Control circuit of uninterruptible power supply and uninterruptible power supply

Abstract

The control circuit of the uninterruptible power supply comprises a direct current main switch, a charging and discharging control unit, a battery control switch, a DC / DC converter, a battery management unit and a protection coil. A first contact of the direct-current main switch is connected with a first end of the charging and discharging control unit, a second contact of the direct-current main switch is connected with the battery control switch and the DC / DC converter, a second end of the charging and discharging control unit is connected with the battery control switch, and a third contact of the direct-current main switch is connected with the DC / DC converter and a third end of the charging and discharging control unit. The DC / DC converter is further connected with the battery management unit, and the battery management unit is further connected with the protection coil. Wherein the first contact, the second contact and the third contact are all normally closed contacts. According to the control circuit of the uninterruptible power supply, the situation that the battery is damaged due to the fact that a user forgets to turn off the battery control switch is avoided, and the service life of the uninterruptible power supply is prolonged.

Description

Technical Field

[0001] The present application belongs to the technical field of uninterruptible power supply, and in particular, relates to a control circuit of an uninterruptible power supply and an uninterruptible power supply. Background Art

[0002] An uninterruptible power supply can provide uninterruptible power supply to electronic devices. When the AC power input is normal, the uninterruptible power supply will stabilize the AC power and supply it to the load, while also charging the battery in the uninterruptible power supply. When the AC power is interrupted, the uninterruptible power supply can continue to supply power to the load through inverter conversion of the power of the battery in the uninterruptible power supply.

[0003] Current uninterruptible power supplies usually have a protection function, that is, when the discharge voltage of the uninterruptible power supply is lower than the preset voltage protection threshold, the DC main switch that controls the battery to output power to the load will automatically trip, and then the battery control switch (the switch used to control the battery to supply power to the battery management system) is manually turned off, thereby avoiding battery damage caused by complete discharge of the battery.

[0004] However, in actual applications, users may forget to turn off the battery control switch, which will cause the battery to power the battery management system for a long time, which may cause the battery to be fully discharged and cause damage to the battery, thereby reducing the life of the uninterruptible power supply. Summary of the invention

[0005] In view of this, the embodiments of the present application provide a control circuit of an uninterruptible power supply and an uninterruptible power supply to solve the technical problem of the short life of the existing uninterruptible power supply.

[0006] In a first aspect, an embodiment of the present application provides a control circuit of an uninterruptible power supply, the control circuit comprising a DC main switch, a charge and discharge control unit, a battery control switch, a DC / DC converter, a battery management unit and a protection coil; a first contact of the DC main switch is connected to a first end of the charge and discharge control unit, a second contact of the DC main switch is connected to the battery control switch and the DC / DC converter, a second end of the charge and discharge control unit is connected to the battery control switch, a third contact of the DC main switch is connected to the DC / DC converter and a third end of the charge and discharge control unit, the DC / DC converter is also connected to the battery management unit, and the battery management unit is also connected to the protection coil; wherein the first contact, the second contact and the third contact are all normally closed contacts.

[0007] Optionally, the charge and discharge control unit includes a charging contactor, a discharging contactor, a first diode connected in parallel with the charging contactor, and a second diode connected in parallel with the discharging contactor; the first end of the charging contactor, the first end of the discharging contactor, the cathode of the first diode, and the cathode of the second diode are connected in common.

[0008] Optionally, the charge and discharge control unit also includes a pre-charge resistor, a pre-charge contactor, a third diode and a fourth diode; the first end of the pre-charge resistor, the second end of the discharge contactor, the anode of the second diode and the anode of the third diode are connected together as the first end of the charge and discharge control unit, the second end of the pre-charge resistor is connected to the first end of the pre-charge contactor, and the cathode of the third diode and the cathode of the fourth diode are connected together as the second end of the charge and discharge control unit; the second end of the pre-charge contactor, the second end of the charging contactor, the anode of the first diode and the anode of the fourth diode are connected together as the fourth end of the charge and discharge control unit.

[0009] Optionally, the charge and discharge control unit also includes a fuse and a shunt; the first end of the shunt serves as the third end of the charge and discharge control unit, the second end of the shunt is connected to the first end of the fuse, and the second end of the fuse serves as the fifth end of the charge and discharge control unit.

[0010] Optionally, the control circuit is connected to the battery through the fourth terminal and the fifth terminal of the charge and discharge control unit.

[0011] Optionally, the battery comprises a lithium battery.

[0012] Optionally, the control circuit is connected to the mains power and the anode of the load through the first contact of the DC main switch; the control circuit is connected to the mains power and the cathode of the load through the third contact of the DC main switch.

[0013] Optionally, when the protection coil is in a powered-on state, the first contact, the second contact and the third contact are all in a disconnected state; when the protection coil is in a powered-off state, the first contact, the second contact and the third contact are all in a closed state.

[0014] In a second aspect, an embodiment of the present application provides an uninterruptible power supply, comprising a battery and a control circuit of the uninterruptible power supply as described in any one of the first aspects, wherein the battery is connected to the control circuit.

[0015] Optionally, the battery comprises a lithium battery.

[0016] The control circuit and uninterruptible power supply provided by the embodiments of the present application have the following technical effects:

[0017] The control circuit of the uninterruptible power supply provided in the embodiment of the present application includes a DC main switch, a charge and discharge control unit, a battery control switch, a DC / DC converter, a battery management unit and a protection coil; the first contact of the DC main switch is connected to the first end of the charge and discharge control unit, the second contact of the DC main switch is connected to the battery control switch and the DC / DC converter, the second end of the charge and discharge control unit is connected to the battery control switch, the third contact of the DC main switch is connected to the third end of the DC / DC converter and the charge and discharge control unit, the DC / DC converter is also connected to the battery management unit, and the battery management unit is also connected to the protection coil; wherein the first contact, the second contact and the third contact are all normally closed contacts. Compared with the control circuit of the existing uninterruptible power supply, the control circuit of the uninterruptible power supply of the present application is different in that the battery control switch is connected to a normally closed contact of the DC main switch, and the normally closed contact connected to the battery control switch can be controlled to be disconnected when the DC main switch trips, thereby controlling the transmission link between the battery and the battery management unit to be disconnected, avoiding the situation where the battery is damaged due to the user forgetting to turn off the battery control switch, and improving the life of the uninterruptible power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0019] Figure 1 A schematic diagram of the structure of a control circuit of an uninterruptible power supply provided in an embodiment of the present application;

[0020] Figure 2 A schematic diagram of the structure of a control circuit of an existing uninterruptible power supply provided in an embodiment of the present application;

[0021] Figure 3 A schematic diagram of the structure of a control circuit of an uninterruptible power supply provided by another embodiment of the present application;

[0022] Figure 4 A schematic diagram of the structure of an uninterruptible power supply provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] It should be noted that the terms used in the embodiments of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application. In the description of the embodiments of the present application, unless otherwise specified, "multiple" refers to two or more than two, and "at least one", "one or more" refers to one, two or more. The terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, it is defined that the "first" and "second" features can explicitly or implicitly include one or more of the features.

[0024] References to "one embodiment" or "some embodiments" etc. described in this specification mean that a particular feature, structure or characteristic described in conjunction with the embodiment is included in one or more embodiments of the present application. Thus, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear at different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0025] The present application embodiment first provides a control circuit for an uninterruptible power supply. Figure 1 , Figure 1 A schematic diagram of the structure of a control circuit of an uninterruptible power supply provided in an embodiment of the present application.

[0026] like Figure 1 As shown, the control circuit 10 of the uninterruptible power supply may include a DC main switch 11, a charge and discharge control unit 12, a battery control switch 13, a DC / DC converter 14, a battery management unit 15 and a protection coil 16.

[0027] The control circuit 10 of the uninterruptible power supply can be connected to a battery. In addition, the control circuit 10 of the uninterruptible power supply can also be connected to a mains power supply and a load.

[0028] The first contact of the DC main switch 11 is connected to the first end of the charge and discharge control unit 12 .

[0029] The second contact of the DC main switch 11 is connected to the battery control switch 13 and the DC / DC converter 14 .

[0030] A second end of the charge and discharge control unit 12 is connected to the battery control switch 13 .

[0031] The third contact of the DC main switch 11 is connected to the third end of the DC / DC converter 14 and the charge and discharge control unit 12 .

[0032] The DC / DC converter 14 is further connected to a battery management unit 15 , and the battery management unit 15 is further connected to a protection coil 16 .

[0033] Among them, the first contact, the second contact and the third contact are all normally closed contacts.

[0034] The DC main switch 11 is used to control the on / off of the transmission link between the control circuit 10 of the uninterruptible power supply and the mains power and the load.

[0035] Specifically, the first contact and the third contact in the DC main switch 11 are used to connect to the mains and the load, and the first contact and the third contact in the DC main switch 11 are normally closed contacts.

[0036] When the first contact and the third contact are closed, the transmission link between the control circuit 10 of the uninterruptible power supply and the mains power and the load is connected, and the control circuit 10 of the uninterruptible power supply can obtain the mains power, or the control circuit 10 of the uninterruptible power supply can supply power to the load.

[0037] When the first contact and the third contact are disconnected, the transmission link between the control circuit 10 of the uninterruptible power supply and the mains power and the load is disconnected, and the control circuit 10 of the uninterruptible power supply cannot obtain the mains power, or the control circuit 10 of the uninterruptible power supply cannot supply power to the load.

[0038] The charge and discharge control unit 12 is used to transmit the mains power to the battery, or to transmit the power of the battery to the load.

[0039] The battery control switch 13 is used to control the on / off of the transmission link for the battery to supply power to the battery management unit 15 together with the DC main switch 11 .

[0040] Specifically, when the battery control switch 13 and the second contact in the DC main switch 11 are both closed, the battery can supply power to the battery management unit 15 through the DC / DC converter 14 .

[0041] When the second contact in the battery control switch 13 or the DC main switch 11 is disconnected, the battery may not be able to supply power to the battery management unit 15 through the DC / DC converter 14. In practical applications, the battery control switch 13 is controlled by the user.

[0042] The DC / DC converter 14 is used to receive an input voltage, and perform voltage step-up, voltage stabilization or voltage step-down processing on the input voltage, and finally output a stable voltage.

[0043] The battery management unit 15 is used to control the DC main switch 11. Specifically, the battery management unit 15 can detect the discharge voltage of the control circuit 10 of the uninterruptible power supply. When the discharge voltage of the control circuit 10 of the uninterruptible power supply is lower than the preset protection voltage threshold, the battery management unit 15 can transmit electric energy to the protection coil 16 to make the protection coil 16 in an energized state, thereby controlling the first contact, the second contact, and the third contact in the DC main switch 11 to be disconnected, and then controlling the battery to stop transmitting electric energy to the load and the battery management unit 15.

[0044] The protection coil 16 is used to control the first contact, the second contact and the third contact in the DC main switch 11 .

[0045] Specifically, when the protection coil 16 is in a powered-on state, the protection coil 16 can control the first contact, the second contact, and the third contact in the DC main switch 11 to be disconnected.

[0046] When the protection coil 16 is in a power-off state, the protection coil 16 can control the first contact, the second contact, and the third contact in the DC main switch 11 to close.

[0047] The following is a schematic diagram of the structure of a control circuit of an existing uninterruptible power supply. Figure 2 , Figure 2 A schematic diagram of the structure of a control circuit of an existing uninterruptible power supply provided in an embodiment of the present application.

[0048] The control circuit 10 of the uninterruptible power supply provided in the embodiment of the present application is different from the control circuit of the existing uninterruptible power supply in that the battery control switch is connected to a normally closed contact in the DC main switch, that is, a normally closed contact (second contact) of the DC main switch 11 is added between the battery control switch 13 and the DC / DC converter 14.

[0049] In the existing uninterruptible power supply control circuit, when the battery management system detects that the discharge voltage is lower than the protection voltage threshold, the user needs to manually control the battery control switch to disconnect in order to prevent the battery from discharging to the battery management system for a long time.

[0050] When the battery management unit 15 in the control circuit 10 of the uninterruptible power supply provided in the present application detects that the discharge voltage of the control circuit 10 of the uninterruptible power supply is lower than the protection voltage threshold, it can transmit electric energy to the protection coil 16 to put the protection coil 16 in an energized state, thereby controlling the second contact in the DC main switch 11 to disconnect, and then the path between the battery and the battery management unit 15 can be disconnected. Therefore, there is no need for the user to manually control the battery control switch 13 to disconnect, thereby avoiding the phenomenon that the battery is discharged to the battery management unit 15 for a long time due to the user forgetting to turn off the battery control switch, and finally causing the battery to be damaged.

[0051] As can be seen from the above, the control circuit of the uninterruptible power supply provided in the embodiment of the present application includes a DC main switch, a charge and discharge control unit, a battery control switch, a DC / DC converter, a battery management unit and a protection coil; the first contact of the DC main switch is connected to the first end of the charge and discharge control unit, the second contact of the DC main switch is connected to the battery control switch and the DC / DC converter, the second end of the charge and discharge control unit is connected to the battery control switch, the third contact of the DC main switch is connected to the third end of the DC / DC converter and the charge and discharge control unit, the DC / DC converter is also connected to the battery management unit, and the battery management unit is also connected to the protection coil; wherein the first contact, the second contact and the third contact are all normally closed contacts. Compared with the control circuit of the existing uninterruptible power supply, the control circuit of the uninterruptible power supply of the present application is different in that the battery control switch is connected to a normally closed contact in the DC main switch, and the normally closed contact connected to the battery control switch can be controlled to be disconnected when the DC main switch trips, thereby controlling the transmission link between the battery and the battery management unit to be disconnected, avoiding the situation where the battery is damaged due to the user forgetting to turn off the battery control switch, and improving the life of the uninterruptible power supply.

[0052] See also Figure 3 , Figure 3 A schematic diagram of the structure of a control circuit of an uninterruptible power supply provided in another embodiment of the present application.

[0053] like Figure 3 As shown, in an optional implementation, the charge and discharge control unit 12 may include a charging contactor K1, a discharging contactor K2, a first diode T1, and a second diode T2.

[0054] The charging contactor K1 is connected in parallel with the first diode T1, the discharging contactor K2 is connected in parallel with the second diode T2, and the first end of the charging contactor K1, the first end of the discharging contactor K2, the cathode of the first diode T1 and the cathode of the second diode T2 are connected in common.

[0055] In an optional implementation, the charge and discharge control unit 12 may further include a pre-charge resistor R1 , a pre-charge contactor K3 , a third diode T3 , and a fourth diode T4 .

[0056] The first end of the pre-charging resistor R1 , the second end of the discharge contactor K2 , the anode of the second diode T2 , and the anode of the third diode T3 are connected together as a first end of the charge and discharge control unit 12 .

[0057] The second end of the pre-charging resistor R1 is connected to the first end of the pre-charging contactor K3.

[0058] The cathode of the third diode T3 and the cathode of the fourth diode T4 are connected together to serve as the second end of the charge and discharge control unit 12 .

[0059] The second end of the pre-charging contactor K3 , the second end of the charging contactor K1 , the anode of the first diode T1 , and the anode of the fourth diode T4 are connected together as a fourth end of the charging and discharging control unit 12 .

[0060] In an optional implementation, the charge and discharge control unit 12 may further include a fuse K4 and a shunt K5.

[0061] The first end of the shunt K5 serves as the third end of the charge and discharge control unit 12 .

[0062] The second end of the shunt K5 is connected to the first end of the fuse K4.

[0063] The second end of the fuse K4 serves as the fifth end of the charge and discharge control unit 12 .

[0064] In this implementation, the control circuit of the uninterruptible power supply is connected to the battery via the fourth terminal and the fifth terminal of the charge and discharge control unit 12. In an optional implementation, the battery may include a lithium battery.

[0065] In this implementation, the control circuit of the uninterruptible power supply is connected to the anode of the main power supply and the load through the first contact of the DC main switch 11, and the control circuit of the uninterruptible power supply is connected to the cathode of the main power supply and the load through the third contact of the DC main switch 11.

[0066] The present application also provides an uninterruptible power supply. Figure 4 , Figure 4 A schematic diagram of the structure of an uninterruptible power supply provided in an embodiment of the present application.

[0067] like Figure 4 As shown, the uninterruptible power supply 40 may include an uninterruptible power supply control circuit 10 and a battery, wherein the uninterruptible power supply control circuit 10 is connected to the battery.

[0068] In an optional implementation, the battery may include a lithium-ion battery.

[0069] The following combination Figure 4 , the specific working principle of the uninterruptible power supply provided in the embodiment of the present application is described in detail.

[0070] When the mains power input connected to the uninterruptible power supply 40 is normal, the uninterruptible power supply 40 stabilizes the mains power and supplies it to the load for use, while also charging the battery in the uninterruptible power supply 40. When the mains power connected to the uninterruptible power supply 40 is interrupted, the uninterruptible power supply 40 can continue to supply power to the load by using the power of the battery in the uninterruptible power supply 40 through an inverter conversion method.

[0071] During the process of the uninterruptible power supply 40 supplying electric energy to the load, the battery management unit can detect the discharge voltage of the control circuit of the uninterruptible power supply. When the battery management unit detects that the discharge voltage of the control circuit of the uninterruptible power supply is lower than the protection voltage threshold, the battery management unit can transmit electric energy to the protection coil to put the protection coil in an energized state, thereby controlling the first contact, the second contact and the third contact in the DC main switch to be disconnected.

[0072] Since the first contact and the third contact in the DC main switch are connected between the battery and the load, when the first contact and the third contact in the DC main switch are disconnected, the battery cannot supply power to the load; since the second contact in the DC main switch is connected between the battery and the battery management unit, when the second contact in the DC main switch is disconnected, the battery cannot supply power to the battery management unit, thereby avoiding the situation where the user forgets to turn off the battery control switch, causing the battery to supply power to the battery management system for a long time, and ultimately causing the battery to be fully discharged and damaged.

[0073] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0074] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0075] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A control circuit of an uninterruptible power supply, characterized in that: The control circuit includes a DC main switch, a charge and discharge control unit, a battery control switch, a DC / DC converter, a battery management unit and a protection coil; a first contact of the DC main switch is connected to a first end of the charge and discharge control unit, a second contact of the DC main switch is connected to the battery control switch and the DC / DC converter, a second end of the charge and discharge control unit is connected to the battery control switch, a third contact of the DC main switch is connected to the DC / DC converter and a third end of the charge and discharge control unit, the DC / DC converter is also connected to the battery management unit, and the battery management unit is also connected to the protection coil; wherein the first contact, the second contact and the third contact are all normally closed contacts.

2. The control circuit according to claim 1, characterized in that: The charge and discharge control unit includes a charging contactor, a discharging contactor, a first diode connected in parallel with the charging contactor, and a second diode connected in parallel with the discharging contactor; the first end of the charging contactor, the first end of the discharging contactor, the cathode of the first diode, and the cathode of the second diode are connected in common.

3. The control circuit according to claim 2, characterized in that: The charge and discharge control unit also includes a pre-charge resistor, a pre-charge contactor, a third diode and a fourth diode; the first end of the pre-charge resistor, the second end of the discharge contactor, the anode of the second diode and the anode of the third diode are connected together as the first end of the charge and discharge control unit, the second end of the pre-charge resistor is connected to the first end of the pre-charge contactor, and the cathode of the third diode and the cathode of the fourth diode are connected together as the second end of the charge and discharge control unit; the second end of the pre-charge contactor, the second end of the charging contactor, the anode of the first diode and the anode of the fourth diode are connected together as the fourth end of the charge and discharge control unit.

4. The control circuit according to claim 3, characterized in that: The charge and discharge control unit also includes a fuse and a shunt; the first end of the shunt serves as the third end of the charge and discharge control unit, the second end of the shunt is connected to the first end of the fuse, and the second end of the fuse serves as the fifth end of the charge and discharge control unit.

5. The control circuit according to claim 4, characterized in that: The control circuit is connected to the battery through the fourth terminal and the fifth terminal of the charge and discharge control unit.

6. The control circuit according to claim 5, characterized in that: The battery comprises a lithium battery.

7. The control circuit according to claim 1, characterized in that: The control circuit is connected to the anode of the main power supply and the load through the first contact of the DC main switch; the control circuit is connected to the cathode of the main power supply and the load through the third contact of the DC main switch.

8. The control circuit according to any one of claims 1 to 7, characterized in that: When the protection coil is in a powered-on state, the first contact, the second contact and the third contact are all in an open state; when the protection coil is in a powered-off state, the first contact, the second contact and the third contact are all in a closed state.

9. An uninterruptible power supply, characterized in that: The invention comprises a battery and a control circuit as claimed in any one of claims 1 to 8, wherein the battery is connected to the control circuit.

10. The uninterruptible power supply according to claim 9, characterized in that: The battery comprises a lithium battery.

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