UPS automatic switching device and method

Abstract

The invention provides a UPS automatic switching device and method, the device comprises an AC-DC conversion module, an AC detection module, an automatic switching module, a battery over-discharge detection module, a lead-acid battery, a charging module and a load power supply module, the commercial power input is connected to the AC-DC conversion module, and the output end of the AC-DC conversion module is connected with the charging module and the automatic switching module; the input end of the AC detection module is connected with commercial power, and the output end of the AC detection module generates an ACOK signal. A battery over-discharge detection module is connected in series between the charging module and the lead-acid battery, and the battery over-discharge detection module outputs an ODP signal; through cooperation of the above modules, a device for controlling the automatic switching module through pure hardware replaces an existing structure controlled by a single-chip microcomputer, a single-chip microcomputer does not need to be arranged, pure hardware control is high in operation safety and reliability, the structure is simple, the production cost is low, an anti-backflow circuit is not needed, and the production cost is further reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of power supply, and more specifically, to a UPS automatic switching device and method. Background Art

[0002] UPS (Uninterruptible Power Supply) is a control module that provides temporary power to equipment through batteries / generators when the power grid fails. The UPS switching system is responsible for automatically or manually switching between the main power supply (mains power) and the backup power supply (battery / generator). The core goal is to achieve zero interruption or minimum power outage time.

[0003] The closest technology to the existing technology, authorization announcement number: CN114243892B, an automatic power switching device and method, including a first switching circuit, a second switching circuit and a sampling judgment circuit; the sampling judgment circuit is respectively connected to the battery, the first switching circuit, and the second switching circuit, for collecting the output voltage of the battery to obtain a sampling voltage signal, and judging whether the sampling voltage signal is lower than the voltage setting lower limit, and when the sampling voltage signal is lower than the voltage setting lower limit, outputting a control signal to the first switching circuit, and outputting a control signal and a sampling voltage signal to the second switching circuit; when the control signal is a high-level signal, the first switching circuit works; when the control signal is a low-level signal, the second switching circuit works; the first switching circuit is used to use a mains power supply to charge the battery; the second switching circuit is used to use a generator to charge the battery according to the sampling voltage signal.

[0004] Existing power switching methods rely on single-chip microcomputers for control, which are prone to software failure risks, such as program crashes and logical errors, which may cause system failure and affect the continuous power supply of the equipment, and are costly.

[0005] In view of this, the present invention proposes a low-cost UPS automatic switching device and method that is purely hardware-logically controlled. Summary of the invention

[0006] The purpose of the present invention is to provide a UPS automatic switching device and method which is purely hardware logic controlled and low in cost.

[0007] A UPS automatic switching device, comprising an AC-DC conversion module, an AC detection module, an automatic switching module, a battery over-discharge detection module, a lead-acid battery, a charging module, and a load power supply module, characterized in that: The mains input is connected to the AC-DC conversion module, and the output end of the AC-DC conversion module is connected to the charging module and the automatic switching module respectively; The input end of the AC detection module is connected to the mains, and the output end of the AC detection module generates an AC_OK signal, where AC_OK=0 indicates that the mains is normal, and AC_OK=1 indicates that the mains is missing; A battery over-discharge detection module is connected in series between the charging module and the lead-acid battery, and the battery over-discharge detection module outputs an ODP signal, wherein ODP=0 indicates that the battery is over-discharged, and ODP=1 indicates that the battery is normal; The output end of the automatic switching module is connected to the load power supply module. The automatic switching module includes a relay and a logic control unit. The automatic switching module controls the switching of the relay contacts based on the AC_OK and ODP signals received by the logic control unit. When AC_OK=0, the relay of the automatic switching module keeps the NC normally closed contact turned on and outputs the AC power first. When AC_OK=1 and ODP=1, the relay of the automatic switching module is energized, the NO normally open contact is turned on, and the power supply is switched to the lead-acid battery. When ODP=0, regardless of the AC_OK status, the relay of the automatic switching module keeps the NC normally closed contact turned on or cuts off the lead-acid battery power supply.

[0008] In some embodiments, a battery reverse connection prevention module is provided between the charging module and the lead-acid battery, and the battery reverse connection prevention module is used to ensure that the relay in the automatic switching module does not malfunction when the battery is reversely connected.

[0009] In some embodiments, the output end of the automatic switching module is connected to the load power supply module, and the automatic switching module outputs an RLY signal. When ODP=0 and AC_OK=0, RLY=0, i.e., AC power output; when ODP=0 and AC_OK=1, RLY=0, i.e., AC power output; when ODP=10 and AC_OK=0, RLY=0, i.e., AC power output; when ODP=1 and AC_OK=1, RLY=1, i.e., lead-acid battery output.

[0010] In some embodiments, the battery over-discharge detection module uses a hysteresis comparator circuit, whose low threshold voltage is 10.5V±5%, and whose high threshold voltage is 12.20V±5%, which is achieved by voltage division through a resistor network.

[0011] In some implementations, the logic control unit of the automatic switching module is a SN74AHC1608DBVR chip.

[0012] In some embodiments, the relay is a double-pole double-throw type, model SLA-12VDC-SL-C, its coil driving voltage is 12V, the contact capacity is ≥10A, the NC normally closed contact is connected to the output end of the AC-DC conversion module, and the NO normally open contact is connected to the lead-acid battery.

[0013] In some implementations, the AC detection module includes a multi-stage voltage-dividing resistor and a rectifier diode, and the AC detection module is used to convert the AC input into an AC_OK DC logic level signal.

[0014] In some embodiments, the charging module includes a current limiting resistor and a filter capacitor, the input end of the charging module is connected to the output end of the AC-DC conversion module, and the output end of the charging module is connected to the positive electrode of the lead-acid battery.

[0015] A UPS automatic switching method, characterized in that it comprises the following steps: The AC detection module detects the mains power status and generates an AC_OK signal; The lead-acid battery voltage is detected by a hysteresis comparator to generate an ODP signal; The load power supply module is controlled by the automatic switching module. The automatic switching module works based on AC_OK and ODP signals. When AC_OK=0, the relay of the automatic switching module keeps the NC normally closed contact turned on, and the load power supply module outputs the AC power first. When AC_OK=1 and ODP=1, the relay of the automatic switching module is energized, the NO normally open contact is turned on, and the load power supply module switches to the lead-acid battery for power supply; when ODP=0, regardless of the AC_OK status, the relay of the automatic switching module keeps the NC normally closed contact turned on or cuts off the lead-acid battery power supply.

[0016] Beneficial effects of the invention: The invention proposes a UPS automatic switching device and method, comprising an AC-DC conversion module, an AC detection module, an automatic switching module, a battery over-discharge detection module, a lead-acid battery, a charging module, and a load power supply module, wherein the AC power input is connected to the AC-DC conversion module, and the output end of the AC-DC conversion module is respectively connected to the charging module and the automatic switching module; the input end of the AC detection module is connected to the AC power, and the output end of the AC detection module generates an AC_OK signal, wherein AC_OK=0 indicates that the AC power is normal, and AC_OK=1 indicates that the AC power is missing; a battery over-discharge detection module is connected in series between the charging module and the lead-acid battery, and the battery over-discharge detection module outputs an ODP signal; the output end of the automatic switching module is connected to the load power supply module, the automatic switching module comprises a relay and a logic control unit, and the automatic switching module controls the switching of the relay contacts based on the AC_OK and ODP signals received by the logic control unit. Through the cooperation of the above modules, a device for purely hardware-controlled automatic switching modules replaces the existing structure controlled by a single-chip microcomputer, and there is no need to set a single-chip microcomputer. The pure hardware control has high safety and reliability, a simple structure and low production cost, and no anti-backfeed circuit is required, thereby further reducing the production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the connection structure of the UPS automatic switching device of the present application.

[0018] Figure 2 This is the logic truth table of the automatic switching module of this application.

[0019] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0020] The following examples are described to assist the understanding of the present application, and the examples are not and should not be interpreted in any way as limiting the scope of protection of the present application.

[0021] In the following description, those skilled in the art will recognize that throughout this discussion, components may be described as separate functional units (which may include sub-units), but those skilled in the art will recognize that various components or portions thereof may be divided into separate components or may be integrated together (including within a single system or component).

[0022] At the same time, the connections between components or systems are not intended to be limited to direct connections, rather, the data between these components may be modified, reformatted, or otherwise changed by intermediate components. In addition, additional or fewer connections may be used. It should also be noted that the terms "coupled," "connected," or "input" should be understood to include direct connections, indirect connections through one or more intermediate devices, and wireless connections. Embodiment 1:

[0023] like Figure 1 As shown, it is a schematic diagram of the connection structure of the UPS automatic switching device of the present application, a UPS automatic switching device, including an AC-DC conversion module, an AC detection module, an automatic switching module, a battery over-discharge detection module, a lead-acid battery, a charging module, and a load power supply module, characterized in that: The mains input is connected to the AC-DC conversion module, and the output end of the AC-DC conversion module is connected to the charging module and the automatic switching module respectively; The input end of the AC detection module is connected to the mains, and the output end of the AC detection module generates an AC_OK signal, where AC_OK=0 indicates that the mains is normal, and AC_OK=1 indicates that the mains is missing; A battery over-discharge detection module is connected in series between the charging module and the lead-acid battery, and the battery over-discharge detection module outputs an ODP signal, wherein ODP=0 indicates that the battery is over-discharged, and ODP=1 indicates that the battery is normal; The output end of the automatic switching module is connected to the load power supply module. The automatic switching module includes a relay and a logic control unit. The automatic switching module controls the switching of the relay contacts based on the AC_OK and ODP signals received by the logic control unit. When AC_OK=0, the relay of the automatic switching module keeps the NC normally closed contact turned on and outputs the AC power first. When AC_OK=1 and ODP=1, the relay of the automatic switching module is energized, the NO normally open contact is turned on, and the power supply is switched to the lead-acid battery. When ODP=0, regardless of the AC_OK status, the relay of the automatic switching module keeps the NC normally closed contact turned on or cuts off the lead-acid battery power supply.

[0024] A battery reverse connection prevention module is provided between the charging module and the lead-acid battery, and the battery reverse connection prevention module is used to ensure that the relay in the automatic switching module will not malfunction when the battery is reversely connected.

[0025] like Figure 2 As shown, this is the logic truth table of the automatic switching module of the present application. The output end of the automatic switching module is connected to the load power supply module, and the automatic switching module outputs the RLY signal. When ODP=0 and AC_OK=0, RLY=0 means AC power output; when ODP=0 and AC_OK=1, RLY=0 means AC power output; when ODP=10 and AC_OK=0, RLY=0 means AC power output; when ODP=1 and AC_OK=1, RLY=1 means lead-acid battery output.

[0026] The battery over-discharge detection module adopts a hysteresis comparator circuit, whose low threshold voltage is 10.5V±5% and high threshold voltage is 12.20V±5%, which is achieved by voltage division through a resistor network.

[0027] The logic control unit of the automatic switching module is a SN74AHC1608DBVR chip.

[0028] The relay is a double-pole double-throw type, model SLA-12VDC-SL-C, with a coil drive voltage of 12V, a contact capacity ≥10A, an NC normally closed contact connected to the output end of the AC-DC conversion module, and a NO normally open contact connected to a lead-acid battery.

[0029] The AC detection module includes a multi-stage voltage-dividing resistor and a rectifier diode, and is used to convert the AC input into an AC_OK DC logic level signal.

[0030] The charging module comprises a current limiting resistor and a filter capacitor, the input end of the charging module is connected to the output end of the AC-DC conversion module, and the output end of the charging module is connected to the positive electrode of the lead-acid battery.

[0031] A UPS automatic switching method, characterized in that it comprises the following steps: The AC detection module detects the mains power status and generates an AC_OK signal; The lead-acid battery voltage is detected by a hysteresis comparator to generate an ODP signal; The load power supply module is controlled by the automatic switching module. The automatic switching module works based on AC_OK and ODP signals. When AC_OK=0, the relay of the automatic switching module keeps the NC normally closed contact turned on, and the load power supply module outputs the AC power first. When AC_OK=1 and ODP=1, the relay of the automatic switching module is energized, the NO normally open contact is turned on, and the load power supply module switches to the lead-acid battery for power supply; when ODP=0, regardless of the AC_OK status, the relay of the automatic switching module keeps the NC normally closed contact turned on or cuts off the lead-acid battery power supply.

[0032] Beneficial effects of the invention: The invention proposes a UPS automatic switching device and method, comprising an AC-DC conversion module, an AC detection module, an automatic switching module, a battery over-discharge detection module, a lead-acid battery, a charging module, and a load power supply module, wherein the AC power input is connected to the AC-DC conversion module, and the output end of the AC-DC conversion module is respectively connected to the charging module and the automatic switching module; the input end of the AC detection module is connected to the AC power, and the output end of the AC detection module generates an AC_OK signal, wherein AC_OK=0 indicates that the AC power is normal, and AC_OK=1 indicates that the AC power is missing; a battery over-discharge detection module is connected in series between the charging module and the lead-acid battery, and the battery over-discharge detection module outputs an ODP signal; the output end of the automatic switching module is connected to the load power supply module, the automatic switching module comprises a relay and a logic control unit, and the automatic switching module controls the switching of the relay contacts based on the AC_OK and ODP signals received by the logic control unit. Through the cooperation of the above modules, a device for purely hardware-controlled automatic switching modules replaces the existing structure controlled by a single-chip microcomputer, and there is no need to set a single-chip microcomputer. The pure hardware control has high safety and reliability, a simple structure and low production cost, and no anti-backfeed circuit is required, thereby further reducing the production cost.

[0033] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A UPS automatic switching device, comprising an AC-DC conversion module, an AC detection module, an automatic switching module, a battery over-discharge detection module, a lead-acid battery, a charging module, and a load power supply module, characterized in that: The mains input is connected to the AC-DC conversion module, and the output end of the AC-DC conversion module is connected to the charging module and the automatic switching module respectively; The input end of the AC detection module is connected to the mains, and the output end of the AC detection module generates an AC_OK signal, where AC_OK=0 indicates that the mains is normal, and AC_OK=1 indicates that the mains is missing; A battery over-discharge detection module is connected in series between the charging module and the lead-acid battery, and the battery over-discharge detection module outputs an ODP signal, wherein ODP=0 indicates that the battery is over-discharged, and ODP=1 indicates that the battery is normal; The output end of the automatic switching module is connected to the load power supply module. The automatic switching module includes a relay and a logic control unit. The automatic switching module controls the switching of the relay contacts based on the AC_OK and ODP signals received by the logic control unit. When AC_OK=0, the relay of the automatic switching module keeps the NC normally closed contact turned on and outputs the AC power first. When AC_OK=1 and ODP=1, the relay of the automatic switching module is energized, the NO normally open contact is turned on, and the power supply is switched to the lead-acid battery. When ODP=0, regardless of the AC_OK status, the relay of the automatic switching module keeps the NC normally closed contact turned on or cuts off the lead-acid battery power supply.

2. The UPS automatic switching device according to claim 1, characterized in that: A battery reverse connection prevention module is provided between the charging module and the lead-acid battery, and the battery reverse connection prevention module is used to ensure that the relay in the automatic switching module will not malfunction when the battery is reversely connected.

3. The UPS automatic switching device according to claim 1, characterized in that: The output end of the automatic switching module is connected to the load power supply module, and the automatic switching module outputs the RLY signal. When ODP=0 and AC_OK=0, RLY=0 means AC power output; when ODP=0 and AC_OK=1, RLY=0 means AC power output; when ODP=10 and AC_OK=0, RLY=0 means AC power output; when ODP=1 and AC_OK=1, RLY=1 means lead-acid battery output.

4. The UPS automatic switching device according to claim 1, characterized in that: The battery over-discharge detection module adopts a hysteresis comparator circuit, whose low threshold voltage is 10.5V±5% and high threshold voltage is 12.20V±5%, which is achieved by voltage division through a resistor network.

5. The UPS automatic switching device according to claim 1, characterized in that: The logic control unit of the automatic switching module is a SN74AHC1608DBVR chip.

6. The UPS automatic switching device according to claim 1, characterized in that: The relay is a double-pole double-throw type, model SLA-12VDC-SL-C, with a coil drive voltage of 12V, a contact capacity ≥10A, an NC normally closed contact connected to the output end of the AC-DC conversion module, and a NO normally open contact connected to a lead-acid battery.

7. The UPS automatic switching device according to claim 1, characterized in that: The AC detection module includes a multi-stage voltage-dividing resistor and a rectifier diode, and is used to convert the AC input into an AC_OK DC logic level signal.

8. The UPS automatic switching device according to claim 1, characterized in that: The charging module comprises a current limiting resistor and a filter capacitor, the input end of the charging module is connected to the output end of the AC-DC conversion module, and the output end of the charging module is connected to the positive electrode of the lead-acid battery.

9. A UPS automatic switching method using the device according to any one of claims 1 to 8, characterized in that: The following steps are involved: The AC detection module detects the mains power status and generates an AC_OK signal; The lead-acid battery voltage is detected by a hysteresis comparator to generate an ODP signal; The load power supply module is controlled by the automatic switching module. The automatic switching module works based on AC_OK and ODP signals. When AC_OK=0, the relay of the automatic switching module keeps the NC normally closed contact turned on, and the load power supply module outputs the AC power first. When AC_OK=1 and ODP=1, the relay of the automatic switching module is energized, the NO normally open contact is turned on, and the load power supply module switches to the lead-acid battery for power supply; when ODP=0, regardless of the AC_OK status, the relay of the automatic switching module keeps the NC normally closed contact turned on or cuts off the lead-acid battery power supply.

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