A switching power supply and UPS

Abstract

A switching power supply and a UPS are disclosed to reduce the component cost and size of power supply equipment. The switching power supply includes multiple inductors, multiple bridge arms, a freewheeling branch, a bus capacitor, and a rectifier branch. Each inductor corresponds one-to-one with each bridge arm: the first end of each inductor is connected to the AC power supply, and the second end of each inductor is connected to the middle node of the corresponding bridge arm. The two ends of each bridge arm are connected to the bus capacitor via the freewheeling branch. The two ends of the rectifier branch are connected to the two ends of each bridge arm, and the middle node of the rectifier branch is connected to the middle node of the bus capacitor. Multiple PFC circuits within the switching power supply share a single rectifier branch and a freewheeling branch; only the parallel bridge arms and their connecting inductors are independent. Since it eliminates the need to configure separate freewheeling and rectifier branches for each PFC circuit, the component cost and size of the switching power supply can be effectively reduced.

Description

Technical Field

[0001] This application relates to the field of power supply technology, and in particular to a switching power supply and a UPS. Background Technology

[0002] A switching power supply is a type of power supply that maintains a stable output voltage by controlling the on and off time ratio of switching devices. It is widely used in various electronic devices, such as data centers, industrial control equipment, communication equipment, power equipment, instruments and meters, and security monitoring equipment, due to its small size, light weight and high efficiency.

[0003] In existing technologies, when switching power supplies are used in high-power power supply scenarios, multiple switching power supplies are typically connected in parallel to meet the power supply requirements of the load. For example, see... Figure 1 The diagram shows a switching power supply topology with power factor correction (PFC) functionality. This is used to improve the power supply capacity of devices, such as... Figure 2 As shown, two independent switching circuits can be directly connected in parallel. However, using this method increases the number of components in the device exponentially, increasing the cost and size of the power supply equipment. Utility Model Content

[0004] This application provides a switching power supply and a UPS for reducing the component cost and size of power supply equipment.

[0005] Firstly, embodiments of this application provide a switching power supply that can be connected between an AC power source and a load. The switching power supply converts AC power transmitted from an external AC power source into DC power and supplies power to the connected load. The switching power supply can be applied in various power supply scenarios, including data centers. The switching power supply may include multiple inductors, multiple bridge arms, freewheeling branches, bus capacitors, and rectifier branches. Each inductor corresponds one-to-one with each bridge arm.

[0006] Specifically, the first end of each inductor is connected to the AC power supply, and the second end of each inductor is connected to the middle node of the corresponding bridge arm; the two ends of each bridge arm are connected to the bus capacitor through the freewheeling branch; the two ends of the rectifier branch are connected to the two ends of each bridge arm, and the middle node of the rectifier branch is connected to the middle node of the bus capacitor.

[0007] By adopting a switching power supply structure, each bridge arm, the inductor connected to that bridge arm, the freewheeling branch, and the rectifier branch constitute a complete PFC branch. Multiple PFC circuits inside the switching power supply share a rectifier branch and a freewheeling branch. Only the parallel bridge arms and the inductors connected to each bridge arm are independent. Since there is no need to configure a freewheeling branch and a rectifier branch separately for each PFC circuit, the component cost and size of the switching power supply can be effectively reduced.

[0008] In one possible design, the freewheeling branch includes a first diode and a second diode.

[0009] Wherein, the anode of the first diode is connected to the first end of each bridge arm, and the cathode of the first diode is connected to the first end of the bus capacitor; the anode of the second diode is connected to the second end of the bus capacitor, and the cathode of the second diode is connected to the second end of each bridge arm.

[0010] In one possible design, the rectifier branch includes a third diode and a fourth diode.

[0011] The cathode of the third diode is connected to the first end of each bridge arm, the anode of the third diode is connected to the cathode of the fourth diode and the intermediate node N of the bus capacitor, and the anode of the fourth diode is connected to the second end of each bridge arm.

[0012] Using the above structure, during the positive half-cycle of the AC power supply, the first and fourth diodes, together with the bridge arm and inductor, can form a boost path between the AC power supply and the positive bus capacitor, charging the positive bus capacitor. During the negative half-cycle of the AC power supply, the second and third diodes, together with the bridge arm and inductor, can form a boost path between the AC power supply and the negative bus capacitor, charging the negative bus capacitor.

[0013] In one possible design, each bridge arm includes two switching transistors connected in series.

[0014] In one possible design, the bus capacitor includes a first capacitor and a second capacitor.

[0015] Wherein, the first end of the first capacitor constitutes the first end of the bus capacitor, and the second end of the first capacitor is connected to the first end of the second capacitor; the second end of the second capacitor constitutes the second end of the bus capacitor.

[0016] In one possible design, the switching power supply further includes a controller connected to the switching transistors in each bridge arm. The controller controls the switching transistors in each bridge arm to turn on and off by providing control signals of corresponding levels to each switching transistor, thereby controlling the operating state of the switching power supply.

[0017] One possible design may include two or more parallel bridge arms and two or more corresponding inductors.

[0018] In one possible design, the switches in each bridge arm operate in an interleaved parallel mode.

[0019] In one possible design, if the AC power supply is a three-phase AC power supply, the first end of each inductor is used to connect to one phase line of the AC power supply, and the number of inductors connected to each phase line of the AC power supply is the same.

[0020] Secondly, embodiments of this application provide a UPS that can be applied in a power device and is located between the AC power source and the load, and can use the electrical energy of the AC power source to provide stable power to the load. The UPS may include the aforementioned switching power supply, energy storage device, and inverter.

[0021] The switching power supply is connected to the energy storage device and the inverter, and is used to convert the AC power from the AC power source into DC power and supply power to the inverter and the energy storage device; the inverter is used to connect to the load, and is used to convert the DC power output by the switching power supply or the energy storage device into AC power and supply power to the load.

[0022] Furthermore, the technical effects of the second aspect and any of its possible designs can be found in the technical effects of different designs in the first aspect of the embodiments of this application, and will not be repeated here. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A schematic diagram of a switching power supply provided for related technologies Figure 1 ; Figure 2 A schematic diagram of a switching power supply provided for related technologies Figure 2 ; Figure 3 This application provides a schematic diagram of the structure of a switching power supply according to an embodiment of the present application. Figure 4 This is a schematic diagram of the structure of a bridge arm provided in an embodiment of this application; Figure 5 This is a schematic diagram of the structure of a follower branch provided in an embodiment of this application; Figure 6 A schematic diagram of a rectifier branch provided in an embodiment of this application; Figure 7 A schematic diagram of power transfer in a switching power supply provided in an embodiment of this application. Figure 1 ; Figure 8 A schematic diagram of power transfer in a switching power supply provided in an embodiment of this application. Figure 2 ; Figure 9 A schematic diagram of power transfer in a switching power supply provided in an embodiment of this application. Figure 3 ; Figure 10 A schematic diagram of power transfer in a switching power supply provided in an embodiment of this application. Figure 4 ; Figure 11 This is a schematic diagram of the structure of a UPS provided in an embodiment of this application. Detailed Implementation

[0025] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0026] The terminology used in the implementation section of this application is only for explaining specific embodiments of this application and is not intended to limit this application. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0027] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0028] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. The solutions provided in the embodiments of this application can be applied to medium and high power supply scenarios. Currently, the industry often uses parallel connection of PFC circuits with boost function to increase the output power of the switching power supply and meet the power supply requirements of the load connected to the downstream of the switching power supply.

[0029] In practical applications, each PFC circuit needs to be configured with a separate freewheeling and rectification path to meet the requirements of inductor energy storage and charging of the bus capacitor. If each independent PFC circuit is directly connected in parallel, it will increase the cost of the switching power supply components and also increase the size of the switching power supply.

[0030] Based on this, embodiments of this application provide a switching power supply and an uninterruptible power supply (UPS) to reduce the size and cost of the switching power supply.

[0031] The technical solution of this application can be summarized as follows: multiple PFC circuits inside the switching power supply share a single rectifier branch and a freewheeling branch, with only the parallel bridge arms and their connecting inductors being independent. Taking a single-phase AC power supply connected to the switching power supply as an example, the multiple PFC branches inside the switching power supply can share a single rectifier path and freewheeling path, eliminating the need for independent rectifier and freewheeling paths for each PFC branch. Furthermore, the output power of the switching power supply is the sum of the power of the multiple PFC branches. This effectively increases the power of the switching power supply while reducing the number of components, thereby reducing its size and cost.

[0032] like Figure 3 The diagram shown is a structural schematic of a switching power supply provided in an embodiment of this application. This switching power supply can be connected between an AC power source and a load, converting the AC power transmitted from the AC power source into DC power required to supply the load, and then supplying power to the load. See also... Figure 3 As shown, a switching power supply includes at least: multiple inductors, multiple bridge arms, a freewheeling branch, a bus capacitor, and a rectifier branch. Each inductor corresponds one-to-one with each bridge arm.

[0033] It should be understood that, Figure 3 The switching power supply structure shown is only an example. In practical applications, switching power supplies can have more advanced features than... Figure 1 The additional components shown, for example, the switching power supply may also include a voltage regulation circuit and a protection circuit. The voltage regulation circuit can convert the voltage amplitude of the bus capacitor into the supply voltage of the load, and the protection circuit can disconnect the connection to the load when the AC power supply or switching power supply fails, thereby preventing the fault from spreading further. Of course, the switching power supply may also include other functional devices, which are not limited in this application. Figure 3 The various components shown can be implemented in hardware, software, or a combination of hardware and software, including one or more signal processing and / or application-specific integrated circuits.

[0034] Specifically, the first end of each inductor is connected to the AC power supply, and the second end of each inductor is connected to the middle node of the corresponding bridge arm; the two ends of each bridge arm are connected to the bus capacitor through the freewheeling branch; the two ends of the rectifier branch are connected to the two ends of each bridge arm, and the middle node of the rectifier branch is connected to the middle node of the bus capacitor.

[0035] It should be noted that, Figure 3 This explanation uses an example where the bus capacitor consists of a first capacitor CP (positive bus) and a second capacitor CN (negative bus). The first terminal of the first capacitor CP forms the first terminal BUS+ of the bus capacitor, and the second terminal N of the first capacitor CP is connected to the first terminal of the second capacitor CN. The second terminal of the second capacitor CN forms the second terminal BUS- of the bus capacitor. In practical applications, the bus capacitor can consist of two or more capacitors; this application does not impose further limitations on this.

[0036] The switching power supply provided in this application embodiment shares a single rectifier branch and a freewheeling branch among multiple PFC circuits within it. Only the parallel bridge arms and the inductors connected to each bridge arm are independent. If the AC power supply connected to the switching power supply is a single-phase AC power supply, each bridge arm, the inductor connected to the bridge arm, and the shared rectifier and freewheeling branches can function as an independent PFC circuit to rectify the single-phase AC power output from the single-phase AC power supply. In this case, the total power of the switching power supply is the sum of the power of the multiple PFC circuits. If the AC power supply connected to the switching power supply is a three-phase AC power supply, multiple PFC circuits can be connected to each phase line transmitting the three-phase AC power. The three PFC branches connected to the three phase lines of the three-phase AC power supply constitute a three-phase PFC circuit to rectify the three-phase AC power. For ease of understanding, the following explanation uses a single-phase AC power supply as an example.

[0037] It should be noted that when the switching power supply is connected to a single-phase AC power source, multiple PFC branches can operate in an interleaved parallel mode. For example, when the switching power supply includes three PFC branches, the switching transistors in each PFC branch can operate with a 120° phase shift. The switching transistors in multiple PFC branches can also operate in the same state. Similarly, when the switching power supply is connected to a three-phase AC power source, multiple three-phase PFC circuits can operate in an interleaved parallel mode, or the switching transistors in multiple three-phase PFC branches can operate in the same state.

[0038] See Figure 3As shown, the rectifier branch can provide an energy storage path for the inductors in multiple PFC branches. During this stage, the electrical energy of the AC power supply can be stored in the inductors of the PFC branches. When the inductors have finished storing the energy, the multiple operating PFC branches can combine the electrical energy of the AC power supply and the energy stored in the inductors, and then output the combined energy through the freewheeling branch to charge the positive or negative bus capacitor. The boost voltage of the PFC branches can be adjusted by changing the duty cycle of the switching transistors in the PFC branches, which will not be discussed further in this application.

[0039] The following section, with reference to embodiments, details the structure of each circuit in the switching power supply and provides a detailed explanation of the working process of the switching power supply.

[0040] I. Bridge Arm

[0041] The middle node of each bridge arm is connected to the AC power supply via a corresponding inductor. Both ends of each bridge arm are connected to the bus capacitor via a freewheeling branch, and both ends of each bridge arm are also connected to the middle node of the bus capacitor via a rectifier branch. The middle node of the bus capacitor is also connected to the neutral line N of the AC power supply.

[0042] In practical applications, if the AC power supply is single-phase, the intermediate node of each bridge arm is connected to the live wire Lin of the single-phase AC power supply through the corresponding inductor. If the AC power supply is three-phase, the intermediate node of each bridge arm is connected to one of the phase lines transmitting the three-phase AC power through the corresponding inductor, and the number of bridge arms connected to each phase line of the three-phase AC power supply is the same.

[0043] In practical applications, each bridge arm can be composed of two switches connected in series, for example, see [link to example]. Figure 4 As shown, each bridge arm includes a first switch Q1 and a second switch Q2 connected in series. The first end of the first switch Q1 forms the first end of the bridge arm to which it belongs. The second end of the first switch Q1 is connected to the first end of the second switch Q2 and the second end of the inductor corresponding to the bridge arm to which it belongs. The second end of the second switch Q2 forms the second end of the bridge arm to which it belongs.

[0044] See Figure 4 As shown, if the AC power supply connected to the switching power supply is a single-phase AC power supply, then each bridge arm, the corresponding inductor, rectifier branch, and freewheeling branch can constitute a standard PFC circuit with boost function. Each PFC circuit can rectify the single-phase AC power output from the single-phase AC power supply. If the AC power supply connected to the switching power supply is a three-phase AC power supply, the three-phase AC power supply can be regarded as three single-phase AC power supplies, and the phase line of each phase AC power supply can also be connected to multiple of the above-mentioned PFC circuits.

[0045] It should be noted that, Figure 4The bridge arm shown uses an insulated gate bipolar transistor (IGBT) as an example only. In actual applications, other fully controlled switching transistors commonly used in the industry can also be used. This application will not list them all here.

[0046] In practical applications, since the conduction and turn-off of the fully controlled switching transistors are mainly controlled by the control signals received by the control terminals of the switching transistors, the switching power supply provided in this application embodiment can be connected to an external controller or the switching power supply can be configured with an internal controller. The controller can be connected to the control terminals of all switching transistors in the switching power supply and control the conduction and turn-off of the switching transistors by sending control signals of corresponding levels to the control terminals of the switching transistors, thereby controlling the working state of the switching power supply.

[0047] II. Rectifier Branch

[0048] The two ends of the rectifier branch are connected to the two ends of each bridge arm, and the middle node of the rectifier branch is connected to the middle node N of the bus capacitor. The rectifier branch can form an energy storage circuit for inductor L in each PFC circuit with the devices in the bridge arm. After the inductor L has stored enough energy, the energy stored in the inductor L can be superimposed with the energy of the AC power supply and output to the bus capacitor, thereby realizing the boost function of the switching power supply.

[0049] In one example, the rectifier branch may include a third diode D3 and a fourth diode D4. The cathode of the third diode D3 and the anode of the fourth diode D4 form the first terminal of the rectifier branch, and the anode of the third diode D3 and the cathode of the fourth diode D4 form the second terminal of the rectifier branch. See also... Figure 5 As shown, the cathode of the third diode D3 is connected to the first end of each bridge arm, and the anode of the third diode D3 is connected to the cathode of the fourth diode D4 and the intermediate node N of the bus capacitor. The anode of the fourth diode D4 is connected to the second end of each bridge arm.

[0050] See Figure 5 As shown, taking a single-phase AC power supply connected to a switching power supply as an example, the purpose of setting the third diode D3 is to provide an energy storage circuit for the inductor L in each PFC branch during the negative half-cycle of the single-phase AC power supply. The purpose of setting the fourth diode D4 is to provide an energy storage circuit for the inductor L in each PFC branch during the positive half-cycle of the single-phase AC power supply.

[0051] In practical implementation, during the positive half-cycle of the single-phase AC power supply, the second switch Q2 in the bridge arm can be turned on. At this time, the electrical energy of the single-phase AC power supply returns to the neutral line N of the single-phase AC power supply through inductor L, the second switch Q2, and the fourth diode D4. Therefore, the electrical energy of the single-phase AC power supply can be stored in the inductor L of the PFC branch through the path formed by inductor L, the second switch Q2, and the fourth diode D4. During the negative half-cycle of the single-phase AC power supply, the first switch Q1 in the bridge arm can be turned on. At this time, the electrical energy of the single-phase AC power supply can be stored in the inductor L of the PFC branch through the path formed by the third diode D3, the first switch Q1, and the inductor L.

[0052] It should be noted that the above description of the rectifier branch structure is only an example. In actual applications, the rectifier branch can use other commonly used devices with unidirectional conductivity, or the rectifier branch can use a switching transistor with a parasitic diode. This application does not impose any restrictions here.

[0053] III. Continuing Flow Branch

[0054] The freewheeling branch connects to each bridge arm and the bus capacitor. The two ports at the first end of the freewheeling branch connect to the two ends of each bridge arm, and the two ports at the second end connect to the two ends of the bus capacitor. The freewheeling branch forms a charging path between each PFC branch and the bus capacitor. Each PFC branch can combine the energy stored in its internal inductor with the energy from the AC power supply and output it to the bus capacitor through the freewheeling branch, thereby powering the load connected downstream of the bus capacitor.

[0055] In one example, the freewheeling branch may include a first diode D1 and a second diode D2. The anode of the first diode D1 and the cathode of the second diode D2 constitute the two interfaces of the first end of the freewheeling branch, and the cathode of the first diode D1 and the anode of the second diode D2 constitute the two interfaces of the second end of the freewheeling branch. See also... Figure 6 As shown, the anode of the first diode D1 is connected to the first end of each bridge arm, and the cathode of the first diode D1 is connected to the first end of the bus capacitor; the anode of the second diode D2 is connected to the second end of the bus capacitor, and the cathode of the second diode D2 is connected to the second end of each bridge arm.

[0056] See Figure 6 As shown, taking a single-phase AC power supply connected to a switching power supply as an example, the purpose of setting the first diode D1 is to charge the positive bus capacitor CP in the bus capacitor during the positive half-cycle of the single-phase AC power supply. The purpose of setting the second diode D2 is to charge the negative bus capacitor CN in the bus capacitor during the negative half-cycle of the single-phase AC power supply.

[0057] In practice, during the positive half-cycle of the single-phase AC power supply, when the inductor L in the PFC branch has finished storing energy, the first switch Q1 in the bridge arm or its parasitic diode can be turned on. The energy stored in inductor L and the energy transmitted by the single-phase AC power supply are superimposed and transmitted to the first capacitor CP through the first diode D1, and then to the neutral line N of the AC power supply. During the negative half-cycle of the single-phase AC power supply, when the inductor in the PFC branch has finished storing energy, the second switch Q2 in the bridge arm or its parasitic diode can be turned on. The energy stored in inductor L and the energy transmitted by the AC power supply are superimposed and transmitted to the second capacitor CN through the first diode D2, and then to the live wire Lin of the AC power supply.

[0058] It should be noted that the above description of the freewheeling branch structure is only an example. In actual applications, the freewheeling branch can use other commonly used devices with unidirectional conductivity, or the freewheeling branch can use a switching transistor with a parasitic diode. This application does not impose any restrictions here.

[0059] The following is combined with Figure 6 The structure of the switching power supply is shown, and the process of the switching power supply outputting AC power is described in detail.

[0060] See Figure 6 As shown, taking the AC power supply connected to a switching power supply as an example, and using the operation of one of the PFC branches as an example, for the positive half-cycle of a single-phase AC power supply, see [reference needed]. Figure 7 As shown, the second switch Q2 in the bridge arm can be turned on. At this time, the electrical energy from the single-phase AC power supply is stored in inductor L through the path formed by inductor L, the second switch Q2, and the fourth diode D4. When Q2 is turned off, see... Figure 8 As shown, the electrical energy stored in the inductor L and the electrical energy of the single-phase AC power supply can be superimposed and then output to the positive bus capacitor CP in the bus capacitor through the parasitic diode of the first switching transistor Q1 and the first diode D1, thereby realizing the boost function of the switching power supply.

[0061] See also Figure 6 As shown, for the negative half-cycle of a single-phase AC power supply, see [reference needed]. Figure 9 As shown, the first switch Q1 in the bridge arm can be turned on. At this time, the electrical energy from the single-phase AC power supply is stored in inductor L through the path formed by the third diode D3, the first switch Q1, and the inductor L. When Q1 is turned off, see... Figure 10As shown, the electrical energy stored in inductor L and the electrical energy from the single-phase AC power supply can be superimposed and then used to charge the negative bus capacitor CN through the path formed by the negative bus capacitor CN, the second diode D2, and the parasitic diode of the second switching transistor Q2. Since the two capacitors in the bus capacitor are charged during the positive and negative half-cycles of the AC power supply, voltage balance of the bus capacitors can be achieved, ensuring the normal operation of the switching power supply.

[0062] In practical applications, all components of a switching power supply can be housed in a single device with multiple external interfaces on its casing. AC power and loads can be connected to the switching power supply through these interfaces. In this case, the switching power supply can be considered a device independent of both the load and the power supply itself. Alternatively, all components of the switching power supply can be housed within the load in a single device with external interfaces on its casing. AC power can be connected to the switching power supply through these interfaces. In this case, the switching power supply can be considered a component within the device containing the load.

[0063] Based on the above description, this application also provides a UPS, which can be connected between an AC power source and a load, and can provide a stable power supply voltage to the connected load. See also Figure 11 As shown, a UPS may include the aforementioned switching power supply, energy storage device, and inverter.

[0064] It should be noted that, Figure 11 The UPS structure shown is only an example. In actual applications, the UPS may also include other functional circuits. For example, the UPS may also include surge protection devices and protection circuits. Of course, the UPS may also include other functional circuits, but this application does not impose any restrictions on them.

[0065] Among them, see Figure 11 As shown, the switching power supply is connected to the energy storage device and the inverter to convert the AC power from the AC power source into DC power and to supply power to the inverter and the energy storage device; the inverter is connected to the load to convert the DC power output from the switching power supply or the energy storage device into AC power and to supply power to the load.

[0066] It should be noted that the inverter can also adopt the industry-standard circuit topology with inverter function, such as the NPC circuit structure. Of course, the inverter can also adopt other circuit topologies, which will not be described in detail here.

[0067] In one example, the energy storage device may include a battery module and a battery charging / discharging circuit. The battery module is connected to the bus capacitor of the switching power supply via the battery charging / discharging circuit. When the AC power supply connected to the switching power supply is normal, the switching power supply can convert the AC power output from the AC power supply into DC power and supply power to the inverter and the energy storage device. The inverter converts the DC power into AC power required to supply power to the load and supplies power to the load. The battery charging / discharging circuit in the energy storage device charges the battery module after regulating the voltage of the DC power. When the AC power supply connected to the switching power supply fails, the battery charging / discharging circuit of the energy storage device can use the energy stored in the battery module to supply power to the bus capacitor. The inverter converts the DC power on the bus capacitor into AC power required to supply power to the load and supplies power to the load.

[0068] In another example, the energy storage device may include a battery module, a switching module, and a battery charging circuit. The battery module is connected to the input of a switching power supply via the switching module, and is also connected to the bus capacitor of the switching power supply via the battery charging circuit. When the AC power supply connected to the switching power supply is normal, the battery charging circuit in the energy storage device regulates the DC power on the bus capacitor and charges the battery module. When the AC power supply connected to the switching power supply fails, the switching module in the energy storage device closes, and the energy stored in the battery module is processed by the switching power supply to power the bus capacitor. The inverter converts the DC power on the bus capacitor into the AC power required to power the load and supplies power to the load. That is, the discharge circuit of the battery module is multiplexed with some components in the switching power supply, thereby reducing the size and cost of the energy storage device.

[0069] In practical applications, all components of a UPS can be integrated into a single cabinet. The cabinet is equipped with power interfaces and load structures. AC power can be connected to the UPS through the power interface, and the load can be connected to the UPS through the load interface.

[0070] In the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions of different embodiments are consistent and can be referenced by each other. The technical features of different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0071] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the scope of protection of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A switching power supply, characterized in that, include: Multiple inductors, multiple bridge arms, freewheeling branches, bus capacitors, and rectifier branches; each inductor corresponds one-to-one with each bridge arm: The first end of each inductor is used to connect to the AC power supply, and the second end of each inductor is connected to the middle node of the corresponding bridge arm. Both ends of each bridge arm are connected to the bus capacitor through the freewheeling branch; The two ends of the rectifier branch are connected to the two ends of each bridge arm, and the middle node of the rectifier branch is connected to the middle node of the bus capacitor.

2. The switching power supply according to claim 1, characterized in that, The freewheeling branch includes: a first diode and a second diode; The anode of the first diode is connected to the first end of each bridge arm, and the cathode of the first diode is connected to the first end of the bus capacitor. The anode of the second diode is connected to the second terminal of the bus capacitor, and the cathode of the second diode is connected to the second terminal of each bridge arm.

3. The switching power supply according to claim 2, characterized in that, The rectifier branch includes: a third diode and a fourth diode; The cathode of the third diode is connected to the first end of each bridge arm, and the anode of the third diode is connected to the cathode of the fourth diode and the intermediate node of the bus capacitor. The anode of the fourth diode is connected to the second end of each bridge arm.

4. The switching power supply according to claim 3, characterized in that, Each bridge arm includes two switching transistors connected in series.

5. The switching power supply according to claim 1, characterized in that, The bus capacitor includes a first capacitor and a second capacitor; The first terminal of the first capacitor constitutes the first terminal of the bus capacitor, and the second terminal of the first capacitor is connected to the first terminal of the second capacitor. The second terminal of the second capacitor constitutes the second terminal of the bus capacitor.

6. The switching power supply according to claim 4, characterized in that, The switching power supply also includes a controller, which is connected to the switching transistor in each bridge arm and is used to control the switching transistor in each bridge arm to turn on and off.

7. The switching power supply according to claim 4, characterized in that, The switches in each bridge arm operate in an interleaved parallel mode.

8. The switching power supply according to claim 1, characterized in that, If the AC power supply is a three-phase AC power supply, the first end of each inductor is used to connect to one phase line of the AC power supply, and the number of inductors connected to each phase line of the AC power supply is the same.

9. A UPS, characterized in that, Includes the switching power supply, energy storage device, and inverter as described in any one of claims 1 to 8; The switching power supply is connected to the energy storage device and the inverter, and is used to convert the AC power of the AC power supply into DC power and to supply power to the inverter and the energy storage device. The inverter is used to connect to the load and convert the DC power output by the switching power supply or the energy storage device into AC power to supply power to the load.

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