Power supply circuit and electronic device

Abstract

The application provides a power supply circuit and electronic equipment, which can not only realize charging and discharging of an energy storage unit, but also charge the energy storage unit through an auxiliary control unit when real-time direct current voltage of the energy storage unit is lower than a first direct current voltage provided by a direct current power supply, so as to avoid damage to the power supply circuit and the energy storage unit, and further avoid fire of the power supply circuit, and improve reliability and safety of the power supply circuit. The power supply circuit can include a main control unit and an auxiliary control unit, the main control unit and the auxiliary control unit can be connected with the energy storage unit and a load unit respectively, the energy storage unit is connected with the load unit, and the load unit can be connected with the direct current power supply.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, and more specifically, to a power supply circuit and electronic equipment. Background Technology

[0002] With the rapid development of new energy technologies, energy storage units (such as energy storage batteries) have been widely used. Typically, the electrical energy stored in the energy storage unit can be transferred to the load unit via a power supply circuit, and DC power from a DC power source can also be transferred to the energy storage unit via the same circuit. In other words, the energy storage unit can be charged and discharged through the power supply circuit.

[0003] Since power supply circuits typically include power electronic devices, failure of these devices can prevent energy storage units from charging or discharging through the power supply circuit, or even damage the energy storage units themselves. Therefore, there is an urgent need for a technical solution with both high reliability and safety. Summary of the Invention

[0004] This application provides a power supply circuit and electronic device that can not only charge and discharge the energy storage unit, but also charge the energy storage unit through an auxiliary control unit when the real-time DC voltage of the energy storage unit is lower than the first DC voltage provided by the DC power supply, thus avoiding damage to the power supply circuit and the energy storage unit, and preventing the power supply circuit from catching fire, thereby improving the reliability and safety of the power supply circuit.

[0005] In a first aspect, this application provides a power supply circuit that may include a main control unit and an auxiliary control unit.

[0006] The main control unit can be connected to both the energy storage unit and the load unit, and the auxiliary control unit can also be connected to both the energy storage unit and the load unit. The energy storage unit can be connected to the load unit, and the load unit can be connected to a DC power supply.

[0007] Optionally, the DC power supply can be used to: provide a first DC voltage (which can be used as the output voltage of the DC power supply) to the load unit, and / or to provide a first DC voltage to the energy storage unit through the power supply circuit.

[0008] It is conceivable that the DC power supply can provide the first DC voltage to the load unit, or it can provide the first DC voltage to the energy storage unit through the power supply circuit (i.e., charge the energy storage unit), or it can charge the energy storage unit through the power supply circuit while providing the first DC voltage to the load unit.

[0009] The auxiliary control unit can be used to charge the energy storage unit according to the first DC voltage when the real-time DC voltage of the energy storage unit is lower than the first DC voltage (the first DC voltage is prone to impacting the power supply circuit and the energy storage unit).

[0010] It is understandable that when the real-time DC voltage of the energy storage unit is lower than the first DC voltage, in order to avoid the main control unit being damaged by the impact of the first DC voltage on the main control unit, the auxiliary control unit can charge the energy storage unit according to the first DC voltage. This can also be understood as the auxiliary control unit pre-charging the energy storage unit.

[0011] The main control unit can be used to charge the energy storage unit according to the first DC voltage when the real-time DC voltage of the energy storage unit is equal to the first DC voltage.

[0012] It should be noted that the real-time DC voltage of the energy storage unit does not necessarily have to be absolutely equal to the first DC voltage. In other words, during the charging process of the energy storage unit, as long as the voltage difference between the first DC voltage and the real-time DC voltage of the energy storage unit is within a preset threshold range, the real-time DC voltage of the energy storage unit can be considered equal to the first DC voltage. That is, the real-time DC voltage of the energy storage unit and the first DC voltage can be equal within a certain threshold range.

[0013] The power supply circuit provided in this application, when the real-time DC voltage of the energy storage unit is lower than the first DC voltage provided by the DC power supply, allows the output current of the DC power supply to flow through the auxiliary control unit, making the voltage difference across the main control unit close to 0V. This enables the main control unit to achieve zero-voltage closure, reducing the impact of the first DC voltage on the main control unit. In other words, the energy storage unit is charged through the auxiliary control unit, and the main control unit is protected from damage due to the smaller impact. Because the impact on the main control unit is reduced, it will not cause a fire in the power supply circuit, thus improving the reliability and safety of the power supply circuit.

[0014] In one possible implementation, the power supply circuit provided in this application may further include a DC-DC converter unit, which may be connected to the main control unit, the auxiliary control unit, and the energy storage unit.

[0015] Optionally, the DC-DC converter unit can be used to: charge the energy storage unit according to the main control unit and the auxiliary control unit when the real-time DC voltage of the energy storage unit is lower than the first DC voltage; and also to reduce the first DC voltage to limit the charging current of the energy storage unit.

[0016] Understandably, reducing the first DC voltage of the DC-DC converter means reducing the output voltage of the DC-DC converter. Since the output voltage and output current of the DC-DC converter are directly proportional, the output current of the DC-DC converter also decreases. Furthermore, since the charging current of the energy storage unit is equal to the output current of the DC-DC converter, the charging current of the energy storage unit also decreases, thus limiting the charging current of the energy storage unit and preventing damage from overcurrent charging.

[0017] As can be seen, the DC-DC converter can be combined with the main control unit and the auxiliary control unit to charge the energy storage unit. It should be noted that since the DC-DC converter only participates in the charging of the energy storage unit and does not participate in the discharging of the energy storage unit, it can be considered that the DC-DC converter is only turned on during the charging process of the energy storage unit and needs to be turned off during the discharging process of the energy storage unit.

[0018] In one possible implementation, the main control unit may include a first switch unit and a second switch unit, and the auxiliary control unit may include a third switch unit and a fourth switch unit.

[0019] Specifically, the first end of the first switching unit can be connected to the first end of the energy storage unit, and the second end of the first switching unit can be connected to the first node. The first ends of the second and third switching units can be connected to the first node respectively, the second end of the second switching unit can be connected to the second node, the second end of the third switching unit can be connected to the second end of the fourth switching unit, and the first end of the fourth switching unit can be connected to the second node. The second node and the first end of the DC power supply are respectively connected to the first end of the load unit, and the second end of the energy storage unit and the second end of the DC power supply are respectively connected to the second end of the load unit.

[0020] Furthermore, the first end of the DC-DC converter can be connected to the node between the third and fourth switching units, the second end of the DC-DC converter can be connected to the first node or the node between the first switching unit and the energy storage unit (that is, the second end of the DC-DC converter can be connected to the first node, and the second end of the DC-DC converter can also be connected to the node between the first switching unit and the energy storage unit), and the third end of the DC-DC converter can be connected to the second end of the energy storage unit and the second end of the load unit.

[0021] In another possible implementation, the main control unit may include a first switch unit and a second switch unit, and the auxiliary control unit may include a third switch unit and a fourth switch unit.

[0022] The first end of the first switching unit can be connected to the second end of the energy storage unit. The second end of the first switching unit and the second end of the DC power supply can be connected to the second end of the load unit respectively. The first end of the energy storage unit, the first end of the second switching unit, and the first end of the third switching unit can be connected to the first node respectively. The second end of the second switching unit can be connected to the second node. The second end of the third switching unit can be connected to the second end of the fourth switching unit. The first end of the fourth switching unit can be connected to the second node. The second node and the first end of the DC power supply can be connected to the first end of the load unit respectively.

[0023] In one example, the first end of the DC-DC converter can be connected to the node between the third and fourth switching units, the second end of the DC-DC converter can be connected to the first node, and the third end of the DC-DC converter can be connected to the second end of the first switching unit and the second end of the load unit.

[0024] In another example, the first end of the DC-DC converter can be connected to the node between the third and fourth switching units, the second end of the DC-DC converter can be connected to the first node, and the third end of the DC-DC converter can be connected to the first end of the first switching unit and the second end of the energy storage unit.

[0025] In one possible implementation, the power supply circuit for charging the energy storage unit may include: when the first switching unit is turned on and the real-time DC voltage of the energy storage unit is lower than the first DC voltage, the power supply circuit controls the fourth switch to close and the third switching unit to turn on, and provides the first DC voltage to the energy storage unit through the fourth switching unit, the third switching unit and the first switching unit, thereby achieving pre-charging of the energy storage unit through the DC power supply.

[0026] Optionally, in addition to charging the energy storage unit when the real-time DC voltage of the energy storage unit is lower than the first DC voltage, the auxiliary control unit can also be used to: supply power to the load unit according to the real-time DC voltage of the energy storage unit when the first DC voltage is lower than the rated voltage of the load unit (the first DC voltage provided by the DC power supply cannot meet the normal operation of the load unit); or, charge the energy storage unit according to the first DC voltage when the real-time DC voltage of the energy storage unit is equal to the first DC voltage.

[0027] The main control unit can also be used to supply power to the load unit based on the real-time DC voltage of the energy storage unit when the first DC voltage is lower than the rated voltage of the load unit.

[0028] In one example, the power supply circuit for charging the energy storage unit may include: when the first switching unit is turned on and the real-time DC voltage of the energy storage unit is equal to the first DC voltage, the power supply circuit may control the fourth switching unit to be turned off, the third switching unit to be turned off and the second switching unit to be turned on, and provide the first DC voltage to the energy storage unit through the second switching unit and the first switching unit to realize the charging of the energy storage unit.

[0029] Similarly, the power supply circuit for supplying power to the load unit may include: when the first DC voltage is lower than the rated voltage of the load unit, the power supply circuit may control the third switch unit to turn off, the fourth switch unit to open, the second switch unit to close and the first switch unit to turn on, and supply the real-time DC voltage of the energy storage unit to the load unit through the first switch unit and the second switch unit, thereby achieving power supply to the load unit through the discharge of the energy storage unit.

[0030] Furthermore, the power supply circuit for charging the energy storage unit may include: when the real-time DC voltage of the energy storage unit is lower than the first DC voltage, the power supply circuit controls the DC-DC converter unit to open, the fourth switch unit to close, and the first switch unit to conduct, and provides the first DC voltage to the energy storage unit through the fourth switch unit, the DC-DC converter unit, and the first switch unit to realize the charging of the energy storage unit.

[0031] In another example, the power supply circuit for charging the energy storage unit may include: when the first switching unit is turned on and the real-time DC voltage of the energy storage unit is equal to the first DC voltage, the power supply circuit may control the second switching unit to be turned off, the fourth switching unit to be turned on and the third switching unit to be turned on, and provide the first DC voltage to the energy storage unit through the fourth switching unit, the third switching unit and the first switching unit to realize the charging of the energy storage unit.

[0032] Similarly, the power supply circuit for supplying power to the load unit may include: when the first DC voltage is lower than the rated voltage of the load unit, the power supply circuit controls the second switch unit to turn off, the fourth switch unit to close, the third switch unit to turn on, and the first switch unit to turn on, and supplies the real-time DC voltage of the energy storage unit to the load unit through the first switch unit, the third switch unit, and the fourth switch unit, and realizes the power supply of the load unit through the discharge of the energy storage unit.

[0033] Furthermore, the power supply circuit for charging the energy storage unit may include: when the real-time DC voltage of the energy storage unit is lower than the first DC voltage, the power supply circuit may control the DC-DC converter unit to open, the fourth switch unit to close, and the first switch unit to conduct, and transmit the first DC voltage to the energy storage unit through the fourth switch unit, the DC-DC converter unit, and the first switch unit to realize the charging of the energy storage unit.

[0034] In another example, the power supply circuit for charging the energy storage unit may include: when the first switching unit is turned on and the real-time DC voltage of the energy storage unit is equal to the first DC voltage, the power supply circuit controls the fourth switching unit to close, the third switching unit to turn on and the second switching unit to close, and provides the first DC voltage to the energy storage unit through the second switching unit and the first switching unit, and also provides the first DC voltage to the energy storage unit through the fourth switching unit, the third switching unit and the first switching unit, thereby realizing the charging of the energy storage unit.

[0035] Similarly, the power supply circuit for supplying power to the load unit may include: when the first DC voltage is lower than the rated voltage of the load unit, the power supply circuit controls the fourth switch unit to close, the third switch unit to turn on, the second switch unit to close and the first switch unit to turn on, and transmits the real-time DC voltage of the energy storage unit to the load unit through the first switch unit and the second switch unit, and also provides the real-time DC voltage of the energy storage unit to the load unit through the first switch unit, the third switch unit and the fourth switch unit, and supplies power to the load unit by discharging the energy storage unit.

[0036] Furthermore, the power supply circuit for charging the energy storage unit may include: when the real-time DC voltage of the energy storage unit is lower than the first DC voltage provided by the DC power supply, the power supply circuit controls the DC-DC converter unit to open, the fourth switch unit to close, and the first switch unit to conduct, and provides the first DC voltage to the energy storage unit through the fourth switch unit, the DC-DC converter unit, and the first switch unit to realize the charging of the energy storage unit.

[0037] In one possible implementation, the first switching unit and the third switching unit may each include a power switch or multiple power switches connected in parallel.

[0038] In other words, the first switching unit may include one power switch or multiple power switches, and the multiple power switches may be connected in parallel.

[0039] Similarly, the third switching unit may include one power switch or multiple power switches, which may be connected in parallel.

[0040] Optionally, the power switch can be an insulated-gate field-effect transistor (MOSFET) or an insulated-gate bipolar transistor (IGBT). The MOSFET can be a silicon carbide (SiC) MOSFET or a gallium nitride (GaN) MOSFET, etc. Of course, the power switch can also be other power transistors, which is not limited in this application.

[0041] As can be seen, the operating modes of the power supply circuit provided in this application can include pre-charging mode, charging mode, discharging mode, and protection mode. By controlling the opening (i.e., turning off) and closing (i.e., turning on) sequence of the four switching units, the power supply circuit can operate in different modes, thereby realizing the charging and discharging of the energy storage unit and the power supply of the load unit.

[0042] In one possible implementation, the second and fourth switching units may each include one or more mechanical switches.

[0043] In other words, the second switching unit may include one mechanical switch or multiple mechanical switches. Multiple mechanical switches may be connected in series, in parallel, or in a combination of series and parallel connections.

[0044] Similarly, the fourth switching unit may include one mechanical switch or multiple mechanical switches. Multiple mechanical switches may be connected in series, in parallel, or in a combination of series and parallel connections.

[0045] Optionally, the mechanical switch can be any one of a relay, contactor, and air switch (such as an air switch capable of intelligent closing or intelligent opening, which can be called an intelligent air switch). Of course, the mechanical switch can also be other types, which are not limited in this application.

[0046] It is conceivable that, since the third switching unit uses a power switch (such as a MOSFET) and the fourth switching unit uses a mechanical switch (such as a relay), and the third and fourth switching units are connected, the charging current of the energy storage unit can be limited through the third switching unit and the detection unit in the power supply circuit. In other words, the auxiliary control unit, including the third switching unit, can reduce the impact on the energy storage unit and prevent damage. Furthermore, the third switching unit can prevent the first DC voltage from impacting the fourth switching unit, thus protecting the fourth switching unit.

[0047] It can be seen that the third switching unit serves to limit the charging current of the energy storage unit and protect the fourth switching unit. Therefore, when the real-time DC voltage of the energy storage unit is lower than or equal to the first DC voltage, the current flowing from the DC power supply through the auxiliary control unit will not damage the fourth switching unit. Consequently, the auxiliary control unit can protect the second switching unit in the main control unit.

[0048] The power supply circuit provided in this application adopts a hybrid topology of power switches and mechanical switches, which can achieve the discharge of the energy storage unit through only the main control unit or only the auxiliary control unit. It can be seen that during the discharge process of the energy storage unit, it is not necessary for all four switching units to be closed (or turned on), which can reduce the overall loss and total heat generation of the power supply circuit and improve its reliability.

[0049] Secondly, this application provides an electronic device that may include an energy storage unit and a power supply circuit provided by the first aspect and its possible implementations. The power supply circuit may be connected to the energy storage unit and a load unit respectively, and the load unit may be connected to a DC power supply.

[0050] The power supply circuit can be used to charge the energy storage unit according to the first DC voltage when the real-time DC voltage of the energy storage unit is lower than or equal to the first DC voltage.

[0051] In one possible implementation, the electronic device could be a battery used to power base stations, data centers, or backup power equipment.

[0052] It should be understood that the second aspect of this application is consistent with the technical solution of the first aspect of this application, and the beneficial effects achieved by each aspect and the corresponding feasible implementation are similar, so they will not be repeated here. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0055] Figure 2 This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0056] Figure 3 This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0057] Figure 4 This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0058] Figure 5 This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0059] Figure 6 This is a schematic diagram showing the current flow and path in the pre-charging mode of the power supply circuit in the embodiments of this application;

[0060] Figure 7 This is a schematic diagram showing the current flow and path in the charging mode of the power supply circuit in the embodiments of this application;

[0061] Figure 8 This is a schematic diagram showing the current flow and path in the charging mode of the power supply circuit in the embodiments of this application;

[0062] Figure 9 This is a schematic diagram showing the current flow and path in the discharge mode of the power supply circuit in the embodiments of this application;

[0063] Figure 10This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0064] Figure 11 This is a schematic diagram showing the current flow and path in the pre-charging mode of the power supply circuit in the embodiments of this application;

[0065] Figure 12 This is a schematic diagram showing the current flow and path in the charging mode of the power supply circuit in the embodiments of this application;

[0066] Figure 13 This is a schematic diagram showing the current flow and path in the charging mode of the power supply circuit in the embodiments of this application;

[0067] Figure 14 This is a schematic diagram showing the current flow and path in the discharge mode of the power supply circuit in the embodiments of this application;

[0068] Figure 15 This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0069] Figure 16 This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0070] Figure 17 This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0071] Figure 18 This is a schematic diagram showing the current flow and path in the pre-charging mode of the power supply circuit in the embodiments of this application;

[0072] Figure 19 This is a schematic diagram showing the current flow and path in the charging mode of the power supply circuit in the embodiments of this application;

[0073] Figure 20 This is a schematic diagram showing the current flow and path in the charging mode of the power supply circuit in the embodiments of this application;

[0074] Figure 21 This is a schematic diagram showing the current flow and path in the discharge mode of the power supply circuit in the embodiments of this application;

[0075] Figure 22 This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0076] Figure 23 This is a schematic structural diagram of the power supply circuit in an embodiment of this application;

[0077] Figure 24 This is a schematic diagram showing the current flow and path in the pre-charging mode of the power supply circuit in the embodiments of this application;

[0078] Figure 25This is a schematic diagram showing the current flow and path in the charging mode of the power supply circuit in the embodiments of this application;

[0079] Figure 26 This is a schematic diagram showing the current flow and path in the charging mode of the power supply circuit in the embodiments of this application;

[0080] Figure 27 This is a schematic diagram showing the current flow and path in the discharge mode of the power supply circuit in the embodiments of this application;

[0081] Figure 28 This is a schematic structural diagram of the electronic device in the embodiments of this application. Detailed Implementation

[0082] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0083] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0084] The terms "first," "second," etc., used in the specification, embodiments, claims, and drawings of this application are for distinguishing purposes only and should not be construed as indicating or implying relative importance or order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as including a series of steps or units. A method, system, product, or apparatus is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or apparatuses.

[0085] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0086] With the rapid development of new energy technologies, energy storage units (such as energy storage batteries) have been widely used. Typically, the electrical energy stored in the energy storage unit can be transferred to the load unit via a power supply circuit, and DC power from a DC power source can also be transferred to the energy storage unit via the same circuit. In other words, the energy storage unit can be charged and discharged through the power supply circuit.

[0087] Since power supply circuits typically include power electronic devices, failure of these devices can prevent energy storage units from charging or discharging through the power supply circuit, or even damage the energy storage units themselves. Therefore, there is an urgent need for a technical solution with both high reliability and safety.

[0088] To overcome the above problems, embodiments of this application provide a power supply circuit for charging and discharging an energy storage unit. For example... Figure 1 As shown, the power supply circuit 1 may include a main control unit 10 and an auxiliary control unit 20.

[0089] The main control unit 10 can be connected to the energy storage unit (ESU) and the load unit (LU), and the auxiliary control unit 20 can also be connected to the energy storage unit (ESU) and the load unit (LU). The energy storage unit (ESU) can be connected to the load unit (LU), and the load unit (LU) can be connected to a direct current power supply (DCPS).

[0090] Optionally, the DC power supply DCPS can be used to: provide a first DC voltage (which can be used as the output voltage of the DC power supply) to the load unit LU, and / or to provide a first DC voltage to the energy storage unit ESU through the power supply circuit A.

[0091] It is conceivable that the DC power supply DCPS can provide the first DC voltage to the load unit LU, or it can provide the first DC voltage to the energy storage unit ESU through the power supply circuit 1 (i.e., charge the energy storage unit ESU), or it can charge the energy storage unit ESU through the power supply circuit 1 while providing the first DC voltage to the load unit LU.

[0092] The auxiliary control unit 20 can be used to charge the energy storage unit ESU according to the first DC voltage when the real-time DC voltage of the energy storage unit ESU is lower than the first DC voltage (the first DC voltage is likely to cause an impact on the power supply circuit 1 and the energy storage unit ESU).

[0093] It is understandable that when the real-time DC voltage of the energy storage unit ESU is lower than the first DC voltage, in order to avoid the main control unit 10 being damaged by the impact of the first DC voltage on the main control unit 10, the auxiliary control unit 20 can charge the energy storage unit ESU according to the first DC voltage. It can also be understood that the auxiliary control unit 20 pre-charges the energy storage unit ESU.

[0094] The main control unit 10 can be used to charge the energy storage unit ESU according to the first DC voltage when the real-time DC voltage of the energy storage unit ESU is equal to the first DC voltage.

[0095] It should be noted that the real-time DC voltage of the energy storage unit (ESU) does not necessarily have to be absolutely equal to the first DC voltage. In other words, during the charging process of the ESU, as long as the voltage difference between the first DC voltage and the real-time DC voltage of the ESU is within a preset threshold range, the real-time DC voltage of the ESU can be considered equal to the first DC voltage. That is, the real-time DC voltage of the ESU and the first DC voltage can be equal within a certain threshold range.

[0096] In the case of a short circuit in the load unit or a real-time DC voltage of the energy storage unit lower than the first DC voltage provided by the DC power supply, the output current of the DC power supply flows through the auxiliary control unit, making the voltage difference across the main control unit close to 0V. This allows the main control unit to achieve zero-voltage closure, reducing the impact on the main control unit. In other words, the energy storage unit is charged through the auxiliary control unit, and the main control unit is protected from damage due to the smaller impact. Because the impact on the main control unit is reduced, it will not cause a fire in the power supply circuit, thus improving the reliability and safety of the power supply circuit.

[0097] Optionally, in addition to charging the energy storage unit ESU when the real-time DC voltage of the energy storage unit ESU is lower than the first DC voltage, the auxiliary control unit 20 can also be used to: supply power to the load unit LU according to the real-time DC voltage of the energy storage unit ESU when the first DC voltage is lower than the rated voltage of the load unit LU (the first DC voltage provided by the DC power supply DCPS cannot meet the normal operation of the load unit LU); or, charge the energy storage unit ESU according to the first DC voltage when the real-time DC voltage of the energy storage unit ESU is equal to the first DC voltage.

[0098] The main control unit 10 can also be used to supply power to the load unit LU according to the real-time DC voltage of the energy storage unit ESU when the first DC voltage is lower than the rated voltage of the load unit LU.

[0099] In one possible implementation, the power supply circuit 1 provided in this application may further include a direct current transforming unit (DCTU), which may be connected to the main control unit 10, the auxiliary control unit 20 and the energy storage unit ESU.

[0100] Optionally, the DC-DC converter unit (DCTU) can be used to charge the energy storage unit (ESU) according to the main control unit 10 and the auxiliary control unit 20, and limit the charging current of the energy storage unit (ESU) when the real-time DC voltage of the energy storage unit (ESU) is lower than the first DC voltage.

[0101] It can be seen that the DC-DC converter unit (DCTU) can be combined with the main control unit 10 and the auxiliary control unit 20 to realize the charging of the energy storage unit (ESU). It should be noted that since the DC-DC converter unit only needs to participate in the charging of the energy storage unit (ESU) and does not participate in the discharging of the energy storage unit (ESU), it can be considered that the DC-DC converter unit (DCTU) will only be turned on during the charging process of the energy storage unit (ESU) and needs to be turned off during the discharging process of the energy storage unit (ESU).

[0102] In one example, such as Figure 2 As shown, the main control unit 10 includes a first switch unit 101 and a second switch unit 102, and the auxiliary control unit 20 includes a third switch unit 103 and a fourth switch unit 104.

[0103] Among them, the first terminal of the first switching unit 101 (such as Figure 2 The left end of the first switching unit 101 can be connected to the first end of the energy storage unit ESU (such as...). Figure 2 The upper end of the energy storage unit ESU can be connected to the positive terminal of the energy storage unit ESU, and the second terminal of the first switching unit 101 (such as...) Figure 2 The right end of the first switching unit 101 can be connected to node A (i.e., the first node), and the first end of the second switching unit 102 (such as...) Figure 2 The left end of the second switching unit 102 and the first end of the third switching unit 103 (as shown in the image) Figure 2 The left end of the third switch unit 103 can be connected to node A, and the second end of the second switch unit 102 (such as...) Figure 2 The right end of the second switching unit 102 can be connected to node B (i.e., the second node), and the second end of the third switching unit 103 (such as...) Figure 2 The right end of the third switch unit 103 can be connected to the second end of the fourth switch unit 104 (e.g., Figure 2 The lower end of the fourth switch unit 104 is connected, and the first end of the fourth switch unit 104 (such as...) Figure 2The upper end of the fourth switching unit 104 can be connected to node B. Node B and the first terminal of the DC power supply DCPS can be the positive terminal of the DC power supply DCPS, such as... Figure 2 The upper end of the DC power supply (DCPS) can be connected to the first end of the load unit LU (which can be the positive terminal of the load unit LU, such as...) through node E. Figure 2 The upper end of the medium load unit LU) is connected to the second end of the energy storage unit ESU (such as...). Figure 2 The lower end of the energy storage unit ESU (which can be the negative terminal of the energy storage unit ESU) and the second terminal of the DC power supply DCPS (which can be the negative terminal of the DC power supply DCPS, such as...) Figure 2 The lower end of the DC power supply (DCPS) can be connected to the second end of the load unit LU (which can be the negative terminal of the load unit LU, such as...) through node F. Figure 2 (Connect to the lower end of the load unit LU).

[0104] In one example, an embodiment of this application Figure 3 The power supply circuit 1 shown may include a DC-DC converter unit (DCTU). The first terminal of the DC-DC converter unit (which may be the input terminal of the DC-DC converter unit, such as...) Figure 3 The right end of the DC-DC converter unit (DCTU) can be connected to node D (i.e., Figure 3 The node between the third switching unit 103 and the fourth switching unit 104, and the second terminal of the DC-DC converter (which can be the output terminal of the DC-DC converter, such as...) Figure 3 The left end of the DC-DC converter unit (DCTU) can be connected to node A (it can be considered that the output of the DCTU is connected to node C, and node C is then connected to node A). The third end of the DCTU (can be the reference ground of the DCTU, such as...) Figure 3 The lower end of the DC-DC converter unit (DCTU) can be connected to the second end of the energy storage unit (ESU). Simultaneously, the third end of the DC-DC converter unit (DCTU) can be connected to the second end of the load unit (LU) via node F.

[0105] In other words, the reference ground terminal of the DC-DC converter (DCTU), the negative terminal of the energy storage unit (ESU), and the negative terminal of the load unit (LU) can be connected to node F, and node F is then connected to the reference ground. Alternatively, the DC-DC converter (DCTU), the energy storage unit (ESU), and the load unit (LU) can share a common ground.

[0106] In another example, such as Figure 4 As shown, the first terminal of the DC-DC converter (DCTU) can be the input terminal of the DC-DC converter, such as... Figure 4 The right end of the DC-DC converter unit (DCTU) is connected to node D (i.e., Figure 3The node between the third switching unit 103 and the fourth switching unit 104, and the second terminal of the DC-DC converter (which can be the output terminal of the DC-DC converter, such as...) Figure 4 The left end of the DC-DC converter unit (DCTU) can be connected to node G (i.e., Figure 4 The node between the first switching unit 101 and the energy storage unit ESU), and the third terminal of the DC-DC converter unit (which can be the reference ground terminal of the DC-DC converter unit, such as...). Figure 4 The lower end of the DC-DC converter unit (DCTU) can be connected to the second end of the energy storage unit (ESU) (e.g., Figure 4 (The negative terminal of the energy storage unit ESU). At the same time, the third terminal of the DC-DC converter unit DCTU can be connected to the second terminal of the load unit LU through node F.

[0107] and Figure 3 same, Figure 4 The reference ground terminal of the DC-DC converter (DCTU), the negative terminal of the energy storage unit (ESU), and the negative terminal of the load unit (LU) can also be connected to node F, and node F is then connected to the reference ground. Alternatively, it can be considered that... Figure 4 The DC-DC converter (DCTU), energy storage unit (ESU), and load unit (LU) can share a common ground.

[0108] In one possible implementation, Figure 3 In the power supply circuit 1 shown, the first switching unit 101 may include a power switch or a plurality of power switches connected in parallel.

[0109] Similarly, the third switching unit 103 may also include a power switch or multiple power switches connected in parallel.

[0110] Furthermore, the power switch is an insulated-gate field-effect transistor (MOSFET) or an insulated-gate bipolar transistor (IGBT). The MOSFET can be a silicon carbide (SiC) MOSFET or a gallium nitride (GaN) MOSFET, etc. Of course, the power switch can also be other power transistors, and this application embodiment is not limited thereto.

[0111] In another possible implementation Figure 3 In the power supply circuit 1 shown, the second switching unit 102 may include one mechanical switch or multiple mechanical switches. In the scenario where the second switching unit 102 includes multiple mechanical switches, the multiple mechanical switches may be connected in series, in parallel, or in a combination of series and parallel.

[0112] Similarly, the fourth switching unit 104 may include one mechanical switch or multiple mechanical switches. In the scenario where the fourth switching unit 104 includes multiple mechanical switches, the multiple mechanical switches may be connected in series, in parallel, or in a combination of series and parallel.

[0113] Furthermore, the mechanical switch can be any one of a relay, contactor, and circuit breaker (such as a circuit breaker capable of intelligent closing or intelligent opening, which can be called an intelligent circuit breaker). Of course, the mechanical switch can also be other types, and this application embodiment does not limit it.

[0114] This application embodiment uses the energy storage unit ESU as the lithium battery B (battery) 1, and exemplifies that the first switching unit 101 and the third switching unit 103 each include a MOSFET (simply referred to as a MOS transistor), and the second switching unit 102 and the fourth switching unit 104 each include a relay, as examples are provided. Figure 5 As shown.

[0115] refer to Figure 5 The drain of the first switching unit 101 (i.e., the first terminal of the first switching unit 101) can be connected to the positive terminal (i.e., the first terminal of the lithium battery B1), and the source of the first switching unit 101 (i.e., the second terminal of the first switching unit 101) can be connected to node A. The first terminal of the second switching unit 102 (i.e., the source of the first switching unit 101) can be connected to node A. Figure 5 The left end of the second switching unit 102 and the source of the third switching unit 103 (i.e., the first end of the third switching unit 103) can be connected to node A respectively (the source of the third switching unit 103 is connected to node A through node C), and the second end of the second switching unit 102 (i.e., the left end of the second switching unit 102) and the source of the third switching unit 103 (i.e., the first end of the third switching unit 103) can be connected to node A respectively. Figure 5 The right end of the second switching unit 102 can be connected to node B, and the drain of the third switching unit 103 (i.e., the second end of the third switching unit 103) can be connected to the second end of the fourth switching unit 104 (i.e., the right end of the third switching unit 103). Figure 5 The lower end of the fourth switch unit 104 is connected, and the first end of the fourth switch unit 104 (i.e., Figure 5 The upper end of the fourth switching unit 104 can be connected to node B. Node B can be connected to the positive terminal of the load unit LU (i.e., the first end of the load unit LU) through node E. The negative terminal of the load unit LU can be connected to the negative terminal of the lithium battery B1 (i.e., the second end of the lithium battery B1).

[0116] The first terminal of the DC-DC converter unit (DCTU) is connected to node D, and the second terminal of the DC-DC converter unit can be connected to node C. The reference ground terminal of the DC-DC converter unit can be connected to the negative terminal of the lithium battery B1. Simultaneously, the reference ground terminal of the DC-DC converter unit can be connected to the negative terminal of the load unit LU through node F.

[0117] Figure 5 The reference ground terminal of the DC-DC converter unit (DCTU), the negative terminal of the lithium battery B1, and the negative terminal of the load unit LU can also be connected to node F, and node F is then connected to the reference ground. Alternatively, it can be considered that... Figure 5 The DC-DC converter unit (DCTU), lithium battery B1, and load unit LU can share a common ground.

[0118] Optionally, in practical application scenarios, Figure 5 The power supply circuit 1 shown can have a pre-charge mode, a charging mode, a discharging mode, and a protection mode. That is to say, Figure 5 The power supply circuit 1 shown can realize the pre-charging, charging, discharging, and protection of the energy storage unit. The pre-charging, charging, discharging, and protection of the energy storage unit through the power supply circuit 1 are described below.

[0119] (1) Pre-charging

[0120] In the pre-charging mode, the first switching unit 101 is in the on state and the second switching unit 102 is in the off state. Therefore, when the first switching unit 101 is on and the real-time DC voltage of the energy storage unit ESU is lower than the first DC voltage, the power supply circuit 1 can control the DC-DC converter unit DCTU to turn off, the fourth switching unit 104 to close and the third switching unit 103 to turn on, and supply the first DC voltage to the energy storage unit ESU through the fourth switching unit 104, the third switching unit 103 and the first switching unit 101 to realize the pre-charging of the energy storage unit ESU.

[0121] The direction and path of current flow can be as follows Figure 6 As shown, the current output by the DC power supply DCPS can pass through the fourth switch unit 104, the third switch unit 103, the first switch unit 101 and the lithium battery B1 in sequence, and finally return to the DC power supply DCPS to form a complete loop, thereby realizing the pre-charging of the lithium battery B1.

[0122] (2) Charging

[0123] Based on the relationship between the terminal voltage of lithium battery B1 (i.e., real-time DC voltage) and the DC voltage output by DC power supply DCPS (i.e., the first DC voltage), the charging of energy storage unit ESU by power supply circuit 1 can be divided into the following two cases:

[0124] Scenario 1: When the terminal voltage of lithium battery B1 is equal to the DC voltage output by DC power supply DCPS, power supply circuit 1 can charge lithium battery B1 through the following three methods:

[0125] Method 1: When the first switching unit 101 is in the conducting state, and the real-time DC voltage of the energy storage unit ESU is equal to the first DC voltage, the power supply circuit 1 can control the DC-DC converter unit DCTU to turn off, the fourth switching unit 104 to open, the third switching unit 103 to turn off, and the second switching unit 102 to close, and supply the first DC voltage to the energy storage unit ESU through the second switching unit 102 and the first switching unit 101.

[0126] The direction and path of current flow can be Figure 7 In the circuit L1, the current output by the DC power supply DCPS can pass through the second switching unit 102, the first switching unit 101 and the lithium battery B1 in sequence, and finally return to the DC power supply DCPS to form a complete circuit and realize the charging of the lithium battery B1.

[0127] Method 2: When the first switching unit 101 is in the on state, the power supply circuit 1 can control the DC-DC converter unit DCTU to be turned off, the second switching unit to be turned off, the fourth switching unit 104 to be turned on and the third switching unit 103 to be turned on, and the first DC voltage is supplied to the energy storage unit ESU through the fourth switching unit 104, the third switching unit 103 and the first switching unit 101.

[0128] The direction and path of current flow can be Figure 7 In L2, the current output by the DC power supply DCPS can pass through the fourth switch unit 104, the third switch unit 103, the first switch unit 101 and the lithium battery B1 in sequence, and finally return to the DC power supply DCPS to form a complete circuit and realize the charging of the lithium battery B1.

[0129] Method 3: With the first switching unit 101 in the ON state, the power supply circuit 1 can control the DC-DC converter (DCTU) to OFF, the fourth switching unit 104 to OFF, the third switching unit 103 to OFF, and the second switching unit 102 to OFF. The power supply circuit 1 can supply the first DC voltage to the energy storage unit (ESU) not only through the second switching unit 102 and the first switching unit 101, but also through the fourth switching unit 104, the third switching unit 103, and the first switching unit 101.

[0130] The direction and path of current flow can be Figure 7The L1 and L2 paths represent two possible current paths. Path L1 shows the current output from the DC power supply (DCPS) passing sequentially through the second switching unit 102, the first switching unit 101, and the lithium battery B1, before returning to the DC power supply (DCPS). Path L2 shows the current output from the DC power supply (DCPS) passing sequentially through the fourth switching unit 104, the third switching unit 103, the first switching unit 101, and the lithium battery B1, before returning to the DC power supply (DCPS). Both L1 and L2 can form a complete circuit, thus enabling the charging of the lithium battery B1.

[0131] Scenario 2: When the terminal voltage of lithium battery B1 is less than the DC voltage output by DC power supply DCPS (i.e., the voltage difference between the DC voltage output by DC power supply DCPS and the terminal voltage of lithium battery B1 is large), power supply circuit 1 can control DC converter unit DCTU to open, fourth switch unit 104 to close and first switch unit 101 to conduct, and provide the first DC voltage to energy storage unit ESU through fourth switch unit 104, DC converter unit DCTU and first switch unit 101.

[0132] Understandably, the DC-DC converter (DCTU) lowers the first DC voltage, which means it lowers the output voltage of the DCTU. Since the output voltage and output current of the DCTU are directly proportional, the output current of the DCTU also decreases. Furthermore, since the charging current of lithium battery B1 is equal to the output current of the DCTU, the charging current of lithium battery B1 also decreases. Therefore, the DCTU can achieve current-limited charging of lithium battery B1, preventing damage to it.

[0133] The direction and path of current flow can be as follows Figure 8 As shown, the current output from the DC power supply DCPS can sequentially pass through the fourth switching unit 104, the DC-DC converter unit DCTU, the first switching unit 101, and the lithium battery B1, finally returning to the DC power supply DCPS. This can also form a complete circuit to charge the lithium battery B1.

[0134] (3) Discharge

[0135] If the rated voltage of the load unit LU is greater than the DC voltage output by the DC power supply DCPS, the load unit LU can be discharged through the lithium battery B1 to ensure normal operation.

[0136] In one example, power supply circuit 1 can control the DC-DC converter unit (DCTU) to shut down, the fourth switch unit 104 to open, the third switch unit 103 to turn off, and control the second switch unit 102 to close and the first switch unit 101 to turn on. Power supply circuit 1 provides the real-time DC voltage of the energy storage unit (ESU) to the load unit (LU) through the first switch unit 101 and the second switch unit 102.

[0137] The direction and path of current flow can be as follows Figure 9 In the circuit L1, the discharge current of lithium battery B1 can pass through the first switching unit 101, the second switching unit 102 and the load unit LU in sequence, and finally return to lithium battery B1 to form a complete circuit and realize the discharge of lithium battery B1.

[0138] In another example, power supply circuit 1 can control the DC-DC converter unit (DCTU) to turn off, the second switch unit 102 to open, the fourth switch unit 104 to close, the third switch unit 103 to turn on, and the first switch unit 101 to turn on. The real-time DC voltage of the energy storage unit (ESU) is provided to the load unit (LU) through the first switch unit 101, the third switch unit 103, and the fourth switch unit 104.

[0139] The direction and path of current flow can be as follows Figure 9 In L2, the discharge current of lithium battery B1 can pass through the first switch unit 101, the third switch unit 103, the fourth switch unit 104 and the load unit LU in sequence, and finally return to lithium battery B1 to form a complete circuit and realize the discharge of lithium battery B1.

[0140] In another example, the power supply circuit 1 can control the DC-DC converter unit (DCTU) to turn off, the fourth switch unit 104 to close, the third switch unit 103 to turn on, the second switch unit 102 to close, and the first switch unit 101 to turn on. The real-time DC voltage of the energy storage unit (ESU) is transmitted to the load unit (LU) through the first switch unit 101 and the second switch unit 102. The real-time DC voltage of the energy storage unit (ESU) is also provided to the load unit (LU) through the first switch unit 101, the third switch unit 103, and the fourth switch unit 104.

[0141] The direction and path of current flow can be as follows Figure 9 In the diagram, paths L1 and L2 (i.e., two paths) allow the discharge current of lithium battery B1 to not only pass through the first switching unit 101, the second switching unit 102, and the load unit LU in sequence, forming a complete loop, but also pass through the first switching unit 101, the third switching unit 103, the fourth switching unit 104, and the load unit LU in sequence, finally returning to lithium battery B1. It can be seen that both paths can achieve the discharge of lithium battery B1.

[0142] It should be noted that when the voltage of the load unit LU is less than the DC voltage output by the DC power supply DCPS, the load unit LU can be powered by the DC power supply DCPS. The lithium battery B1 does not need to be discharged, and the second switching unit 102 can be disconnected to reduce the energy consumption of the power supply circuit 1.

[0143] The power supply circuit provided in this application adopts a hybrid topology of MOSFETs and relays, which can achieve the discharge of the energy storage unit ESU through only the first and second switching units, or only the third and fourth switching units. It can be seen that during the discharge process of the energy storage unit ESU, it is not necessary for all four switching units to be closed (or turned on), which can reduce the overall loss and heat generation of the power supply circuit and improve its reliability.

[0144] (4) Protection

[0145] In one possible implementation, when the discharge current of the lithium battery B1 exceeds a preset current threshold, the first switching unit 101 can be directly shut down, thereby protecting the load unit LU and the power supply circuit 1.

[0146] In another possible implementation, when the charging current of lithium battery B1 exceeds a preset current threshold (i.e., lithium battery B1 is overcharged), since the first switching unit 101 is in the on state and the second switching unit 102 is in the closed state, the power supply circuit 1 can control the fourth switching unit 104 to close, the third switching unit 103 to turn on, the second switching unit 102 to open, and the third switching unit 103 to turn off, thereby achieving protection for the power supply circuit 1 and lithium battery B1.

[0147] In one possible implementation, Figure 4 In the power supply circuit 1 shown, the second switching unit 102 may include one mechanical switch or multiple mechanical switches. In the scenario where the second switching unit 102 includes multiple mechanical switches, the multiple mechanical switches may be connected in series, in parallel, or in a combination of series and parallel.

[0148] Similarly, the fourth switching unit 104 may include one mechanical switch or multiple mechanical switches. In the scenario where the fourth switching unit 104 includes multiple mechanical switches, the multiple mechanical switches may be connected in series, in parallel, or in a combination of series and parallel.

[0149] Furthermore, the mechanical switch can be any one of a relay, contactor, and circuit breaker. Of course, the mechanical switch can also be other types, which are not limited in the embodiments of this application.

[0150] Still using the energy storage unit ESU as the lithium battery B1, and taking the first switching unit 101 and the third switching unit 103 each including a MOSFET, and the second switching unit 102 and the fourth switching unit 104 each including a relay as examples, the explanation will proceed as follows: Figure 10 As shown.

[0151] refer to Figure 10 The drain of the first switching unit 101 can be connected to node C, and the source of the first switching unit 101 can be connected to node A. The first terminal of the second switching unit 102 and the source of the third switching unit 103 can be connected to node A respectively. The second terminal of the second switching unit 102 can be connected to node B. The drain of the third switching unit 103 can be connected to the second terminal of the fourth switching unit 104. The first terminal of the fourth switching unit 104 can be connected to node B. Node B can be connected to the positive terminal of the load unit LU through node E. The negative terminal of the load unit LU can be connected to the negative terminal of the lithium battery B1. The positive terminal of the lithium battery B1 is connected to node C.

[0152] The first terminal of the DC-DC converter unit (DCTU) is connected to node D, and the second terminal of the DC-DC converter unit can be connected to node C. The reference ground terminal of the DC-DC converter unit can be connected to the negative terminal of the lithium battery B1. Simultaneously, the reference ground terminal of the DC-DC converter unit can be connected to the negative terminal of the load unit LU through node F.

[0153] Figure 10 The reference ground terminal of the DC-DC converter unit (DCTU), the negative terminal of the lithium battery B1, and the negative terminal of the load unit LU can also be connected to node F, and node F is then connected to the reference ground. Alternatively, it can be considered that... Figure 10 The DC-DC converter unit (DCTU), lithium battery B1, and load unit LU can share a common ground.

[0154] Optionally, the positive terminal of the DC power supply DCPS can be connected to the positive terminal of the load unit LU through node E, and the negative terminal of the DC power supply DCPS can be connected to the negative terminal of the load unit LU through node F.

[0155] Optionally, in practical application scenarios, Figure 10 The power supply circuit 1 shown can have a pre-charge mode, a charging mode, a discharging mode, and a protection mode. That is to say, Figure 10 The power supply circuit 1 shown can realize the pre-charging, charging, discharging, and protection of the energy storage unit. The pre-charging, charging, discharging, and protection of the energy storage unit through the power supply circuit 1 are described below.

[0156] (1) Pre-charging

[0157] In the pre-charging mode, the first switching unit 101 is in the on state and the second switching unit 102 is in the off state. Therefore, when the first switching unit 101 is on and the real-time DC voltage of the energy storage unit ESU is lower than the first DC voltage, the power supply circuit 1 can control the DC-DC converter unit DCTU to turn off, the fourth switching unit 104 to close and the third switching unit 103 to turn on, and supply the first DC voltage to the energy storage unit ESU through the fourth switching unit 104, the third switching unit 103 and the first switching unit 101 to realize the pre-charging of the energy storage unit ESU.

[0158] The direction and path of current flow can be as follows Figure 11 As shown, the current output by the DC power supply DCPS can pass through the fourth switch unit 104, the third switch unit 103, the first switch unit 101 and the lithium battery B1 in sequence, and finally return to the DC power supply DCPS to form a complete loop, thereby realizing the pre-charging of the lithium battery B1.

[0159] (2) Charging

[0160] Based on the relationship between the terminal voltage of lithium battery B1 and the DC voltage output by DC power supply DCPS (i.e., the first DC voltage), the charging of energy storage unit ESU by power supply circuit 1 can be divided into the following two cases:

[0161] Scenario 1: When the terminal voltage of lithium battery B1 is equal to the DC voltage output by DC power supply DCPS, power supply circuit 1 can charge lithium battery B1 through the following three methods:

[0162] Method 1: The first switching unit 101 is in the on state. When the first switching unit 101 is on and the real-time DC voltage of the energy storage unit ESU is equal to the first DC voltage, the power supply circuit 1 can control the DC-DC converter unit DCTU to turn off, the fourth switching unit 104 to open, the third switching unit 103 to turn off and the second switching unit 102 to close, and supply the first DC voltage to the energy storage unit ESU through the second switching unit 102 and the first switching unit 101.

[0163] The direction and path of current flow can be Figure 12 In the circuit L1, the current output by the DC power supply DCPS can pass through the second switching unit 102, the first switching unit 101 and the lithium battery B1 in sequence, and finally return to the DC power supply DCPS to form a complete circuit and realize the charging of the lithium battery B1.

[0164] Method 2: When the first switching unit 101 is in the on state, the power supply circuit 1 can control the DC-DC converter unit DCTU to be turned off, the second switching unit to be turned off, the fourth switching unit 104 to be turned on and the third switching unit 103 to be turned on, and the first DC voltage is supplied to the energy storage unit ESU through the fourth switching unit 104, the third switching unit 103 and the first switching unit 101.

[0165] The direction and path of current flow can be Figure 12 In L2, the current output by the DC power supply DCPS can pass through the fourth switch unit 104, the third switch unit 103, the first switch unit 101 and the lithium battery B1 in sequence, and finally return to the DC power supply DCPS to form a complete circuit and realize the charging of the lithium battery B1.

[0166] Method 3: With the first switching unit 101 in the ON state, the power supply circuit 1 can control the DC-DC converter (DCTU) to OFF, the fourth switching unit 104 to OFF, the third switching unit 103 to OFF, and the second switching unit 102 to OFF. The power supply circuit 1 can supply the first DC voltage to the energy storage unit (ESU) not only through the second switching unit 102 and the first switching unit 101, but also through the fourth switching unit 104, the third switching unit 103, and the first switching unit 101.

[0167] The direction and path of current flow can be Figure 12 The L1 and L2 paths represent two possible current paths. Path L1 shows the current output from the DC power supply (DCPS) passing sequentially through the second switching unit 102, the first switching unit 101, and the lithium battery B1, before returning to the DC power supply (DCPS). Path L2 shows the current output from the DC power supply (DCPS) passing sequentially through the fourth switching unit 104, the third switching unit 103, the first switching unit 101, and the lithium battery B1, before returning to the DC power supply (DCPS). Both L1 and L2 can form a complete circuit, thus enabling the charging of the lithium battery B1.

[0168] Scenario 2: When the terminal voltage of lithium battery B1 is less than the DC voltage output by DC power supply DCPS (i.e., the voltage difference between the DC voltage output by DC power supply DCPS and the terminal voltage of lithium battery B1 is large), power supply circuit 1 can control DC converter unit DCTU to open, fourth switch unit 104 to close and first switch unit 101 to conduct, and transmit the first DC voltage to energy storage unit ESU through fourth switch unit 104, DC converter unit DCTU and first switch unit 101.

[0169] Understandably, the DC-DC converter (DCTU) lowers the first DC voltage, which means it lowers the output voltage of the DCTU. Since the output voltage and output current of the DCTU are directly proportional, the output current of the DCTU also decreases. Furthermore, since the charging current of lithium battery B1 is equal to the output current of the DCTU, the charging current of lithium battery B1 also decreases. Therefore, the DCTU enables current-limited charging of lithium battery B1, preventing damage to it.

[0170] The direction and path of current flow can be as follows Figure 13 As shown, the current output from the DC power supply DCPS can sequentially pass through the fourth switching unit 104, the DC-DC converter unit DCTU, and the lithium battery B1, finally returning to the DC power supply DCPS. This can also form a complete circuit to charge the lithium battery B1.

[0171] (3) Discharge

[0172] If the rated voltage of the load unit LU is greater than the DC voltage output by the DC power supply DCPS, the load unit LU can be discharged through the lithium battery B1 to ensure normal operation.

[0173] In one example, power supply circuit 1 can control the DC-DC converter unit (DCTU) to shut down, the fourth switch unit 104 to open, the third switch unit 103 to turn off, the second switch unit 102 to close, and the first switch unit 101 to turn on. Power supply circuit 1 provides the real-time DC voltage of the energy storage unit (ESU) to the load unit (LU) through the first switch unit 101 and the second switch unit 102.

[0174] The direction and path of current flow can be as follows Figure 14 In the circuit L1, the discharge current of lithium battery B1 can pass through the first switching unit 101, the second switching unit 102 and the load unit LU in sequence, and finally return to lithium battery B1 to form a complete circuit and realize the discharge of lithium battery B1.

[0175] In another example, power supply circuit 1 can control the DC-DC converter unit (DCTU) to turn off, the second switch unit 102 to open, the fourth switch unit 104 to close, the third switch unit 103 to turn on, and the first switch unit 101 to turn on in sequence. The real-time DC voltage of the energy storage unit (ESU) is provided to the load unit (LU) through the first switch unit 101, the third switch unit 103, and the fourth switch unit 104.

[0176] The direction and path of current flow can be as follows Figure 14In L2, the discharge current of lithium battery B1 can pass through the first switch unit 101, the third switch unit 103, the fourth switch unit 104 and the load unit LU in sequence, and finally return to lithium battery B1 to form a complete circuit and realize the discharge of lithium battery B1.

[0177] In another example, the power supply circuit 1 can control the DC-DC converter unit (DCTU) to be turned off, the fourth switch unit 104 to be closed, the third switch unit 103 to be turned on, the second switch unit 102 to be closed, and the first switch unit 101 to be turned on. The real-time DC voltage of the energy storage unit (ESU) is transmitted to the load unit (LU) through the first switch unit 101 and the second switch unit 102. The real-time DC voltage of the energy storage unit (ESU) is also provided to the load unit (LU) through the first switch unit 101, the third switch unit 103, and the fourth switch unit 104.

[0178] The direction and path of current flow can be as follows Figure 14 In the diagram, paths L1 and L2 (i.e., two paths) allow the discharge current of lithium battery B1 to not only pass through the first switching unit 101, the second switching unit 102, and the load unit LU in sequence, forming a complete loop, but also pass through the first switching unit 101, the third switching unit 103, the fourth switching unit 104, and the load unit LU in sequence, finally returning to lithium battery B1. It can be seen that both paths can achieve the discharge of lithium battery B1.

[0179] It should be noted that when the voltage of the load unit LU is less than the DC voltage output by the DC power supply DCPS, the load unit LU can be powered by the DC power supply DCPS. The lithium battery B1 does not need to be discharged, and the second switching unit 102 can be disconnected to reduce the energy consumption of the power supply circuit 1.

[0180] The power supply circuit provided in this application adopts a hybrid topology of MOSFETs and relays, which can achieve the discharge of the energy storage unit ESU through only the first and second switching units, or only the third and fourth switching units. It can be seen that during the discharge process of the energy storage unit ESU, it is not necessary for all four switching units to be closed (or turned on), which can reduce the overall loss and heat generation of the power supply circuit and improve its reliability.

[0181] (4) Protection

[0182] In one possible implementation, when the discharge current of the lithium battery B1 exceeds a preset current threshold, the first switching unit 101 can be directly shut down, thereby protecting the load unit LU and the power supply circuit 1.

[0183] In another possible implementation, when the charging current of lithium battery B1 exceeds a preset current threshold (i.e., lithium battery B1 is overcurrent), since the first switching unit 101 is in the on state and the second switching unit 102 is in the closed state, the power supply circuit 1 can control the fourth switching unit 104 to close, the third switching unit 103 to turn on, and control the second switching unit 102 to open and the third switching unit 103 to turn off, thereby achieving protection for the power supply circuit 1 and lithium battery B1.

[0184] This application also provides another power supply circuit, such as... Figure 15 As shown. With Figure 2 The power supply circuits shown are the same. Figure 15 In the power supply circuit 1 shown, the main control unit 10 may also include a first switch unit 101 and a second switch unit 102, and the auxiliary control unit 20 may also include a third switch unit 103 and a fourth switch unit 104.

[0185] and Figure 2 The difference is, Figure 15 The position of the first switching unit 101 is different. The first end of the first switching unit 101 (e.g., ...) Figure 15 The left end of the first switching unit 101 can be connected to the second end of the energy storage unit ESU (such as...). Figure 15 The lower end of the energy storage unit ESU can be connected to the negative terminal of the energy storage unit ESU, and the second end of the first switching unit 101 (such as...) Figure 15 The right end of the first switching unit 101 can be connected to node F, and node F can then be connected to the second end of the load unit LU (which can be the negative terminal of the load unit LU, such as...). Figure 15 The lower end of the medium load unit LU) is connected to the first end of the energy storage unit ESU (such as...). Figure 15 The upper end of the energy storage unit ESU can be the positive terminal of the energy storage unit ESU), and the first terminal of the second switching unit 102 (such as...) Figure 15 The left end of the second switching unit 102 and the first end of the third switching unit 103 (as shown in the image) Figure 15 The left end of the third switch unit 103 can be connected to node A, and the second end of the second switch unit 102 (such as...) Figure 15 The right end of the second switch unit 102 is connected to node B, and the second end of the third switch unit 103 (as shown in the image) is connected to node B. Figure 15 The right end of the third switch unit 103 and the second end of the fourth switch unit 104 (as shown in the image) Figure 15 The lower end of the fourth switch unit 104 is connected, and the first end of the fourth switch unit 104 (such as...) Figure 15 The upper end of the fourth switching unit 104 is connected to node B. Node B and the first terminal of the DC power supply DCPS can be the positive terminal of the DC power supply DCPS, such as... Figure 15 The upper end of the DC power supply (DCPS) can be connected to the first end of the load unit LU (which can be the positive terminal of the load unit LU, such as...) through node E. Figure 15 The upper end of the medium load unit LU is connected to the second terminal of the DC power supply DCPS (which can be the negative terminal of the DC power supply DCPS, such as...). Figure 15 The lower end of the DC power supply (DCPS) can be connected to the second end of the load unit LU (which can be the negative terminal of the load unit LU, such as...) through node F. Figure 15 (Connect to the lower end of the load unit LU).

[0186] In one possible implementation, the embodiments of this application provide, as follows: Figure 15 The power supply circuit 1 shown may also include a DC-DC converter unit (DCTU).

[0187] Since the DC-DC converter unit (DCTU) only needs to participate in the charging of the energy storage unit (ESU) and does not participate in the discharging of the ESU, it can be considered that the DC-DC converter unit (DCTU) will only be turned on during the charging process of the ESU and will be turned off during the discharging process of the ESU.

[0188] Therefore, in one example, such as Figure 16 As shown, the first terminal of the DC-DC converter (DCTU) can be the input terminal of the DC-DC converter, such as... Figure 16 The right end of the DC-DC converter unit (DCTU) can be connected to node D (i.e., Figure 16 The node between the third switching unit 103 and the fourth switching unit 104, and the second terminal of the DC-DC converter (which can be the output terminal of the DC-DC converter, such as...) Figure 16 The left end of the DC-DC converter unit (DCTU) can be connected to node A (it can be considered that the output of the DCTU is connected to node C, and node C is then connected to node A). The third end of the DCTU (can be the reference ground of the DCTU, such as...) Figure 16 The lower end of the DC-DC converter unit (DCTU) can be connected to the second end of the first switching unit 101, and the first end of the first switching unit 101 is connected to the second end of the energy storage unit ESU. Simultaneously, the third end of the DC-DC converter unit (DCTU) can be connected to the second end of the load unit LU via node F.

[0189] In other words, the reference ground terminal of the DC-DC converter unit (DCTU), the second terminal of the first switching unit 101, and the negative terminal of the load unit LU can be connected to node F, and node F is then connected to the reference ground. Alternatively, the DC-DC converter unit (DCTU), the first switching unit 101, and the load unit LU can share a common ground.

[0190] In one possible implementation, Figure 16 In the power supply circuit 1 shown, the first switching unit 101 may include a power switch or a plurality of power switches connected in parallel.

[0191] Similarly, the third switching unit 103 may also include a power switch or multiple power switches connected in parallel.

[0192] Furthermore, the power switch is a MOSFET or an IGBT. Of course, the power switch can also be other power transistors, and this application embodiment is not limited to them.

[0193] In another possible implementation Figure 16 In the power supply circuit 1 shown, the second switching unit 102 may include one mechanical switch or multiple mechanical switches. In the scenario where the second switching unit 102 includes multiple mechanical switches, the multiple mechanical switches may be connected in series, in parallel, or in a combination of series and parallel.

[0194] Similarly, the fourth switching unit 104 may include one mechanical switch or multiple mechanical switches. In the scenario where the fourth switching unit 104 includes multiple mechanical switches, the multiple mechanical switches may be connected in series, in parallel, or in a combination of series and parallel.

[0195] Furthermore, the mechanical switch can be any one of a relay, contactor, and circuit breaker. Of course, the mechanical switch can also be other types, which are not limited in the embodiments of this application.

[0196] This application embodiment uses the energy storage unit ESU as the lithium battery B1, and exemplifies the following: the first switching unit 101 and the third switching unit 103 each include a MOSFET, and the second switching unit 102 and the fourth switching unit 104 each include a relay. Figure 17 As shown.

[0197] refer to Figure 17 The drain of the first switching unit 101 can be connected to the negative terminal of the lithium battery B1, and the source of the first switching unit 101 can be connected to node F. Node F is then connected to the negative terminal of the load unit LU. The positive terminal of the lithium battery B1 and the first terminal of the second switching unit 102 can be connected to node A, respectively. The first terminal of the third switching unit 103 can be connected to node C, and node C can be connected to node A. The second terminal of the second switching unit 102 is connected to node B. The second terminals of the third switching unit 103 and the fourth switching unit 104 are connected to node D, respectively. The first terminal of the fourth switching unit 104 is connected to node B, and node B can be connected to the positive terminal of the load unit LU.

[0198] The first terminal of the DC-DC converter unit (DCTU) is connected to node D, the second terminal of the DC-DC converter unit (DCTU) can be connected to node C, and the reference ground terminal of the DC-DC converter unit (DCTU) can be connected to the source of the first switching unit 101. Simultaneously, the reference ground terminal of the DC-DC converter unit (DCTU) can be connected to the negative terminal of the load unit LU through node F.

[0199] Figure 17 The reference ground terminal of the DC-DC converter unit (DCTU), the source terminal of the first switching unit 101, and the negative terminal of the load unit LU can also be connected to node F, and node F is then connected to the reference ground. Alternatively, it can be considered that... Figure 17 The DC-DC converter unit (DCTU), the first switching unit (101), and the load unit (LU) can share a common ground.

[0200] Optionally, the positive terminal of the DC power supply DCPS can be connected to the positive terminal of the load unit LU through node E, and the negative terminal of the DC power supply DCPS can be connected to the negative terminal of the load unit LU through node F.

[0201] Optionally, in practical application scenarios, Figure 17 The power supply circuit 1 shown can have a pre-charge mode, a charging mode, a discharging mode, and a protection mode. That is to say, Figure 17 The power supply circuit 1 shown can realize the pre-charging, charging, discharging, and protection of the energy storage unit. The following describes the pre-charging, charging, discharging, and protection of the energy storage unit through the power supply circuit 1.

[0202] (1) Pre-charging

[0203] In the pre-charging mode, the first switching unit 101 is in the on state and the second switching unit 102 is in the off state. Therefore, when the first switching unit 101 is on and the real-time DC voltage of the energy storage unit ESU is lower than the first DC voltage, the power supply circuit 1 can control the DC-DC converter unit DCTU to turn off, the fourth switching unit 104 to close and the third switching unit 103 to turn on, and supply the first DC voltage to the energy storage unit ESU through the fourth switching unit 104, the third switching unit 103 and the first switching unit 101 to realize the pre-charging of the energy storage unit ESU.

[0204] The direction and path of current flow can be as follows Figure 18 As shown, the current output by the DC power supply DCPS can pass through the fourth switch unit 104, the third switch unit 103, the lithium battery B1 and the first switch unit 101 in sequence, and finally return to the DC power supply DCPS to form a complete loop, thereby realizing the pre-charging of the lithium battery B1.

[0205] (2) Charging

[0206] Based on the relationship between the terminal voltage of lithium battery B1 and the DC voltage output by DC power supply DCPS (i.e., the first DC voltage), the charging of energy storage unit ESU by power supply circuit 1 can be divided into the following two cases:

[0207] Scenario 1: When the terminal voltage of lithium battery B1 is equal to the DC voltage output by DC power supply DCPS, power supply circuit 1 can charge lithium battery B1 through the following three methods:

[0208] Method 1: When the first switching unit 101 is in the on state, the power supply circuit 1 can control the DC-DC converter unit DCTU to turn off, the fourth switching unit 104 to open, the third switching unit 103 to turn off and the second switching unit 102 to close, and the first DC voltage is supplied to the energy storage unit ESU through the second switching unit 102 and the first switching unit 101.

[0209] The direction and path of current flow can be Figure 19 In the circuit L1, the current output by the DC power supply DCPS can pass through the second switching unit 102, the lithium battery B1 and the first switching unit 101 in sequence, and finally return to the DC power supply DCPS to form a complete circuit and realize the charging of the lithium battery B1.

[0210] Method 2: When the first switching unit 101 is in the on state, the power supply circuit 1 can control the DC-DC converter unit DCTU to be turned off, the second switching unit to be turned off, the fourth switching unit 104 to be turned on and the third switching unit 103 to be turned on, and the first DC voltage is supplied to the energy storage unit ESU through the fourth switching unit 104, the third switching unit 103 and the first switching unit 101.

[0211] The direction and path of current flow can be Figure 19 In L2, the current output by the DC power supply DCPS can pass through the fourth switch unit 104, the third switch unit 103, the lithium battery B1 and the first switch unit 101 in sequence, and finally return to the DC power supply DCPS to form a complete circuit and realize the charging of the lithium battery B1.

[0212] Method 3: With the first switching unit 101 in the ON state, the power supply circuit 1 can control the DC-DC converter (DCTU) to OFF, the fourth switching unit 104 to OFF, the third switching unit 103 to OFF, and the second switching unit 102 to OFF. The power supply circuit 1 can supply the first DC voltage to the energy storage unit (ESU) not only through the second switching unit 102 and the first switching unit 101, but also through the fourth switching unit 104, the third switching unit 103, and the first switching unit 101.

[0213] The direction and path of current flow can be Figure 19The L1 and L2 paths represent two possible current paths. Path L1 involves the current output from the DC power supply (DCPS) passing sequentially through the second switching unit 102, the lithium battery B1, and the first switching unit 101, before returning to the DC power supply (DCPS). Path L2 involves the current output from the DC power supply (DCPS) passing sequentially through the fourth switching unit 104, the third switching unit 103, the lithium battery B1, and the first switching unit 101, before returning to the DC power supply (DCPS). Both L1 and L2 can form a complete circuit, thus enabling the charging of the lithium battery B1.

[0214] Scenario 2: When the terminal voltage of lithium battery B1 is less than the DC voltage output by DC power supply DCPS (i.e., the voltage difference between the DC voltage output by DC power supply DCPS and the terminal voltage of lithium battery B1 is large), power supply circuit 1 can control DC converter unit DCTU to open, fourth switch unit 104 to close and first switch unit 101 to conduct, and provide the first DC voltage to energy storage unit ESU through fourth switch unit 104, DC converter unit DCTU and first switch unit 101.

[0215] Understandably, the DC-DC converter (DCTU) lowers the first DC voltage, which means it lowers the output voltage of the DCTU. Since the output voltage and output current of the DCTU are directly proportional, the output current of the DCTU also decreases. Furthermore, since the charging current of lithium battery B1 is equal to the output current of the DCTU, the charging current of lithium battery B1 also decreases. Therefore, the DCTU enables current-limited charging of lithium battery B1, preventing damage to it.

[0216] The direction and path of current flow can be as follows Figure 20 As shown, the current output from the DC power supply DCPS can sequentially pass through the fourth switching unit 104, the DC-DC converter unit DCTU, the lithium battery B1, and the first switching unit 101, finally returning to the DC power supply DCPS. This can also form a complete circuit to charge the lithium battery B1.

[0217] (3) Discharge

[0218] If the rated voltage of the load unit LU is greater than the DC voltage output by the DC power supply DCPS, the load unit LU can be discharged through the lithium battery B1 to ensure normal operation.

[0219] In one example, power supply circuit 1 can control the DC-DC converter unit (DCTU) to shut down, the fourth switch unit 104 to open, the third switch unit 103 to turn off, and control the second switch unit 102 to close and the first switch unit 101 to turn on. Power supply circuit 1 provides the real-time DC voltage of the energy storage unit (ESU) to the load unit (LU) through the first switch unit 101 and the second switch unit 102.

[0220] The direction and path of current flow can be as follows Figure 21 In the circuit L1, the discharge current of lithium battery B1 can pass through the second switching unit 102, the load unit LU and the first switching unit 101 in sequence, and finally return to lithium battery B1 to form a complete circuit and realize the discharge of lithium battery B1.

[0221] In another example, power supply circuit 1 can control the DC-DC converter unit (DCTU) to turn off, the second switch unit 102 to open, the fourth switch unit 104 to close, the third switch unit 103 to turn on, and the first switch unit 101 to turn on. The real-time DC voltage of the energy storage unit (ESU) is provided to the load unit (LU) through the first switch unit 101, the third switch unit 103, and the fourth switch unit 104.

[0222] The direction and path of current flow can be as follows Figure 21 In L2, the discharge current of lithium battery B1 can pass through the third switch unit 103, the fourth switch unit 104, the load unit LU and the first switch unit 101 in sequence, and finally return to lithium battery B1 to form a complete circuit and realize the discharge of lithium battery B1.

[0223] In another example, the power supply circuit 1 can control the DC-DC converter unit (DCTU) to turn off, the fourth switch unit 104 to close, the third switch unit 103 to turn on, and the second switch unit 102 and the first switch unit 101 to turn on. The real-time DC voltage of the energy storage unit (ESU) is transmitted to the load unit (LU) through the first switch unit 101 and the second switch unit 102. The real-time DC voltage of the energy storage unit (ESU) is also provided to the load unit (LU) through the first switch unit 101, the third switch unit 103 and the fourth switch unit 104.

[0224] The direction and path of current flow can be as follows Figure 21 In the diagram, paths L1 and L2 (i.e., two paths) allow the discharge current of lithium battery B1 to not only pass through the second switching unit 102, load unit LU, and first switching unit 101 in sequence, finally returning to lithium battery B1 to form a complete loop, but also through the third switching unit 103, fourth switching unit 104, load unit LU, and first switching unit 101 in sequence, finally returning to lithium battery B1. It can be seen that both paths can achieve the discharge of lithium battery B1.

[0225] It should be noted that when the voltage of the load unit LU is less than the DC voltage output by the DC power supply DCPS, the load unit LU can be powered by the DC power supply DCPS. The lithium battery B1 does not need to be discharged, and the second switching unit 102 can be disconnected to reduce the energy consumption of the power supply circuit 1.

[0226] The power supply circuit provided in this application adopts a hybrid topology of MOSFETs and relays, which can achieve the discharge of the energy storage unit ESU through only the first and second switching units, or only the third and fourth switching units. It can be seen that during the discharge process of the energy storage unit ESU, it is not necessary for all four switching units to be closed (or turned on), which can reduce the overall loss and heat generation of the power supply circuit and improve its reliability.

[0227] (4) Protection

[0228] In one possible implementation, when the discharge current of the lithium battery B1 exceeds a preset current threshold, the first switching unit 101 can be directly shut down, thereby protecting the load unit LU and the power supply circuit 1.

[0229] In another possible implementation, when the charging current of lithium battery B1 exceeds a preset current threshold (i.e., lithium battery B1 is overcharged), since the first switching unit 101 is in the on state and the second switching unit 102 is in the closed state, the power supply circuit 1 can control the fourth switching unit 104 to close, the third switching unit 103 to turn on, the second switching unit 102 to open, and the third switching unit 103 to turn off, thereby achieving protection for the power supply circuit 1 and lithium battery B1.

[0230] This application also provides another power supply circuit, such as... Figure 22 As shown. With Figure 16 The power supply circuits shown are the same. Figure 22 In the power supply circuit 1 shown, the main control unit 10 ( Figure 22 (Not shown in the text) may also include a first switching unit 101 and a second switching unit 102, and an auxiliary control unit 20 ( Figure 22 (Not shown in the text) It may also include a third switch unit 103 and a fourth switch unit 104.

[0231] and Figure 16 The difference is, Figure 22 The position of the first switching unit 101 is different. The first end of the first switching unit 101 (e.g., ...) Figure 22 The left end of the first switching unit 101 can be connected to the second end of the energy storage unit ESU (such as...). Figure 22The lower end of the energy storage unit ESU can be connected to the negative terminal of the energy storage unit ESU, and the second end of the first switching unit 101 (such as...) Figure 22 The right end of the first switching unit 101 can be connected to node F, and node F can then be connected to the second end of the load unit LU (which can be the negative terminal of the load unit LU, such as...). Figure 22 The lower end of the medium load unit LU) is connected to the first end of the energy storage unit ESU (such as...). Figure 22 The upper end of the energy storage unit ESU can be the positive terminal of the energy storage unit ESU), and the first terminal of the second switching unit 102 (such as...) Figure 22 The left end of the second switching unit 102 and the first end of the third switching unit 103 (as shown in the image) Figure 22 The left end of the third switch unit 103 can be connected to node A, and the second end of the second switch unit 102 (such as...) Figure 22 The right end of the second switch unit 102 is connected to node B, and the second end of the third switch unit 103 (as shown in the image) is connected to node B. Figure 22 The right end of the third switch unit 103 and the second end of the fourth switch unit 104 (as shown in the image) Figure 22 The lower end of the fourth switch unit 104 is connected, and the first end of the fourth switch unit 104 (such as...) Figure 22 The upper end of the fourth switching unit 104 is connected to node B, and node B can be connected to the first end of the load unit LU (which can be the positive terminal of the load unit LU, such as...). Figure 22 The upper end of the load unit LU is connected.

[0232] In one possible implementation, the embodiments of this application Figure 22 The power supply circuit 1 shown may also include a DC-DC converter unit (DCTU).

[0233] Since the DC-DC converter unit (DCTU) only needs to participate in the charging of the energy storage unit (ESU) and does not participate in the discharging of the ESU, it can be considered that the DC-DC converter unit (DCTU) will only be turned on during the charging process of the ESU and will be turned off during the discharging process of the ESU.

[0234] Therefore, in one example, such as Figure 22 As shown, the first terminal of the DC-DC converter (DCTU) can be the input terminal of the DC-DC converter, such as... Figure 22 The right end of the DC-DC converter unit (DCTU) can be connected to node D (i.e., Figure 22 The node between the third switching unit 103 and the fourth switching unit 104, and the second terminal of the DC-DC converter (which can be the output terminal of the DC-DC converter, such as...) Figure 22The left end of the DC-DC converter unit (DCTU) can be connected to node A (it can be considered that the output of the DCTU is connected to node C, and node C is then connected to node A). The third end of the DCTU (can be the reference ground of the DCTU, such as...) Figure 22 The lower end of the DC-DC converter unit (DCTU) can be connected to the first end of the first switching unit 101 and the second end of the energy storage unit ESU. The second end of the first switching unit 101 can be connected to the second end of the load unit LU through node F.

[0235] In other words, the second terminal of the first switching unit 101 and the negative terminal of the load unit LU can be connected to node F, and node F is then connected to the reference ground. Alternatively, the first switching unit 101 and the load unit LU can share a common ground.

[0236] In one possible implementation, Figure 22 In the power supply circuit 1 shown, the first switching unit 101 may include a power switch or a plurality of power switches connected in parallel.

[0237] Similarly, the third switching unit 103 may also include a power switch or multiple power switches connected in parallel.

[0238] Furthermore, the power switch is a MOSFET or an IGBT. Of course, the power switch can also be other power transistors, and this application embodiment is not limited to them.

[0239] In another possible implementation Figure 22 In the power supply circuit 1 shown, the second switching unit 102 may include one mechanical switch or multiple mechanical switches. In the scenario where the second switching unit 102 includes multiple mechanical switches, the multiple mechanical switches may be connected in series, in parallel, or in a combination of series and parallel.

[0240] Similarly, the fourth switching unit 104 may include one mechanical switch or multiple mechanical switches. In the scenario where the fourth switching unit 104 includes multiple mechanical switches, the multiple mechanical switches may be connected in series, in parallel, or in a combination of series and parallel.

[0241] Furthermore, the mechanical switch can be any one of a relay, contactor, and circuit breaker. Of course, the mechanical switch can also be other types, which are not limited in the embodiments of this application.

[0242] This application embodiment uses the energy storage unit ESU as the lithium battery B1, and exemplifies the following: the first switching unit 101 and the third switching unit 103 each include a MOSFET, and the second switching unit 102 and the fourth switching unit 104 each include a relay. Figure 23 As shown.

[0243] refer to Figure 23 The drain of the first switching unit 101 can be connected to the negative terminal of the lithium battery B1, and the source of the first switching unit 101 can be connected to node F. Node F is then connected to the negative terminal of the load unit LU. The positive terminal of the lithium battery B1 and the first terminal of the second switching unit 102 can be connected to node A, respectively. The source of the third switching unit 103 can be connected to node C, and node C is connected to node A. The second terminal of the second switching unit 102 is connected to node B. The drain of the third switching unit 103 and the second terminal of the fourth switching unit 104 are respectively connected to node D. The first terminal of the fourth switching unit 104 is connected to node B, and node B can be connected to the positive terminal of the load unit LU.

[0244] The first terminal of the DC-DC converter unit (DCTU) is connected to node D, and the second terminal of the DC-DC converter unit (DCTU) can be connected to node C. The reference ground terminal of the DC-DC converter unit (DCTU) can be connected to the drain of the first switching unit 101 and the negative terminal of the lithium battery B1. Simultaneously, the source of the first switching unit 101 can be connected to the negative terminal of the load unit LU through node F.

[0245] Optionally, the positive terminal of the DC power supply DCPS can be connected to the positive terminal of the load unit LU through node E, and the negative terminal of the DC power supply DCPS can be connected to the negative terminal of the load unit LU through node F.

[0246] Optionally, in practical application scenarios, Figure 22 The power supply circuit 1 shown can have a pre-charge mode, a charging mode, a discharging mode, and a protection mode. That is to say, Figure 22 The power supply circuit 1 shown can realize the pre-charging, charging, discharging, and protection of the energy storage unit. The following describes the pre-charging, charging, discharging, and protection of the energy storage unit through the power supply circuit 1.

[0247] (1) Pre-charging

[0248] In the pre-charging mode, the first switching unit 101 is in the on state and the second switching unit 102 is in the off state. The power supply circuit 1 can control the DC-DC converter unit (DCTU) to turn off, the fourth switching unit 104 to close and the third switching unit 103 to turn on, and provide the first DC voltage to the energy storage unit (ESU) through the fourth switching unit 104, the third switching unit 103 and the first switching unit 101 to realize the pre-charging of the energy storage unit (ESU).

[0249] The direction and path of current flow can be as follows Figure 24As shown, the current output by the DC power supply DCPS can pass through the fourth switch unit 104, the third switch unit 103, the lithium battery B1 and the first switch unit 101 in sequence, and finally return to the DC power supply DCPS to form a complete loop, thereby realizing the pre-charging of the lithium battery B1.

[0250] (2) Charging

[0251] Based on the relationship between the terminal voltage of lithium battery B1 and the DC voltage output by DC power supply DCPS (i.e., the first DC voltage), the charging of energy storage unit ESU by power supply circuit 1 can be divided into the following two cases:

[0252] Scenario 1: When the terminal voltage of lithium battery B1 is equal to the DC voltage output by DC power supply DCPS, power supply circuit 1 can charge lithium battery B1 through the following three methods:

[0253] Method 1: When the first switching unit 101 is in the on state, the power supply circuit 1 can control the DC-DC converter unit DCTU to turn off, the fourth switching unit 104 to open, the third switching unit 103 to turn off and the second switching unit 102 to close, and the first DC voltage is supplied to the energy storage unit ESU through the second switching unit 102 and the first switching unit 101.

[0254] The direction and path of current flow can be Figure 25 In the circuit L1, the current output by the DC power supply DCPS can pass through the second switching unit 102, the lithium battery B1 and the first switching unit 101 in sequence, and finally return to the DC power supply DCPS to form a complete circuit and realize the charging of the lithium battery B1.

[0255] Method 2: When the first switching unit 101 is in the on state, the power supply circuit 1 can control the DC-DC converter unit DCTU to be turned off, the second switching unit to be turned off, the fourth switching unit 104 to be turned on and the third switching unit 103 to be turned on, and the first DC voltage is supplied to the energy storage unit ESU through the fourth switching unit 104, the third switching unit 103 and the first switching unit 101.

[0256] The direction and path of current flow can be Figure 25 In L2, the current output by the DC power supply DCPS can pass through the fourth switch unit 104, the third switch unit 103, the lithium battery B1 and the first switch unit 101 in sequence, and finally return to the DC power supply DCPS to form a complete circuit and realize the charging of the lithium battery B1.

[0257] Method 3: With the first switching unit 101 in the ON state, the power supply circuit 1 can control the DC-DC converter (DCTU) to OFF, the fourth switching unit 104 to OFF, the third switching unit 103 to OFF, and the second switching unit 102 to OFF. The power supply circuit 1 can supply the first DC voltage to the energy storage unit (ESU) not only through the second switching unit 102 and the first switching unit 101, but also through the fourth switching unit 104, the third switching unit 103, and the first switching unit 101.

[0258] The direction and path of current flow can be Figure 25 The L1 and L2 paths represent two possible current paths. Path L1 involves the current output from the DC power supply (DCPS) passing sequentially through the second switching unit 102, the lithium battery B1, and the first switching unit 101, before returning to the DC power supply (DCPS). Path L2 involves the current output from the DC power supply (DCPS) passing sequentially through the fourth switching unit 104, the third switching unit 103, the lithium battery B1, and the first switching unit 101, before returning to the DC power supply (DCPS). Both L1 and L2 can form a complete circuit, thus enabling the charging of the lithium battery B1.

[0259] Scenario 2: When the terminal voltage of lithium battery B1 is less than the DC voltage output by DC power supply DCPS (i.e., the voltage difference between the DC voltage output by DC power supply DCPS and the terminal voltage of lithium battery B1 is large), power supply circuit 1 can control DC converter unit DCTU to open, fourth switch unit 104 to close and first switch unit 101 to conduct, and provide the first DC voltage to energy storage unit ESU through fourth switch unit 104, DC converter unit DCTU and first switch unit 101.

[0260] Understandably, the DC-DC converter (DCTU) lowers the first DC voltage, which means it lowers the output voltage of the DCTU. Since the output voltage and output current of the DCTU are directly proportional, the output current of the DCTU also decreases. Furthermore, since the charging current of lithium battery B1 is equal to the output current of the DCTU, the charging current of lithium battery B1 also decreases. Therefore, the DCTU enables current-limited charging of lithium battery B1, preventing damage to it.

[0261] The direction and path of current flow can be as follows Figure 26 As shown, the current output from the DC power supply DCPS can sequentially pass through the fourth switching unit 104, the DC-DC converter unit DCTU, the lithium battery B1, and the first switching unit 101, finally returning to the DC power supply DCPS. This can also form a complete circuit to charge the lithium battery B1.

[0262] (3) Discharge

[0263] If the rated voltage of the load unit LU is greater than the DC voltage output by the DC power supply DCPS, the load unit LU can be discharged through the lithium battery B1 to ensure normal operation.

[0264] In one example, the power supply circuit 1 can control the DC-DC converter unit (DCTU) to turn off, the fourth switch unit 104 to open, the third switch unit 103 to turn off, and can also control the second switch unit 102 to close and the first switch unit 101 to turn on. The power supply circuit 1 provides the real-time DC voltage of the energy storage unit (ESU) to the load unit (LU) through the first switch unit 101 and the second switch unit 102.

[0265] The direction and path of current flow can be as follows Figure 27 In the circuit L1, the discharge current of lithium battery B1 can pass through the second switching unit 102, the load unit LU and the first switching unit 101 in sequence, and finally return to lithium battery B1 to form a complete circuit and realize the discharge of lithium battery B1.

[0266] In another example, power supply circuit 1 can control the DC-DC converter unit (DCTU) to turn off, the second switch unit 102 to open, the fourth switch unit 104 to close, the third switch unit 103 to turn on, and the first switch unit 101 to turn on. The real-time DC voltage of the energy storage unit (ESU) is provided to the load unit (LU) through the first switch unit 101, the third switch unit 103, and the fourth switch unit 104.

[0267] The direction and path of current flow can be as follows Figure 27 In L2, the discharge current of lithium battery B1 can pass through the third switch unit 103, the fourth switch unit 104, the load unit LU and the first switch unit 101 in sequence, and finally return to lithium battery B1 to form a complete circuit and realize the discharge of lithium battery B1.

[0268] In another example, the power supply circuit 1 can control the DC-DC converter unit (DCTU) to turn off, the fourth switch unit 104 to close, the third switch unit 103 to turn on, and the second switch unit 102 and the first switch unit 101 to turn on. The real-time DC voltage of the energy storage unit (ESU) is transmitted to the load unit (LU) through the first switch unit 101 and the second switch unit 102. The real-time DC voltage of the energy storage unit (ESU) is also provided to the load unit (LU) through the first switch unit 101, the third switch unit 103 and the fourth switch unit 104.

[0269] The direction and path of current flow can be as follows Figure 27In the diagram, paths L1 and L2 (i.e., two paths) allow the discharge current of lithium battery B1 to not only pass through the second switching unit 102, load unit LU, and first switching unit 101 in sequence, finally returning to lithium battery B1 to form a complete loop, but also through the third switching unit 103, fourth switching unit 104, load unit LU, and first switching unit 101 in sequence, finally returning to lithium battery B1. It can be seen that both paths can achieve the discharge of lithium battery B1.

[0270] It should be noted that when the voltage of the load unit LU is less than the DC voltage output by the DC power supply DCPS, the load unit LU can be powered by the DC power supply DCPS. The lithium battery B1 does not need to be discharged, and the second switching unit 102 can be disconnected to reduce the energy consumption of the power supply circuit 1.

[0271] The power supply circuit provided in this application adopts a hybrid topology of MOSFETs and relays, which can achieve the discharge of the energy storage unit ESU through only the first and second switching units, or only the third and fourth switching units. It can be seen that during the discharge process of the energy storage unit ESU, it is not necessary for all four switching units to be closed (or turned on), which can reduce the overall loss and heat generation of the power supply circuit and improve its reliability.

[0272] (4) Protection

[0273] In one possible implementation, when the discharge current of the lithium battery B1 exceeds a preset current threshold, the first switching unit 101 can be directly shut down, thereby protecting the load unit LU and the power supply circuit 1.

[0274] In another possible implementation, when the charging current of lithium battery B1 exceeds a preset current threshold (i.e., lithium battery B1 is overcurrent), since the first switching unit 101 is in the on state and the second switching unit 102 is in the closed state, the power supply circuit 1 can control the fourth switching unit 104 to close, the third switching unit 103 to turn on, the second switching unit 102 to open, and the third switching unit 103 to turn off. This achieves protection for both the power supply circuit 1 and the lithium battery B1.

[0275] Since the second DC voltage output by the energy storage unit ESU (or lithium battery B1) can be equal to the rated voltage of the load unit during the discharge process, the power supply circuit provided in the above embodiments of this application can be called a direct-through circuit. Therefore, a MOSFET with a lower source-drain voltage (i.e., the voltage between the source and drain) and a lower impedance can be selected. Consequently, the current loss of the MOSFET is low, thereby reducing the overall power supply circuit losses.

[0276] Furthermore, the voltage stress required for the two MOSFETs in the power supply circuit provided in this application embodiment is relatively low, making them less prone to damage and ensuring high reliability. Moreover, this application embodiment employs two relays and two MOSFETs. Because the number of switching units (i.e., relays and MOSFETs) used is small, the area of ​​the heat sink for dissipating heat from the entire power supply circuit can be reduced, thereby reducing the cost of the power supply circuit.

[0277] This application also provides an electronic device, such as... Figure 28 As shown, the electronic device H may include an energy storage unit ESU and the aforementioned power supply circuit 1. The power supply circuit 1 may be connected to the energy storage unit ESU and the load unit LU respectively, and the load unit LU may be connected to a DC power supply DCPS.

[0278] The power supply circuit 1 can be used to charge the energy storage unit ESU according to the first DC voltage when the real-time DC voltage of the energy storage unit ESU is lower than or equal to the first DC voltage.

[0279] It is understood that the power supply circuit 1 can also power the load single LU through the main control unit 10 and the auxiliary control unit 20, as can be referred to above, and will not be repeated in the embodiments of this application.

[0280] In one possible implementation, the electronic device 10 can be a battery used to power base stations, data centers, or emergency backup equipment.

[0281] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A power supply circuit, characterized in that, It includes a main control unit and an auxiliary control unit. The main control unit is connected to the energy storage unit and the load unit. The auxiliary control unit is connected to the energy storage unit and the load unit. The energy storage unit is connected to the load unit. The load unit is connected to a DC power supply. The DC power supply is used to: provide a first DC voltage to the load unit, and / or, provide the first DC voltage to the energy storage unit through the power supply circuit; The auxiliary control unit is used to: charge the energy storage unit according to the first DC voltage when the real-time DC voltage of the energy storage unit is lower than the first DC voltage; The main control unit is used to: charge the energy storage unit according to the first DC voltage when the real-time DC voltage of the energy storage unit is equal to the first DC voltage; When the first DC voltage is lower than the rated voltage of the load unit, the auxiliary control unit is used to supply power to the load unit according to the real-time DC voltage of the energy storage unit, and / or the main control unit is used to supply power to the load unit according to the real-time DC voltage of the energy storage unit.

2. The power supply circuit according to claim 1, characterized in that, The power supply circuit also includes a DC-DC converter unit, which is connected to the main control unit, the auxiliary control unit, and the energy storage unit. The DC-DC converter is used to: charge the energy storage unit according to the main control unit and the auxiliary control unit when the real-time DC voltage of the energy storage unit is lower than the first DC voltage; and to reduce the first DC voltage to limit the charging current of the energy storage unit.

3. The power supply circuit according to claim 2, characterized in that, The main control unit includes a first switch unit and a second switch unit, and the auxiliary control unit includes a third switch unit and a fourth switch unit; The first end of the first switching unit is connected to the first end of the energy storage unit, the second end of the first switching unit is connected to the first node, the first ends of the second switching unit and the first ends of the third switching unit are respectively connected to the first node, the second end of the second switching unit is connected to the second node, the second end of the third switching unit is connected to the second end of the fourth switching unit, the first end of the fourth switching unit is connected to the second node, the second node and the first end of the DC power supply are respectively connected to the first end of the load unit, and the second end of the energy storage unit and the second end of the DC power supply are respectively connected to the second end of the load unit.

4. The power supply circuit according to claim 3, characterized in that, The first end of the DC-DC converter is connected to the node between the third switch unit and the fourth switch unit, the second end of the DC-DC converter is connected to the first node or the node between the first switch unit and the energy storage unit, and the third end of the DC-DC converter is connected to the second end of the energy storage unit and the second end of the load unit.

5. The power supply circuit according to claim 2, characterized in that, The main control unit includes a first switch unit and a second switch unit, and the auxiliary control unit includes a third switch unit and a fourth switch unit; The first end of the first switching unit is connected to the second end of the energy storage unit. The second end of the first switching unit and the second end of the DC power supply are respectively connected to the second end of the load unit. The first end of the energy storage unit, the first end of the second switching unit, and the first end of the third switching unit are respectively connected to the first node. The second end of the second switching unit is connected to the second node. The second end of the third switching unit is connected to the second end of the fourth switching unit. The first end of the fourth switching unit is connected to the second node. The second node and the first end of the DC power supply are respectively connected to the first end of the load unit.

6. The power supply circuit according to claim 5, characterized in that, The first end of the DC-DC converter is connected to the node between the third switch unit and the fourth switch unit, the second end of the DC-DC converter is connected to the first node, and the third end of the DC-DC converter is connected to the second end of the first switch unit and the second end of the load unit.

7. The power supply circuit according to claim 5, characterized in that, The first end of the DC-DC converter is connected to the node between the third switch unit and the fourth switch unit, the second end of the DC-DC converter is connected to the first node, and the third end of the DC-DC converter is connected to the first end of the first switch unit and the second end of the energy storage unit.

8. The power supply circuit according to any one of claims 3 to 7, characterized in that, The power supply circuit for charging the energy storage unit includes: when the first switch unit is turned on and the real-time DC voltage of the energy storage unit is lower than the first DC voltage, the power supply circuit controls the fourth switch unit to close and the third switch unit to turn on, and provides the first DC voltage to the energy storage unit through the fourth switch unit, the third switch unit and the first switch unit.

9. The power supply circuit according to any one of claims 3 to 8, characterized in that, The auxiliary control unit is further configured to: supply power to the load unit according to the real-time DC voltage of the energy storage unit when the first DC voltage is lower than the rated voltage of the load unit; or, charge the energy storage unit according to the first DC voltage when the real-time DC voltage of the energy storage unit is equal to the first DC voltage. The main control unit is further configured to: supply power to the load unit according to the real-time DC voltage of the energy storage unit when the first DC voltage is lower than the rated voltage of the load unit.

10. The power supply circuit according to claim 9, characterized in that, The power supply circuit for charging the energy storage unit includes: when the first switching unit is turned on and the real-time DC voltage of the energy storage unit is equal to the first DC voltage, the power supply circuit controls the fourth switching unit to be turned off, the third switching unit to be turned off and the second switching unit to be turned on, and provides the first DC voltage to the energy storage unit through the second switching unit and the first switching unit; The power supply circuit for supplying power to the load unit includes: when the first DC voltage is lower than the rated voltage of the load unit, the power supply circuit controls the third switch unit to turn off, the fourth switch unit to open, the second switch unit to close, and the first switch unit to turn on, and supplies the real-time DC voltage of the energy storage unit to the load unit through the first switch unit and the second switch unit.

11. The power supply circuit according to claim 9 or 10, characterized in that, The power supply circuit for charging the energy storage unit includes: when the real-time DC voltage of the energy storage unit is lower than the first DC voltage, the power supply circuit controls the DC-DC converter to open, the fourth switch unit to close and the first switch unit to turn on, and provides the first DC voltage to the energy storage unit through the fourth switch unit, the DC-DC converter and the first switch unit.

12. The power supply circuit according to claim 9, characterized in that, The power supply circuit for charging the energy storage unit includes: when the first switch unit is turned on and the real-time DC voltage of the energy storage unit is equal to the first DC voltage, the power supply circuit controls the second switch unit to be turned off, the fourth switch unit to be turned on and the third switch unit to be turned on, and provides the first DC voltage to the energy storage unit through the fourth switch unit, the third switch unit and the first switch unit; The power supply circuit for supplying power to the load unit includes: when the first DC voltage is lower than the rated voltage of the load unit, the power supply circuit controls the second switch unit to turn off, the fourth switch unit to close, the third switch unit to turn on, and the first switch unit to turn on, and supplies the real-time DC voltage of the energy storage unit to the load unit through the first switch unit, the third switch unit, and the fourth switch unit.

13. The power supply circuit according to claim 9 or 12, characterized in that, The power supply circuit for charging the energy storage unit includes: when the real-time DC voltage of the energy storage unit is lower than the first DC voltage, the power supply circuit controls the DC-DC converter to open, the fourth switch unit to close and the first switch unit to turn on, and transmits the first DC voltage to the energy storage unit through the fourth switch unit, the DC-DC converter and the first switch unit.

14. The power supply circuit according to claim 9, characterized in that, The power supply circuit for charging the energy storage unit includes: when the first switch unit is turned on and the real-time DC voltage of the energy storage unit is equal to the first DC voltage, the power supply circuit controls the fourth switch unit to close, the third switch unit to turn on and the second switch unit to close, and provides the first DC voltage to the energy storage unit through the second switch unit and the first switch unit, and also provides the first DC voltage to the energy storage unit through the fourth switch unit, the third switch unit and the first switch unit; The power supply circuit for supplying power to the load unit includes: when the first DC voltage is lower than the rated voltage of the load unit, the power supply circuit controls the fourth switch unit to close, the third switch unit to turn on, the second switch unit to close and the first switch unit to turn on, and transmits the real-time DC voltage of the energy storage unit to the load unit through the first switch unit and the second switch unit, and also provides the real-time DC voltage of the energy storage unit to the load unit through the first switch unit, the third switch unit and the fourth switch unit.

15. The power supply circuit according to claim 9 or 14, characterized in that, The power supply circuit for charging the energy storage unit includes: when the real-time DC voltage of the energy storage unit is lower than the first DC voltage provided by the DC power supply, the power supply circuit controls the DC conversion unit to open, the fourth switch unit to close and the first switch unit to turn on, and provides the first DC voltage to the energy storage unit through the fourth switch unit, the DC conversion unit and the first switch unit.

16. The power supply circuit according to any one of claims 3 to 15, characterized in that, The first switching unit and the third switching unit each include one power switch or multiple power switches connected in parallel.

17. The power supply circuit according to claim 16, characterized in that, The power switch is an insulated-gate field-effect transistor or an insulated-gate bipolar transistor.

18. The power supply circuit according to any one of claims 3 to 17, characterized in that, The second switching unit and the fourth switching unit are both mechanical switches; The mechanical switch is any one of a relay, contactor, and circuit breaker.

19. An electronic device, characterized in that, It includes an energy storage unit and a power supply circuit as described in any one of claims 1 to 18, wherein the power supply circuit is connected to the energy storage unit and the load unit respectively, and the load unit is connected to a DC power supply; The power supply circuit is used to charge the energy storage unit according to the first DC voltage when the real-time DC voltage of the energy storage unit is lower than or equal to the first DC voltage.

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