TWI820758B - Dual-input power converter, dual-input three-phase power converter and method of operating the same - Google Patents

Abstract

A dual-input power switching converter is coupled to a DC power source and an AC power source. The converter includes a first inductor, a second inductor, a first T-type converter, a second T-type converter, and a first switch. A first end of the first inductor is connected to a first node, and a second end thereof is coupled a positive terminal of the DC power source or the AC power source through a first switching switch. A first end of the second inductor is connected to a second node, and a second end thereof is coupled to a negative terminal of the DC power source or the AC power source through a second switching switch. The first T-type converter is connected to the first node, a third node, a fourth node, and a neutral node. The second T-type converter is connected to the second node, the third node, the fourth node, and the neutral node. A first node of the first switch is connected to the first node, and a second node thereof is connected to the second node.

Description

Dual-input power converter, dual-input three-phase power converter and operation method thereof

The present invention relates to a power converter and an operating method thereof, in particular to a dual-input power converter capable of both AC and DC and an operating method thereof.

Please refer to Figure 1, which is a circuit block diagram of an existing uninterruptible power supply system (UPS). The uninterruptible power supply system includes a DC-DC conversion circuit 91 , an AC-DC conversion circuit 92 and an inverter 93 . The DC-DC conversion circuit 91 is used to perform power factor correction (PFC) and DC-DC conversion on the battery voltage (V _BAT+ , V _BAT- ), so that the converted DC power charges the energy storage capacitor to generate the bus voltage V _BUS+ , V _BUS- to inverter 93. The AC-DC conversion circuit 92 is used to perform power factor correction and AC-DC conversion on the commercial power supply (AC power supply) V _AC , so that the converted DC power charges the energy storage capacitor to generate bus voltages V _BUS+ and V _BUS- for the inverter. Device 93. Next, the inverter 93 converts the bus voltages V _BUS+ and V _BUS- into output voltages for the load (not shown). Due to the use of two sets of converters, there are shortcomings such as low component usage, high cost and bulky size.

For this reason, how to design a dual-input power converter and its operation method to solve the problems and technical bottlenecks of the existing technology is an important issue in the industry.

One object of the present invention is to provide a dual-input power converter to solve the problems of the prior art.

In order to achieve the aforementioned purpose, the dual-input power converter proposed by the present invention couples the DC power supply and the AC power supply. The converter includes a first inductor, a second inductor, a first T-shaped converter, a second T-shaped converter and a first switch. The first end of the first inductor is connected to the first node, and the second end is coupled to the positive terminal of the DC power supply or the AC power supply. The first end of the second inductor is connected to the second node, and the second end is coupled to the negative terminal of the DC power supply or the AC power supply. The first T-shaped converter connects the first node, the third node, the fourth node and the neutral point. The second T-shaped converter connects the second node, the third node, the fourth node and the neutral point. The first terminal of the first switch is connected to the first node, and the second terminal is connected to the second node.

Another object of the present invention is to provide a dual-input three-phase three-wire power converter, including the dual-input power converter disclosed above. The neutral point, positive bus voltage and negative bus voltage of the three dual input power converters are connected to each other. The AC power supply includes a three-phase power supply, and three dual-input power converters are respectively coupled to the three-phase power supply.

Another object of the present invention is to provide a dual-input three-phase four-wire power converter, including the dual-input power converter disclosed above. The neutral points, the positive bus voltage and the negative bus voltage, and the positive terminal and the negative terminal of the DC power supply of the three dual-input power converters are connected to each other. The AC power supply includes a three-phase power supply, and three dual-input power converters are respectively coupled to the three-phase power supply.

Through the proposed dual-input power converter and dual-input three-phase power converter, it is possible to realize common components operating in the shared AC power supply mode and DC power supply mode. It only needs to switch the input terminal through a switch or relay, and the same group can be shared. The circuit architecture achieves the advantages of saving volume and reducing costs.

Another object of the present invention is to provide an operating method of a dual-input power converter to solve the problems of the prior art.

In order to achieve the purpose of the disclosure, the operating method of the dual-input power converter proposed by the present invention is used for the disclosure of the dual-input power converter. The operation method includes: when switching to the DC power supply, controlling the first switch to be turned on, the second switch of the first T-shaped converter and the third switch of the second T-shaped converter to be turned off, The DC power supply stores energy in the first inductor and the second inductor through the first switch; and the first switch, the second switch of the first T-shaped converter and the third switch of the second T-shaped converter are controlled to turn off, so that the DC power supply , the first inductor and the second inductor discharge energy to the first capacitor and the second capacitor.

Another object of the present invention is to provide an operating method of a dual-input power converter to solve the problems of the prior art.

In order to achieve the purpose of the disclosure, the operating method of the dual-input power converter proposed by the present invention is used for the disclosure of the dual-input power converter. The operation method includes: when switching to the DC power supply, controlling the first switch to be turned on, the second switch of the first T-shaped converter and the third switch of the second T-shaped converter to be turned off, so that the DC power supply passes through the first switch. The first inductor and the second inductor store energy; control the first switch and the second switch to turn off and control the third switch to turn on, so that the DC power supply, the first inductor and the second inductor discharge energy to the first capacitor; and control the first switch The third switch is turned off and the second switch is controlled to be turned on, so that the DC power supply, the first inductor and the second inductor discharge energy to the second capacitor.

Through the operation method of the proposed dual-input power converter, it is possible to realize the common components operating in the AC power supply mode and the DC power supply mode by sharing, and only need to switch the input terminal through a switch or relay, and the same set of circuit architecture can be shared to achieve savings. size and cost reduction.

In order to further understand the technology, means and effects adopted by the present invention to achieve the intended purpose, please refer to the following detailed description and drawings of the present invention. It is believed that the purpose, features and characteristics of the present invention can be understood in depth and For specific understanding, however, the attached drawings are only for reference and illustration, and are not intended to limit the present invention.

Vdc: DC power supply

Vac: AC power

L ₁ : first inductor

L ₂ : Second inductor

T1: The first T-converter

T2: Second T-type converter

11:First switch

12:Second switch

13:Third switch

C ₁ : first capacitor

C ₂ : Second capacitor

N ₁ : first node

N ₂ : second node

N ₃ : The third node

N ₄ : fourth node

N: neutral point

SW ₁ : First input switch

SW ₂ : Second input switch

V _BAT+ : positive terminal

V _BAT- : negative terminal

V _BUS+ : Positive bus voltage

V _BUS- : Negative bus voltage

S ₁ : first transistor

S ₂ : Second transistor

S ₃ : The third transistor

S ₄ : The fourth transistor

S ₅ : fifth transistor

S ₆ : The sixth transistor

D ₁ : first diode

D ₂ : Second diode

D ₃ : The third diode

D ₄ : The fourth diode

L31, L41: energy storage path

L32, L42, L43: energy release path

L51, L53, L61, L63: energy storage path

L52, L54, L62, L64: energy release path

S11-S12, S21-S23: steps

91: DC-DC conversion circuit

92: AC-DC conversion circuit

93:Inverter

Figure 1 is a circuit block diagram of the existing uninterruptible power supply system architecture.

Figure 2 is a circuit diagram of the dual-input power converter of the present invention.

FIG. 3 is a circuit diagram of the first embodiment of the present invention in which the dual-input power converter operates in the DC power supply mode and the first inductor and the second inductor store and release energy.

4 is a circuit diagram of a second embodiment of the present invention in which the dual-input power converter operates in the DC power supply mode and the first inductor and the second inductor store and release energy.

5A is a circuit diagram of the first inductor storing and releasing energy when the dual-input power converter of the present invention operates in the positive half cycle of the AC power supply mode.

5B is a circuit diagram of the second inductor storing and releasing energy when the dual-input power converter of the present invention operates in the positive half cycle of the AC power supply mode.

6A is a circuit diagram of the first inductor storing and releasing energy when the dual-input power converter of the present invention operates in the negative half cycle of the AC power supply mode.

6B is a circuit diagram of the second inductor storing and releasing energy when the dual-input power converter of the present invention operates in the negative half cycle of the AC power supply mode.

FIG. 7 is a circuit diagram of the dual-input power converter of the present invention operating on three-phase three-wire input.

Figure 8 is a circuit diagram of the dual-input power converter operating on three-phase four-wire input according to the present invention.

FIG. 9 is a flow chart of the first embodiment of the operating method when the dual-input power converter of the present invention is powered by a DC power supply.

FIG. 10 is a flow chart of the second embodiment of the operating method of the dual-input power converter of the present invention when it is powered by a DC power supply.

The technical content and detailed description of the present invention are as follows with reference to the drawings.

Please refer to Figure 2, which is a circuit diagram of the dual-input power converter of the present invention. The dual-input power converter is coupled to the DC power supply Vdc and the AC power supply Vac. Among them, the AC power supply Vac can be AC mains power, and the DC power supply Vdc can be a battery. The battery voltages provided by it are represented by V _BAT+ and V _BAT- . The converter includes a first inductor L ₁ , a second inductor L ₂ , a first T-type converter T1 , a second T-type converter T2 , a first switch 11 , a first capacitor C ₁ and a second capacitor C ₂ .

As shown in FIG. 2 , the first end of the first inductor L ₁ is connected to the first node N ₁ , and the second end is coupled to the positive terminal V _BAT+ of the DC power supply Vdc or the AC power supply Vac. The first end of the second inductor L ₂ is connected to the second node N ₂ , and the second end is coupled to the negative terminal V _BAT- of the DC power supply Vdc or the AC power supply Vac.

The first T-type converter T1 connects the first node N ₁ , the third node N ₃ , the fourth node N4 and the neutral point N. The second T-type converter T2 connects the second node N ₂ , the third node N ₃ , the fourth node N4 and the neutral point N. The third switch 13 includes a fifth switch S ₅ and a sixth switch S ₆ connected in series. Both ends of the third switch 13 are connected to the second node N ₂ and the neutral point N respectively. The first terminal of the first switch 11 is connected to the first node N ₁ , and the second terminal is connected to the second node N ₂ .

The first T-type converter T1 includes a first diode D ₁ , a second diode D ₂ and a second switch 12 . The first cathode of the first diode D ₁ is connected to the third node N ₃ , and the first anode is connected to the first node N ₁ . The second cathode of the second diode D ₂ is connected to the first node N ₁ , and the second anode is connected to the fourth node N4. The first terminal of the second switch 12 is connected to the first node N ₁ , and the second terminal is connected to the neutral point N.

The second T-type converter T2 includes a third diode D ₃ , a fourth diode D ₄ and a third switch 13 . The third cathode of the third diode D ₃ is connected to the third node N ₃ , and the third anode is connected to the second node N ₂ . The fourth cathode of the fourth diode D ₄ is connected to the second node N ₂ , and the fourth anode is connected to the fourth node N ₄ . The first terminal of the third switch 13 is connected to the second node N ₂ , and the second terminal is connected to the neutral point N.

The first switch 11 includes a first transistor S ₁ and a second transistor S ₂ connected in series. The first transistor S ₁ is connected to the first node N ₁ , and the second transistor S ₂ is connected to the second node N ₂ . The second switch 12 includes a third transistor S ₃ and a fourth transistor S ₄ connected in series. The third transistor S ₃ is connected to the first node N ₁ , and the fourth transistor S ₄ is connected to the neutral point N. The third switch 13 includes a fifth transistor S ₅ and a sixth transistor S ₆ connected in series. The fifth transistor S ₅ is connected to the second node N ₂ , and the sixth transistor S ₆ is connected to the neutral point N.

The first transistor S ₁ and the second transistor S ₂ , the third transistor S ₃ and the fourth transistor S ₄ , and the fifth transistor S ₅ and the sixth transistor S ₆ are connected back to back to form bidirectional conduction respectively. A switch set. In one embodiment, the transistors S ₁ , S ₂ , S ₃ , S ₄ , S ₅ , and S ₆ are N-channel enhancement type power MOSFETs. However, there are common Those with knowledge can replace the N-channel transistor with a P-channel transistor and appropriately modify the control signal level according to actual needs, but are not limited to this.

The first capacitor C ₁ and the second capacitor C ₂ are coupled to the output bus to provide voltages V _BUS+ and V _BUS- of the output bus. The first end of the first capacitor C ₁ is connected to the third node N ₃ , which is the positive voltage end of the output bus. The second end of the first capacitor C ₁ is connected to the neutral point N, the second switch 12 and the third switch 13 . The first end of the second capacitor C ₂ is connected to the neutral point N, the second switch 12 and the third switch 13 , and the second end of the second capacitor C ₂ is connected to the fourth node N ₄ , that is, the negative voltage end of the output bus.

The dual-input power converter further includes a first input switch SW1 and a second input switch SW2. When the DC power supply Vdc supplies power, the second terminal of the first inductor L ₁ is coupled to the positive terminal V _BAT+ of the DC power supply Vdc through the first input switch SW1, and the two terminals of the second inductor L ₂ are coupled through the second input switch SW2. Connect to the negative terminal V _BAT- of the DC power supply Vdc. When the AC power supply Vac supplies power, the second end of the first inductor L ₁ is coupled to the AC power supply Vac through the first input switch SW1, and the second end of the second inductor L ₂ is coupled to the AC power supply Vac through the second input switch SW2.

As shown in Figure 3 and Figure 4, when the dual-input power converter operates in the DC power supply mode (when the DC power supply Vdc is powered), it is the battery power supply mode. The first switch 11 is turned on, and the first T-shaped converter T1 and the The two T-shaped converters T2 are turned off, so that the DC power supply Vdc stores energy in the first inductor L ₁ and the second inductor L ₂ . The first input switch SW ₁ and the second input switch SW ₂ are turned on to couple the positive terminal V _BAT+ and the negative terminal V _BAT- of the battery respectively. The first input switch SW ₁ and the second input switch SW ₂ can be implemented by relays.

As shown in Figure 3, in the DC power supply mode, the first end of the first inductor L ₁ is coupled to the positive terminal V _BAT+ , and the first end of the second inductor L ₂ is coupled to the negative terminal V _BAT -. When the first transistor S ₁ and the second transistor S ₂ of the first switch 11 are turned on, the electric energy provided by the battery stores energy in the first inductor L ₁ and the second inductor L ₂ , wherein the energy storage path is L31. The energy storage path L31 formed by the first switch 11 being turned on is the shortest path and passes through the fewest components. Therefore, the energy storage path L31 has the lowest power loss in terms of the overall dual-input power converter. At this time, the first transistor S ₁ is the main switch, and the second transistor S ₂ is used as a synchronous rectifier and can prevent the reverse voltage when the AC power supply Vac is input, or the second transistor S ₂ can be replaced with a diode, The same circuit operation can still be achieved. Furthermore, at this time, the third transistor S ₃ and the fourth transistor S ₄ of the second switch 12 are turned off, and the fifth transistor S ₅ and the sixth transistor S ₆ of the third switch 13 are turned off. However, if it is necessary to balance the voltage of the output bus, the third transistor S ₃ , the fourth transistor S ₄ , the fifth transistor S ₅ and the sixth transistor S ₆ can be used as active switches.

After the first inductor L ₁ and the second inductor L ₂ store energy, the first switch 11 , the second switch 12 and the third switch 13 are turned off, and the DC power supply Vdc, the first inductor L ₁ and the second inductor L ₂ pass through The first diode D ₁ and the fourth diode D ₄ discharge energy to the first capacitor C ₁ and the second capacitor C ₂ to generate the positive bus voltage V _BUS+ at the first terminal of the first capacitor C ₁ and the first terminal of the first capacitor C 1 . The second terminal of the second capacitor C ₂ generates the negative bus voltage V _BUS- , and the energy release path is L32. Since the neutral point N is zero voltage or ground, the voltage across the first capacitor C ₁ is equal to the positive bus voltage V _BUS+ , and the voltage across the second capacitor C ₂ is equal to the negative bus voltage V _BUS- .

In another embodiment of energy storage and energy release, as shown in Figure 4, similarly, the first transistor _S1 and the second transistor _S2 are connected, the first transistor S1 is the main switch, and the second transistor _S2 is turned on. Crystal S ₂ is used as a synchronous rectifier. The electric energy provided by the battery stores energy in the first inductor L ₁ and the second inductor L ₂ . The electric energy provided by the battery stores energy in the first inductor L ₁ and the second inductor L ₂ . The energy storage path for L41. Similarly, the energy storage path L41 formed by turning on the first switch 11 is the shortest path and passes through the fewest components. Therefore, the energy storage path L41 has the lowest power loss in terms of the entire dual-input power converter.

After the first inductor L ₁ and the second inductor L ₂ store energy, the first switch 11 and the second switch 12 are turned off, and the DC power supply Vdc, the first inductor L ₁ and the second inductor L ₂ pass through the first diode. D ₁ and the third switch 13 release energy to the first capacitor C ₁ to generate a positive bus voltage V _BUS+ at the first terminal of the first capacitor C ₁ , where the energy release path is L42.

After the positive bus voltage V _BUS+ is generated at the first end of the first capacitor C ₁ , the first switch 11 and the third switch 13 are turned off, and the DC power supply Vdc, the first inductor L ₁ and the second inductor L ₂ pass through the second switch 12 and the fourth diode D ₄ release energy to the second capacitor C ₂ to generate a negative bus voltage V _BUS- at the second end of the second capacitor C ₂ , where the energy release path is L43.

Incidentally, the order in which the positive bus voltage V _BUS+ is generated at the first terminal of the first capacitor C ₁ and the negative bus voltage V _BUS- is generated at the second terminal of the second capacitor C ₂ is not limited to the above description, which means The negative bus voltage V _BUS- can be generated first, and then the positive bus voltage V _BUS+ can be generated. Furthermore, since the voltage on the first capacitor C ₁ and the voltage on the second capacitor C ₂ are usually the same (or ideally substantially the same), the voltage on the first capacitor C ₁ as shown in Figure 3 is usually adopted. and the second capacitor _C2 releases energy. However, if the voltage on the first capacitor C ₁ is significantly lower than the voltage on the second capacitor C ₂ , then the first capacitor C ₁ is released as shown in Figure 4 to increase the voltage on the first capacitor C ₁ voltage. In the same way, if the voltage on the second capacitor C ₂ is significantly lower than the voltage on the first capacitor C ₁ , then the energy release of the second capacitor C ₂ is used as shown in Figure 4 to increase the voltage of the second capacitor C ₂ voltage on. Thereby, the voltage on the first capacitor C ₁ and the voltage on the second capacitor C ₂ can be controlled to achieve a voltage balance effect.

As shown in Figures 5A to 6B, when the dual-input power converter operates in the AC power supply mode (when the AC power supply Vac is powered), it is the mains power supply mode. The first input switch SW ₁ and the second input switch SW ₂ are turned on to respectively AC power Vac coupled to the battery. In the mains power supply mode, the first transistor S ₁ and the second transistor S ₂ are in an off state.

As shown in Figure 5A and Figure 5B, it is the operation mode when the AC power supply Vac (AC mains) is input in the positive half cycle. As shown in Figure 5A, the third transistor S ₃ and the fourth transistor S ₄ are connected, and the fourth transistor S ₄ is used as a synchronous rectifier diode. The AC power supply Vac stores energy in the first inductor L ₁ , where the stored energy The available path is L51. When the third transistor S ₃ and the fourth transistor S ₄ are turned off (especially the third transistor S ₃ is turned off), the current of the first inductor L ₁ freewheels and passes through the first diode D ₁ to the first Capacitor C ₁ releases energy, and the energy release path is L52.

As shown in Figure 5B, the fifth transistor _S5 and the sixth transistor _S6 are connected, and the sixth transistor _S6 is used as a synchronous rectifier diode. The AC power supply Vac stores energy in the second inductor _L2 , where the stored energy The available path is L53. When the fifth transistor S ₅ and the sixth transistor S ₆ are turned off (especially the fifth transistor S ₅ is turned off), the current of the second inductor L ₂ continues to flow through the third diode D ₃ to the first Capacitor C ₁ releases energy, and the energy release path is L54.

As shown in Figure 6A and Figure 6B, it is the operation mode when the AC power supply Vac (AC mains) is input in the negative half cycle. As shown in Figure 6A, the third transistor S ₃ and the fourth transistor S ₄ are connected. The third transistor S ₃ is used as a synchronous rectifier diode. The AC power supply Vac stores energy in the first inductor L _{1. The stored energy is stored in the first inductor L 1} . The available path is L61. When the third transistor S ₃ and the fourth transistor S ₄ are turned off (especially the fourth transistor S ₄ is turned off), the current of the first inductor L ₁ freewheels and passes through the second diode D ₂ to the second transistor S 4 . Capacitor C ₂ releases energy, and the energy release path is L62.

As shown in Figure 6B, the fifth transistor _S5 and the sixth transistor _S6 are connected, and the fifth transistor _S5 is used as a synchronous rectifier diode. The AC power supply Vac stores energy in the second inductor _L2 , where the stored energy The available path is L63. When the fifth transistor S ₅ and the sixth transistor S ₆ are turned off (especially the sixth transistor S ₆ is turned off), the current of the second inductor L ₂ continues to flow through the fourth diode D ₄ to the second Capacitor C ₂ releases energy, and the energy release path is L64.

Therefore, by operating the circuit in the out-of-phase control, the voltage ripple of the first capacitor C ₁ and the second capacitor C ₂ can be further effectively reduced, and the overall circuit volume can be reduced. This circuit can also be used for DC input, so it has advantages in size and cost.

Please refer to FIG. 7 and FIG. 8 , which are respectively a circuit diagram of the dual-input power converter of the present invention operating on a three-phase three-wire input and a circuit diagram of operating on a three-phase four-wire input. As shown in Figures 7 and 8, in a three-phase input system, the circuit structure of each phase can be the same as the single-phase circuit structure shown above. In other words, by using three sets of single-phase circuit structures, it can be applied to three In the architecture of three-phase three-wire input and three-phase four-wire input. Since the operation of each phase circuit is the same as that of the single-phase circuit shown above, please refer to the previous description and will not be repeated here.

Please refer to FIG. 9 , which is a flow chart of the first embodiment of the operating method when the dual-input power converter of the present invention is powered by a DC power supply. The operation method includes: when switching to the DC power supply Vdc, controlling the first switch 11 to be turned on and the second switch 12 of the first T-type converter T1 and the third switch 13 of the second T-type converter T2 to be turned off, so that The DC power supply Vdc stores energy in the first inductor L ₁ and the second inductor L ₂ through the first switch 11 (step S11).

Then the first switch 11, the second switch 12 of the first T-type converter T1 and the third switch 13 of the second T-type converter T2 are controlled to turn off, so that the DC power supply Vdc, the first inductor L ₁ and the second inductor L ₂ discharges energy to the first capacitor C ₁ and the second capacitor C ₂ (step S12).

Please refer to FIG. 10 , which is a flow chart of the second embodiment of the operating method of the dual-input power converter of the present invention when it is powered by a DC power supply. The operation method includes: when switching to the DC power supply Vdc, controlling the first switch 11 to be turned on and the second switch 12 of the first T-type converter T1 and the third switch 13 of the second T-type converter T2 to be turned off, so that The DC power supply Vdc stores energy in the first inductor L ₁ and the second inductor L ₂ through the first switch 11 (step S21).

Then, the first switch 11 and the second switch 12 are controlled to be turned off and the third switch 13 is controlled to be turned on, so that the DC power supply Vdc, the first inductor L ₁ and the second inductor L ₂ discharge energy to the first capacitor C ₁ (step S22). Then, the first switch 11 and the third switch 13 are controlled to be turned off and the second switch 12 is controlled to be turned on, so that the DC power supply Vdc, the first inductor L ₁ and the second inductor L ₂ discharge energy to the second capacitor C ₂ (step S23) . The order of step S22 and step S23 is not limited to the order described above, which means that step S23 can be executed earlier than step S22.

To sum up, the present invention has the following features and advantages:

1. Share common components in AC power supply mode and DC power supply mode operation. Specifically, you only need to switch the input terminal through a switch or relay, and you can share the same set of circuit architecture, achieving the advantages of saving volume and reducing costs.

2. By operating the circuit in out-of-phase control, the voltage ripple of the first capacitor C ₁ and the second capacitor C ₂ can be further effectively reduced, thereby reducing the overall circuit volume.

3. The energy storage path formed by the first switch being turned on is the shortest path and passes through the fewest components. Therefore, for the entire dual-input power converter, this energy storage path has the lowest power loss.

The above are only detailed descriptions and drawings of the preferred embodiments of the present invention. However, the characteristics of the present invention are not limited thereto and are not used to limit the present invention. The entire scope of the present invention should be determined by the following patent application scope. Subject to the present invention, all embodiments that are within the spirit of the patentable scope of the present invention and similar changes thereof shall be included in the scope of the present invention. Anyone familiar with the art can easily think of such changes or modifications in the field of the present invention. Modifications may be covered by the following patent scope of this case.

Vdc: DC power supply

Vac: AC power

L ₁ : first inductor

L ₂ : Second inductor

T1: The first T-converter

T2: Second T-type converter

11:First switch

12:Second switch

13:Third switch

C ₁ : first capacitor

C ₂ : Second capacitor

N ₁ : first node

N ₂ : second node

N ₃ : The third node

N ₄ : fourth node

N: neutral point

SW ₁ : First switch

SW ₂ : Second switch

V _BAT+ : positive terminal

V _BAT- : negative terminal

V _BAT+ : positive terminal

V _BAT- : negative terminal

S ₁ : first transistor

S ₂ : Second transistor

S ₃ : The third transistor

S ₄ : The fourth transistor

S ₅ : fifth transistor

S ₆ : The sixth transistor

D ₁ : first diode

D ₂ : Second diode

D ₃ : The third diode

D ₄ : The fourth diode

Claims (13)

A dual-input power converter is coupled to a DC power supply and an AC power supply. The converter includes: a first inductor, the first end of which is connected to a first node, and the second end is coupled to a positive terminal of the DC power supply. Or the AC power supply; a second inductor with a first end connected to a second node and a second end coupled to a negative terminal of the DC power supply or the AC power supply; a first T-shaped converter connected to the first node , a third node, a fourth node and a neutral point; a second T-type converter connecting the second node, the third node, the fourth node and the neutral point; and a first switch , the first end of which is connected to the first node, and the second end of which is connected to the second node. The dual-input power converter of claim 1, wherein when the DC power supply supplies power, the first switch is turned on, the first T-type converter and the second T-type converter are turned off, so that the DC The power supply stores energy in the first inductor and the second inductor. The dual-input power converter as claimed in claim 1, further comprising a first input switch and a second input switch, wherein: when the DC power supply supplies power, the second end of the first inductor passes through the first input switch. The switch is coupled to the positive terminal of the DC power supply, and the second end of the second inductor is coupled to the negative terminal of the DC power supply through the second input switch; and when the AC power supply is powered, the first inductor The second end is coupled to the AC power source through the first input switch, and the second end of the second inductor is coupled to the AC power source through the second input switch. A dual-input power converter as described in claim 1, wherein: The first T-type converter includes: a first diode with a first cathode connected to the third node and a first anode connected to the first node; a second diode with a second cathode connected to the first node. node, the second anode is connected to the fourth node; and a second switch, the first end of which is connected to the first node, and the second end is connected to the neutral point; the second T-type converter includes: a third two-pole a fourth diode, the third cathode of which is connected to the third node, and the third anode of which is connected to the second node; a fourth diode, whose fourth cathode is connected to the second node, and the fourth anode is connected to the fourth node; and a fourth diode. Three switches, the first end of which is connected to the second node, and the second end of which is connected to the neutral point. The dual-input power converter of claim 4, wherein: the first switch includes a first transistor and a second transistor connected in series, the first transistor is connected to the first node, and the second The transistor is connected to the second node; the second switch includes a third transistor and a fourth transistor connected in series, the third transistor is connected to the first node, and the fourth transistor is connected to the neutral point ; The third switch includes a fifth transistor and a sixth transistor connected in series, the fifth transistor is connected to the second node, and the sixth transistor is connected to the neutral point; and the first transistor The second transistor, the third transistor, the fourth transistor, the fifth transistor and the sixth transistor are connected back-to-back to respectively form a set of switch groups for bidirectional conduction. The dual-input power converter as claimed in claim 4, further comprising: a first capacitor, a first end of which is connected to the third node, and a second end of which is connected to the neutral point, the second switch and the third switch; as well as A second capacitor has a first end connected to the neutral point, the second switch and the third switch, and a second end connected to the fourth node. The dual-input power converter of claim 6, wherein when the DC power supply supplies power, after the first inductor and the second inductor store energy, the first switch, the second switch and the third switch are turned off. When the DC power supply, the first inductor and the second inductor are turned off, energy is released to the first capacitor and the second capacitor through the first diode and the fourth diode, so that the first capacitor is A positive bus voltage is generated at the first terminal and a negative bus voltage is generated at the second terminal of the second capacitor. The dual-input power converter of claim 6, wherein when the DC power supply supplies power, after the first inductor and the second inductor store energy, the first switch and the second switch are turned off, and the DC power supply The first inductor and the second inductor discharge energy to the first capacitor through the first diode and the third switch to generate a positive bus voltage at the first end of the first capacitor. The dual-input power converter as claimed in claim 8, wherein when the DC power supply supplies power, after the first terminal of the first capacitor generates the positive bus voltage, the first switch and the third switch are turned off, The DC power supply, the first inductor and the second inductor discharge energy to the second capacitor through the second switch and the fourth diode to generate a negative bus voltage at the second end of the second capacitor. A dual-input three-phase three-wire power converter, including: three dual-input power converters as described in claims 1 to 9, wherein: the neutral point, the positive bus voltage of the three dual-input power converters and The negative bus voltages are connected to each other; the AC power source includes a three-phase power source, and the three dual-input power converters are respectively coupled to the three-phase power source. A dual-input three-phase four-wire power converter, including: three dual-input power converters as described in claim items 1 to 9, wherein: The neutral points of the three dual-input power converters, the positive bus voltage and the negative bus voltage, and the positive terminal and the negative terminal of the DC power supply are connected to each other; the AC power supply includes a three-phase power supply, and the three The dual-input power converter is coupled to the three-phase power supply respectively. An operating method of a dual-input power converter, for the dual-input power converter as described in claims 1 to 11, the operating method includes: when switching to the DC power supply, controlling the first switch to conduct, the first The second switch of the T-type converter and the third switch of the second T-type converter are turned off, so that the DC power supply stores energy on the first inductor and the second inductor through the first switch; and controlling the The first switch, the second switch of the first T-type converter and the third switch of the second T-type converter are turned off, so that the DC power supply, the first inductor and the second inductor are opposite to the first The capacitor and the second capacitor discharge energy. An operating method of a dual-input power converter, for the dual-input power converter as described in claims 1 to 11, the operating method includes: when switching to the DC power supply, controlling the first switch to conduct, the first The second switch of the T-type converter and the third switch of the second T-type converter are turned off, so that the DC power supply stores energy on the first inductor and the second inductor through the first switch; controlling the third A switch and the second switch are turned off and the third switch is controlled to be turned on so that the DC power supply, the first inductor and the second inductor discharge energy to the first capacitor; and the first switch and the third switch are controlled Turn off and control the second switch to turn on, so that the DC power supply, the first inductor and the second inductor discharge energy to the second capacitor.

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