A switching power supply and UPS

Abstract

A switching power supply and a UPS are disclosed to reduce the cost of the switching power supply and to enable dual power input. The switching power supply includes multiple inductors, a first switching module, multiple bridge arms, a freewheeling branch, a bus capacitor, a rectifier branch, and a second switching module. Each inductor and each bridge arm corresponds one-to-one: the first end of each inductor is connected to an AC power source through the first switching module, and the second end 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; both ends of the rectifier branch are connected to both ends of each bridge arm, and the middle node is connected to the middle node of the bus capacitor; the second switching module is connected to two of the multiple inductors and to a battery module. Each inductor, the bridge arm connected to it, the freewheeling branch, and the rectifier branch constitute a PFC circuit. Multiple PFC circuits share the freewheeling branch and the rectifier branch, and the first and second switching modules enable dual power input for the switching power supply.

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, switching power supplies generally employ a power factor correction (PFC) circuit topology. When a switching power supply is used in a high-power supply scenario, multiple PFC circuits are typically connected in parallel to increase the power of the switching power supply. To reduce the number of components and the size of the switching power supply, a scheme has been proposed to reuse some components of some PFC circuits. There is an urgent need for a component reuse circuit topology and a dual-power supply connection scheme under this circuit topology. Utility Model Content

[0004] This application provides a switching power supply and a UPS for reducing the component cost and size of the switching power supply, and for realizing a dual-power supply design for the switching power supply.

[0005] In a first aspect, 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 can utilize the AC power source or electrical energy stored in a battery module to power 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, a first switching module, multiple bridge arms, a freewheeling branch, a bus capacitor, a rectifier branch, and a second switching module; wherein 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 battery module through the first switching module, 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; both ends of the rectifier branch are connected to both ends of each bridge arm, and the middle node of the rectifier branch is connected to the middle node of the bus capacitor; the second switching module is connected to two of the plurality of inductors. The second switching module is also connected to the battery module.

[0007] Using the above-described switching power supply structure, each inductor, the bridge arm connected to that inductor, the rectifier branch, and the freewheeling branch constitute a PFC branch with boost function. Multiple PFC branches share a single freewheeling and rectifier branch. Since there is no need to configure a separate freewheeling branch for each PFC circuit, the component cost and size of the switching power supply can be effectively reduced. Furthermore, the input terminal of the PFC branch can be connected to an AC power supply through a first switching module, and also to a battery module through a second switching module, thus achieving dual power supply input for the switching power supply. When the AC power supply is normal, its energy can be used to power the load. When the AC power supply fails, the energy stored in the battery module can be used to power the load, thereby improving the power supply stability of the switching power supply.

[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 of the bus capacitor, and the anode of the fourth diode is connected to the second end of each bridge arm.

[0012] With the above structure, when the AC power supply is normal, during the positive half-cycle of the AC power supply, the first diode, the fourth diode, the bridge arm, and the inductor can form a boost path between the AC power supply and the positive bus capacitor. During the negative half-cycle of the AC power supply, the second diode, the third diode, the bridge arm, and the inductor can form a boost path between the AC power supply and the negative bus capacitor.

[0013] 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.

[0014] 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 through the first switching module, and the number of inductors connected to each phase line of the AC power supply is the same.

[0015] In one possible design, the first switch module includes multiple first switches, each connected to an inductor in a one-to-one correspondence. With this design, each inductor is connected to the AC power supply via an independent first switch, and the electrical connection to the AC power supply is controlled by this first switch.

[0016] In one possible design, if the battery module includes a positive battery module and a negative battery module, the second switch module includes a second switch and a third switch.

[0017] The first end of the second switch is connected to one of the multiple inductors, and the second end of the second switch is connected to the positive terminal of the positive battery module; the second end of the third switch is connected to the other inductor of the multiple inductors, and the second end of the third switch is connected to the negative terminal of the negative battery module.

[0018] In one possible design, if the battery module includes a positive battery module, the second switch module includes a fourth switch, the first end of the fourth switch is connected to one of the inductors of the plurality of inductors, the second end of the fourth switch is connected to the positive terminal of the positive battery module, wherein the negative terminal of the positive battery module is connected to another inductor of the plurality of inductors.

[0019] In one possible design, the switching power supply further includes a battery charging circuit connected between the bus capacitor and the battery module.

[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 of the AC power supply 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 This application provides a schematic diagram of the structure of a switching power supply according to an embodiment of the present application. Figure 2 This is a schematic diagram of the structure of a bridge arm provided in an embodiment of this application; Figure 3 A schematic diagram of a rectifier branch provided in an embodiment of this application; Figure 4 This is a schematic diagram of the structure of a follower branch provided in an embodiment of this application; Figure 5 This is a schematic diagram of the structure of a first switch module provided in an embodiment of this application; Figure 6 A schematic diagram of the structure of a second switch module provided in this application embodiment. Figure 1 ; Figure 7 A schematic diagram of the structure of a second switch module provided in this application embodiment. Figure 2 ; Figure 8 A schematic diagram of power transfer in an AC power supply mode provided in this application embodiment. Figure 1 ; Figure 9 A schematic diagram of power transfer in an AC power supply mode provided in this application embodiment. Figure 2 ; Figure 10 A schematic diagram of power transfer in an AC power supply mode provided in this application embodiment. Figure 3 ; Figure 11 A schematic diagram of power transfer in an AC power supply mode provided in this application embodiment. Figure 4 ; Figure 12 A schematic diagram of power transfer in a battery module power supply mode provided in this application embodiment. Figure 1 ; Figure 13 A schematic diagram of power transfer in a battery module power supply mode provided in this application embodiment. Figure 2 ; Figure 14 A schematic diagram of power transfer in a battery module power supply mode provided in this application embodiment. Figure 3 ; Figure 15 A schematic diagram of power transfer in a battery module power supply mode provided in this application embodiment. Figure 4 ; Figure 16 A schematic diagram of power transfer in a battery module power supply mode provided in this application embodiment. Figure 5 ; Figure 17 A schematic diagram of power transfer in a battery module power supply mode provided in this application embodiment. Figure 6 ; Figure 18 A schematic diagram of power transfer in a battery module power supply mode provided in this application embodiment. Figure 7 ; Figure 19 A schematic diagram of power transfer in a battery module power supply mode provided in this application embodiment. Figure 8 . 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. The switching power supply can be connected between the AC power supply and the load to convert the electrical energy of the AC power supply into the power supply energy of the load and supply power to the load.

[0029] The technical solution of this application can be summarized as follows: Each bridge arm inside the switching power supply, along with the inductor, freewheeling branch, and rectifier branch connected to that bridge arm, can constitute a PFC circuit with boost function. Multiple PFC circuits inside the switching power supply can share a single freewheeling branch and rectifier branch. Only the parallel bridge arms and the inductors connected to each bridge arm are independent. Since it is not necessary to configure separate freewheeling and rectifier branches for each PFC circuit, the number of components in the switching power supply can be effectively reduced, thereby reducing the size and cost of the switching power supply. In addition, the input terminal of each PFC branch can be connected to an AC power supply through a first switching module, and the input terminals of two PFC branches can be connected to a battery module through a second switching module, thereby realizing dual power input for the switching power supply and improving the power supply stability of the switching power supply.

[0030] like Figure 1 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, and also between a battery module and a load. When the AC power source is normal, the switching power supply can convert the AC power transmitted from the AC power source into DC power required to power the load, and then supply power to the load. When the AC power source fails, the switching power supply can also utilize the electrical energy stored in the battery module to power the load. See also... Figure 1 As shown, a switching power supply includes at least: multiple inductors, a first switching module, multiple bridge arms, a freewheeling branch, a bus capacitor, a rectifier branch, and a second switching module. Each inductor corresponds one-to-one with each bridge arm.

[0031] It should be understood that, Figure 1 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 1 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.

[0032] Specifically, the first end of each inductor is connected to the AC power supply through the first switching module, 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; the second switching module is connected to two of the multiple inductors, and the second switching module is used to connect to the battery module.

[0033] It should be noted that, Figure 1 This explanation uses an example where the bus capacitor consists of a positive bus capacitor CP and a negative bus capacitor CN. The first terminal of the positive bus capacitor CP forms the first terminal BUS+ of the bus capacitor, and the second terminal of the positive bus capacitor CP is connected to the first terminal of the negative bus capacitor CN. The second terminal of the negative bus capacitor CN forms the second terminal BUS- of the bus capacitor. In practical applications, the bus capacitor can consist of two or more capacitors, and this application does not impose any restrictions on this.

[0034] The switching power supply provided in this application embodiment shares a single rectifier branch and a freewheeling branch within its internal switching circuit. Only the parallel bridge arms and the inductors connected to them are independent. If the AC power supply is single-phase, a single PFC branch can function as an independent PFC circuit to rectify the single-phase AC power output. 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 three-phase, the three PFC branches are connected to the three phase lines of the three-phase AC power supply via the first switching module. The three PFC branches function as an independent three-phase PFC circuit to rectify the three-phase AC power output. In this case, the total power of the switching power supply is the sum of the power of the multiple three-phase PFC circuits. When the AC power supply fails, the two PFC branches connected to the second switching module form a Boost circuit, which boosts the voltage of the battery module and outputs it to the bus capacitor, supplying power to the load connected to the downstream of the bus capacitor. To facilitate understanding, the following explanation will use the example of a switching power supply connected to a single-phase AC power supply.

[0035] It should be noted that when the AC power supply is single-phase and normal, 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 operating states of the switching transistors in multiple PFC branches can also be the same. Similarly, when the AC power supply is three-phase and normal, multiple three-phase PFC circuits can operate in an interleaved parallel mode, and the operating states of the switching transistors in multiple three-phase PFC circuits can also be controlled to be the same.

[0036] See Figure 1As shown, the rectifier branch can provide an energy storage path for the inductors in multiple PFC circuits, storing the AC power supply's energy in the inductors of the PFC circuits. When the inductors are fully stored, the multiple operating PFC circuits can combine the AC power supply's energy or the energy stored in the battery module with the energy stored in the inductors and output the combined energy to charge the positive or negative bus capacitor. The boost voltage of the PFC circuit can be adjusted by changing the duty cycle of the switching transistors in the PFC circuit, which will not be discussed further in this application.

[0037] 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.

[0038] I. Bridge Arm

[0039] The middle node of each bridge arm is connected to the AC power supply via a corresponding inductor and the first switching module. 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.

[0040] 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 and the first switching module. 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 is the same.

[0041] In practical applications, each bridge arm can consist 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.

[0042] See Figure 2As shown, if the AC power supply connected to the switching power supply is a single-phase AC power supply, then each bridge arm, its corresponding inductor, freewheeling branch, and rectifier 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, then each bridge arm, its corresponding inductor, freewheeling branch, and rectifier branch can constitute a standard PFC branch with boost function. Three PFC branches constitute a complete three-phase PFC circuit, which can rectify the three-phase AC power. To increase the power of the switching power supply, it contains multiple three-phase PFC circuits; that is, each phase line of the three-phase AC power supply is connected to multiple PFC branches, and the number of PFC branches connected to each phase line is the same.

[0043] It should be noted that, Figure 2 The 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.

[0044] 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.

[0045] II. Rectifier Branch

[0046] 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, together with the bridge arms and the inductors connected to the bridge arms, forms the energy storage circuit for inductor L in each PFC circuit. When the voltage of the AC power supply is less than the voltage of the bus capacitor, the electrical energy of the AC power supply can be stored in the inductor L in each PFC branch during this period, thus avoiding energy waste. After the inductor L has finished storing energy, the energy stored in the inductor L can be superimposed with the electrical energy of the AC power supply and output to the bus capacitor, thereby realizing the boost function of the switching power supply and improving the efficiency of the switching power supply.

[0047] 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 3 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.

[0048] See Figure 3 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 circuit 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 circuit during the positive half-cycle of the single-phase AC power supply.

[0049] 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 the inductor, the second switch, and the fourth diode D4. The electrical energy of the single-phase AC power supply can also be stored in the inductor L of the PFC circuit through the path formed by the 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 circuit through the path formed by the third diode D3, the first switch Q1, and the inductor L.

[0050] 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.

[0051] III. Continuing Flow Branch

[0052] The freewheeling branch connects the bridge arm and the bus capacitor. The two interfaces at the first end of the freewheeling branch are connected to the two ends of each bridge arm, and the two interfaces at the second end of the freewheeling branch are connected to the two ends of the bus capacitor. The freewheeling branch can form a charging path between each PFC circuit and the bus capacitor. Each PFC circuit can combine the electrical energy stored in its internal inductor and the electrical energy from the AC power supply and output it to the bus capacitor through the freewheeling branch, thereby supplying power to the load connected to the back end of the bus capacitor.

[0053] 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 4As 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.

[0054] See Figure 4 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.

[0055] In practical implementation, during the positive half-cycle of the single-phase AC power supply, when the inductor L in the PFC circuit 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 positive bus 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 circuit 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 negative bus capacitor CN through the first diode D2, and then to the live wire Lin of the AC power supply.

[0056] 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.

[0057] IV. First Switch Module

[0058] The first switching module is connected between the AC power supply and each inductor, used to control the electrical connection between the AC power supply and each PFC circuit. When the AC power supply is normal, it can control the connection between the AC power supply and each PFC circuit. Each PFC circuit can receive AC power from the AC power supply, rectify and boost the received AC power, and then output it to the bus capacitor, thereby powering the load connected downstream of the bus capacitor. When the AC power supply fails, it can disconnect the connection between the AC power supply and each PFC circuit, thus preventing the fault from spreading further.

[0059] In some implementations, the first switch module includes a plurality of first switches, each of which is connected to each inductor in a one-to-one correspondence.

[0060] See one example. Figure 5As shown, if the AC power supply is a single-phase AC power supply, the first switch module includes a first switch K1. The first end of the first switch K1 is connected to the live wire Lin of the single-phase AC power supply, and the second end of the first switch K1 is connected to the first end of each inductor L.

[0061] In another example, if the AC power supply is a three-phase AC power supply, the first switch module includes multiple first switches K1. The three PFC branches in the three-phase PFC circuit are respectively connected to one phase line of the three-phase AC power supply through a first switch K1, and the number of inductors connected to each phase line of the AC power supply is the same.

[0062] V. Second Switch Module

[0063] The second switching module is connected between the battery module and the two inductors, and is used to control the connection between the battery module and the two PFC branches. The first and second switching modules enable dual power input switching of the switching power supply. For example, when the AC power supply is normal, the second switching module can disconnect the battery module from the two PFC branches, allowing the AC power supply to power the load. When the AC power supply fails, the first switching module disconnects the battery module from the AC power supply, connecting the battery module to the two PFC branches and powering the load. In this case, the two PFC branches form a Boost circuit, and the battery module's voltage is boosted and output to the bus capacitor, thereby powering the load connected downstream of the bus capacitor.

[0064] It should be noted that the embodiments in this application are illustrated using an external battery module for a switching power supply as an example. In actual applications, a battery module can also be configured inside the switching power supply.

[0065] In some embodiments, if the battery module includes a positive battery module Bat1 and a negative battery module Bat2, see [reference needed]. Figure 6 As shown, the second switch module includes a second switch K2 and a third switch K3.

[0066] Specifically, the first terminal of the second switch K2 is connected to one of the multiple inductors, and the second terminal of the second switch K2 is connected to the positive terminal of the positive battery module Bat1. The second terminal of the third switch K3 is connected to the other inductor among the multiple inductors, and the second terminal of the third switch K3 is connected to the negative terminal of the negative battery module Bat2.

[0067] In some implementations, if the battery module includes a positive battery module Bat1, see [link to relevant documentation]. Figure 7 As shown, the second switch module includes a fourth switch K4. The first terminal of the fourth switch K4 is connected to one of the multiple inductors, and the second terminal of the fourth switch K4 is connected to the positive terminal of the positive battery module Bat1. The negative terminal of the positive battery module Bat1 is connected to another inductor among the multiple inductors.

[0068] The following is combined 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.

[0069] See Figure 6 As shown, taking a single-phase AC power supply and the operation of one of the PFC branches as an example, when the AC power supply is normal, the first switch K1 is closed. For the positive half-cycle of the single-phase AC power supply, see [link to relevant documentation]. Figure 8 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 9 As shown, the electrical energy stored in the inductor L and the electrical energy from the single-phase AC power supply can be superimposed and 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. Since this part of the electrical energy is composed of the electrical energy stored in the inductor and the electrical energy from the single-phase AC power supply, it can still charge the bus capacitor even when the peak value of the single-phase AC power supply is less than the bus capacitor voltage, thus realizing the boost function of the switching power supply.

[0070] See Figure 6 As shown, for the negative half-cycle of a single-phase AC power supply, see [reference needed]. Figure 10 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 11 As 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.

[0071] See Figure 6 As shown, when the AC power supply fails, the second switch K2 and the third switch K3 are closed. Taking the positive battery module Bat1 as an example, see [link to example]. Figure 12 As shown, when the second switch Q2 in the left bridge arm is closed, the electrical energy of the positive battery module Bat1 flows from its positive terminal through inductor L, the second switch Q2, and the fourth diode D4 back to its negative terminal. The electrical energy of the positive battery module Bat1 can be stored in the inductor L connected to the second switch K2 via the above path. (See also...) Figure 13As shown, when the first switch Q1 in the right bridge arm is closed, the electrical energy of the negative battery module Bat2 can return from the positive terminal of the negative battery module Bat2 through the third diode D3, the first switch Q1 and the inductor L to the negative terminal of the negative battery module Bat2. The electrical energy of the negative battery module Bat2 can be stored in the inductor L connected to the third switch K3 through the above path.

[0072] See also Figure 6 As shown, when the second switch Q2 in the left bridge arm or the first switch Q1 in the right bridge arm is disconnected, the inductor L connected to the second switch K2 and the third switch K3 has completed energy storage. (See also...) Figure 14 As shown, the electrical energy of the positive battery module, combined with the electrical energy stored in the inductor L connected to the second switch K2, charges the positive bus capacitor CP through the path formed by the second switch K2, inductor L, the parasitic diode of the first switch Q1, and the first diode D1. (See also...) Figure 15 As shown, the electrical energy of the negative battery module and the electrical energy stored in the inductor L connected to the third switch K3 are superimposed and then charged through the path formed by the third switch K3, the negative bus capacitor CN, the second diode D2, the parasitic diode of the second switch Q2 and the inductor L.

[0073] The following is combined Figure 7 The structure of the switching power supply is shown, and the power supply process of the battery module to the switching power supply is described in detail.

[0074] See Figure 7 As shown, when the AC power supply fails, the fourth switch K4 is closed. (See below) Figure 16 As shown, when the first switch Q1 in the right bridge arm is closed, the electrical energy of the positive battery module Bat1 returns from the positive terminal of Bat1 through the fourth switch K4, inductor L, the parasitic diode of the first switch Q1 in the left bridge arm, the first switch Q1 in the right bridge arm, and inductor L to the negative terminal of the positive battery module. The electrical energy of the positive battery module Bat1 can be stored in the inductors of the two PFC circuits through the above path.

[0075] In practical applications, other paths can be used for energy storage in inductor L, for example, see [link to relevant documentation]. Figure 17 As shown, when the second switch Q2 in the left bridge arm is closed, the electrical energy of the positive battery module Bat1 flows from its positive terminal through the fourth switch K4, inductor L, the second switch Q2 in the left bridge arm, the parasitic diode of the second switch Q2 in the right bridge arm, and inductor L back to the negative terminal of the positive battery module. The electrical energy of the positive battery module Bat1 can be stored in the inductors of the two PFC branches via this path. See also... Figure 18 As shown, the two paths mentioned above can also be used together to store energy in inductor L.

[0076] See also Figure 7 As shown, when the first switch Q1 in the right bridge arm and the second switch Q2 in the left bridge arm are disconnected, the inductors L in the two PFC branches have completed energy storage. (See also...) Figure 19 As shown, the electrical energy of the positive battery module is superimposed with the electrical energy stored in the inductors of the two PFC circuits, and then output to the positive bus capacitor CP and the negative bus capacitor CN through the path formed by the fourth switch K4, the parasitic diode of the first switch Q1, the first diode D1, the positive bus capacitor CP, the negative bus capacitor CN, the second diode D2, the parasitic diode of the second switch Q2 in another PFC branch and the inductor L.

[0077] In practical applications, to ensure that the battery module has sufficient power to supply the load when the AC power supply fails, the switching power supply provided in this application embodiment may further include a battery charging circuit or an external battery charging circuit. This battery charging circuit can be connected between the bus capacitor and the battery module. When the AC power supply is normal, the battery charging circuit can obtain voltage from the bus capacitor, convert the bus capacitor voltage into the charging voltage of the battery module, and charge the battery module.

[0078] 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.

[0079] 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. The UPS may include the aforementioned switching power supply, energy storage device, and inverter.

[0080] It should be noted that in practical applications, UPS may also include other functional circuits. For example, UPS may also include surge protection devices and protection circuits. Of course, UPS may also include other functional circuits, which are not limited in this application.

[0081] The switching power supply is connected to the energy storage device and the inverter to convert AC power into DC power and supply power to the inverter and the energy storage device. The inverter is connected to the load to convert DC power output from the switching power supply or the energy storage device into AC power and supply power to the load.

[0082] It should be noted that the inverter can also adopt the industry-standard circuit topology with inverter function, such as the Vienna circuit structure. Of course, the inverter can also adopt other circuit topologies, which will not be described in detail here.

[0083] In one example, if the switching power supply does not have an internal battery charging circuit, the energy storage device may include a battery module and a battery charging circuit. The battery module is 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 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 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 energy stored in the battery module can be transferred to the bus capacitor of the switching power supply through a second switching module. 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.

[0084] In another example, if the switching power supply has an internal battery charging circuit, the energy storage device may include a battery module. The battery module is connected to two PFC branches via a second switching module and to the bus capacitor via the internal battery charging circuit of the switching power supply. When the AC power supply connected to the switching power supply is normal, the battery charging circuit regulates the DC power on the bus capacitor and charges the battery module. When the AC power supply fails, the switch in the second switching module closes, and the energy stored in the battery module powers the bus capacitor through the Boost circuit formed by the second switching module and the two PFC branches. The inverter converts the DC power on the bus capacitor into AC power required to power the load and supplies power to the load.

[0085] 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.

[0086] 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.

[0087] 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: The system includes multiple inductors, a first switching module, multiple bridge arms, a freewheeling branch, a bus capacitor, a rectifier branch, and a second switching module; each inductor corresponds one-to-one with each bridge arm. The first end of each inductor is connected to the AC power supply through the first switch module, 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. The second switch module is connected to two of the plurality of inductors, and the second switch module is used to connect to the battery module.

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 1, 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.

5. 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 through the first switch module, and the number of inductors connected to each phase line of the AC power supply is the same.

6. The switching power supply according to claim 1, characterized in that, The first switch module includes multiple first switches, and each first switch is connected to each inductor in a one-to-one correspondence.

7. The switching power supply according to claim 6, characterized in that, If the battery module includes a positive battery module and a negative battery module, the second switch module includes a second switch and a third switch; The first end of the second switch is connected to one of the multiple inductors, and the second end of the second switch is connected to the positive terminal of the positive battery module. The second end of the third switch is connected to another inductor among the plurality of inductors, and the second end of the third switch is connected to the negative terminal of the negative battery module.

8. The switching power supply according to claim 6, characterized in that, If the battery module includes a positive battery module, the second switch module includes a fourth switch, the first end of the fourth switch is connected to one of the inductors of the plurality of inductors, the second end of the fourth switch is connected to the positive terminal of the positive battery module, wherein the negative terminal of the positive battery module is connected to another inductor of the plurality of inductors.

9. The switching power supply according to claim 1, characterized in that, The switching power supply also includes a battery charging circuit, which is connected between the bus capacitor and the battery module.

10. A UPS, characterized in that, Includes the switching power supply, energy storage device, and inverter as described in any one of claims 1 to 9; 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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