TWI552494B - High voltage rectifier with double current output - Google Patents

Description

With high frequency switching circuit with double current effect and high step-down ratio rectification Circuit

The invention is a rectifying circuit, in particular to a rectifying circuit with a double current effect and a high step-down ratio with a high frequency switching circuit.

In recent years, due to the rapid development of the electronics industry, a variety of electronic products have gradually played an indispensable role in people's lives, and most of the electronic products required for this use are DC power. However, the power modes produced by the power generation units are all AC power, so the rectifier circuit that converts the AC power generated by the power generation unit into DC power becomes an indispensable part of the electronic products. The rectification circuits commonly used in the market are as follows, for example, a center tap rectification circuit (sixth A picture), a current double circuit (sixth B picture), a synchronous rectification circuit (sixth C picture) or a voltage type half Wave rectifier circuit (fifth D picture), however, the various rectifier circuits described above each have their disadvantages and cannot provide better power quality. For example, refer to Figure 6A. The center-tap rectification circuit is a common high-current rectification circuit. The current of this circuit only needs to pass through one diode, but the transformer and the inductor must withstand the large current source I _o required by the load. And the diode in the circuit must also withstand twice the output voltage V _o , and the ratio of buck at low load to full load is π/2. For another example, referring to FIG. 6B, the current doubler circuit can reduce the current between the inductor and the transformer to be half of the output current I _o , but the inductance of the circuit does not reach the CCM continuous conduction mode (Continuous Conduction Mode). Underneath, it will resonate with the inductance and capacitance of the primary side, thus resulting in a limited power range. For another example, referring to the sixth C, the synchronous rectification circuit is commonly used to increase the output efficiency of the high current circuit, but the control circuit is complicated and the cost of use is greatly increased. For another example, referring to the sixth D diagram, the diode in the half-wave rectifying circuit only needs to withstand twice the input voltage, so the diode with lower cut-in voltage can be selected to reduce the loss of the circuit, but the transformer in the circuit And the inductor must withstand a large current, and the chopping voltage of the circuit rectified output is too high.

The power supply on the market uses a hard switching method. When the power switch is switched, the product of the voltage across the power switch and the current through the power switch will cause switching loss of the power switch, and the switching loss will follow the power switch. The switching frequency is increased and increased, resulting in disadvantages such as reduced overall circuit efficiency, difficulty in heat dissipation, and electromagnetic interference.

In order to solve the disadvantages of the inefficiency of the rectifier circuit and the current use of various types of rectifier circuits, and the loss caused by the power supply of the front stage in the hard switching, the present invention provides a double current effect and high with the high frequency switching circuit. The step-down rectifier circuit comprises an AC rectifier circuit, a high frequency switching circuit, an interleaved half wave rectifier circuit and a three winding transformer. The AC rectification circuit is connected in parallel with an AC power source, and the AC power source is rectified into a DC power source. The DC power output from the AC rectification circuit is input to the high frequency switching circuit, and an AC sine wave is output, and the AC switching circuit outputs the AC. The sine wave is transmitted to the interleaved half-wave rectifying circuit by the three-winding transformer, and the AC sine wave outputs a rectified DC power source to the load via the interleaved half-wave rectifying circuit.

The interleaved half-wave rectifying circuit comprises two sets of half-wave rectifying circuits with different voltage phases, the high-frequency switching circuit is a half-bridge LCC resonant circuit, and the AC rectifying circuit is a bridge full-wave rectifying circuit.

Thereby, the present invention has the following advantages:

1. High voltage gain ratio: The interleaved half-wave circuit 30 is composed of two sets of half-wave rectifying circuits. When the load is full, each set of half-wave rectifying circuits is only turned on for half of the input period, so that the rated working voltage is for each group. The half-wave rectification circuit has an input peak of 1/π, and at no-load, the input capacitance Co is charged to the input peak. Therefore, the interleaved half-wave circuit 30 can provide a step-down ratio of π times.

2. Double current effect: When the rectifying inductor current of one of the half-wave rectifying circuits rises, the rectifying inductor current of the opposite set of half-wave rectifying circuits decreases, and the two rectifying inductor currents After synthesis, the chopping factor of the output current is offset, and the rectifier circuit has a function of double current due to the rectifying inductance and the flywheel effect of the rectifying diode, that is, when a set of half-wave rectifying circuits When the load is supplied to the load through the inductor, the rectifying inductance of the other half-wave rectifying circuit will be continuously discharged by the flywheel diode, so that the transformer only needs to output half of the current and the inductor only needs to withstand one-half of the output current.

3. Low component withstand voltage: In the interleaved half-wave rectification circuit, the diode is subjected to double reverse voltage, so the diode with lower cut-in voltage can be selected to reduce conduction loss and cost.

4. Circuit line loss reduction: The interleaved half-wave rectification circuit makes the two rectified inductor currents I _Lo1 and I _Lo2 one half of the output current I _O compared to other non-interleaved half-wave rectification circuits, such as a center tap rectification circuit. The inductive copper loss of the present invention is reduced by half and the transformer copper loss is 1/4 of the intermediate tap rectifying circuit.

10‧‧‧AC rectifier circuit

11‧‧‧Bridge full-wave rectifier circuit

12‧‧‧Filter capacitor

20‧‧‧High frequency switching circuit

21‧‧‧Half-bridge LCC resonant circuit

211‧‧‧Upper and lower bridge switches

212‧‧‧Resonance circuit

30‧‧‧Interlaced half-wave rectifier circuit

31‧‧‧Half-wave rectifier circuit

40‧‧‧Three winding transformer

50‧‧‧AC power supply

60‧‧‧ load

S ₁ ‧‧‧ switch

S ₂ ‧‧‧ switch

Resonant inductor L _r ‧‧‧

C _r ‧‧‧Resonant series capacitor

C _p ‧‧‧Resonant shunt capacitor

N ₁ ‧‧‧ primary side

N ₂ ‧‧‧ secondary side

N ₃ ‧‧‧ three sides

C _O ‧‧‧ output capacitor

(D _{1 ,} D ₃ ) ‧ ‧ rectifying diode

(D ₂ , D ₄ ) ‧‧‧ flywheel diode

(L _{o1 ,} L _o2 ) ‧ ‧ rectifying inductor

I _o ‧‧‧Output current

The first figure is a block diagram of a circuit in accordance with a preferred embodiment of the present invention.

The second figure is an actual circuit diagram of a preferred embodiment of the present invention.

The third A-D diagram is an action diagram of the working phase of the interleaved half-wave rectifying circuit according to the preferred embodiment of the present invention.

The fourth figure is a current timing diagram of a preferred embodiment of the present invention.

Figure 5 is a current timing diagram of an interleaved half-wave rectification circuit in accordance with a preferred embodiment of the present invention.

The sixth A~D diagram is a schematic diagram of an existing rectifier circuit.

Referring to the first figure, the present invention provides a device with a high frequency switching circuit. The double current effect and the high step-down ratio rectifier circuit include an AC rectifier circuit 10, a high frequency switching circuit 20, an interleaved half wave rectifier circuit 30, and a three winding transformer 40. The AC rectifying circuit 10 is connected to an AC power source 50, and rectifies the AC output of the AC power source 50 into a DC power source. The DC power source is input to the high frequency switching circuit 20 to output an AC sine wave. The high-frequency switching circuit 20 is connected to the AC rectifying circuit 10, which achieves the purpose of raising and lowering by switching the switching operation on/off to meet the requirements of different loads 60. The high frequency switching circuit 20 is connected to the three-winding transformer 40, and the output of the AC sine wave is transmitted to the interleaved half-wave rectifying circuit 30 by the three-winding transformer 40, and the output is output via the interleaved half-wave rectifying circuit 30. The rectified DC power is rectified to the load 60.

Referring to the second figure, the AC rectifying circuit 10 can be a full-wave rectifying circuit, a half-wave rectifying circuit, or can be combined with a power correcting circuit to increase the power factor of the output power source, which is not limited herein. In this embodiment, the AC rectifying circuit 10 is a bridge full-wave rectifying circuit 11 , and the AC power source 50 is connected in parallel with the bridge full-wave rectifying circuit 11 and a filter capacitor 12 , and the AC power provided by the AC power source 50 passes through The DC power supply of the bridge full-wave rectification circuit 11 forms a DC power supply, and the DC power supply reduces the amplitude of the voltage peak change by the filter capacitor 12. The bridge full-wave rectification circuit 11 includes four diodes, corresponding inputs. The alternating sine wave has a relative conduction sequence, so that the output forms the DC power source.

In the embodiment, the high frequency switching circuit 20 is a half bridge type LCC resonant circuit 21, and the bridge full wave rectifying circuit 11 is connected in parallel with the half bridge LCC resonant circuit 21, and the DC power supply is filtered by the filter capacitor 12. The half-bridge LCC resonant circuit 21 is input, wherein the half-bridge LCC resonant circuit 21 includes an upper and a lower bridge switch 211 and a resonant circuit 212. The upper and lower bridge switches 211 are composed of a series of S ₁ and S ₂ switches. The S ₁ and S ₂ switches are all N-channel type metal oxide semiconductor field effect transistors (NMOS FETs), and the series connection manner is that the source of S ₁ is connected to the drain of S ₂ , and in S ₁ and S ₂ A diode is connected in parallel between the source and the source.

The resonant circuit 212 includes a resonant inductor L _r , a resonant series capacitor C _r and a resonant parallel capacitor C _p connected in such a manner that the resonant inductor L _{r is} connected in series with the resonant series capacitor C _{r and} then connected to the resonant parallel capacitor C _p . The resonant inductor L _{r of} the resonant circuit 21 is connected to the source of the S ₁ of the upper and lower bridge switches 211 (or the drain of S ₂ ) to form the resonant circuit 21 , and the resonant circuit 21 may be due to the resonant inductor L _r The resonant series capacitor C _r and the resonant parallel capacitor C _p form an oscillating period.

The upper and lower side switch 211 by control of the S ₁ and S ₂ switch of the interleaved on-time of the input of the DC power into an AC square wave, where, in order to prevent the S ₁ and S ₂ switch are simultaneously turned on and cause a short circuit and, therefore, the switch S ₁ and S ₂ are equipped with the on-time without a switching element interval (dead time), so that S ₁ and S ₂ the switch is turned on was 45%. The DC power source is alternately turned on by the upper and lower bridge switches 211 to form the AC square wave, and the AC square wave is input to the resonant circuit 212 and then synthesized by an oscillation period formed by the resonant circuit 212 to output a boost or a step-down. AC sine wave.

The primary side N _{1 of} the three-winding transformer 40 and the resonant parallel capacitor C _p are connected in parallel, and the secondary side N ₂ and the tertiary side N ₃ are electrically connected to the interleaved half-wave rectifying circuit, so that the AC sine wave can pass through the A three-winding transformer 40 is delivered to the interleaved half-wave rectifier 30.

The interleaved half-wave rectifying circuit 30 can be divided into two sets of half-wave rectifying circuits 31 having different voltage phases, and the half-wave rectifying circuit 31 includes two rectifying diodes (D _{1 ,} D ₃ ) and two flywheel diodes (D). ₂ , D ₄ ), two rectifying inductors (L _{o1 ,} L _o2 ), wherein the secondary side and the third side of the three-winding transformer 40 are electrically connected to the half-wave rectifying circuit 31, respectively, the load 60 and an output capacitor C _{O is} connected in parallel with the interleaved half-wave rectifying circuit 30, and the rectifying inductor (L _o1 /L _o2 ) is charged and supplied with power by a group of half-wave rectifying circuits 31 by the voltages of the three sets of windings around the transformer 40. At the load 60, the other set of rectifying inductors (L _o1 /L _o2 ) are discharged via the corresponding flywheel diode (D ₂ /D ₄ ). The interleaved half-wave rectifying circuit 30 rectifies in a staggered manner, so that the rectified inductor currents (I _Lo1 , I _Lo2 ) flowing through the rectifying inductors (L _o1 , L _o2 ) simultaneously rise at the same time. And falling, after the two rectified inductor currents (I _Lo , I _Lo2 ) are combined, the chopping factor of the output current I _o can be reduced. Wherein, due to the interleaved half-wave rectifying circuit 30, two sets of the half-wave rectifying circuit 31 are used, so that the reverse bias of the diode in the circuit is required to be double the input withstand voltage, so that the cut-in voltage can be selected to be low. The diodes reduce the conduction loss of the diode and reduce the cost of the diode itself.

Referring to the third A~D diagram and the fourth diagram, the third A~D diagram is the interlace The timing diagram of the working phase of the half-wave rectifier circuit 30, the fourth diagram is the timing operation flowchart of the interleaved half-wave rectifier circuit 30, the circuit operation flow of the two figures can be compared with each other, wherein the third A~D diagram and The circuit states of the fourth figure are all considered in steady state.

Referring to FIG third A of (a) and FIG. Phase I of the Fourth, when the working phase I, switch S ₁ is the gate and the source voltage V _gs1 between the electrodes is a high voltage, switch S ₁ is turned on; switch S The electric potential voltage V _gs2 between the gate and source of ₂ is a low potential, and the switch S _{2 is} turned off, so that the switches S ₁ and S _{2 are} switched to zero voltage. The current I _S1 flowing through the switch S ₁ and the current I _r flowing through the resonant inductor L _{r both} rise from a negative half cycle. The AC sine wave outputted by the resonant circuit 212 stores a negative half cycle voltage across the resonant shunt capacitor C _P . At the same time, the negative half-cycle voltage stored by the resonant parallel capacitor C _P is conducted by the primary side N ₁ of the three-winding transformer connected in parallel, and the negative half-cycle voltage causes the rectifier diode D _{1 to be} reverse-cut and rectified. The pole body D _{3 is} turned on, so that the voltage of the primary side N ₁ of the three-winding transformer is conducted to the third side N _{3 of} the three-winding transformer. Wherein, the current I _D3 flowing through the rectifying diode D ₃ is charged to the rectifying inductor L _o2 ; and the half-wave rectifying circuit connected to the secondary side N ₂ circuit of the three-winding transformer is the flywheel The diode D _{2 is} turned on, causing the rectifying inductor L _{o1 to} enter the flywheel state discharge.

Referring to (b) of FIG. 3 and the working phase II of the fourth figure, in the working phase II, the voltage V _gs1 between the gate and the source of the switch S ₁ remains at the same potential as the working phase I, wherein the switches S ₁ I _S1 currents and current of the resonant inductor L _r I _r are positive half cycle from zero to increase the cross conduction type while the half-wave rectifying circuit 30 and the state holding the same session I.

Referring to the third stage B (c) and the fourth stage of the working phase III, during the working phase III, the voltage V _gs1 between the gate and the source of the switches S ₁ , S ₂ remains at the same potential as the working phase I, wherein The current I _S1 flowing through the switch S ₁ and the current I _r flowing through the resonant inductor L _r continue to rise for a positive half cycle.

The AC sine wave outputted by the resonant circuit 212 stores a positive half cycle voltage across the resonant shunt capacitor C _P . At the same time, the positive half-cycle voltage stored by the resonant parallel capacitor C _p is conducted by the primary side N ₁ of the three-winding transformer connected in parallel, and the positive half-cycle voltage causes the rectifying diode D3 to be reverse-cut and the rectification The diode D _{1 is} turned on, so that the voltage of the primary side N ₁ of the three-winding transformer is conducted to the secondary side N _{2 of} the three-winding transformer. Wherein, the current I _D1 flowing through the rectifying diode D ₁ charges the rectifying inductor L _o1 ; and at the same time, the half-wave rectifying circuit connected to the third side N ₃ circuit of the three-winding transformer, the flywheel diode The body D _{4 is} turned on to cause the rectifying inductor L _{o2 to} enter the flywheel state discharge.

Referring to (b) of FIG. B and the working phase IV of the fourth figure, during the working phase IV, the voltage between the gate and the source of the switches S ₁ and S ₂ is due to a conduction time of the non-switching element (dead time) While being turned off at the same time, the current I _r flowing through the resonant rectified power L _r causes the diodes connected in parallel between the S ₂ switch and the source to be turned on, and the interleaved half-wave rectifying circuit 30 is turned on. The state remains the same as session III.

Referring to FIG third C of (e) and a fourth working phase V of FIG, when the working phase V, between the voltage V _GS2 of the switches S ₂ of the gate and source of a high voltage, switch S ₂ is turned on; switch S The voltage V _gs1 between the gate and source of ₁ is a low potential, and the switch S _{1 is} turned off, so that the switches S ₁ and S _{2 are} switched to zero voltage. The current I _S2 flowing through the switch S ₂ rises from the negative half cycle and the current I _{r of the} resonant inductor L _r decreases from the positive half cycle, and the conduction state of the interleaved half-wave rectifying circuit 30 remains the same as the working phase IV.

Referring to (f) of the third C diagram and the working phase VI of the fourth diagram, during the working phase VI, the voltages V _gs1 and V _gs2 between the gate and the source of the switch S ₁ remain at the same potential as the working phase V, wherein The current I _S2 flowing through the switch S ₂ rises from the zero point to the positive half cycle and the current I _{r of the} resonant inductor L _r decreases from the zero point to the negative half cycle. At the same time, the on state of the interleaved half-wave rectifying circuit 30 remains the same as the working phase V.

Referring to (g) of the third D diagram and the working phase VII of the fourth diagram, during the working phase VII, the voltage V _gs1 between the gate and the source of the switches S ₁ , S ₂ remains at the same potential as the working phase VI, wherein The current I _S2 flowing through the switch S ₂ continues to rise from the positive half cycle and the current I _{r of the} resonant inductor L _r continues to decrease from the negative half cycle. The AC sine wave outputted by the resonant circuit 212 stores a negative half cycle voltage for the voltage V _CP across the resonant shunt capacitor C _P . At the same time, the negative half-cycle voltage stored by the resonant parallel capacitor C _P is conducted by the primary side N ₁ of the three-winding transformer connected in parallel, and the negative half-cycle voltage causes the rectifier diode D _{1 to be} reversely turned off. _{3 is} forwarded, so the voltage of the primary side N ₁ of the three-winding transformer is conducted to the third side N _{3 of} the three-winding transformer. Wherein, the current I _D3 flowing through the rectifying diode D ₃ is charged to the rectifying inductor L _o2 ; and at the same time, the half-wave rectifying circuit connected to the primary side N ₁ circuit of the three-winding transformer, the flywheel diode The body D _{2 is} turned on to cause the rectifying inductor L _{o1 to} enter the flywheel state discharge.

Referring to (h) of the third D diagram and the working phase VIII of the fourth diagram, during the working phase VIII, the voltage between the gate and the source of the switches S ₁ and S ₂ is due to a conduction time of the non-switching element (dead time) While being turned off at the same time, the current I _r flowing through the resonant rectified power L _r causes the diodes connected in parallel between the S ₁ switch and the source to be turned on. At the same time, the on state of the interleaved half-wave rectifying circuit 30 remains the same as that of the working phase VII.

In this embodiment, the interleaved half-wave circuit 30 is composed of two sets of half-wave rectifying circuits. Therefore, when the load 60 is fully loaded, each set of half-wave rectifying circuits is only turned on for half of the input period, so that the rated operating voltage is A set of half-wave rectification circuits inputs 1/π of the peak value, and when the load 60 is unloaded, the input capacitance Co is charged to the input peak. Therefore, the interleaved half-wave circuit 30 can provide a step-down ratio of π times.

Referring to the fifth figure, since the two sets of half-wave rectifying circuits of the interleaved half-wave rectifying circuit 30 are respectively staggered, the rectifying inductances (L _o1/ L _o2 ) of one set of half-wave rectifying circuits are charged while the other half is The wave rectifying circuit discharges the rectifying inductor (L _o1/ L _o2 ) into the flywheel state by the flywheel diode. Referring to the first figure, according to Kirchhoff's current law, the output current I _O of the load 60 is the sum of the two rectified inductor currents I _Lo1 and I _Lo2 , and the two rectified inductor currents I _Lo1 and I _Lo2 are the output current I One half of _O , so when the rectifying inductor current of one of the half-wave rectifying circuits rises, the rectifying inductor current of a pair of half-wave rectifying circuits decreases, and the rectifying inductor current is synthesized in the interleaved half-wave rectifying circuit 30. After that, the chopping factor of the output current is offset, and the rectifier circuit has a function of double current due to the rectifying inductance and the flywheel effect of the rectifying diode, that is, when one set of half-wave rectifying circuits supplies power through the inductor, the other The rectifying inductance of the half-wave rectifying circuit will be continuously discharged by the flywheel diode, so the transformer only needs to output half of the current and the inductor only needs to withstand one-half of the output current.

In addition, the function of the double current circuit also reduces the copper loss of the circuit of the interleaved half-wave rectifying circuit 30. Taking the (c) of the third C diagram as an example, the two rectifying inductor currents I _Lo1 , I are known. _Lo2 is one-half of the output current I _O , and the impedances of the rectifying inductors L _O1 and L _O2 are respectively R _L1 and R _L2 , and the impedance values R _L1 and R _L2 are both R _L , as expressed by equation (5); The equivalent impedance of the three sets of winding voltage devices is R _T ; the output current I _O is 20 amps; the transformer loss is P _T and the line loss is P _LO ; the input of the center tap rectifying circuit of the sixth A diagram is set no conversion loss current I _P is equal to a center-tapped inductor current I _L and the three-winding transformer of FIG third D a ~ I 40 of the non-converted _P loss is equal to the rectified inductor current I _Lo1, I _Lo2, wherein the interlaced half-wave The transformer loss of the rectifier circuit 30 is calculated as the following formula (1) and the line loss is calculated as the following formula (2); taking the center tap rectifier circuit of the first diagram as an example, the transformer loss is calculated as the following equation (3) and the line loss is calculated. It is the following formula (4). Comparing the equation (2) with the equation (4), it can be known that the double voltage circuit function of the interleaved half-wave rectifier circuit 30 can reduce the inductance copper loss of the rectifier inductor to one half of the intermediate tap rectifier circuit. Comparing equations (1) and (3), it can be seen that the function of the voltage doubler circuit of the interleaved half-wave rectifier circuit 30 can make the transformer copper loss of the rectifier inductor be 1/4 of the intermediate tap rectifier circuit. Therefore, the effect of the current doubler circuit makes this embodiment suitable for high current devices.

P _T =10 ² R _T =100R _T (1)

P _Lo(1,2) =10 ² R _Lo1 +10 ² R _Lo2 =200R _Lo (2)

P _T =400R _T (three)

P _Lo =20 ² R _Lo =400R _Lo (4)

R _L1 =R _L2 =R _L (five)

Thereby, the embodiment has the following advantages:

1. High voltage gain ratio: The interleaved half-wave circuit 30 is composed of two sets of half-wave rectifying circuits. When the load is full, each set of half-wave rectifying circuits is only turned on for half of the input period, so that the rated working voltage is for each group. The half-wave rectification circuit has an input peak of 1/π, and at no-load, the input capacitance Co is charged to the input peak. Therefore, the interleaved half-wave circuit 30 can provide a step-down ratio of π times.

2. Double current effect: When the rectifying inductor current of one of the half-wave rectifying circuits rises, the rectifying inductor current of the opposite set of half-wave rectifying circuits decreases, and the two rectifying inductor currents After synthesis, the chopping factor of the output current is offset and the current is output due to both rectified inductor currents. Half of them have the function of double current circuit.

3. Low withstand voltage of the component: In the interleaved half-wave rectification circuit, the diode is subjected to double reverse voltage, so the diode with lower cut-in voltage can be selected to reduce the conduction loss and reduce the cost.

4. Circuit line loss reduction: The interleaved half-wave rectification circuit makes the two rectified inductor currents I _Lo1 and I _Lo2 one half of the output current I _O compared to other non-interleaved half-wave rectification circuits, such as a center tap rectification circuit. The inductive copper loss of the present invention is reduced by half and the transformer copper loss is 1/4 of the intermediate tap rectifying circuit.

10‧‧‧AC rectifier circuit

50‧‧‧AC power supply

20‧‧‧High frequency switching circuit

40‧‧‧Three winding transformer

60‧‧‧ load

30‧‧‧Interlaced half-wave rectifier circuit

Claims (2)

A rectifier circuit with a double current effect and a high step-down ratio with a high frequency switching circuit, comprising an AC rectifier circuit, a high frequency switching circuit, an interleaved half wave rectifier circuit and a three winding transformer, wherein: the AC rectification The circuit is connected to an AC power source, and the AC output of the AC power source is rectified into a DC power source; the DC power source outputted by the AC rectifier circuit is input to the high frequency switching circuit to output an AC sine wave; the AC switching circuit outputs the AC The sine wave is transmitted to the interleaved half-wave rectifying circuit by the three-winding transformer, and the high-frequency switching circuit is a half-bridge LCC resonant circuit, and the half-bridge LCC resonant circuit includes an upper and lower bridge switch and a resonant circuit The upper and lower bridge switches are composed of a series of S ₁ and S ₂ switches; and the AC sine wave outputs a rectified DC power supply via the interleaved half-wave rectifying circuit; two separate flows of the interleaved half-wave rectifying circuit The rectified inductor current through the two rectifying inductors simultaneously generates rise and fall at the same time, and after the two rectified inductor currents are combined, the output current can be reduced. a wave factor, and the interleaved half-wave rectifying circuit comprises two sets of half-wave rectifying circuits with different voltage phases, and the two sets of the half-wave rectifying circuits are respectively electrically connected to the secondary side and the third side of the three-winding transformer; The half-wave rectifying circuit is such that one of the conducting diodes and one of the flywheel diodes in the circuit is subjected to a reverse bias voltage of one input withstand voltage, and each of the half-wave rectifying circuits includes a rectifying diode. a flywheel diode and a rectifying inductor, wherein the flywheel diode and the rectifying diode are staggered, and when the alternating chord wave transmitted by the three-winding transformer makes the rectifying diode pass through, the flywheel diode The body is reversely turned off and the rectifying inductor is charged via the rectifying diode; when the AC sine wave transmitted by the three-winding transformer reverses the rectifying diode, the flywheel diode is turned on and the rectifying inductor is passed through The flywheel diode discharges; and the interleaved half-wave rectifier circuit reduces conduction loss of the conduction diode and the flywheel diode. The rectifier circuit with a double current effect and a high step-down ratio according to the first item of the application scope is a bridge full-wave rectifier circuit, and the bridge full-wave rectifier circuit includes four diodes, corresponding inputs. The alternating sine wave has a relative conduction sequence, so that the output forms the DC power source.