A UPS control system and method with neutral line

Abstract

The present invention relates to a UPS control system and method with a neutral line, including a BMS management system, an energy storage unit, a detection unit and a UPS system; the energy storage unit includes: a positive battery group and a negative battery group; the detection unit collects the discharge current of the positive battery group and the discharge current of the negative battery group during the discharge process of the energy storage unit; the BMS management system calculates the discharge information of the positive battery group and the negative battery group according to the discharge current of the positive battery group and the discharge current of the negative battery group, and outputs a charging request to the UPS system based on the discharge information after the discharge of the energy storage unit is completed; the UPS system charges the positive battery group and the negative battery group according to the charging request. The present invention determines the charging information of the discharge information of the positive and negative battery groups through the BMS management system, so that the UPS system can charge the positive and negative battery groups respectively according to the determined charging information, ensure the consistency of the capacity of the positive and negative battery groups, avoid undercharging or overcharging, and improve the reliability, stability and safety of the battery group.

Description

Technical Field

[0001] The present invention relates to the field of energy storage technology, and more particularly to a UPS control system and method with a neutral line. Background Art

[0002] In a UPS energy storage system with a neutral line, the half-wave load or line internal resistance is inconsistent, resulting in inconsistent capacities of the positive battery pack and the negative battery pack, which in turn leads to insufficient charging of the battery pack (i.e., not fully charged) or overcharging of the battery pack, reducing the reliability and stability of the battery pack. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a UPS control system and method with a neutral line in view of the defects of the prior art.

[0004] The technical solution adopted by the present invention to solve the technical problem is: constructing a UPS control system with a neutral line, including: a BMS management system, an energy storage unit, a detection unit and a UPS system; the energy storage unit includes: a positive battery group and a negative battery group;

[0005] The BMS management system is respectively connected to the energy storage unit, the detection unit and the UPS system, the detection unit is respectively connected to the positive battery pack and the negative battery pack, and the UPS system is respectively connected to the detection unit and the load;

[0006] The detection unit is used to collect the discharge current of the positive battery group and the discharge current of the negative battery group during the discharge process of the energy storage unit;

[0007] The BMS management system is used to detect the discharge current of the positive battery group and the discharge current of the negative battery group collected by the detection unit during the discharge process of the energy storage unit, and perform calculations based on the discharge current of the positive battery group and the discharge current of the negative battery group to obtain the discharge information of the positive battery group and the negative battery group; the BMS management system is also used to output a charging request to the UPS system based on the discharge information of the positive battery group and the negative battery group after the discharge of the energy storage unit is completed;

[0008] The UPS system charges the positive battery group and the negative battery group according to the charging request.

[0009] The UPS control system with a neutral line of the present invention further includes: a switch control module;

[0010] The switch control module is connected to the UPS system, the detection unit and the BMS management system respectively; the switch control module is used to switch on or off according to the control of the BMS management system to control the connection and disconnection between the UPS system and the energy storage unit.

[0011] In the UPS control system with a neutral line of the present invention, it also includes: a charge and discharge control module disposed between the switch control module and the detection unit and connected to the BMS management system;

[0012] The charge and discharge control module is used to perform charge and discharge control according to the control of the BMS management system.

[0013] In the UPS control system with neutral line of the present invention, the detection unit comprises: a first shunt and a second shunt;

[0014] The first shunt is connected to the positive battery pack and the BMS management system respectively, and the second shunt is connected to the negative battery pack and the BMS management system respectively;

[0015] The first shunt is used to collect the discharge current of the positive battery group during the discharge process of the positive battery group; the second shunt is used to collect the discharge current of the negative battery group during the discharge process of the negative battery group.

[0016] In the UPS control system with a neutral line described in the present invention, the charge and discharge control module includes: a first charge and discharge circuit and a second charge and discharge circuit;

[0017] The first charge and discharge circuit is respectively connected to the first shunt, the BMS management system and the switch control module, and the second charge and discharge circuit is respectively connected to the second shunt, the BMS management system and the switch control module;

[0018] The first charge and discharge circuit is used to complete the charge and discharge control of the positive battery pack according to the control of the BMS management system;

[0019] The second charge and discharge circuit is used to complete the charge and discharge control of the negative battery pack according to the control of the BMS management system.

[0020] In the UPS control system with a neutral line of the present invention, the first charge and discharge circuit includes: a first charge switch, a first discharge switch and a pre-charge circuit; the second charge and discharge circuit includes: a second charge switch and a second discharge switch;

[0021] A first end of the first charging switch is connected to the first shunt, a second end of the first charging switch is connected to a first end of the first discharging switch, a third end of the first charging switch is connected to the BMS management system, a second end of the first discharging switch is connected to the switch control module, and a third end of the first discharging switch is connected to the BMS management system;

[0022] The first end of the pre-charging circuit is connected to the first end of the first charging switch, and the second end of the pre-charging circuit is connected to the second end of the first discharging switch;

[0023] The first end of the second charging switch is connected to the second end of the second discharging switch, the second end of the second charging switch is connected to the switch control module, the third end of the second charging switch is connected to the BMS management system, the first end of the second discharging switch is connected to the second shunt, and the third end of the second discharging switch is connected to the BMS management system.

[0024] In the UPS control system with neutral line of the present invention, it also includes: a protection circuit arranged between the detection unit and the charge and discharge control module;

[0025] The protection circuit is used to perform fuse protection when the negative battery pack or the positive battery pack generates a large current.

[0026] In the UPS control system with a neutral line of the present invention, the protection circuit comprises: a first fuse and a second fuse;

[0027] A first end of the first fuse is connected to the first shunt, and a second end of the first fuse is connected to a first end of the first charging switch;

[0028] A first end of the second fuse is connected to the second shunt, and a second end of the second fuse is connected to a first end of the second discharge switch;

[0029] The first fuse is used to perform fuse protection when the positive battery pack generates a large current, and the second fuse is used to perform fuse protection when the negative battery pack generates a large current.

[0030] The present invention also provides a UPS control method with a neutral line, comprising the following steps:

[0031] The BMS management system outputs a conduction control signal to the switch control module;

[0032] The switch control module is turned on according to the conduction control signal to connect the UPS system with the energy storage unit;

[0033] The BMS management system outputs a discharge control signal to a charge and discharge control module;

[0034] The charge and discharge control module performs a discharge operation according to the discharge control signal to discharge the positive battery group and the negative battery group in the energy storage unit;

[0035] During the discharge process of the positive battery pack and the negative battery pack, the detection unit collects the discharge current of the positive battery pack and the discharge current of the negative battery pack and sends them to the BMS management system;

[0036] The BMS management system calculates discharge information of the positive battery group and the negative battery group according to the discharge battery of the positive battery group and the discharge current of the negative battery group, and outputs a charging request to the UPS system according to the discharge information;

[0037] The UPS system charges the positive battery group and the negative battery group according to the charging request.

[0038] In the UPS control method with a neutral line of the present invention, after the UPS system charges the positive battery group and the negative battery group according to the charging request, the method further comprises:

[0039] The detection unit collects the charging current of the positive battery pack and the charging current of the negative battery pack and sends them to the BMS management system;

[0040] The BMS management system monitors a charging state of the positive battery group and a charging state of the negative battery group according to a charging current of the positive battery group and a charging current of the negative battery group.

[0041] The UPS control system and method with a neutral line implemented in the present invention have the following beneficial effects: including a BMS management system, an energy storage unit, a detection unit and a UPS system; the energy storage unit includes: a positive battery group and a negative battery group; the detection unit collects the discharge current of the positive battery group and the discharge current of the negative battery group during the discharge process of the energy storage unit; the BMS management system calculates the discharge information of the positive battery group and the negative battery group according to the discharge current of the positive battery group and the discharge current of the negative battery group, and outputs a charging request to the UPS system based on the discharge information after the discharge of the energy storage unit is completed; the UPS system charges the positive battery group and the negative battery group according to the charging request. The present invention determines the charging information of the discharge information of the positive and negative battery groups through the BMS management system, so that the UPS system can charge the positive and negative battery groups accordingly according to the determined charging information, ensure the consistency of the capacity of the positive and negative battery groups, avoid undercharging or overcharging, and improve the reliability, stability and safety of the battery group. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0043] Figure 1 It is a structural schematic diagram of a first embodiment of a UPS control system with a neutral line provided by the present invention;

[0044] Figure 2 It is a structural schematic diagram of a second embodiment of a UPS control system with a neutral line provided by the present invention;

[0045] Figure 3 It is a flow chart of a UPS control method with a neutral line provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0046] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0047] refer to Figure 1 , which is a structural diagram of Example 1 of a UPS control system with a neutral line provided by the present invention.

[0048] like Figure 1 As shown, the UPS control system with a neutral line includes: a BMS management system 10, an energy storage unit 20, a detection unit 30 and a UPS system 60. The energy storage unit 20 includes: a positive battery group 201 and a negative battery group 202.

[0049] The BMS management system 10 is connected to the energy storage unit 20 , the detection unit 30 and the UPS system 60 , respectively. The detection unit 30 is connected to the positive battery group 201 and the negative battery group 202 , respectively. The UPS system 60 is connected to the detection unit 30 and the load, respectively.

[0050] The detection unit 30 is used to collect the discharge current of the positive battery group 201 and the discharge current of the negative battery group 202 during the discharge process of the energy storage unit 20 .

[0051] The BMS management system 10 is used to detect the discharge current of the positive battery group 201 and the discharge current of the negative battery group 202 collected by the detection unit 30 during the discharge process of the energy storage unit 20, and to perform calculations based on the discharge current of the positive battery group 201 and the discharge current of the negative battery group 202 to obtain the discharge information of the positive battery group 201 and the negative battery group 202; the BMS management system 10 is also used to output a charging request to the UPS system 60 based on the discharge information of the positive battery group 201 and the negative battery group 202 after the discharge of the energy storage unit 20 is completed.

[0052] Optionally, in the embodiment of the present invention, the discharge information of the positive battery group 201 and the negative battery group 202 includes: the discharged capacity of the positive battery group 201 , the discharged capacity of the negative battery group 202 , and the difference in discharge capacity between the positive battery group 201 and the negative battery group 202 .

[0053] Optionally, in the embodiment of the present invention, the charging request carries: the charging current or charging time of the positive battery pack 201 , and the charging current or charging time of the negative battery pack 202 .

[0054] Specifically, in the embodiment of the present invention, during the discharge process of the positive battery group 201 and the negative battery group 202, the detection unit 30 collects the discharge current of the positive battery group 201 and the discharge current of the negative battery group 202, and sends the adopted discharge current of the positive battery group 201 and the discharge current of the negative battery group 202 to the BMS management system 10. After the discharge is completed, the BMS management system 10 calculates based on the discharge current of the positive battery group 201 and the discharge current of the negative battery group 202 to obtain the discharged capacity of the positive battery group 201, the discharged capacity of the negative battery group 202, and the difference in discharge capacity between the positive battery group 201 and the negative battery group 202. At the same time, after calculating the discharged capacity of the positive battery group 201, the discharged capacity of the negative battery group 202, and the difference in discharge capacity between the positive battery group 201 and the negative battery group 202, the BMS management system 10 calculates the charging current or charging time of the positive battery group 201, and the charging current or charging time of the negative battery group 202, respectively, and then forms a charging request with the calculated charging current or charging time of the positive battery group 201, and the calculated charging current or charging time of the negative battery group 202 and sends it to the UPS system 60.

[0055] The UPS system 60 charges the positive battery group 201 and the negative battery group 202 according to the charging request. It can be understood that by determining the charging current or charging time of the positive battery group 201 and the charging current or charging time of the negative battery group 202, the UPS system 60 can charge the positive battery group 201 according to the determined charging current or charging time of the positive battery group 201, and charge the negative battery group 202 according to the determined charging current or charging time of the negative battery group 202, ensuring that after charging is completed, the SOC of the positive battery group 201 and the SOC of the negative battery group 202 remain consistent, thereby ensuring that the discharged capacity of the positive battery group 201 is consistent with the discharged capacity of the negative battery group 202 during the next discharge.

[0056] Further, in some embodiments, Figure 1 As shown, the UPS control system with a neutral line further includes: a switch control module 50.

[0057] Among them, the switch control module 50 is connected to the UPS system 60, the detection unit 30 and the BMS management system 10 respectively; the switch control module 50 is used to turn on or off according to the control of the BMS management system 10 to control the connection and disconnection between the UPS system 60 and the energy storage unit 20.

[0058] Optionally, the switch control module 50 may include a contactor, a relay, a linkage switch, etc.

[0059] Further, in some embodiments, Figure 1 As shown, the UPS control system with a neutral line further includes: a charge and discharge control module 40 which is arranged between the switch control module 50 and the detection unit 30 and connected to the BMS management system 10 .

[0060] The charge and discharge control module 40 is used to perform charge and discharge control according to the control of the BMS management system 10 .

[0061] Further, in some embodiments, Figure 1 As shown, the UPS control system with a neutral line further includes: a protection circuit 70 arranged between the detection unit 30 and the charge and discharge control module 40 .

[0062] The protection circuit 70 is used to perform fuse protection when the negative battery pack 202 or the positive battery pack 201 generates a large current.

[0063] refer to Figure 2 , which is a structural diagram of Embodiment 2 of a UPS control system with a neutral line provided by the present invention.

[0064] like Figure 2 As shown, in this embodiment, the detection unit 30 includes: a first diverter 301 and a second diverter 302 .

[0065] The first shunt 301 is connected to the positive battery group 201 and the BMS management system 10 respectively, and the second shunt 302 is connected to the negative battery group 202 and the BMS management system 10 respectively.

[0066] The first shunt 301 is used to collect the discharge current of the positive battery group 201 during the discharge process of the positive battery group 201 ; the second shunt 302 is used to collect the discharge current of the negative battery group 202 during the discharge process of the negative battery group 202 .

[0067] like Figure 2 As shown, in this embodiment, the charge and discharge control module 40 includes: a first charge and discharge circuit 401 and a second charge and discharge circuit 402 .

[0068] The first charge and discharge circuit 401 is respectively connected to the first shunt 301 , the BMS management system 10 and the switch control module 50 , and the second charge and discharge circuit 402 is respectively connected to the second shunt 302 , the BMS management system 10 and the switch control module 50 .

[0069] The first charge and discharge circuit 401 is used to complete the charge and discharge control of the positive battery group 201 according to the control of the BMS management system 10 .

[0070] The second charge and discharge circuit 402 is used to complete the charge and discharge control of the negative battery group 202 according to the control of the BMS management system 10 .

[0071] Optionally, in some embodiments, the first charge and discharge circuit 401 includes: a first charge switch K11, a first discharge switch K12, and a pre-charge circuit; the second charge and discharge circuit 402 includes: a second charge switch K21 and a second discharge switch K22.

[0072] A first end of the first charging switch K11 is connected to the first shunt 301, a second end of the first charging switch K11 is connected to a first end of the first discharging switch K12, a third end of the first charging switch K11 is connected to the BMS management system 10, a second end of the first discharging switch K12 is connected to the switch control module 50, and a third end of the first discharging switch K12 is connected to the BMS management system 10.

[0073] A first end of the pre-charging circuit is connected to a first end of the first charging switch K11 , and a second end of the pre-charging circuit is connected to a second end of the first discharging switch K12 .

[0074] Optionally, in some embodiments, the pre-charging circuit may include: a pre-charging relay K0 and a pre-charging resistor R0, wherein the pre-charging relay K0 and the pre-charging resistor R0 are connected in series.

[0075] A first end of the second charging switch K21 is connected to a second end of the second discharging switch K22, a second end of the second charging switch K21 is connected to the switch control module 50, a third end of the second charging switch K21 is connected to the BMS management system 10, a first end of the second discharging switch K22 is connected to the second shunt 302, and a third end of the second discharging switch K22 is connected to the BMS management system 10.

[0076] Optionally, in the embodiment of the present invention, the first charging switch K11, the second charging switch K21, the first discharging switch K12, and the second discharging switch K22 may all be relays.

[0077] like Figure 2 As shown, in this embodiment, the BMS management system 10 includes: a first communication module 101 , a second communication module 102 , a current detection module 103 and a DO control module 104 .

[0078] The first communication module 101 is connected to the energy storage unit 20, and is used to complete the communication between the BMS management system 10 and the energy storage unit 20. Optionally, in some embodiments, the first communication module 101 may be a CAN bus.

[0079] The second communication module 102 is connected to the UPS system 60, and is used to complete the communication between the BMS management system 10 and the UPS system 60. Optionally, in some embodiments, the second communication module 102 may use RS485 communication.

[0080] The current detection module 103 is connected to the first shunt 301 and the second shunt 302 respectively, and is used to receive the charging current or discharging current collected by the first shunt 301 , and receive the charging current or discharging current collected by the second shunt 302 .

[0081] The DO control module 104 includes a plurality of DO control ports respectively connected to the first charging switch K11, the first discharging switch K12, the second charging switch K21 and the second discharging switch K22 to complete the on or off control of the first charging switch K11, the first discharging switch K12, the second charging switch K21 and the second discharging switch K22.

[0082] like Figure 2 As shown, after the BMS management system 10 calculates the charging current or charging time of the positive battery group 201 and the charging current or charging time of the negative battery group 202, the UPS management system charges the positive battery group 201 and the negative battery group 202 respectively according to the charging current or charging time of the positive battery group 201 and the charging current or charging time of the negative battery group 202 sent by the BMS management system 10. In the charging process, the first shunt 301 and the second shunt 302 respectively collect the charging current of the positive battery group 201 and the charging current of the negative battery group 202 in real time and send them to the BMS management system 10. The BMS management system 10 controls the switching sequence of the first charging and discharging circuit 401 and the second charging and discharging circuit 402, so that the UPS system 60 can charge the positive battery group 201 and the negative battery group 202 respectively, ensuring that the capacities of the positive battery group 201 and the negative battery group 202 remain consistent.

[0083] For example, if it is monitored that the discharge capacity of the positive battery group 201 is 80% and the discharge capacity of the negative battery group 202 is 50%, then the difference in discharge capacity between the positive battery group 201 and the negative battery group 202 is 30%. At this time, the BMS calculates that the charging current of the positive battery group 201 is 0.7A and the charging time of the negative battery group 202 is 0.5A. At the same time, the BMS management system 10 controls the first charge and discharge circuit 401 to start first and the second charge and discharge circuit 402 to start later, so that the UPS system 60 can charge the positive battery group 201 (0.7A) and the negative battery group 202 (0.5A) respectively according to the charging current provided by the BMS management system 10, thereby ensuring that the capacities of the positive battery group 201 and the negative battery group 202 remain consistent.

[0084] Optionally, the time difference between the first charge and discharge circuit 401 and the second charge and discharge circuit 402 being started successively can be calculated based on the discharged capacity of the positive battery group 201 and the discharged capacity of the negative battery group 202 .

[0085] Furthermore, if Figure 2 As shown, in this embodiment, the protection circuit 70 includes: a first fuse F1 and a second fuse F2.

[0086] A first end of the first fuse F1 is connected to the first shunt 301 , and a second end of the first fuse F1 is connected to a first end of the first charging switch K11 .

[0087] A first end of the second fuse F2 is connected to the second shunt 302 , and a second end of the second fuse F2 is connected to a first end of the second discharge switch K22 .

[0088] The first fuse F1 is used to perform fuse protection when the positive battery pack 201 generates a large current, and the second fuse F2 is used to perform fuse protection when the negative battery pack 202 generates a large current.

[0089] Optionally, in the embodiment of the present invention, the specific value of the large current may be determined by the performance parameters of the battery pack itself.

[0090] Furthermore, if Figure 2 As shown, in this embodiment, the first charge and discharge circuit 401 further includes: a first diode D1 and a second diode D2. The second charge and discharge circuit 402 further includes: a third diode D3 and a fourth diode D4.

[0091] The anode of the first diode D1 is connected to the first end of the first charging switch K11, and the cathode of the first diode D1 is connected to the second end of the first charging switch K11. The anode of the second diode D2 is connected to the second end of the first discharging switch K12, and the cathode of the second diode D2 is connected to the first end of the first discharging switch K12.

[0092] The anode of the third diode D3 is connected to the first end of the second discharge switch K22, and the cathode of the third diode D3 is connected to the second end of the second discharge switch K22. The anode of the fourth diode D4 is connected to the second end of the second charge switch K21, and the cathode of the fourth diode D4 is connected to the first end of the second charge switch K21.

[0093] In the embodiment of the present invention, by connecting a diode in parallel to the charge and discharge switch, it can be ensured that after the mains power is disconnected, a seamless switch can be made to the battery pack, and the battery pack supplies power to the load, thereby avoiding abnormal power supply to the load when the mains power is disconnected.

[0094] It should be noted that in the embodiment of the present invention, if any battery pack triggers protection during the discharge process, the BMS management system controls the corresponding discharge switch to be disconnected. After the discharge switch is disconnected, the entire system cannot work.

[0095] refer to Figure 3 , is a flow chart of an optional embodiment of a UPS control method with a neutral line provided by the present invention. The UPS control method with a neutral line can be implemented by a UPS control system with a neutral line disclosed in an embodiment of the present invention.

[0096] Specifically, Figure 3 As shown, the UPS control method with a neutral line includes the following steps:

[0097] Step S301 : The BMS management system 10 outputs a conduction control signal to the switch control module 50 .

[0098] Step S302 : The switch control module 50 is turned on according to the on control signal, so that the UPS system 60 is connected to the energy storage unit 20 .

[0099] Step S303 : The BMS management system 10 outputs a discharge control signal to the charge and discharge control module 40 .

[0100] Step S304 : the charge and discharge control module 40 performs a discharge operation according to the discharge control signal, so as to discharge the positive battery group 201 and the negative battery group 202 in the energy storage unit 20 .

[0101] Step S305 , during the discharge process of the positive battery group 201 and the negative battery group 202 , the detection unit 30 collects the discharge current of the discharge battery of the positive battery group 201 and the discharge current of the negative battery group 202 and sends them to the BMS management system 10 .

[0102] Step S306, the BMS management system 10 calculates the discharge information of the positive battery group 201 and the negative battery group 202 according to the discharge current of the discharge battery of the positive battery group 201 and the negative battery group 202, and outputs a charging request to the UPS system 60 according to the discharge information. It can be understood that the BMS management system 10 calculates the discharge information of the positive battery group 201 and the negative battery group 202 after the discharge of the positive battery group 201 and the negative battery group 202 is completed.

[0103] Step S307 : The UPS system 60 charges the positive battery group 201 and the negative battery group 202 according to the charging request.

[0104] Furthermore, in some embodiments, after the UPS system 60 charges the positive battery group 201 and the negative battery group 202 according to the charging request, the detection unit 30 collects the charging current of the positive battery group 201 and the charging current of the negative battery group 202 and sends them to the BMS management system 10; the BMS management system 10 monitors the charging status of the positive battery group 201 and the charging status of the negative battery group 202 according to the charging current of the positive battery group 201 and the charging current of the negative battery group 202.

[0105] By monitoring the charging status of the positive battery group 201 and the negative battery group 202 in real time during the charging process, it is possible to determine whether the positive battery group 201 and the negative battery group 202 have been fully charged, whether the charging status is normal, etc., thereby achieving real-time status monitoring of the positive battery group 201 and the negative battery group 202.

[0106] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0107] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may 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 the present invention.

[0108] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0109] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot limit the scope of protection of the present invention. All equivalent changes and modifications made to the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A UPS control system with a neutral line, characterized in that: include: BMS management system, energy storage unit, detection unit and UPS system; The energy storage unit includes: a positive battery pack and a negative battery pack; and also includes: a charge and discharge control module disposed between the switch control module and the detection unit and connected to the BMS management system; The BMS management system is respectively connected to the energy storage unit, the detection unit and the UPS system, the detection unit is respectively connected to the positive battery pack and the negative battery pack, and the UPS system is respectively connected to the detection unit and the load; The detection unit is used to collect the discharge current of the positive battery group and the discharge current of the negative battery group during the discharge process of the energy storage unit; The charge and discharge control module is used to perform charge and discharge control according to the control of the BMS management system; The BMS management system is used to detect the discharge current of the positive battery group and the discharge current of the negative battery group collected by the detection unit during the discharge process of the energy storage unit, and perform calculations based on the discharge current of the positive battery group and the discharge current of the negative battery group to obtain the discharge information of the positive battery group and the negative battery group; the BMS management system is also used to output a charging request to the UPS system based on the discharge information of the positive battery group and the negative battery group after the discharge of the energy storage unit is completed; the BMS management system is specifically used to: after the discharge is completed, perform calculations based on the discharge current of the positive battery group and the discharge current of the negative battery group to obtain the discharged capacity of the positive battery group, the discharged capacity of the negative battery group, and the difference in the discharge capacity between the positive battery group and the negative battery group, and respectively calculate the charging current or charging time of the positive battery group and the charging current or charging time of the negative battery group according to the discharged capacity of the positive battery group, the discharged capacity of the negative battery group, and the difference in the discharge capacity between the positive battery group and the negative battery group, and form the charging request based on the charging current or charging time of the positive battery group and the charging current or charging time of the negative battery group; The UPS system charges the positive battery group and the negative battery group according to the charging request.

2. The UPS control system with a neutral line according to claim 1, characterized in that: Also includes: Switch control module; The switch control module is connected to the UPS system, the detection unit and the BMS management system respectively; the switch control module is used to switch on or off according to the control of the BMS management system to control the connection and disconnection between the UPS system and the energy storage unit.

3. The UPS control system with a neutral line according to claim 1 or 2, characterized in that: The detection unit comprises: a first flow divider and a second flow divider; The first shunt is connected to the positive battery pack and the BMS management system respectively, and the second shunt is connected to the negative battery pack and the BMS management system respectively; The first shunt is used to collect the discharge current of the positive battery group during the discharge process of the positive battery group; the second shunt is used to collect the discharge current of the negative battery group during the discharge process of the negative battery group.

4. The UPS control system with a neutral line according to claim 3, characterized in that: The charge and discharge control module includes: a first charge and discharge circuit and a second charge and discharge circuit; The first charge and discharge circuit is respectively connected to the first shunt, the BMS management system and the switch control module, and the second charge and discharge circuit is respectively connected to the second shunt, the BMS management system and the switch control module; The first charge and discharge circuit is used to complete the charge and discharge control of the positive battery pack according to the control of the BMS management system; The second charge and discharge circuit is used to complete the charge and discharge control of the negative battery pack according to the control of the BMS management system.

5. The UPS control system with a neutral line according to claim 4, characterized in that: The first charge and discharge circuit includes: a first charge switch, a first discharge switch and a pre-charge circuit; the second charge and discharge circuit includes: a second charge switch and a second discharge switch; A first end of the first charging switch is connected to the first shunt, a second end of the first charging switch is connected to a first end of the first discharging switch, a third end of the first charging switch is connected to the BMS management system, a second end of the first discharging switch is connected to the switch control module, and a third end of the first discharging switch is connected to the BMS management system; The first end of the pre-charging circuit is connected to the first end of the first charging switch, and the second end of the pre-charging circuit is connected to the second end of the first discharging switch; The first end of the second charging switch is connected to the second end of the second discharging switch, the second end of the second charging switch is connected to the switch control module, the third end of the second charging switch is connected to the BMS management system, the first end of the second discharging switch is connected to the second shunt, and the third end of the second discharging switch is connected to the BMS management system.

6. The UPS control system with a neutral line according to claim 5, characterized in that: Also includes: A protection circuit provided between the detection unit and the charge and discharge control module; The protection circuit is used to perform fuse protection when the negative battery pack or the positive battery pack generates a large current.

7. The UPS control system with a neutral line according to claim 6, characterized in that: The protection circuit comprises: a first fuse and a second fuse; A first end of the first fuse is connected to the first shunt, and a second end of the first fuse is connected to a first end of the first charging switch; A first end of the second fuse is connected to the second shunt, and a second end of the second fuse is connected to a first end of the second discharge switch; The first fuse is used to perform fuse protection when the positive battery pack generates a large current, and the second fuse is used to perform fuse protection when the negative battery pack generates a large current.

8. A UPS control method with a neutral line, applied to the UPS control system with a neutral line according to any one of claims 1 to 7, characterized in that: The following steps are involved: The BMS management system outputs a conduction control signal to the switch control module; The switch control module is turned on according to the conduction control signal to connect the UPS system with the energy storage unit; The BMS management system outputs a discharge control signal to a charge and discharge control module; The charge and discharge control module performs a discharge operation according to the discharge control signal to discharge the positive battery group and the negative battery group in the energy storage unit; During the discharge process of the positive battery pack and the negative battery pack, the detection unit collects the discharge current of the positive battery pack and the discharge current of the negative battery pack and sends them to the BMS management system; The BMS management system calculates discharge information of the positive battery group and the negative battery group according to the discharge battery of the positive battery group and the discharge current of the negative battery group, and outputs a charging request to the UPS system according to the discharge information; The UPS system charges the positive battery group and the negative battery group according to the charging request.

9. The UPS control method with neutral line according to claim 8, characterized in that: After the UPS system charges the positive battery group and the negative battery group according to the charging request, the UPS system further includes: The detection unit collects the charging current of the positive battery pack and the charging current of the negative battery pack and sends them to the BMS management system; The BMS management system monitors a charging state of the positive battery group and a charging state of the negative battery group according to a charging current of the positive battery group and a charging current of the negative battery group.

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