D ₄₂ is equal to I _D0 , and so on, the first In one branch, the current I _D21 flowing through the diode D ₁ is equal to the output current I _o . Similarly, the currents flowing through other branches are also equal to the output current I _o , and the present invention realizes automatic current sharing. The analysis process extended to n modules is similar.

Through the above analysis, it can be seen that the converter saves the transformer, realizes automatic current sharing, and the modular design greatly increases the capacity of the converter.

Simulation parameters: switching frequency f = 50Hz, input voltage u _in is 30V, output voltage u _o is close to 240V, power P = 115.2W. It can be seen from the figure that the currents of the four modules are equal, realizing automatic current sharing of each module.

Claims (1)

1. A self-balanced modular large-capacity high-boost rectifier, characterized in that: the rectifier includes an AC input source, m modules, m is an even number, output diode D ₀ , filter capacitor C ₀ , load R _L ; Among them, m modules include: Module 1 includes diodes D ₁₂ , D ₁₃ ···D _1n , capacitors C ₁₂ , C ₁₃ ···C _1n ; the other ends of capacitors C ₁₂ , C ₁₃ ···C _1n are connected, and then connected to one end of the power supply , while connected to the anode of diode D ₂₁ and the other end of filter capacitor C ₀ and load _RL , the cathode of diode D ₁₂ is connected to one end of capacitor C ₁₂ , the cathode of diode D ₁₃ is connected to one end of capacitor C ₁₃ , .. ., and so on, the cathode of the diode D _1n is connected to one end of the capacitor C _1n ; Module 2 includes diodes D ₂₁ , D ₂₂ ··· D _2n , capacitors C ₂₁ , C ₂₂ ···C _2n ; the other ends of capacitors C ₂₁ , C ₂₂ ···C _2n are connected, and then connected to the other end of the power supply at Together, the cathode of diode D ₂₁ is connected to one end of capacitor C ₂₁ , the cathode of diode D ₂₂ is connected to one end of capacitor C ₂₂ , ..., and so on, the cathode of diode D _2n is connected to one end of capacitor C _2n ; module three Including diodes D ₃₁ , D ₃₂ ···D _3n , capacitors C ₃₁ , C ₃₂ ···C _3n ; the other ends of capacitors C ₃₁ , C ₃₂ ···C _3n are connected to one end of the power supply, and the diode The cathode of D ₃₁ is connected to one end of capacitor C ₃₁ , the cathode of diode D ₃₂ is connected to one end of capacitor C ₃₂ , ..., and so on, the cathode of diode D _3n is connected to one end of capacitor C _3n ; ... By analogy, module m-1 includes diodes D _m-11 , D _m-12 ... D _m-1n , capacitors C _m-11 , C _m-12 ... C _m-1n ; capacitor C _m-11 , C _m-12 ···The other end of C _m-1n is connected, and then connected with one end of the power supply, the cathode of diode D _m-11 is connected with one end of capacitor C _m-11 , and the cathode of diode D _m-12 is connected with One end of the capacitor C _m-12 is connected, ..., and so on, the cathode of the diode D _m-1n is connected to one end of the capacitor C _m-1n ; Module m includes diodes D _m1 , D _m2 ··· D _mn , capacitors C _m1 , C _m2 ···C _mn ; the other ends of capacitors C _m1 , C _m2 ···C _mn are connected, and then connected to the other end of the power supply Together, the cathode of the diode D _m1 is connected to one end of the capacitor C _m1 , the cathode of the diode D _m2 is connected to one end of the capacitor C _m2 , ..., and so on, the cathode of the diode D _mn is connected to one end of the capacitor C _mn ; the diode The node between the cathode of D _mn and one end of capacitor C _mn is connected to the anode of diode D ₀ ; The connection relationship between modules and modules and between power supplies and modules is: The node between the other end of capacitor C ₁₂ and one end of the power supply in the first module is connected to the anode of diode D ₂₁ in the second module, and the node between the cathode of diode D ₁₂ and one end of C ₁₂ in the first module is connected to the module The anode of the diode D ₂₂ in the second module, the node between the cathode of the diode D ₁₃ in the first module and one end of C ₁₃ is connected to the anode of the diode D ₂₃ in the second module, ..., and so on, the diode D in the first module The node between the cathode of _1n and one end of capacitor C _1n is connected to the anode of diode D _2n in module 2; The node between the cathode of diode D ₂₁ and one end of C ₂₁ in the second module is connected to the anode of diode D ₃₁ in module three, and the node between the cathode of diode D ₂₂ and one end of C ₂₂ in the second module is connected to diode D in module three ₃₂ anodes, ..., and so on, the node between the cathode of diode D _2n and one end of C _2n in the second module is connected to the anode of diode D _3n in module three; By analogy, the node between the cathode of the diode D _m-11 in the m-1th module and one end of the capacitor C _{m-11 is} connected to the anode of the diode D _m1 in the module m, and the diode D _m-12 in the m-1th module The node between the cathode and one end of the capacitor C _m-12 is connected to the anode of the diode D _m2 in the module m, ..., and so on, the cathode of the diode D _m-1n in the m-1th module is connected to the capacitor C _m-1n The node between one end is connected to the anode of diode _Dmn in module m; The node between the cathode of diode D _m1 and one end of capacitor C _m1 in the mth module is connected to the anode of diode _D12 in module one, and the node between the cathode of diode D _m2 and one end of capacitor C _m2 in the mth module is connected to module one The anode of the diode D ₁₃ , ..., and so on, the node between the cathode of the diode D _mn-1 in the mth module and one end of the capacitor C _mn-1 is connected to the anode of the diode D _1n in the module one; The load _RL is connected in parallel with C ₀ , one end of the load _RL is connected to the cathode of the diode D ₀ , and the other end is connected to the node between the other end of the capacitor C ₁₂ in module 1 and one end of the power supply; the anode of the diode D ₀ is connected to the cathode of the diode D _mn It is connected to the node between one end of the capacitor C _mn ; the even number of modules is connected to the other end of the power supply, and the odd number of modules is connected to one end of the power supply; When m=4, n=2, according to the different directions of the AC power supply current, the circuit is divided into two working states: (1) When the input alternating current is on the positive half axis: The input current charges the capacitor C21 through the diode D21, charges the capacitor C22 through the diode D22, and discharges the capacitor C12; at the same time, the input current charges the capacitor C41 through the diode D41, discharges the capacitor C31, charges the capacitor C42 through the diode D42, and discharges the capacitor C32; Diodes D31, D12, D32, and D0 are all turned off; (2) When the input alternating current is on the negative half axis: The input current charges the capacitor C31 through the diode D31, discharges the capacitor C21, charges the capacitor C32 through the diode D32, and discharges the capacitor C22; at the same time, the input current charges the capacitor C12 through the diode D12, discharges the capacitor C41, and charges the capacitor C0 through the diode D0 , the capacitor C42 discharges, and supplies power to the load RL at the same time; at this time, the diodes D21, D41, D22, and D42 are all turned off.