CN214412377U

CN214412377U - Three-level topology charging structure compatible with single-phase and three-phase alternating-current input

Info

Publication number: CN214412377U
Application number: CN202120555293.5U
Authority: CN
Inventors: 李微; 林木松
Original assignee: Pluckystone Technologies Co ltd
Current assignee: Pluckystone Technologies Co ltd
Priority date: 2021-03-18
Filing date: 2021-03-18
Publication date: 2021-10-15
Anticipated expiration: 2031-03-18

Abstract

A three-level topology charging structure compatible with single-phase and three-phase alternating-current input is characterized by comprising a first input terminal, a second input terminal, a third input terminal, a fourth input terminal, a three-phase PFC converter, a DC-DC isolation converter, a DC-DC non-isolation converter, a first switch S1 and a second switch S2, wherein the input end of the three-phase PFC converter is connected with the first input terminal, the second input terminal and the third input terminal; the input end of the DC-DC isolation converter is connected with the output end of the three-phase PFC converter; the input end of the DC-DC non-isolated converter is connected with the output end of the DC-DC isolated converter and is used for outputting high-precision direct current; the first switch S1 is connected between the first input terminal and the second input terminal; the second switch S2 is connected between the three-phase PFC converter and the fourth input terminal; when the first switch S1 and the second switch S2 are open, the charging structure is suitable for three-phase ac input; when the first switch S1 and the second switch S2 are closed, the charging structure is adapted for unidirectional ac input.

Description

Three-level topology charging structure compatible with single-phase and three-phase alternating-current input

[ technical field ] A method for producing a semiconductor device

The utility model relates to a machine charges, in particular to compatible single-phase and three-phase AC input's tertiary topology charging structure.

[ background of the invention ]

Charging equipment of an electric vehicle is mainly classified into a vehicle-mounted type and a non-vehicle-mounted type according to places. The non-vehicle-mounted type mainly comprises charging equipment fixed outside the vehicle. The vehicle-mounted device is a device which is fixed in the vehicle and can be charged along with the vehicle. Compared with non-vehicle charging equipment, the vehicle-mounted charger is more convenient and more popular, so that the application prospect is wider. However, the vehicle-mounted charger belongs to a slow charging mode, generally needs 10-12 hours, so that most vehicle owners mostly choose to charge at night and other times with low time requirements. As battery endurance further increases, the requirements for charging time become more stringent. The conventional single-phase input power no longer meets the requirement of charging time, so that the research on the three-phase input of higher power level is very necessary. Meanwhile, most of the current household alternating current interfaces are single-phase alternating current interfaces, which means that the traditional charging mode of single-phase alternating current input has larger market application. The demand of the vehicle-mounted charger capable of working under two working conditions of single phase and three phase is getting bigger and bigger, so that the research on the charger capable of carrying out single-phase and three-phase input is of great significance.

In addition, the charging structure of the existing charger is usually a two-stage topology, which can better achieve the purposes of wide output range, small ripple and light grid pollution, but does not achieve the utmost point yet, and still has an improvement space.

[ Utility model ] content

The utility model aims at solving the above problem, and provide a compatible single-phase and three-phase AC input's tertiary topology charging structure.

In order to solve the above problem, the utility model provides a compatible single-phase and three-phase ac input' S tertiary topology charging structure, its characterized in that, it includes first input terminal, second input terminal, third input terminal, fourth input terminal, three-phase PFC converter, DC-DC isolating converter, DC-DC non-isolating converter, first switch S1 and second switch S2, the input of three-phase PFC converter with first input terminal, second input terminal, third input terminal are connected; the input end of the DC-DC isolation converter is connected with the output end of the three-phase PFC converter; the input end of the DC-DC non-isolated converter is connected with the output end of the DC-DC isolated converter and is used for outputting high-precision direct current; the first switch S1 is connected between the first input terminal and the second input terminal; the second switch S2 is connected between the three-phase PFC converter and a fourth input terminal; when the first switch S1 and the second switch S2 are open, the charging structure is adapted for three-phase ac input; when the first switch S1 and the second switch S2 are closed, the charging structure is suitable for unidirectional ac input.

Further, the three-phase PFC converter is a three-phase six-switch PFC converter, and when the first switch S1 and the second switch S2 are closed, the front stage of the charging structure is converted into a two-phase staggered parallel totem-pole PFC converter.

Further, the DC-DC isolation converter is a phase-shifted full-bridge circuit with zero-voltage switching-on.

Further, the DC-DC non-isolated converter is a Buck-Boost type topological converter.

Further, an RCD absorption circuit is arranged at the output end of the DC-DC isolation converter.

Further, the three-phase PFC converter comprises inductors L1, L2, L3, a switch tube Q1, Q2, Q3, Q4, Q5, Q6 and a capacitor C1, wherein a first end of the inductor L1 is connected with the first input terminal, and a second end of the inductor L1 is connected with a source electrode of the switch tube Q1 and a drain electrode of the switch tube Q4; a first end of the inductor L2 is connected to the second input terminal, and a second end of the inductor L2 is connected to a source of the switching tube Q3 and a drain of the switching tube Q6; a first end of the inductor L3 is connected to the third input terminal, and a second end of the inductor L3 is connected to the source of the switching tube Q5 and the drain of the switching tube Q2; the drains of the switching tubes Q1, Q3 and Q5 are respectively connected with the first end of the capacitor C1, and the sources of the switching tubes Q4, Q2 and Q6 are respectively connected with the second end of the capacitor C1.

Further, the first switch S1 is connected between the first end of the inductor L1 and the first end of the inductor L2, and the second switch S2 is connected between the second end of the inductor L3 and the fourth input terminal.

Further, the DC-DC isolation converter includes switching tubes Q7, Q8, Q9, Q10, inductors L4, L5, transformer T1, diodes D1, D2, D3, D4, and a capacitor C2, wherein drains of the switching tubes Q7, Q8 are connected to a first end of the capacitor C1, and sources of the switching tubes Q9, Q10 are connected to a second end of the capacitor C1; the source of the switching tube Q7 and the drain of the switching tube Q9 are connected with one end of the primary coil of the transformer T1 through the inductor L4, and the source of the switching tube Q8 and the drain of the switching tube Q10 are connected with the other end of the primary coil of the transformer T1; one end of a secondary winding of the transformer T1 is connected with the anode of the diode D1 and the cathode of the diode D3, and the other end of the secondary winding is connected with the anode of the diode D2 and the cathode of the diode D4; cathodes of the diodes D1 and D2 are connected to a first end of the inductor L5, and a second end of the inductor L5 is connected to a first end of the capacitor C2; the anodes of the diodes D3 and D4 are connected to the second terminal of the capacitor C2.

Further, the RCD absorption circuit includes a resistor R1, a capacitor C3, and a diode D5, wherein an anode of the diode D5 is connected to the first end of the inductor L5, a cathode of the diode D5 is connected to a common connection end of the capacitor C3 and the resistor R1, another end of the capacitor C3 is connected to the second end of the capacitor C2, and another end of the resistor R1 is connected to the second end of the inductor L5.

Further, the DC-DC non-isolated converter includes a switch Q11, a diode D6, an inductor L6, and a capacitor C4, a drain of the switch Q11 is connected to a first end of the capacitor C2, a source of the switch Q11 is connected to a first end of the inductor L6 and a cathode of the diode D6, a second end of the inductor L6 is connected to a second end of the capacitor C2, an anode of the diode D6 is connected to the first end of the capacitor C4, and the second end of the capacitor C4 is connected to the second end of the inductor L6.

The beneficial contributions of the utility model reside in that, it has effectively solved above-mentioned problem. The utility model discloses a compatible single-phase and three-phase AC input' S tertiary topology charging structure is equipped with 4 binding post and switchable PFC converter, and when first switch S1 and second switch S2 disconnection, the PFC converter of front level is six switch three-phase PFC converters, and it is applicable to three-phase AC input; when the second switch S2 and the second switch S2 are closed, the pre-stage PFC converter is converted into a two-phase staggered parallel totem-pole PFC converter, which is suitable for single-phase alternating-current input. By controlling the on-off of the first switch S1 and the second switch S2, the single-phase and three-phase alternating current input can be compatible, and the application range is expanded. Furthermore, the utility model discloses a charge structure is tertiary topology, and it has designed DC-DC non-isolation converter behind second level DC-DC isolation converter, and it can be to the electric energy quality of second level circuit output secondary regulation and guarantee to output wide range adjustable, low output ripple, the controlled high-quality direct current of precision.

[ description of the drawings ]

Fig. 1 is a schematic block diagram of the present invention.

Fig. 2 is a circuit structure of the present invention.

[ detailed description ] embodiments

The following examples are further to explain and supplement the present invention, and do not constitute any limitation to the present invention.

As shown in fig. 1 and fig. 2, the main point of the three-level topology charging structure compatible with single-phase and three-phase ac input of the present invention is that the PFC converter at the front stage can be switched by turning on and off the first switch S1 and the second switch S2, and when the first switch S1 and the second switch S2 are turned off, the PFC converter at the front stage is a three-phase six-switch PFC converter, which is suitable for three-phase ac input; when the second switch S2 and the second switch S2 are closed, the pre-stage PFC converter is converted into a two-phase staggered parallel totem-pole PFC converter, which is suitable for single-phase alternating-current input. By controlling the on-off of the first switch S1 and the second switch S2, the single-phase and three-phase alternating current input can be compatible, and the application range is expanded.

As shown in fig. 1 and fig. 2, the present invention is compatible with single-phase and three-phase ac input three-level topology charging structure, which includes a first input terminal, a second input terminal, a third input terminal, a fourth input terminal, a three-phase PFC converter, a DC-DC isolated converter, a DC-DC non-isolated converter, a first switch S1 and a second switch S2. The first input terminal, the second input terminal, the third input terminal and the fourth input terminal are respectively used for connecting three phase lines 1, 2 and 3 of three-phase alternating current and a neutral line N. The three-phase PFC converter is a first-stage topology, can finish power factor correction under certain input voltage waveform, provides stable and reliable intermediate-stage direct current input for a second-stage circuit, and prevents current of a charger from polluting a power grid. The DC-DC isolation converter is a second-stage topology and is used for outputting direct-current voltage in a specific range, and meanwhile, the DC-DC isolation converter plays a role in isolating a power grid and charging equipment so as to guarantee daily use safety. The DC-DC non-isolated converter is a third-stage topology and is used for performing secondary regulation and guarantee on the quality of electric energy output by the second-stage circuit so as to output high-quality direct current with adjustable wide range, low output ripple and controlled precision. The first switch S1 and the second switch S2 are used to switch a first stage topology that is a three-phase PFC converter adapted for three-phase ac input when both the first switch S1 and the second switch S2 are open. When the first switch S1 and the second switch S2 are closed, the three-phase PFC converter of the first-stage topology can be converted into a two-phase staggered parallel totem-pole PFC converter suitable for single-phase alternating-current input, so that the single-phase alternating-current input is compatible.

In this embodiment, as shown in fig. 2, the three-phase PFC converter includes inductors L1, L2, and L3, switching tubes Q1, Q2, Q3, Q4, Q5, and Q6, and a capacitor C1.

A first end of the inductor L1 is connected to the first input terminal, and a second end of the inductor L1 is connected to the source of the switching transistor Q1 and the drain of the switching transistor Q4.

A first end of the inductor L2 is connected to the second input terminal, and a second end of the inductor L2 is connected to the source of the switching transistor Q3 and the drain of the switching transistor Q6.

A first end of the inductor L3 is connected to the third input terminal, and a second end of the inductor L3 is connected to the source of the switching transistor Q5 and the drain of the switching transistor Q2.

The drains of the switching tubes Q1, Q3 and Q5 are respectively connected with the first end of the capacitor C1, and the sources of the switching tubes Q4, Q2 and Q6 are respectively connected with the second end of the capacitor C1, so as to output direct current to the second-stage topology.

The first switch S1 and the second switch S2 are relays, wherein the first switch S1 is connected between the first end of the inductor L1 and the first end of the inductor L2, and between the first input terminal and the second input terminal. The second switch S2 is connected between the second end of the inductor L3 and the fourth input terminal.

When the first switch S1 and the second switch S2 are open, they are three-phase ac input, and the first-stage topology is a three-phase six-switch PFC converter, and the operation principle can refer to the known technology.

When the first switch S1 and the second switch S2 are closed, the first input terminal and the second input terminal are combined into one phase to form a live wire terminal, and the third input terminal and the fourth input terminal are combined into a zero line terminal, so that the three-phase six-switch PFC converter is suitable for single-phase alternating current input, and the original three-phase six-switch PFC converter is converted into a two-phase staggered parallel totem-pole PFC converter. The direction of the input voltage is judged by sampling the input voltage. In the positive half cycle of the grid voltage, the switching tubes Q4 and Q6 work as main switching tubes at a switching frequency, the body diodes of the switching tubes Q1 and Q3 are used as freewheeling diodes, and the switching tube Q2 is always conducted. In the negative half cycle of the grid voltage, the switching tubes Q1 and Q3 work as main switching tubes at a switching frequency, the body diodes of the switching tubes Q4 and Q6 are used as freewheeling diodes, and the switching tube Q5 is always conducted. The two phases are conducted in a phase-staggered mode of 180 degrees, and the PFC converter works in a Boost mode (a boosting mode) no matter in a positive half cycle or a negative half cycle of a grid voltage.

According to the on and off conditions of the switching tube, no matter in the positive half cycle or the auxiliary half cycle of the grid voltage, the converter of the first-stage topology has 4 working states:

1. the two bridge arm lower switching tubes Q4 and Q6 are simultaneously conducted, the switching tubes Q1 and Q3 and body diodes thereof are all in a cut-off state, two paths of input inductors L1 and L2 are used for energy storage and charging, the currents of the inductors L1 and L2 rise simultaneously, and at the moment, the energy flows to a next-stage circuit through the bus capacitor C1.

2. The switch tube Q4 is turned on, the switch tube Q6 is turned off, the switch tube Q1 and the body diode thereof are turned off, the switch tube Q3 and the body diode thereof are turned on to freewheel, at this time, the inductor L1 stores energy and the inductor current rises, and the inductor L2 discharges to supply power to the next-stage circuit and the output capacitor C1, so that the inductor current drops.

3. The switch tube Q6 is turned on, Q4 is turned off, Q1 and its body diode conduct freewheeling, Q3 and its body diode are turned off, at this time, the inductor L2 stores energy and the inductor current rises, and the inductor L1 discharges to supply power to the next stage circuit and the output capacitor C1 and the inductor current falls.

4. The switching tubes Q6 and Q4 are turned off at the same time, the switching tubes Q1 and Q3 and body diodes thereof are conducted and follow current, at the moment, the two paths of inductors L1 and L2 are in a discharging state, the inductor current is reduced, and energy flows from a power grid to the output bus capacitor C1 and a next-stage circuit.

As shown in fig. 2, in this embodiment, the DC-DC isolation converter is a phase-shifted full bridge circuit with zero-voltage switching, and includes switching tubes Q7, Q8, Q9, Q10, inductors L4, L5, a transformer T1, diodes D1, D2, D3, D4, and a capacitor C2.

The drains of the switching tubes Q7 and Q8 are connected to the first end of the capacitor C1, and the sources of the switching tubes Q9 and Q10 are connected to the second end of the capacitor C1.

The source of the switching tube Q7 and the drain of the switching tube Q9 are connected to one end of the primary winding of the transformer T1 via the inductor L4, and the source of the switching tube Q8 and the drain of the switching tube Q10 are connected to the other end of the primary winding of the transformer T1.

The secondary winding of the transformer T1 is connected to an inductor L5 and a capacitor C2 via a rectifier bridge formed by diodes D1, D2, D3, and D4.

One end of the secondary winding of the transformer T1 is connected to the anode of the diode D1 and the cathode of the diode D3, and the other end is connected to the anode of the diode D2 and the cathode of the diode D4.

Cathodes of the diodes D1 and D2 are connected to the first terminal of the inductor L5, and the second terminal of the inductor L5 is connected to the first terminal of the capacitor C2.

The anodes of the diodes D3 and D4 are connected to the second terminal of the capacitor C2.

In order to inhibit the oscillation of the secondary side output voltage of the transformer T1 and ensure that the converter operates more safely and stably, an RCD absorption circuit is arranged at the output end of the DC-DC isolation converter.

As shown in fig. 2, the RCD absorption circuit includes a resistor R1, a capacitor C3, and a diode D5, wherein an anode of the diode D5 is connected to a first end of the inductor L5, a cathode of the diode D5 is connected to a common connection end of the capacitor C3 and the resistor R1, another end of the capacitor C3 is connected to a second end of the capacitor C2, and another end of the resistor R1 is connected to a second end of the inductor L5. When the secondary oscillation voltage of the transformer is higher than a certain value, the diode D5 is turned on in the forward direction, and the absorption capacitor C3 starts to absorb the oscillation voltage and clamp the oscillation voltage. At the same time, the absorption circuit is continuously discharged through the resistor R1 to maintain the charge balance of the capacitor. When the RCD snubber circuit operates in a steady state, the voltage and energy across the snubber capacitor C3 remain balanced, i.e., the voltage rising when the snubber capacitor C3 clamps, can discharge to the original value before another oscillating voltage comes.

The DC-DC non-isolated converter is a Buck-Boost type topological converter and comprises a switching tube Q11, a diode D6, an inductor L6 and a capacitor C4, wherein the drain electrode of the switching tube Q11 is connected with the first end of the capacitor C2, the source electrode of the switching tube Q11 is connected with the first end of the inductor L6 and the negative electrode of the diode D6, the second end of the inductor L6 is connected with the second end of the capacitor C2, the positive electrode of the diode D6 is connected with the first end of the capacitor C4, and the second end of the capacitor C4 is connected with the second end of the inductor L6. The DC-DC non-isolated converter can secondarily regulate and guarantee the quality of electric energy output by a preceding stage circuit so as to output high-quality direct current with adjustable wide range, low output ripple and controlled precision.

MOS pipe is all selected for use to switch tube Q1-Q11, and its on-off control can refer to well-known technique, and its grid is connected with control module, through the turn-off of corresponding controllable switch tube Q1-Q11 of control strategy in order to realize the circuit function.

While the invention has been described with reference to the above embodiments, the scope of the invention is not limited thereto, and the above components may be replaced with similar or equivalent elements known to those skilled in the art without departing from the concept of the invention.

Claims

1. A three-level topology charging structure compatible with single-phase and three-phase AC inputs, comprising:

a first input terminal, a second input terminal, a third input terminal, and a fourth input terminal;

a three-phase PFC converter, an input end of which is connected with the first input terminal, the second input terminal and the third input terminal;

the input end of the DC-DC isolation converter is connected with the output end of the three-phase PFC converter;

the input end of the DC-DC non-isolated converter is connected with the output end of the DC-DC isolated converter and is used for outputting high-precision direct current;

a first switch S1 connected between the first input terminal and the second input terminal;

a second switch S2 connected between the three-phase PFC converter and a fourth input terminal;

when the first switch S1 and the second switch S2 are open, the charging structure is adapted for three-phase ac input; when the first switch S1 and the second switch S2 are closed, the charging structure is suitable for unidirectional ac input.

2. A three-stage topology charging architecture compatible with single-phase and three-phase ac inputs as claimed in claim 1, wherein said three-phase PFC converter is a three-phase six-switch PFC converter, and when said first switch S1 and second switch S2 are closed, the front stage of said charging architecture is converted to a two-phase interleaved totem-pole PFC converter.

3. A three-level topology charging architecture compatible with single-phase and three-phase ac inputs as recited in claim 2, wherein said DC-DC isolated converter is a phase-shifted full-bridge circuit with zero-voltage turn-on.

4. A three-level topology charging architecture compatible with single-phase and three-phase ac inputs according to claim 3, wherein said DC-DC non-isolated converter is a Buck-Boost type topology converter.

5. A three-level topology charging architecture compatible with single-phase and three-phase AC inputs according to claim 4, wherein an RCD snubber circuit is provided at the output of said DC-DC isolated converter.

6. The three-stage topology charging structure compatible with single-phase and three-phase alternating current input according to claim 5, wherein the three-phase PFC converter comprises inductors L1, L2 and L3, switching tubes Q1, Q2, Q3, Q4, Q5 and Q6, and a capacitor C1,

a first end of the inductor L1 is connected to the first input terminal, and a second end of the inductor L1 is connected to a source of the switching tube Q1 and a drain of the switching tube Q4;

a first end of the inductor L2 is connected to the second input terminal, and a second end of the inductor L2 is connected to a source of the switching tube Q3 and a drain of the switching tube Q6;

a first end of the inductor L3 is connected to the third input terminal, and a second end of the inductor L3 is connected to the source of the switching tube Q5 and the drain of the switching tube Q2;

the drains of the switching tubes Q1, Q3 and Q5 are respectively connected with the first end of the capacitor C1, and the sources of the switching tubes Q4, Q2 and Q6 are respectively connected with the second end of the capacitor C1.

7. The three-stage topology charging architecture compatible with single-phase and three-phase ac inputs of claim 6, wherein the first switch S1 is connected between the first terminal of the inductor L1 and the first terminal of the inductor L2, and the second switch S2 is connected between the second terminal of the inductor L3 and the fourth input terminal.

8. The three-stage topology charging structure compatible with single-phase and three-phase alternating current input according to claim 7, wherein the DC-DC isolation converter comprises switching tubes Q7, Q8, Q9, Q10, inductors L4, L5, a transformer T1, diodes D1, D2, D3 and D4, a capacitor C2;

the drains of the switching tubes Q7 and Q8 are connected with the first end of the capacitor C1, and the sources of the switching tubes Q9 and Q10 are connected with the second end of the capacitor C1;

the source of the switching tube Q7 and the drain of the switching tube Q9 are connected with one end of the primary coil of the transformer T1 through the inductor L4, and the source of the switching tube Q8 and the drain of the switching tube Q10 are connected with the other end of the primary coil of the transformer T1;

one end of a secondary winding of the transformer T1 is connected with the anode of the diode D1 and the cathode of the diode D3, and the other end of the secondary winding is connected with the anode of the diode D2 and the cathode of the diode D4;

cathodes of the diodes D1 and D2 are connected to a first end of the inductor L5, and a second end of the inductor L5 is connected to a first end of the capacitor C2;

9. A three-stage topology charging structure compatible with single-phase and three-phase ac input according to claim 8, wherein said RCD absorption circuit comprises a resistor R1, a capacitor C3, and a diode D5, wherein an anode of said diode D5 is connected to a first end of said inductor L5, a cathode of said diode D5 is connected to a common connection end of said capacitor C3 and said resistor R1, another end of said capacitor C3 is connected to a second end of said capacitor C2, and another end of said resistor R1 is connected to a second end of said inductor L5.

10. The three-stage topology charging structure compatible with single-phase and three-phase alternating current input according to claim 9, wherein the DC-DC non-isolated converter comprises a switch Q11, a diode D6, an inductor L6 and a capacitor C4, a drain of the switch Q11 is connected to a first terminal of the capacitor C2, a source of the switch Q11 is connected to a first terminal of the inductor L6 and a cathode of the diode D6, a second terminal of the inductor L6 is connected to a second terminal of the capacitor C2, an anode of the diode D6 is connected to the first terminal of the capacitor C4, and a second terminal of the capacitor C4 is connected to the second terminal of the inductor L6.