Low voltage protection device for batteries

Abstract

The present invention discloses a low voltage protection device for a battery, comprising: a main power supply circuit, the main power supply circuit is connected to a battery and a control system respectively; a starting circuit for controlling the main power supply circuit to be turned on so that the battery supplies power to the control system; a low voltage cancellation circuit for controlling the starting circuit to be disconnected when the voltage of the battery is less than the working voltage of the control system so that the main power supply circuit is disconnected; and a recovery circuit for controlling the starting circuit to be turned on under user triggering. After the main power supply circuit is disconnected, the device needs to be triggered by the user to control the main power supply circuit to be turned on through the starting circuit so that the battery supplies power to the control system, thereby effectively preventing the low voltage oscillation caused by the battery directly supplying power to the control system and avoiding damage to the control system.

Description

Technical Field

[0001] The invention relates to the technical field of battery power supply, and in particular to a low voltage protection device for a battery. Background Art

[0002] In the control field, there are a large number of applications that use batteries as backup power to directly power the control system.

[0003] When the battery power is consumed to a certain extent, the battery voltage will drop below the control system's allowable voltage, and the control system will automatically stop working. After the control system stops working, the battery voltage will gradually increase due to the significant reduction in battery load, and the battery's own power will be restored. The battery voltage will meet the control system's working requirements again, and the control system will start working again. This process is repeated back and forth, which will cause damage to the control system. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, the purpose of the present invention is to propose a low-voltage protection device for a battery. After the main power supply circuit is disconnected, the device needs to be triggered by the user to control the main power supply circuit to be turned on through the starting circuit, so that the battery can power the control system, thereby effectively preventing low-voltage oscillations caused by the battery directly powering the control system and avoiding damage to the control system.

[0006] To achieve the above-mentioned purpose, an embodiment of one aspect of the present invention proposes a low-voltage protection device for a battery, comprising: a main power supply circuit, which is connected to the battery and the control system respectively; a starting circuit for controlling the main power supply circuit to be turned on so that the battery supplies power to the control system; a low-voltage cancellation circuit for controlling the starting circuit to be disconnected when the voltage of the battery is lower than the working voltage of the control system so as to disconnect the main power supply circuit; and a recovery circuit for controlling the starting circuit to be turned on when triggered by a user.

[0007] According to the low-voltage protection device for a battery in an embodiment of the present invention, a main power supply circuit is connected to a battery and a control system respectively, a starting circuit controls the main power supply circuit to be turned on so that the battery supplies power to the control system, a low-voltage cancellation circuit controls the starting circuit to be disconnected when the voltage of the battery is lower than the working voltage of the control system so that the main power supply circuit is disconnected, and a recovery circuit controls the starting circuit to be turned on when triggered by a user, so that after the main power supply circuit is disconnected, the main power supply circuit can be controlled to be turned on through the starting circuit when triggered by a user so that the battery supplies power to the control system, thereby effectively preventing low-voltage oscillation caused by the battery directly supplying power to the control system and avoiding damage to the control system.

[0008] According to one embodiment of the present invention, the starting circuit includes: a starting switch, a first normally open contact of a first relay and a coil of the first relay, the first normally open contact of the first relay being connected in parallel with the starting switch and then in series with the coil of the first relay, wherein when the starting switch is closed, the first normally open contact of the first relay is closed, the first normally open contact of the first relay and the coil of the first relay form a self-holding circuit, and the starting circuit is in a continuously conducting state.

[0009] According to one embodiment of the present invention, the main power supply circuit comprises: a second normally open contact of the first relay, wherein when the starting circuit is in a continuously conducting state, the main power supply circuit is in a continuously conducting state.

[0010] According to one embodiment of the present invention, the low-voltage cancellation circuit includes: a detection switch and a coil of a second relay, the detection switch is connected in series with the coil of the second relay; the recovery circuit includes: a coil of a third relay, a normally open contact of the third relay and a first normally open contact of the second relay, the normally open contact of the third relay is connected in parallel with the first normally open contact of the second relay and then connected in series with the coil of the third relay; the starting circuit also includes: a second normally open contact of the second relay and a normally closed contact of the third relay, the first normally open contact of the first relay is connected in parallel with the starting switch and then connected in series with the second normally open contact of the second relay, the second normally open contact of the second relay is connected in parallel with the normally closed contact of the third relay, wherein when the voltage of the battery is greater than or equal to the working voltage of the control system, the detection switch is closed; when the voltage of the battery is less than the working voltage of the control system, the detection switch is disconnected, the starting circuit is disconnected, and the main power supply circuit is disconnected.

[0011] According to an embodiment of the present invention, the recovery circuit further includes: a reset switch, the reset switch is a normally closed switch, the reset switch is interlocked with the start switch, wherein when the reset switch is opened, the start switch is closed.

[0012] According to an embodiment of the present invention, the start switch and the reset switch constitute a start reset button. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a block diagram of a low voltage protection device for a battery according to an embodiment of the present invention;

[0014] Figure 2 is a circuit diagram of a low voltage protection device for a battery according to an embodiment of the present invention;

[0015] Figure 3 is a circuit diagram of a low voltage protection device for a battery according to another embodiment of the present invention. DETAILED DESCRIPTION

[0016] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0017] The low voltage protection device for a battery according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0018] Figure 1 1 is a block diagram of a low voltage protection device for a battery according to an embodiment of the present invention. Figure 1 As shown, the low voltage protection device of the battery includes: a main power supply circuit 10, a starting circuit 20, a low voltage cancellation circuit 30 and a recovery circuit 40.

[0019] Among them, the main power supply circuit 10 is connected to the battery and the control system respectively, the starting circuit 20 is used to control the main power supply circuit 10 to be turned on so that the battery can power the control system, the low voltage cancellation circuit 30 is used to control the starting circuit 20 to be disconnected when the battery voltage is lower than the working voltage of the control system so that the main power supply circuit 10 is disconnected, and the recovery circuit 40 is used to control the starting circuit 20 to be turned on when triggered by the user.

[0020] Specifically, when the control system needs to be powered on, the user triggers the recovery circuit 40 to turn on the start circuit 20. After the start circuit 20 is turned on, the start circuit 20 controls the main power supply circuit 10 to be turned on. At this time, the battery powers the control system and the control system starts to work.

[0021] During the operation of the control system, as the battery power is consumed, the battery voltage will gradually decrease. When the battery voltage is lower than the voltage allowed by the control system, the control system will send a contact signal to the low voltage cancellation circuit 30. After receiving the contact signal, the low voltage cancellation circuit 30 controls the start circuit 20 to be disconnected, and the main power supply circuit 10 is also disconnected, and the connection line between the battery and the control system is cut off. Only when the user triggers the recovery circuit 40 again to turn on the start circuit 20, the main power supply circuit 10 will be turned on, and the battery can supply power to the control system at this time, thereby effectively avoiding the problem of back and forth power supply caused by the automatic power supply to the control system when the battery voltage increases, causing damage to the control system.

[0022] It should be noted that in this embodiment, the signal with low power supply voltage output by the control system (ie, the contact signal) is the most accurate and utilizes the range of external power supply voltage to the maximum extent, which is very beneficial to improving the adaptability of the control system.

[0023] According to one embodiment of the present invention, Figure 2 As shown, the starting circuit 20 includes: a starting switch SF, a first normally open contact KA11 of a first relay and a coil KA1 of the first relay. The first normally open contact KA11 of the first relay is connected in parallel with the starting switch SF and then in series with the coil KA1 of the first relay. When the starting switch SF is closed, the coil KA1 of the first relay is energized, causing the first normally open contact KA11 of the first relay to close. As a result, the first normally open contact KA11 of the first relay and the coil KA1 of the first relay form a self-holding circuit, and the starting circuit 20 is in a continuously on state.

[0024] Furthermore, if Figure 2 As shown, the main power supply circuit 10 includes: a second normally open contact KA12 of the first relay, wherein when the starting circuit 20 is in a continuously conducting state, the main power supply circuit 10 is in a continuously conducting state.

[0025] Specifically, when the user triggers the recovery circuit 40 to close the start switch SF, the coil KA1 of the first relay will be energized, causing the first normally open contact KA11 of the first relay and the second normally open contact KA12 of the first relay to be closed, the main power supply circuit 10 is turned on, and the battery starts to supply power to the control system. Since the coil KA1 of the first relay and the first normally open contact KA11 of the first relay form a self-holding circuit, even if the start switch SF is released, the second normally open contact KA12 of the first relay is still in a closed state, and the battery will continue to supply power to the control system. During the startup of the control system, if low voltage occurs, the battery can be manually cut off to avoid opening and closing oscillation.

[0026] According to one embodiment of the present invention, Figure 3 As shown, the low voltage cancellation circuit 30 includes: a detection switch P and a coil KA2 of a second relay, and the detection switch P is connected in series with the coil KA2 of the second relay.

[0027] The recovery circuit 40 includes: a coil KA3 of a third relay, a normally open contact KA31 of the third relay and a first normally open contact KA21 of the second relay. The normally open contact KA31 of the third relay is connected in parallel with the first normally open contact KA21 of the second relay and then in series with the coil KA3 of the third relay.

[0028] The starting circuit 20 also includes: a second normally open contact KA22 of the second relay and a normally closed contact KA32 of the third relay. The first normally open contact KA11 of the first relay is connected in parallel with the starting switch SF and then in series with the second normally open contact KA22 of the second relay. The second normally open contact KA22 of the second relay is connected in parallel with the normally closed contact KA32 of the third relay.

[0029] Among them, when the battery voltage is greater than or equal to the working voltage of the control system, the detection switch P is closed; when the battery voltage is less than the working voltage of the control system, the detection switch P is disconnected, the starting circuit 20 is disconnected, and the main power supply circuit 10 is disconnected.

[0030] Furthermore, if Figure 3 As shown, the recovery circuit 40 further includes: a reset switch SS, which is a normally closed switch. The reset switch SS is interlocked with the start switch SF, wherein when the reset switch SS is opened, the start switch SF is closed.

[0031] Specifically, Figure 3 As shown, when the battery is needed to power the control system, the user presses the reset switch SS, at which time the reset switch SS is disconnected, the start switch SF is closed, the coil KA1 of the first relay is energized, the first normally open contact KA11 of the first relay and the second normally open contact KA12 of the first relay are both closed, and the battery powers the control system through the second normally open contact KA12 of the first relay.

[0032] When the control system is powered on and starts working, the detection switch P in the low voltage cancellation circuit 30 will be closed (whether the detection switch P is closed is controlled by whether the control system is powered on), the coil KA2 of the second relay is energized, and the second normally open contact KA22 of the second relay is closed.

[0033] When the user releases the reset switch SS, the reset switch SS is closed and the start switch SF is opened. Although the start switch SF is opened, since the first normally open contact KA11 of the first relay and the second normally open contact KA22 of the second relay are both in a closed state, the coil KA1 of the first relay still has current flowing through it, and the second normally open contact KA12 of the first relay is still in a closed state, and the battery continues to supply power to the control system. Therefore, the control system will not be powered off because the user releases the reset switch SS. In practical applications, the start reset button can replace the start switch SF and the reset switch SS.

[0034] When the user releases the reset switch SS, the reset switch SS is closed, so the coil KA3 of the third relay is energized, the normally open contact KA31 of the third relay is closed, and the normally closed contact KA32 of the third relay is disconnected. At this time, although the normally closed contact KA32 of the third relay is disconnected, the second normally open contact KA22 of the second relay is closed, so the coil KA1 of the first relay is not affected.

[0035] At this point, the first to third relays and the control system are all in an energized working state.

[0036] During the operation of the control system, when the battery voltage is lower than the allowable operating voltage of the control system, the control system will shut down, and the detection switch P will automatically disconnect, the coil KA2 of the second relay will lose power, and the second normally open contact KA22 of the second relay will disconnect. Since the normally closed contact KA32 of the third relay is disconnected at this time, the coil KA1 of the first relay will lose power, and the second normally open contact KA12 of the first relay will disconnect, which means that the connection line between the battery and the control system is disconnected. Therefore, even if the battery voltage rises again after a period of time, the control system will not restart unless the user presses the reset switch SS again, thereby effectively avoiding the low voltage oscillation caused by the battery directly supplying power to the control system, which in turn causes damage to the control system.

[0037] It can be understood that the purpose of connecting the normally open contact KA31 of the third relay in parallel with the first normally open contact KA21 of the second relay is to ensure that after the coil KA2 of the second relay loses power, the coil KA3 of the third relay is still in an energized state and the normally closed contact KA32 of the third relay is in an open state. Otherwise, when the coil KA2 of the second relay loses power and the first normally open contact KA21 of the second relay is disconnected, the normally closed contact KA32 of the third relay is in a closed state again due to the loss of power in the coil KA3 of the third relay. At this time, the coil KA1 of the first relay cannot lose power, and the connection line between the battery and the control system cannot be cut off.

[0038] Therefore, the low voltage protection device of the battery in the embodiment of the present invention first uses the manual start reset button to start the relay self-holding circuit so that the battery can supply power to the control system. Then, after the control system is powered on and started, a contact signal is output, and the self-holding circuit is cut off by this contact, and the main power supply circuit is kept in the on state by this contact. When the voltage of the battery is lower than the working voltage of the control system, the contact is disconnected, the self-holding circuit relying on this contact is disconnected, and the power supply of the control system is cut off. Only when the reset button is manually restarted on site can the power be restored, which effectively avoids the problem of power supply back and forth caused by automatic power supply to the control system when the battery voltage rises, causing damage to the control system.

[0039] It should be noted that, in an embodiment of the present invention, the first to third relays and the control system can be powered by the same battery (L, N). At this time, the operating voltage range of the relay is much smaller than the operating voltage range allowed by the control system, so that when the control system cannot work due to low battery voltage, the relay can continue to work.

[0040] In summary, according to the low-voltage protection device for a battery of the present invention, a main power supply circuit is connected to a battery and a control system respectively, a starting circuit controls the main power supply circuit to be turned on so that the battery supplies power to the control system, a low-voltage cancellation circuit controls the starting circuit to be disconnected when the voltage of the battery is lower than the working voltage of the control system so that the main power supply circuit is disconnected, and a recovery circuit controls the starting circuit to be turned on when triggered by a user, so that after the main power supply circuit is disconnected, the main power supply circuit can be controlled to be turned on through the starting circuit when triggered by a user so that the battery supplies power to the control system, thereby effectively preventing low-voltage oscillation caused by the battery directly supplying power to the control system and avoiding damage to the control system, and the device has low cost, high reliability and strong practicality.

[0041] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0042] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0043] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0045] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0046] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A low voltage protection device for a battery, characterized in that: include: A main power supply circuit, the main power supply circuit is connected to the battery and the control system respectively; A starting circuit for controlling the conduction of the main power supply circuit so that the battery can supply power to the control system; A low-voltage cancellation circuit for controlling the start circuit to disconnect when the voltage of the battery is lower than the operating voltage of the control system so as to disconnect the main power supply circuit; as well as A recovery circuit for controlling the start-up circuit to be turned on when triggered by a user; The startup circuit comprises: A starting switch, a first normally open contact of a first relay and a coil of the first relay, wherein the first normally open contact of the first relay is connected in parallel with the starting switch and then in series with the coil of the first relay, wherein: When the start switch is closed, the first normally open contact of the first relay is closed, the first normally open contact of the first relay and the coil of the first relay form a self-holding circuit, and the start circuit is in a continuously conducting state; When the battery voltage is lower than the voltage allowed by the control system, the control system will send a contact signal to the low-voltage cancellation circuit. After receiving the contact signal, the low-voltage cancellation circuit controls the start circuit to be disconnected, and the main power supply circuit is also disconnected. The connection line between the battery and the control system is cut off. Only when the user triggers the recovery circuit again to turn on the start circuit, the main power supply circuit will be turned on, and the battery can supply power to the control system at this time; The low voltage cancellation circuit comprises: a detection switch and a coil of a second relay, wherein the detection switch is connected in series with the coil of the second relay; The recovery circuit comprises: a coil of a third relay, a normally open contact of the third relay and a first normally open contact of the second relay, wherein the normally open contact of the third relay is connected in parallel with the first normally open contact of the second relay and then connected in series with the coil of the third relay; The starting circuit further includes: a second normally open contact of the second relay and a normally closed contact of the third relay, the first normally open contact of the first relay is connected in parallel with the starting switch and then connected in series with the second normally open contact of the second relay, the second normally open contact of the second relay is connected in parallel with the normally closed contact of the third relay, wherein, When the voltage of the battery is greater than or equal to the working voltage of the control system, the detection switch is closed; When the voltage of the battery is lower than the operating voltage of the control system, the detection switch is disconnected, the start-up circuit is disconnected, and the main power supply circuit is disconnected.

2. The low voltage protection device for a battery according to claim 1, characterized in that: The main power supply circuit comprises: The second normally open contact of the first relay, wherein when the starting circuit is in a continuously conducting state, the main power supply circuit is in a continuously conducting state.

3. The low voltage protection device for a battery according to claim 1, characterized in that: The recovery circuit further includes: A reset switch, wherein the reset switch is a normally closed switch, and the reset switch is interlocked with the start switch, wherein when the reset switch is opened, the start switch is closed.

4. The low voltage protection device for a battery according to claim 3, characterized in that: The start switch and the reset switch constitute a start reset button.

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