Distributed AC / DC uninterruptible power supply system

Abstract

The invention provides a distributed AC / DC uninterruptible power supply system, which comprises a PLC main control module and a power supply monitoring controller, the AC-DC rectifier module provides a main power supply for the system; the alternating-current and direct-current inverter is used for current conversion and providing an uninterrupted alternating-current power supply; the static switch performs power supply switching between the battery pack and the commercial power; the direct-current starting module activates a direct-current starting function and realizes alternating-current and direct-current uninterruptible power supply; the four-port isolation module realizes current single-phase flow of the battery pack and the intelligent charger; the battery management module is used for uninterruptedly supplying power; the intelligent heat dissipation module is used for automatically dissipating heat in a high-power operation state; and the human-computer interface and the configuration software are used for displaying the operation data and the operation state in real time and carrying out remote management. The battery pack is in an off-line mode; a high-speed switch is adopted for switching, a complete battery management system is adopted, the service life of a battery pack is prolonged, reliable alternating-current and direct-current uninterruptible power supply is achieved, faults are reduced, and intelligent power supply management is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of power supply systems, and in particular to a distributed AC / DC uninterruptible power supply system. Background Art

[0002] Most continuously running digital devices require uninterrupted power supply. The current solutions all use AC UPS technology, which is based on a dual conversion route of converting AC power to DC and DC to AC. This system is complex, has low conversion efficiency, an imperfect battery management system, a short battery life, a high failure rate, a large size, and a high overall cost of use. For DC loads or AC / DC dual-use loads, there are currently power systems (HVDC) based on the use of high-frequency switching power supply module superposition mode to replace traditional UPS. However, HVDC is actually also a dual conversion technology, and the failure rate of the module is still too high. At the same time, it is a system for medium and large power loads, with a large size and high overall cost of use.

[0003] Although the existing uninterruptible power supply has made progress, it still has not gotten rid of the problems of complex system, low reliability and low efficiency. For large data IDC computer rooms, there are many system paralysis caused by UPS power supply problems. Although the existing distributed uninterruptible DC power supply system has made up for the above shortcomings, it still cannot fully meet the needs of existing data computer rooms without an AC output system (most existing data computer rooms still need a small amount of AC power supply). Most of the existing uninterruptible power supplies use battery online, and the battery pack is in a long-term floating charge state and is easily damaged. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a distributed AC / DC uninterruptible power supply system, in which the battery pack is in offline mode; high-speed switch switching and a complete battery management system are used to extend the service life of the battery pack, achieve reliable AC / DC uninterruptible power supply, reduce the occurrence of faults, and realize intelligent power supply management.

[0005] To achieve the above object, the present invention provides the following solution: a distributed AC / DC uninterruptible power supply system, comprising:

[0006] PLC main control module, used for monitoring and controlling power supply;

[0007] The AC / DC rectifier module is used to rectify the output pulsating power supply, provide the main power supply for the system, and accept the control of the PLC main control module;

[0008] AC-DC inverter, used for current conversion, to provide uninterrupted AC power to AC power loads;

[0009] A static switch is used to switch the power supply between the battery pack and the mains through the PLC main control module; the static switch is composed of a static switch control board and a high-speed electronic switch connected in parallel with a high-power relay, and the battery pack is in an offline mode;

[0010] The DC start-up module is used to start the DC output switch with one button when there is no mains power and AC and DC power are needed, activate the DC start-up function, and realize uninterrupted AC and DC power supply;

[0011] A four-port isolation module, used to isolate the main circuit and the smart charger using a four-port high-power diode, so as to achieve single-phase current flow between the battery pack and the smart charger;

[0012] A battery management module, used for providing uninterrupted power supply by using the two battery packs, two BMS main control boards, the smart charger and the battery pack switch; a protection board and a thermostat are provided inside the battery pack, and the BMS main control board is provided with a detection function;

[0013] Intelligent heat dissipation module, used to automatically dissipate heat using multiple AC and DC fans and thermostats under high-power operation;

[0014] Human-machine interface and configuration software are used to display operating data and operating status in real time, and to communicate data through the communication interface to achieve remote management;

[0015] Among them, the PLC main control modules are directly or indirectly connected to the AC / DC rectifier module, the AC / DC inverter, the static switch, the DC starting module, the four-port isolation module, the battery management module, the intelligent heat dissipation module and the human-machine interface and configuration software.

[0016] Optionally, the PLC main control module is directly or indirectly connected to the AC / DC rectifier module, the AC / DC inverter, the static switch, the DC start-up module, the four-port isolation module, the battery management module, the intelligent heat dissipation module, the human-machine interface and the configuration software, including:

[0017] The PLC main control module is connected to the mains, the positive and negative electrodes of the AC / DC rectifier module, the AC / DC inverter, the static switch, the positive electrode of the battery pack, the positive electrode of the input end of the intelligent charger, the intelligent heat dissipation module, the human-machine interface and the configuration software;

[0018] The input end of the AC / DC rectifier module is connected to the mains, and the output end of the AC / DC rectifier module is connected to the DC power load, the AC / DC inverter, the PLC main control module, the static switch, the battery pack, the intelligent charger and the DC power load;

[0019] The AC / DC inverter is connected to the mains, the output end of the AC / DC rectifier module, the AC power load, the PLC main control module, the human-machine interface and the configuration software;

[0020] The static switch is connected to the positive pole of the AC / DC rectifier module, the PLC main control module and the four-port isolation module;

[0021] The DC starting module is connected to the static switch;

[0022] The four-port isolation module is connected to the static switch, the output terminal of the smart charger and the battery pack;

[0023] The battery pack is connected to the BMS main control board, the four-port isolation module and the AC / DC rectifier module, and the BMS main control board is connected to the PLC main control module and the human-machine interface and configuration software;

[0024] The intelligent heat dissipation module is connected to the PLC main control module;

[0025] The human-machine interface and configuration software are connected to the AC / DC inverter, the PLC main control module and the battery management module.

[0026] Optionally, the PLC main control module includes:

[0027] A mains power normal control unit, used for, when the mains power is normal, using the AC / DC inverter and the AC bypass to output AC power, and then using the smart charger and the output AC power to charge the battery pack until the battery pack is fully charged, and charging the battery pack again when the battery pack is discharged to a set value;

[0028] A monitoring unit, used for real-time monitoring of the mains voltage, the battery pack voltage, the charge and discharge current, the charge and discharge voltage, the static switch state, the system power input switch state, the DC output switch state, the AC output switch state, the battery pack switch state and the AC / DC inverter switch state;

[0029] The mains abnormality control unit is used to determine whether the mains is in a high voltage state, a high voltage recovery state, a low voltage state, a low voltage recovery state or a mains disappearance state, and to control the determination result.

[0030] Optionally, the mains power abnormality control unit includes:

[0031] The high voltage subunit is used to determine whether the mains power is greater than 245V / AC. If so, a high voltage sound and light warning is issued through the human-machine interface and the configuration software, the static switch is automatically closed, and then the AC / DC rectifier module and the AC / DC inverter are turned off in sequence to realize the power supply of the battery pack and complete the high voltage control of the mains power;

[0032] The high voltage recovery subunit is used to determine whether the mains power is less than 240V / AC. If so, the AC / DC rectifier module and the AC / DC inverter are turned on first, and then the static switch is automatically disconnected, and finally the smart charger is turned on. The high voltage sound and light warning disappears, the mains power supply is realized, and the high voltage recovery of the mains power is completed;

[0033] The low voltage subunit is used to determine whether the mains power is less than 190V / AC. If so, a low voltage sound and light warning is issued through the human-machine interface and the configuration software, the intelligent charger is turned off, and then the static switch is automatically closed, and finally the AC / DC rectifier module and the AC / DC inverter are turned off in sequence to realize the power supply of the battery pack and complete the low voltage control of the mains power;

[0034] The low voltage recovery subunit is used to determine whether the mains power is greater than 198V / AC. If so, the AC / DC rectifier module and the AC / DC inverter are turned on after a delay of 4.7s, and then the static switch is automatically disconnected. Finally, the smart charger is turned on to perform charging maintenance on the battery pack. The low voltage sound and light warning disappears, and the low voltage recovery of the mains power is completed.

[0035] The mains power disappearance subunit is used to determine whether the mains power disappears. If so, the AC / DC rectifier module, the AC / DC inverter and the smart charger are turned off, the static switch is automatically closed, and the power supply is switched to the battery pack; wherein the switching time is less than 5ms.

[0036] Optionally, the smart charger operates under the control of the PLC main control module, the input voltage of the smart charger is 220V / AC-240V / DC, the output voltage is 0-300V DC continuously adjustable, the output current is 0-4A DC continuously adjustable, and the power is 1200W. The smart charger is internally provided with a smart fan connected to the battery management module. When the battery pack is full, the smart charger automatically shuts down, and when the battery needs to be charged, the smart charger automatically turns on.

[0037] Optionally, the static switch includes:

[0038] An opening unit, used to first close the high-speed electronic switch and then turn on the relay to complete the opening of the static switch;

[0039] The closing unit is used to first close the relay and then disconnect the high-speed electronic switch to complete the closing of the static switch.

[0040] Optionally, the battery management module includes:

[0041] A BMS main control unit, used to monitor the voltage and temperature of the battery management module in real time using the two BMS main control boards. When the monitoring value is greater than a set monitoring threshold, the battery pack switch trips, and the human-machine interface and configuration software issue a tripping sound and light warning, and display that the battery pack switch is in a tripped state. When the monitoring value is less than the monitoring threshold, the battery pack switch is manually restored;

[0042] A battery capacity control unit, used to determine whether the voltage of the battery management module drops to a preset drop threshold when the battery pack is offline, and if so, to start the smart charger by using the PLC main control module to charge the battery pack until it is fully charged for 15 minutes. During the charging process, when the voltage of the battery pack is abnormal, the smart charger stops charging;

[0043] The delayed start unit is used to delay the start of the smart charger for 30 seconds when the mains power is turned on after a power outage.

[0044] Optionally, the intelligent heat dissipation module includes:

[0045] A fan start unit, used to determine whether the temperature of the thermostat in the AC / DC rectifier module, the temperature of the thermostat in the smart charger, the charging current, the DC current output, the AC current output or the discharge current is greater than or equal to the corresponding fan start threshold, and if so, automatically start the AC / DC fan, and record and display the running time and running status of the AC / DC fan through the human-machine interface and configuration software;

[0046] The fan shutoff unit is used to determine whether the temperature of the thermostat in the AC / DC rectifier module, the temperature of the thermostat in the smart charger, the charging current, the DC current output, the AC current output or the discharge current are all less than or equal to the corresponding fan shutoff threshold. If so, the human-machine interface and configuration software record and display the operating time and operating status of the AC / DC fan.

[0047] Optionally, the human-machine interface and configuration software include:

[0048] A display unit is used to display operating data and operating status in real time, and to set the threshold, charging voltage and charging current of the battery management module; the operating data includes real-time display of DC output voltage, DC output current, DC output power, AC output voltage, AC output current, AC output power, AC output frequency, battery pack voltage, battery management module voltage and maximum voltage difference, charging current, charging voltage, AC and DC fan operating time, intelligent charger operating time, battery pack charging and discharging data, battery pack charging and discharging curve, current warning information and historical warning data; the operating status includes power input switch status, DC output switch status, AC output switch status, battery pack switch status, static switch status, AC and DC fan operating status and intelligent charger operating status;

[0049] The configuration software unit is used to communicate data with the BMS main control board, the PLC main control module and the AC / DC inverter by using the communication port, and to send operation data to the outside to realize remote management.

[0050] The present invention discloses the following technical effects by providing a distributed AC / DC uninterruptible power supply system:

[0051] 1. Reliable AC / DC uninterruptible power supply: 1) AC / DC dual power output is realized (DC output adopts a half-air bridge to realize the main circuit uncontrolled rectification and commissioning removal operation, and AC output adopts AC bypass and inversion); 2) The battery pack adopts offline mode and a complete battery management module (automatic maintenance) to detect the operating status of the battery in real time. When an abnormality is found, it automatically maintains or cuts off the battery power supply, ensuring the safe operation of the battery pack and extending the battery life. 3) When the mains power drifts significantly, it automatically switches to battery power supply, and automatically returns to mains power supply when the mains power is restored, ensuring the safe operation of the server in the computer room; 4) In an environment without mains power, a DC one-button start is performed to achieve AC / DC uninterruptible power supply. 5) BMS management is disconnected from the battery main circuit, and the main circuit adopts a combined circuit breaker to avoid damage to the BMS board due to large current. Even if the BMS board fails, the battery still supplies power.

[0052] 2. The present invention adopts a four-port isolation module, which completely isolates the main circuit from the intelligent charger, cuts off the unidirectional connection of the circulation between the battery packs, and protects various components. In particular, it protects the battery pack when a fault occurs. The four-port isolation module is implemented by a single-phase full-wave rectifier bridge. If a backup battery pack needs to be added, a 5-port three-phase bridge can be selected to implement it.

[0053] 3. High-speed switching of battery power supply: quickly capture breakpoints under the state of pulsating current output to achieve high-speed (4MS) switching. Effectively ensure the offline mode of the battery pack. The switching adopts the action arrangement of first closing and then breaking (that is, first turn on the static switch and then turn off the AC / DC rectifier module, first turn on the AC / DC rectifier module and then turn off the static switch). The static switch device adopts the parallel connection of electronic high-speed switch and high-power relay (close the electronic switch first and then turn on the relay when opening, and turn off the relay first and then disconnect the electronic switch when closing), which ensures the reliability of power supply.

[0054] 4. Intelligent charging. The charger is managed by a PLC main control board to avoid the impact of heat generation during charging on data collection and transmission. The charger will be powered off after charging is completed and will automatically start when charging is needed. This minimizes the working time of the charger and improves the stability of the system.

[0055] 5. Intelligent heat dissipation: The fan is started by a thermostat and software control, and the fan is started or shut down according to the load size and the temperature inside the chassis. Use the fan reasonably to ensure system heat dissipation.

[0056] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0058] Figure 1 A schematic diagram of a system architecture provided by an embodiment of the present invention;

[0059] Figure 2 A topological diagram of the system architecture provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0060] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0062] like Figure 1-2 As shown, the present invention provides a distributed AC / DC uninterruptible power supply system. The system DC output uses single-phase mains power to directly supply power to the load after full-wave rectification, which greatly improves the system reliability and efficiency; the system AC output uses AC bypass + DC inverter, and the battery pack is offline for backup, avoiding long-term floating charge of the battery pack and reducing the battery life.

[0063] A distributed AC / DC uninterruptible power supply system comprises:

[0064] 1. PLC master control module

[0065] Used to monitor and control power supply.

[0066] 1.1 Function: Cooperate with the human-machine interface (HMI) and configuration software to monitor and control the AC / DC rectifier module, static switch, intelligent charger, DC / AC inverter, and intelligent heat dissipation to ensure the normal operation of the system; use 240V / 24V voltage transformation to power the HMI and two BMS main control boards.

[0067] 1.2 Connection and function of each port:

[0068] Control and detection connection relationship (such as Figure 2 ) as shown by the green line in the figure: 1) connected to the AC / DC rectifier module to control the switch of the AC / DC rectifier module; 2) connected to the static switch to control the opening or closing of the static switch; 3) connected to the smart charger to control the switch of the smart charger; real-time monitoring of the charger charging and discharging (voltage and current); 4) connected to the DC / AC inverter to control the switch of the DC / AC inverter; 5) connected to the smart heat dissipation to control the start or stop of the smart heat dissipation; 6) connected to the positive poles of the two battery packs to monitor the voltage of the battery packs in real time; 7) connected to the mains to monitor the AC input voltage in real time.

[0069] DC positive and negative connection relationship (such as Figure 2 As shown by the red and black lines in the figure): 1) Connected to the input terminal of the smart charger to power the smart charger; 2) Connected to the AC / DC rectifier module (positive and negative poles) to monitor the DC output voltage in real time; at the same time, it provides working power for the PLC main control and intelligent heat dissipation; 3) Connected to HMI, BAT (1,2) to provide 24V power; 4) Connected to the positive pole of the smart charger input to provide charging power; when the charger needs to be turned off, the power is cut off, and it automatically supplies power when charging is required.

[0070] Communication relationship (such as Figure 2 (as shown by the blue line in the figure): connected to the human-machine interface and configuration software for data communication.

[0071] PLC master control module includes:

[0072] 1.3 Mains normal control unit

[0073] When the mains power is normal, the load directly draws power from the AC / DC rectifier module; the DC / AC inverter is turned on by the power-on signal sent by the PLC main control module, and outputs AC power through the AC bypass; the smart charger charges the battery pack by taking the pulsating voltage after full-wave rectification through the PLC main control module (the static switch disconnects the battery pack from all loads); after the battery is fully charged, the PLC main control module cuts off the power supply to the smart charger (the smart charger is turned off); when the battery pack self-discharges to the set value, the PLC main control module supplies power to the smart charger again (the smart charger is turned on) until the battery pack is fully charged.

[0074] 1.4 Monitoring Unit

[0075] Used for real-time monitoring of the mains voltage, the battery pack voltage, the charge and discharge current, the charge and discharge voltage, the static switch state, the system power input switch state, the DC output switch state, the AC output switch state, the battery pack switch state and the AC / DC inverter switch state.

[0076] 1.5 Mains abnormality control unit

[0077] It is used to judge whether the mains power is in a high voltage state, a high voltage recovery state, a low voltage state, a low voltage recovery state or a mains power disappearance state, and control the judgment result. The mains power abnormality control unit includes:

[0078] 1.51 High Voltage Subunit

[0079] It is used to judge whether the mains power is greater than 245V / AC. If so, a high-voltage sound and light warning (>250V / AC) is issued through the human-machine interface and configuration software, and the static switch is automatically closed, and then the AC / DC rectifier module and the AC / DC inverter are turned off in turn, and the switch is seamless. The battery pack is used to supply power and the high voltage control of the mains power is completed;

[0080] 1.52 High voltage recovery subunit

[0081] Used to determine whether the mains power is less than 240V / AC. If so, first turn on the AC / DC rectifier module and the AC / DC inverter, then automatically disconnect the static switch, and finally turn on the smart charger for seamless switching. The high-voltage sound and light warning disappears, the mains power supply is realized, and the high voltage recovery of the mains power is completed;

[0082] 1.53 Low voltage subunit

[0083] Used to determine whether the mains power is less than 190V / AC. If so, a low-voltage sound and light warning is issued through the human-machine interface and configuration software, the smart charger is turned off, the static switch is automatically closed, and finally the AC / DC rectifier module and the AC / DC inverter are turned off in sequence to realize the power supply of the battery pack and complete the low voltage control of the mains power;

[0084] 1.54 Low voltage recovery subunit

[0085] Used to determine whether the mains power is greater than 198V / AC. If so, the AC / DC rectifier module and the AC / DC inverter are turned on after a delay of 4.7s, and then the static switch is automatically disconnected. Finally, the smart charger is turned on to perform charging maintenance on the battery pack. The low-voltage sound and light warning disappears, and the low-voltage recovery of the mains power is completed;

[0086] 1.55 Mains power failure subunit

[0087] It is used to determine whether the mains power is lost. If so, the AC / DC rectifier module, the AC / DC inverter and the smart charger are turned off, the static switch is automatically closed, and the power supply is switched to the battery pack; wherein the switching time is less than 5ms, and the actual measurement is (2-4ms).

[0088] 1.6 Smart Charger

[0089] The smart charger works under the control of the PLC master, with a universal input voltage of 220V / AC-240V / DC; the output voltage is continuously adjustable from 0-300V DC; the output current is continuously adjustable from 0-4A DC. The output voltage and current are controlled from 0-5V; the power is 1200W. It has a built-in smart fan, which automatically maintains the battery pack with the BMS battery management system. It automatically shuts down when the battery is full and automatically starts up when the battery needs to be charged; it is small in size, high in power and stable in operation.

[0090] For example, this system can be configured with a high-frequency intelligent 1200W charger to perform maintenance charging on the battery pack alone (regardless of the load), charge the battery pack when the mains power is normal (battery offline state), and the charger will automatically shut down when the battery pack voltage reaches the set value; in the battery offline state, when the battery pack voltage is lower than the set value due to self-discharge, the charger will automatically start to recharge the battery pack until it is fully charged, and the charger will automatically shut down. This greatly reduces the use time of the charger and maximizes the service life of the charger. When the mains power is abnormal, the charger will automatically shut down and the battery pack will discharge; when the mains power is restored: the battery pack is offline, the charger will automatically start to charge the battery pack until it is fully charged, and then the charger will shut down again; the system is equipped with a charger cumulative working time statistics to facilitate the work of maintenance personnel.

[0091] 2. AC / DC rectifier module

[0092] It is used to rectify and output pulsating power, provide the main power supply for the system, and accept the control of the PLC main control module.

[0093] 2.1 Function: Full-wave rectifier outputs pulsating power, provides the main power supply for the system, and is controlled by the PLC master to turn on or off the AC / DC rectifier module.

[0094] 2.2 Connection and function of each port:

[0095] Communication connection relationship (such as Figure 2 The input terminal is connected to the mains to provide the main power supply for the system.

[0096] DC connection relationship (such as Figure 2 The output end is connected to the DC load and supplies power; the output end is connected to the DC / AC inverter to provide DC power; the output end is connected to the PLC main control to provide working power, and the charger and intelligent heat dissipation are powered by the PLC main control; the positive pole of the output end is connected to the static switch device, and when the AC / DC rectifier module stops working, the static switch is turned on to provide a power supply channel for the battery pack; the negative pole of the output end is connected to the negative pole of the battery pack, the negative pole of the intelligent charger (input and output), the negative pole of the DC load, the negative pole of the DC / AC inverter DC input, and the negative pole of the PLC main control to provide a DC power supply circuit.

[0097] Controls the detection of connection relationships (such as Figure 2 (as shown by the green line in the figure): connected to the PLC master and controlled by the PLC master.

[0098] 3. AC / DC inverter

[0099] Used for current conversion to provide uninterrupted AC power to AC power loads.

[0100] 3.1 Function: Provide uninterrupted 220V / 50HZ AC power to AC load.

[0101] 3.2 Connection and function of each port:

[0102] DC positive and negative connection relationship (such as Figure 2 (as shown by the red and black lines in the figure): connected to the output end of the AC / DC rectifier module, receiving DC power supply, and providing a power supply channel for the battery pack through the static switch device and the negative electrode of the battery pack (black line) when the AC / DC rectifier module stops working (red line);

[0103] Communication connection relationship (such as Figure 2 (shown by the magenta line in the figure): connected to the mains to provide AC bypass power; connected to the AC load to supply power;

[0104] Controls the detection of connection relationships (such as Figure 2As shown by the green line in the figure): connected to the PLC master and controlled by the PLC master.

[0105] Communication connection relationship (such as Figure 2 (shown by the blue line in the figure): Connect with HMI to realize data transmission.

[0106] 4. Static switch

[0107] Used to switch the power supply between the battery pack and the mains through the PLC main control module; the static switch consists of a static switch control board and a high-speed electronic switch connected in parallel with a high-power relay, and the battery pack is in an offline mode.

[0108] 4.1 Function: High-speed switching is achieved under the control of PLC master control; DC startup control is used to start the machine without AC.

[0109] 4.2 Connection and function of each port:

[0110] DC connection relationship (such as Figure 2 As shown by the red and black lines in the figure: connected to the positive pole of the AC / DC rectifier module and the isolation module. When the AC / DC rectifier module stops working (the static switch is closed), the battery pack supplies power to the system; when the AC power is normal (the static switch is disconnected), the battery pack is disconnected, and the charger is disconnected from the output circuit.

[0111] Controls the detection of connection relationships (such as Figure 2 (as shown by the green line in the figure): connected to the PLC master and receives the switching signal.

[0112] The static switch comprises:

[0113] 4.3 Opening the unit

[0114] It is used to first close the high-speed electronic switch and then turn on the relay to complete the opening of the static switch.

[0115] 4.4 Closing Units

[0116] It is used to first turn off the relay and then disconnect the high-speed electronic switch to complete the turning off of the static switch.

[0117] The switching time is less than 4 milliseconds (national standard 10ms), which is a very reliable action time. For a power supply with a 20ms cycle, 4ms switching can fully meet the requirements of uninterrupted power supply.

[0118] 5. DC starting module

[0119] It has a DC start function. When there is no mains power and AC and DC power are needed, the DC output switch is turned on with one button to achieve one-button start. When the DC output switch is turned on, the one-button start button is invalid to prevent misoperation in the AC power supply state and achieve uninterrupted AC and DC power supply. It is suitable for uninterrupted AC and DC power supply in the field or in mobile situations.

[0120] Connection and function of each port: Connect to the static switch device to control the closing or opening of the static switch.

[0121] 6. Four-port isolation module

[0122] It is used to isolate the main circuit and the intelligent charger by using a 4-port high-power diode, so as to realize the single-phase flow of current of the battery pack and the intelligent charger.

[0123] 6.1 Function: The four-port isolation module is used to completely isolate the main circuit from the charger and the unidirectional path of the battery pack, thus protecting all components.

[0124] 6.2 Connection and function of each port:

[0125] DC connection relationship (such as Figure 2 (as shown by the red and black lines in the figure): connected to the static switch device to provide a one-way path for powering the battery pack; connected to the output end (positive pole) of the smart charger to provide a one-way charging path for the battery pack (1, 2); connected to the battery pack, the one-way conduction isolates the two battery groups from each other and provides a charging path for the battery pack.

[0126] 7. Battery management module

[0127] It is used to use two battery packs, two BMS main control boards, the smart charger and the battery pack switch to provide uninterrupted power supply; the battery pack is provided with a protection board and a thermostat, and the BMS main control board is provided with a detection function

[0128] 7.1BMS main control board

[0129] With battery management function, connected to the battery pack, real-time monitoring (10) voltages, temperatures, battery pack voltage. Get 24V power supply to the PLC master. Connected to HMI for data communication.

[0130] 7.2 Battery Pack

[0131] Composition: 10 (7 series and 7 parallel) 24V lithium battery modules are connected in series to form a 240V / 20AH battery pack, which can be equipped with 2 groups.

[0132] Connected to the isolation module to provide a unidirectional charging and discharging path; connected to the negative pole of the AC / DC rectifier module to provide a battery power supply circuit; connected to the BMS to provide the voltage and temperature of each module (2*10) to the BM.

[0133] The battery management module comprises:

[0134] 7.3BMS main control unit

[0135] It is used to monitor the voltage and temperature of the battery management module in real time using the two BMS main control boards (each module can be monitored, and the battery management module is taken as an example). When the monitoring value is greater than the set monitoring threshold, the battery pack switch trips, and the human-machine interface and configuration software issue a tripping sound and light warning, and display that the battery pack switch is in a tripped state. When the monitoring value is less than the monitoring threshold, the battery pack switch is manually restored.

[0136] 7.4 Battery Capacity Control Unit

[0137] It is used to determine whether the voltage of the battery management module drops to a preset drop threshold when the battery pack is offline. If so, the PLC main control module is used to start the smart charger to charge the battery pack until it is fully charged for 15 minutes (to ensure the full capacity of the battery). During the charging process, when the battery pack voltage is abnormal, the smart charger stops charging.

[0138] 7.5 Delay start unit

[0139] When the battery is discharged after a power outage and power is restored again, the smart charger will delay turning on for 30 seconds to reduce the system impact current.

[0140] 8. Intelligent cooling module

[0141] It is used to automatically dissipate heat in high-power operation by using multiple AC and DC fans (3 80*80*25240V AC and DC fans) and thermostats, in conjunction with the human-machine interface, configuration software and PLC main control module. The intelligent heat dissipation module includes:

[0142] 8.1 Fan start unit

[0143] Used to determine whether the temperature of the thermostat in the AC / DC rectifier module is ≧75℃±5℃, the temperature of the thermostat in the smart charger is ≧45℃±5℃, the charging current is ≧2A, the DC current output is ≧8A, the AC current output is ≧3A or the discharge current is ≧8A, and whether the above are greater than or equal to the corresponding fan start threshold (any one of them can be met). If so, the AC / DC fan is automatically turned on, and the operating time and operating status of the AC / DC fan are recorded and displayed through the human-machine interface and configuration software.

[0144] 8.2 Fan Shutdown Unit

[0145] Used to determine whether the temperature of the thermostat in the AC / DC rectifier module is ≤ (65℃±5℃), the temperature of the thermostat in the smart charger is ≤ (35℃±5℃), the charging current is ≤ 1A, the DC current output is ≤ 5A, the AC current output is ≤ 2A or the discharge current is ≤ 4A, and whether the above are all less than or equal to the corresponding fan shutdown threshold (all items must be met). If so, the human-machine interface and configuration software record and display the operating time and operating status of the AC / DC fan, and the system delays 5 minutes to shut down the fan.

[0146] 9. Human-machine interface and configuration software

[0147] It is used to display the operation data and operation status in real time, and to communicate data through the communication interface to achieve remote management. The human-machine interface and configuration software include:

[0148] 9.1 Display Unit

[0149] Used to display operating data and operating status in real time, and set the threshold, charging voltage and charging current of the battery management module; the operating data includes real-time display of DC output voltage, DC output current, DC output power, AC output voltage, AC output current, AC output power, AC output frequency, battery pack voltage, battery management module voltage (including the voltages of all modules, taking the battery management module as an example here) and the maximum voltage difference (i.e. the maximum difference between the voltages of all modules), charging current, charging voltage, AC and DC fan operating time, smart charger operating time, battery pack charging and discharging data (can be exported by USB flash drive), battery pack charging and discharging curve (can be exported by USB flash drive), current warning information and historical warning data (can be exported by USB flash drive); the operating status includes power input switch status, DC output switch status, AC output switch status, battery pack switch status, static switch status, AC and DC fan operating status and smart charger operating status.

[0150] Data that can be set (password entry): battery pack alarm upper and lower limits, charging voltage, charging current.

[0151] 9.2 Configuration Software Unit

[0152] It is used to communicate data with the BMS main control board, the PLC main control module and the AC / DC inverter using the communication port, and send operating data to the outside (via RS232 serial port or RJ45 network port) to achieve remote management.

[0153] 10. Extended Application

[0154] This system can output (DC) multiple systems in a single-phase (same phase) condition, or it can output (DC) multiple systems in a three-phase input plus a transformer (three-phase to two-phase) (successful cases have been reported). A DC converter can be added to achieve N+1 output (DC) backup, which increases the reliability of system operation. Note: N+1 output (DC) backup: N hosts, 1 backup. When any host loses power, the backup will take over the power supply of the host within 8MS.

[0155] The DC output is converted only once, so it has a very high efficiency of 97-98% and minimal impact on the grid side, FC=99%, THD<=4%, and has obvious energy-saving advantages.

[0156] The device is small in size: it only occupies the standard rack height of 6U (can be installed in a standard rack), and is light in weight: the battery pack adopts 18650 (7C7P) combination module, and the chassis (including the battery pack) weighs 30 kg; the host adopts a modular structure, and the production and assembly are quite simple, suitable for mass production. The weight of the host is less than 20 kg, and the weight of the entire system is about 50 kg. It takes up little space, is easy to carry, and is easy to install and maintain, effectively reducing the comprehensive use cost.

[0157] Therefore, the present invention provides a distributed AC / DC uninterruptible power supply system, in which the battery pack is in an offline mode; adopts high-speed switch switching and a complete battery management system to extend the service life of the battery pack, achieve reliable AC / DC uninterruptible power supply, reduce the occurrence of faults, and realize intelligent power supply management.

[0158] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0159] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A distributed AC / DC uninterruptible power supply system, characterized in that: include: PLC main control module, used for monitoring and controlling power supply; The AC / DC rectifier module is used to rectify the output pulsating power supply, provide the main power supply for the system, and accept the control of the PLC main control module; AC-DC inverter, used for current conversion, to provide uninterrupted AC power to AC power loads; A static switch is used to switch the power supply between the battery pack and the mains through the PLC main control module; the static switch is composed of a static switch control board and a high-speed electronic switch connected in parallel with a high-power relay, and the battery pack is in an offline mode; The DC start-up module is used to start the DC output switch with one button when there is no mains power and AC and DC power are needed, activate the DC start-up function, and realize uninterrupted AC and DC power supply; A four-port isolation module, used to isolate the main circuit and the smart charger using a four-port high-power diode, so as to achieve single-phase current flow between the battery pack and the smart charger; A battery management module, used for providing uninterrupted power supply by using the two battery packs, two BMS main control boards, the smart charger and the battery pack switch; a protection board and a thermostat are provided inside the battery pack, and the BMS main control board is provided with a detection function; Intelligent heat dissipation module, used to automatically dissipate heat using multiple AC and DC fans and thermostats under high-power operation; Human-machine interface and configuration software are used to display operating data and operating status in real time, and to communicate data through the communication interface to achieve remote management; Among them, the PLC main control modules are directly or indirectly connected to the AC / DC rectifier module, the AC / DC inverter, the static switch, the DC starting module, the four-port isolation module, the battery management module, the intelligent heat dissipation module and the human-machine interface and configuration software.

2. A distributed AC / DC uninterruptible power supply system according to claim 1, characterized in that: The PLC main control modules are directly or indirectly connected to the AC / DC rectifier module, the AC / DC inverter, the static switch, the DC start-up module, the four-port isolation module, the battery management module, the intelligent heat dissipation module, the human-machine interface and the configuration software, including: The PLC main control module is connected to the mains, the positive and negative electrodes of the AC / DC rectifier module, the AC / DC inverter, the static switch, the positive electrode of the battery pack, the positive electrode of the input end of the intelligent charger, the intelligent heat dissipation module, the human-machine interface and the configuration software; The input end of the AC / DC rectifier module is connected to the mains, and the output end of the AC / DC rectifier module is connected to the DC power load, the AC / DC inverter, the PLC main control module, the static switch, the battery pack, the intelligent charger and the DC power load; The AC / DC inverter is connected to the mains, the output end of the AC / DC rectifier module, the AC power load, the PLC main control module, the human-machine interface and the configuration software; The static switch is connected to the positive pole of the AC / DC rectifier module, the PLC main control module and the four-port isolation module; The DC starting module is connected to the static switch; The four-port isolation module is connected to the static switch, the output terminal of the smart charger and the battery pack; The battery pack is connected to the BMS main control board, the four-port isolation module and the AC / DC rectifier module, and the BMS main control board is connected to the PLC main control module and the human-machine interface and configuration software; The intelligent heat dissipation module is connected to the PLC main control module; The human-machine interface and configuration software are connected to the AC / DC inverter, the PLC main control module and the battery management module.

3. A distributed AC / DC uninterruptible power supply system according to claim 2, characterized in that: The PLC main control module includes: A mains power normal control unit, used for, when the mains power is normal, using the AC / DC inverter and the AC bypass to output AC power, and then using the smart charger and the output AC power to charge the battery pack until the battery pack is fully charged, and charging the battery pack again when the battery pack is discharged to a set value; A monitoring unit, used for real-time monitoring of the mains voltage, the battery pack voltage, the charge and discharge current, the charge and discharge voltage, the static switch state, the system power input switch state, the DC output switch state, the AC output switch state, the battery pack switch state and the AC / DC inverter switch state; The mains abnormality control unit is used to determine whether the mains is in a high voltage state, a high voltage recovery state, a low voltage state, a low voltage recovery state or a mains disappearance state, and to control the determination result.

4. A distributed AC / DC uninterruptible power supply system according to claim 3, characterized in that: The mains abnormality control unit comprises: The high voltage subunit is used to determine whether the mains power is greater than 245V / AC. If so, a high voltage sound and light warning is issued through the human-machine interface and the configuration software, the static switch is automatically closed, and then the AC / DC rectifier module and the AC / DC inverter are turned off in sequence to realize the power supply of the battery pack and complete the high voltage control of the mains power; The high voltage recovery subunit is used to determine whether the mains power is less than 240V / AC. If so, the AC / DC rectifier module and the AC / DC inverter are turned on first, and then the static switch is automatically disconnected, and finally the smart charger is turned on. The high voltage sound and light warning disappears, the mains power supply is realized, and the high voltage recovery of the mains power is completed; The low voltage subunit is used to determine whether the mains power is less than 190V / AC. If so, a low voltage sound and light warning is issued through the human-machine interface and the configuration software, the intelligent charger is turned off, and then the static switch is automatically closed, and finally the AC / DC rectifier module and the AC / DC inverter are turned off in sequence to realize the power supply of the battery pack and complete the low voltage control of the mains power; The low voltage recovery subunit is used to determine whether the mains power is greater than 198V / AC. If so, the AC / DC rectifier module and the AC / DC inverter are turned on after a delay of 4.7s, and then the static switch is automatically disconnected. Finally, the smart charger is turned on to perform charging maintenance on the battery pack. The low voltage sound and light warning disappears, and the low voltage recovery of the mains power is completed. The mains power disappearance subunit is used to determine whether the mains power disappears. If so, the AC / DC rectifier module, the AC / DC inverter and the smart charger are turned off, the static switch is automatically closed, and the power supply is switched to the battery pack; wherein the switching time is less than 5ms.

5. A distributed AC / DC uninterruptible power supply system according to claim 4, characterized in that: The smart charger works under the control of the PLC main control module. The input voltage of the smart charger is 220V / AC-240V / DC, the output voltage is 0-300V DC continuously adjustable, the output current is 0-4A DC continuously adjustable, and the power is 1200W. The smart charger is internally provided with a smart fan connected to the battery management module. When the battery pack is full, the smart charger automatically shuts down. When the battery needs to be charged, the smart charger automatically turns on.

6. A distributed AC / DC uninterruptible power supply system according to claim 5, characterized in that: The static switch comprises: An opening unit, used to first close the high-speed electronic switch and then turn on the relay to complete the opening of the static switch; The closing unit is used to first close the relay and then disconnect the high-speed electronic switch to complete the closing of the static switch.

7. A distributed AC / DC uninterruptible power supply system according to claim 6, characterized in that: The battery management module comprises: A BMS main control unit, used to monitor the voltage and temperature of the battery management module in real time using the two BMS main control boards. When the monitoring value is greater than a set monitoring threshold, the battery pack switch trips, and the human-machine interface and configuration software issue a tripping sound and light warning, and display that the battery pack switch is in a tripped state. When the monitoring value is less than the monitoring threshold, the battery pack switch is manually restored; A battery capacity control unit, used to determine whether the voltage of the battery management module drops to a preset drop threshold when the battery pack is offline, and if so, to start the smart charger by using the PLC main control module to charge the battery pack until it is fully charged for 15 minutes. During the charging process, when the voltage of the battery pack is abnormal, the smart charger stops charging; The delayed start unit is used to delay the start of the smart charger for 30 seconds when the mains power is turned on after a power outage.

8. A distributed AC / DC uninterruptible power supply system according to claim 7, characterized in that: The intelligent heat dissipation module comprises: A fan start unit, used to determine whether the temperature of the thermostat in the AC / DC rectifier module, the temperature of the thermostat in the smart charger, the charging current, the DC current output, the AC current output or the discharge current is greater than or equal to the corresponding fan start threshold, and if so, automatically start the AC / DC fan, and record and display the running time and running status of the AC / DC fan through the human-machine interface and configuration software; The fan shutoff unit is used to determine whether the temperature of the thermostat in the AC / DC rectifier module, the temperature of the thermostat in the smart charger, the charging current, the DC current output, the AC current output or the discharge current are all less than or equal to the corresponding fan shutoff threshold. If so, the human-machine interface and configuration software record and display the operating time and operating status of the AC / DC fan.

9. A distributed AC / DC uninterruptible power supply system according to claim 8, characterized in that: The human-machine interface and configuration software include: A display unit is used to display operating data and operating status in real time, and to set the threshold, charging voltage and charging current of the battery management module; the operating data includes real-time display of DC output voltage, DC output current, DC output power, AC output voltage, AC output current, AC output power, AC output frequency, battery pack voltage, battery management module voltage and maximum voltage difference, charging current, charging voltage, AC and DC fan operating time, intelligent charger operating time, battery pack charging and discharging data, battery pack charging and discharging curve, current warning information and historical warning data; the operating status includes power input switch status, DC output switch status, AC output switch status, battery pack switch status, static switch status, AC and DC fan operating status and intelligent charger operating status; The configuration software unit is used to communicate data with the BMS main control board, the PLC main control module and the AC / DC inverter using the communication port, and to send operation data to the outside to realize remote management.

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