Three-phase power energy storage converter circuit topology

Abstract

The invention belongs to the technical field of converters, and discloses a three-phase power energy storage converter circuit topology which comprises a port A, a port B and a port C. The port A is connected with one end of an inductor L13, the other end of the inductor L13 is connected with a pin 2 of a switch tube N1 and a pin 1 of a switch tube N2, the port B is connected with one end of an inductor L14, the other end of the inductor L14 is connected with a pin 2 of a switch tube N5 and a pin 1 of a switch tube N3, and the switch tube N5 is connected with a pin 1 of a switch tube N3. A port C is connected with one end of an inductor L15, the other end of the inductor L15 is connected with a pin 2 of a switching tube N6 and a pin 1 of a switching tube N4, and a pin 1 of a switching tube N1 is connected with a pin 1 of a switching tube N5, a pin 1 of the switching tube N6, one end of a capacitor C3, one end of a capacitor C1 and one end of an inductor L1. The beneficial effects of the invention are that better reliability and high efficiency are realized, the cost can be reduced, the size is reduced, and the circuit structure and software control are simplified.

Description

Technical Field

[0001] The present invention relates to the technical field of converters, and in particular to a circuit topology of a three-phase energy storage converter. Background Art

[0002] With the rapid development of switching power supply technology, the frequency of high-power switching power supplies in the market is increasing, and energy storage converter power supplies are one of the new energy sources in the market. In recent years, the power of energy storage power supplies has become increasingly larger. In modern high-power power supply applications, the input voltage usually uses three-phase AC input, and then after three-phase Vienna PFC topology rectification, the subsequent LLC circuit performs DC-DC conversion to obtain the required DC output voltage.

[0003] In applications such as energy storage inverters, off-grid inverters, and grid-connected and off-grid inverters, inverter links such as inverter H-bridge circuits are generally used, and the MPPT part of the Boost boost circuit to the busbar is implemented. The achievable working modes can be solar energy or city power charging the battery, solar energy inverter grid-connected or off-grid output, battery inverter grid-connected or off-grid output, etc. In some low-cost module applications, LLC is usually used for bidirectional conversion to meet the inverter function; the performance of this LLC+H-bridge circuit mode is good, but the cost will be relatively high; there are also solutions that use a separate half-bridge LLC or full-bridge LLC to achieve inversion. This mode can also achieve related inversion conversion, but the voltage inverted by LLC is not stable enough, resulting in a certain voltage fluctuation in the output voltage, which does not meet the requirements on some instruments and equipment that require high precision. For charging, output paralleling, grid-connected applications, etc. within the battery voltage range, there are great restrictions on the performance of the inverter, and it is easy to have various protections or even damage.

[0004] Therefore, it is necessary to provide a three-phase energy storage converter circuit topology to achieve better reliability and high efficiency, reduce costs, reduce volume, and simplify circuit structure and software control. Summary of the invention

[0005] The present invention discloses a three-phase energy storage converter circuit topology, which relates to the field of power electronics technology and is mainly used in switching power supplies. It is widely used in the fields of energy storage inverters, chargers, off-grid inverters and grid-connected and off-grid inverters, and can effectively solve the technical problems involved in the background technology.

[0006] To achieve the above object, the technical solution of the present invention is:

[0007] A three-phase energy storage converter circuit topology includes a port A, a port B and a port C, wherein the port A is connected to one end of an inductor L13, the other end of the inductor L13 is connected to the pin 2 of a switch tube N1 and the pin 1 of a switch tube N2, the port B is connected to one end of an inductor L14, the other end of the inductor L14 is connected to the pin 2 of a switch tube N5 and the pin 1 of a switch tube N3, the port C is connected to one end of an inductor L15, the other end of the inductor L15 is connected to the pin 2 of a switch tube N6 and the pin 1 of a switch tube N4 Pin 1; Pin 1 of the switch tube N1 is connected to Pin 1 of the switch tube N5, Pin 1 of the switch tube N6, one end of the capacitor C3, one end of the capacitor C1 and one end of the inductor L1, the other end of the inductor L1 is connected to Pin 1 of the switch tube Q108 and one end of the capacitor C14, the other end of the capacitor C15 is connected to Pin 1 of the transformer T1, Pin 2 of the transformer T1 is connected to Pin 2 of the switch tube Q108 and port GND, the other end of the capacitor C3 is connected to the other end of the capacitor C1 , one end of the capacitor C4, one end of the capacitor C5 and one end of the inductor L2, the other end of the inductor L2 is connected to the pin 1 of the switch tube Q109 and one end of the capacitor C17, the other end of the capacitor C17 is connected to the pin 1 of the transformer T2, the pin 2 of the transformer T2 is connected to the pin 2 of the switch tube Q109, the other end of the capacitor C5, the other end of the capacitor C4, the pin 2 of the switch tube N4, the pin 2 of the switch tube N3, the pin 2 of the switch tube N2 and the port GND; the pin 4 of the transformer T1 is connected to the pin 1 of the switch tube Q128, the pin 2 of the switch tube Q128 is connected to one end of the capacitor C59 and the port OUT1, the pin 3 of the transformer T1 is connected to the other end of the capacitor C59 and the port AGND1, the pin 4 of the transformer T2 is connected to the pin 1 of the switch tube Q129, the pin 2 of the switch tube Q129 is connected to one end of the capacitor C22 and the port OUT2, and the pin 3 of the transformer T2 is connected to the other end of the capacitor C22 and the port AGND2.

[0008] A new three-phase energy storage converter topology is proposed to replace the traditional bidirectional inverter converter circuit, or the complex input inverter H-bridge circuit and LLC idea. Without reducing efficiency, it can achieve a wide battery voltage range and bus voltage range, thereby achieving high reliability, small size, and low cost for applications such as energy storage inverters, off-grid inverters, and grid-connected and off-grid inverters. The circuit consists of an inductor, an isolation capacitor, a transformer, and a power switch tube.

[0009] As a preferred improvement of the present invention: the port A is connected to one end of the inductor L13 through a fuse F7, the port B is connected to one end of the inductor L14 through a fuse F8, and the port C is connected to one end of the inductor L15 through a fuse F9.

[0010] As a preferred improvement of the present invention: the converter circuit topology includes a controller, which is connected to the control ends of switch tubes N1, N2, N3, N4, N5, N6, Q108 and Q109.

[0011] As a preferred improvement of the present invention: one end of the capacitor C15 is connected to one end of the capacitor C446, the other end of the capacitor C15 is connected to the other end of the capacitor C446, one end of the capacitor C17 is connected to one end of the capacitor C18, and the other end of the capacitor C17 is connected to the other end of the capacitor C18.

[0012] As a preferred improvement of the present invention: the port A, the port B and the port C are connected to three-phase electricity, and the port OUT1 and the port OUT2 are connected to a battery.

[0013] As a preferred improvement of the present invention: the port OUT1 is connected to the port OUT2, and the port AGND1 is connected to the port AGND2.

[0014] As a preferred improvement of the present invention: the switch tube Q128 and the switch tube Q129 are diodes, and the pin 1 of both is the positive end, and the pin 2 is the negative end.

[0015] As a preferred improvement of the present invention: the types of the switch tube N1, switch tube N2, switch tube N3, switch tube N4, switch tube N5, switch tube N6, switch tube Q108, switch tube Q109, switch tube Q128 and switch tube Q129 include but are not limited to IGBT, bipolar transistor, silicon carbide, gallium nitride and MOS tube.

[0016] As a preferred improvement of the present invention: the switch tube N1, switch tube N2, switch tube N3, switch tube N4, switch tube N5, switch tube N6, switch tube Q108, switch tube Q109, switch tube Q128 and switch tube Q129 are MOS tubes, wherein pin 1 is the drain and pin 2 is the source.

[0017] The beneficial effects of the present invention are as follows:

[0018] It can achieve stable bus voltage control and meet the performance requirements of various energy storage converters. In particular, the use of a single-stage circuit instead of a bridge circuit and high-voltage silicon carbide devices can achieve better reliability and higher efficiency, reduce costs, reduce size, and have the advantages of simplified circuit structure and software control. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0020] Figure 1 The present invention is a schematic diagram of a three-phase energy storage converter circuit topology. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention will be described clearly and completely below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0023] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0024] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0026] In some energy storage inverters, off-grid inverters and grid-connected and off-grid inverters, the working mode is generally when there is AC power, the power is taken from the grid to achieve the bus voltage, and then the battery is charged through bidirectional DC conversion; in the application of LLC+H bridge circuit, due to the two-stage conversion, it is very convenient to achieve control and adjustment, and the bus voltage can be stabilized, which is good for inverter output parallel connection and MPPT application, but the application cost is high and difficult to control; in the application of single-stage LLC bidirectional conversion, in order to achieve soft on and off control, the bus voltage is unstable, which has a great limitation on the performance of the inverter for charging, output parallel connection, grid-connected application, etc. within the battery voltage range, and various protections are prone to occur, resulting in ready-made defects or application problems. In view of the above description, a three-phase electric energy storage converter circuit is used to replace the single-stage LLC or LLC+H bridge circuit application, which can achieve stable bus voltage control and meet the performance needs of various energy storage converters; in particular, the use of a single-stage circuit to replace the bridge circuit and the use of high-voltage silicon carbide devices can achieve better reliability and higher efficiency, reduce costs, reduce size, simplify circuit structure and software control, etc.

[0027] See also Figure 1As shown, the present invention provides a three-phase energy storage converter circuit topology, including port A, port B and port C, wherein port A is connected to one end of an inductor L13, and the other end of the inductor L13 is connected to pin 2 of a switch tube N1 and pin 1 of a switch tube N2, port B is connected to one end of an inductor L14, and the other end of the inductor L14 is connected to pin 2 of a switch tube N5 and pin 1 of a switch tube N3, and port C is connected to one end of an inductor L15, and the other end of the inductor L15 is connected to pin 2 of a switch tube N6 and pin 1 of a switch tube N7. Pin 1 of the switch tube N4; Pin 1 of the switch tube N1 is connected to Pin 1 of the switch tube N5, Pin 1 of the switch tube N6, one end of the capacitor C3, one end of the capacitor C1 and one end of the inductor L1, the other end of the inductor L1 is connected to Pin 1 of the switch tube Q108 and one end of the capacitor C14, the other end of the capacitor C15 is connected to Pin 1 of the transformer T1, Pin 2 of the transformer T1 is connected to Pin 2 of the switch tube Q108 and port GND, the other end of the capacitor C3 is connected to the capacitor C1 The other end of the inductor L2 is connected to the pin 1 of the switch tube Q109 and one end of the capacitor C17, the other end of the capacitor C17 is connected to the pin 1 of the transformer T2, the pin 2 of the transformer T2 is connected to the pin 2 of the switch tube Q109, the other end of the capacitor C5, the other end of the capacitor C4, the pin 2 of the switch tube N4, the pin 2 of the switch tube N3, the pin 2 of the switch tube N2 and the port GND; Pin 4 of transformer T1 is connected to pin 1 of switch tube Q128, pin 2 of switch tube Q128 is connected to one end of capacitor C59 and port OUT1, pin 3 of transformer T1 is connected to the other end of capacitor C59 and port AGND1, pin 4 of transformer T2 is connected to pin 1 of switch tube Q129, pin 2 of switch tube Q129 is connected to one end of capacitor C22 and port OUT2, and pin 3 of transformer T2 is connected to the other end of capacitor C22 and port AGND2. Port OUT1 and port OUT2 can be connected to different devices, or the same device can be connected in series or in parallel. In this embodiment, port A is connected to one end of inductor L13 through fuse F7, port B is connected to one end of inductor L14 through fuse F8, and port C is connected to one end of inductor L15 through fuse F9. The converter circuit topology includes a controller, and the controller is connected to the control ends of the switch tubes N1, N2, N3, N4, N5, N6, Q108 and Q109. One end of the capacitor C15 is connected to one end of the capacitor C446, the other end of the capacitor C15 is connected to the other end of the capacitor C446, one end of the capacitor C17 is connected to one end of the capacitor C18, and the other end of the capacitor C17 is connected to the other end of the capacitor C18.The topology is simple, the number of components is small, the cost is low, and it can replace the expensive traditional inverter circuit structure and complete the bidirectional conversion of the energy storage inverter.

[0028] In the entire application, the high-voltage side of the circuit is connected to three-phase electricity, and the low-voltage side is connected to the battery. The three-phase electricity can also be replaced with other sources / loads. In this embodiment, the port A, the port B and the port C are connected to the three-phase electricity, and the port OUT1 and the port OUT2 are connected to the battery. Preferably, the port OUT1 and the port OUT2 are connected, the port AGND1 and the port AGND2 are connected, and the port OUT1 and the port OUT2 are connected in series with the battery. It should be further explained that the use of other components to achieve the above-mentioned effects should all fall within the inventive concept of the present invention and should fall within the protection scope of the present invention.

[0029] The circuit in the figure is a bidirectional energy storage inverter. When the circuit is applied to work unidirectionally, the primary or secondary MOS tube can be replaced with a diode. In this embodiment, the switch tube Q128 and the switch tube Q129 are diodes, and the pin 1 of the two is the positive terminal and the pin 2 is the negative terminal. It should be further explained that the use of other components to achieve the above effects should belong to the inventive concept of the present invention and should belong to the protection scope of the present invention.

[0030] The device used for switching in the figure is MOSFET, and other switching devices can also realize the function, including but not limited to IGBT, bipolar transistor, silicon carbide, gallium nitride. Specifically, the types of the switch tube N1, switch tube N2, switch tube N3, switch tube N4, switch tube N5, switch tube N6, switch tube Q108, switch tube Q109, switch tube Q128 and switch tube Q129 include but are not limited to IGBT, bipolar transistor, silicon carbide, gallium nitride and MOS tube. In this embodiment, the switch tube N1, switch tube N2, switch tube N3, switch tube N4, switch tube N5, switch tube N6, switch tube Q108, switch tube Q109, switch tube Q128 and switch tube Q129 are MOS tubes, wherein pin 1 is the drain and pin 2 is the source. It should be further explained that the use of other components to achieve the above-mentioned effects should all belong to the inventive concept of the present invention and should belong to the protection scope of the present invention.

[0031] Working principle:

[0032] When working in the forward direction (three-phase power input, output to charge the battery)

[0033] The three-phase voltage ABC at the input end is boosted through a three-phase six-switch circuit structure. The phases of each phase are staggered by 120°, and the boost is completed to store energy in large capacitors C1, C3, C4 and C5.

[0034] Q108 and Q128, Q109 and Q129 are complementary switches.

[0035] When Q108 is on, Q128 is off; when Q109 is on, Q129 is off. Inductor L1 stores energy through Q108, and inductor L2 stores energy through Q129. During this period, transformers T1 and T2, as well as capacitors C15, C446, C17, and C18 are reset.

[0036] When Q108 is turned off, Q128 is turned on, and the energy of inductor L1 is transferred to the battery side through capacitors C15, C446 and transformer T1.

[0037] When Q109 is turned off, Q129 is turned on, and the energy of inductor L2 is transferred to the battery side through capacitors C17, C18 and transformer T2.

[0038] When working in reverse direction (the battery is discharged at the output end, and the three-phase level is output at the forward input three-phase port)

[0039] When Q128 is turned on, Q108 is turned off, and the battery energy is transferred to the bus side through C446, C15 and L1, and L1 stores energy.

[0040] When Q129 is turned on, Q109 is turned off, and the battery energy is transferred to the bus side through C17, C18 and L2, and L2 stores energy.

[0041] When Q128 is turned off, Q108 is turned on, inductor L1 continues to flow, energy is released to the bus side, and C446, C15 and T1 are reset.

[0042] When Q129 is turned off, Q109 is turned on, the inductor L2 continues to flow, the energy is released to the bus side, and C17, C18 and T2 are reset.

[0043] During this period, the energy from the secondary is stored in the large capacitors C1, C3, C4 and C5. The energy of the large capacitors is output to the terminals through control based on the three-phase six switches.

[0044] A three-phase electric energy storage converter circuit is used to replace the single-stage LLC or LLC+H bridge circuit application, which can achieve stable bus voltage control and meet the performance requirements of various energy storage converters. In particular, the use of a single-stage circuit to replace the bridge circuit and the use of high-voltage silicon carbide devices can achieve better reliability and higher efficiency, reduce costs, reduce volume, simplify circuit structure and software control, etc.

[0045] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the embodiments. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A three-phase energy storage converter circuit topology, characterized in that: It includes port A, port B and port C, wherein port A is connected to one end of the inductor L13, the other end of the inductor L13 is connected to pin 2 of the switch tube N1 and pin 1 of the switch tube N2, port B is connected to one end of the inductor L14, the other end of the inductor L14 is connected to pin 2 of the switch tube N5 and pin 1 of the switch tube N3, port C is connected to one end of the inductor L15, the other end of the inductor L15 is connected to pin 2 of the switch tube N6 and pin 1 of the switch tube N4; The pin 1 of the switch tube N1 is connected to the pin 1 of the switch tube N5, the pin 1 of the switch tube N6, one end of the capacitor C3, one end of the capacitor C1 and one end of the inductor L1. The other end of the inductor L1 is connected to the pin 1 of the switch tube Q108 and one end of the capacitor C14. The other end of the capacitor C15 is connected to the pin 1 of the transformer T1. The pin 2 of the transformer T1 is connected to the pin 2 of the switch tube Q108 and the port GND. The other end of the capacitor C3 is connected to the other end of the capacitor C1, one end of the capacitor C4, one end of the capacitor C5 and one end of the inductor L2. The other end of the inductor L2 is connected to the pin 1 of the switch tube Q109 and one end of the capacitor C17. The other end of the capacitor C17 is connected to the pin 1 of the transformer T2. The pin 2 of the transformer T2 is connected to the pin 2 of the switch tube Q109, the other end of the capacitor C5, the other end of the capacitor C4, the pin 2 of the switch tube N4, the pin 2 of the switch tube N3, the pin 2 of the switch tube N2 and the port GND. Pin 4 of the transformer T1 is connected to pin 1 of the switch tube Q128, pin 2 of the switch tube Q128 is connected to one end of the capacitor C59 and port OUT1, pin 3 of the transformer T1 is connected to the other end of the capacitor C59 and port AGND1, pin 4 of the transformer T2 is connected to pin 1 of the switch tube Q129, pin 2 of the switch tube Q129 is connected to one end of the capacitor C22 and port OUT2, and pin 3 of the transformer T2 is connected to the other end of the capacitor C22 and port AGND2.

2. A three-phase energy storage converter circuit topology according to claim 1, characterized in that: The port A is connected to one end of the inductor L13 through a fuse F7, the port B is connected to one end of the inductor L14 through a fuse F8, and the port C is connected to one end of the inductor L15 through a fuse F9.

3. A three-phase energy storage converter circuit topology according to claim 1, characterized in that: The converter circuit topology includes a controller, which is connected to the control ends of the switch tube N1, the switch tube N2, the switch tube N3, the switch tube N4, the switch tube N5, the switch tube N6, the switch tube Q108 and the switch tube Q109.

4. A three-phase energy storage converter circuit topology according to claim 1, characterized in that: One end of the capacitor C15 is connected to one end of the capacitor C446, the other end of the capacitor C15 is connected to the other end of the capacitor C446, one end of the capacitor C17 is connected to one end of the capacitor C18, and the other end of the capacitor C17 is connected to the other end of the capacitor C18.

5. The three-phase energy storage converter circuit topology according to claim 1, characterized in that: The port A, the port B, and the port C are connected to three-phase electricity, and the port OUT1 and the port OUT2 are connected to a battery.

6. A three-phase energy storage converter circuit topology according to claim 1, characterized in that: The port OUT1 is connected to the port OUT2 , and the port AGND1 is connected to the port AGND2 .

7. A three-phase energy storage converter circuit topology according to claim 1, characterized in that: The switch tube Q128 and the switch tube Q129 are diodes, and pin 1 of the two is a positive end, and pin 2 is a negative end.

8. The three-phase energy storage converter circuit topology according to claim 1, characterized in that: The types of the switch tube N1, switch tube N2, switch tube N3, switch tube N4, switch tube N5, switch tube N6, switch tube Q108, switch tube Q109, switch tube Q128 and switch tube Q129 include but are not limited to IGBT, bipolar transistor, silicon carbide, gallium nitride and MOS tube.

9. A three-phase energy storage converter circuit topology according to claim 1, characterized in that: The switch tube N1, switch tube N2, switch tube N3, switch tube N4, switch tube N5, switch tube N6, switch tube Q108, switch tube Q109, switch tube Q128 and switch tube Q129 are MOS tubes, wherein pin 1 is a drain and pin 2 is a source.

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