Compatible dual-power switching circuit

Abstract

The utility model relates to the technical field of power supply circuits, in particular to a compatible dual-power supply switching circuit, which comprises a main power supply switch, an auxiliary power supply switch, a first power supply monitor, a second power supply monitor, a first contactor, a second contactor, a first relay, a second relay, a change-over switch and a power supply output end, the first contactor is provided with a first contact coil and a first contact switch; the second contactor is provided with a second contact coil and a second contact switch; the first relay comprises a first relay coil, a first relay normally open switch and a first relay normally closed switch; the second relay comprises a second relay coil and a second relay normally open switch; a first interlocking switch and a second interlocking switch are further included. According to the utility model, by arranging the change-over switch and controlling the on-off of the change-over switch, the automatic switching and automatic recovery function and the automatic switching and non-automatic recovery function can be realized.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply circuits, and particularly relates to a compatible dual-power switching circuit. Background Art

[0002] With the continuous development of modern industrial technologies, more and more industrial control scenarios gradually require dual-power supply for applied electrical devices and automatic dual-power switching. Therefore, dual-power automatic transfer switches are increasingly used in the power supply control of industrial control products. Among them, the CC-level dual-power automatic transfer, as one of the most widely used dual-power switching schemes, is widely favored by the market because its main structure is built by contactors, and the switching function can be composed of a secondary circuit by a relay or a logic control module to complete the control function, with a simple form and low price.

[0003] The commonly used CC-level dual-power switching circuit in the current industry often only has a simple "self-switching and self-restoring" function. In actual engineering applications, there must be a corresponding switching time gap during the switching process of the main and standby power supplies. Therefore, there is often a certain power fluctuation during the switching process. For some specific occasions or application scenarios, it is often required to minimize the number of power supply switches as much as possible. When the main power supply fails, it is required to immediately switch to the standby power supply. Even if the main power supply returns to normal later, it is required to continue using the standby power supply to avoid the impact of frequent power supply switching on the use effect of electrical equipment and increase risks. In short, in actual engineering applications, it is often required that the dual-power circuit can also achieve the "self-switching and non-self-restoring" function, or flexibly select and switch between these two modes according to actual engineering needs. However, the current traditional CC-level switching circuit cannot meet this requirement and has certain application limitations. Summary of the Invention

[0004] The purpose of the utility model is to overcome the above-mentioned disadvantages and provide a compatible dual-power switching circuit.

[0005] To achieve the above purpose, the specific scheme of the utility model is as follows: A compatible dual-power switching circuit includes a main power switch, a secondary power switch, a first power monitor, a second power monitor, a first contactor, a second contactor, a first relay, a second relay, a switching switch, and a power output terminal;

[0006] The first power monitor is provided with a first normally open power switch; the second power monitor is provided with a second normally open power switch; the first contactor is provided with a first contact coil and a first contact switch; the second contactor is provided with a second contact coil and a second contact switch; the first relay includes a first relay coil, a first normally open relay switch, and a first normally closed relay switch; the second relay includes a second relay coil and a second normally open relay switch;

[0007] It further includes a first interlock switch cooperating with the first contact switch and a second interlock switch cooperating with the second contact switch;

[0008] The main power switch is connected to the power output terminal through the first contact switch; the auxiliary power switch is connected to the power output terminal through the second contact switch; the input end of the first power monitor is connected to the main power switch; the input end of the second power monitor is connected to the auxiliary power switch; one end of the first normally-open power switch is connected to the main power switch; the other end of the first normally-open power switch is sequentially connected to the main power switch through the second interlock switch and the first relay coil; the other end of the first normally-open power switch is sequentially connected to the main power switch through the first normally-open relay switch and the first contact coil; the first normally-closed relay switch, the first interlock switch, the second contact coil, the second relay coil and the second normally-open relay switch form a self-locking circuit; the changeover switch is used to control the on / off of the self-locking circuit; the self-locking circuit is connected to the auxiliary power switch through the second normally-open power switch.

[0009] The utility model is further arranged such that both the main power switch and the auxiliary power switch are circuit breakers or disconnecting switches.

[0010] The utility model is further arranged such that the main power switch includes a main live wire input port and a main neutral wire input port; the power output terminal includes a live wire output port and a neutral wire output port;

[0011] The main live wire input port and the main neutral wire input port are respectively connected to the live wire output port and the neutral wire output port through the first contact switch; one end of the first normally-open power switch is connected to the main live wire input port; the other end of the first normally-open power switch is sequentially connected to the main neutral wire input port through the second interlock switch and the first relay coil; the other end of the first normally-open power switch is sequentially connected to the main neutral wire input port through the first normally-open relay switch and the first contact coil;

[0012] The input end of the first power monitor is connected to the main live wire input port.

[0013] The utility model is further arranged such that one end of the second normally-open power switch is connected to the auxiliary power switch; the other end of the second normally-open power switch is sequentially connected to the auxiliary power switch through the first normally-closed relay switch, the second interlock switch and the second contact coil; the other end of the second normally-open power switch is sequentially connected to the auxiliary power switch through the second normally-open relay switch, the changeover switch and the second relay coil; the connection point between the first normally-closed relay switch and the second interlock switch is connected to the connection point between the second normally-open relay switch and the changeover switch.

[0014] The present utility model is further configured such that the secondary power switch includes a secondary live wire input port and a secondary neutral wire input port; the power output terminal includes a live wire output port and a neutral wire output port;

[0015] The secondary live wire input port and the secondary neutral wire input port are respectively connected to the live wire output port and the neutral wire output port through a second contact switch; one end of the second power normally open switch is connected to the secondary live wire input port; the other end of the second power normally open switch is sequentially connected to the secondary neutral wire input port through a first relay normally closed switch, a second interlock switch, and a second contact coil; the other end of the second power normally open switch is sequentially connected to the secondary neutral wire input port through a second relay normally open switch, a changeover switch, and a second relay coil;

[0016] The input end of the second power monitor is connected to the secondary live wire input port.

[0017] The present utility model is further configured such that the first relay is an intermediate relay.

[0018] The present utility model is further configured such that the second relay is a time relay.

[0019] The present utility model is further configured such that the changeover switch is a rocker switch.

[0020] The beneficial effect of the present utility model is that by providing a changeover switch and controlling the on / off of the changeover switch, both the self-switching and self-restoring function and the self-switching and non-self-restoring function can be achieved. Description of the Drawings

[0021] The utility model is further described with reference to the accompanying drawings. However, the embodiments in the drawings do not constitute any limitation to the present utility model. For those of ordinary skill in the art, other drawings can be obtained according to the following drawings without creative efforts.

[0022] Figure 1 is the circuit schematic diagram of the present utility model;

[0023] Wherein: 1, main power switch; 11, main live wire input port; 12, main neutral wire input port; 2, secondary power switch; 21, secondary live wire input port; 22, secondary neutral wire input port; 31, live wire output port; 32, neutral wire output port; 41, first power monitor; 42, first power normally open switch; 43, second power monitor; 44, second power normally open switch; 51, first contact coil; 52, first contact switch; 53, second contact coil; 54, second contact switch; 61, first relay coil; 62, first relay normally open switch; 63, first relay normally closed switch; 71, second relay coil; 72, second relay normally open switch; 81, first interlock switch; 82, second interlock switch; 9, changeover switch. Detailed implementation mode

[0024] The present invention will be further described in conjunction with the following embodiments.

[0025] As Figure 1 shown, a compatible dual - power switching circuit of this embodiment includes a main power switch 1, a secondary power switch 2, a first power monitor 41, a second power monitor 43, a first contactor, a second contactor, a first relay, a second relay, a switching switch 9, and a power output terminal; the first power monitor 41 is provided with a first normally - open power switch 42; the second power monitor 43 is provided with a second normally - open power switch 44; the first contactor is provided with a first contact coil 51 and a first contact switch 52; the second contactor is provided with a second contact coil 53 and a second contact switch 54; the first relay includes a first relay coil 61, a first normally - open relay switch 62, and a first normally - closed relay switch 63; the second relay includes a second relay coil 71 and a second normally - open relay switch 72; it also includes a first interlock switch 81 cooperating with the first contact switch 52 and a second interlock switch 82 cooperating with the second contact switch 54; the main power switch 1 is connected to the power output terminal through the first contact switch 52; the secondary power switch 2 is connected to the power output terminal through the second contact switch 54; the input end of the first power monitor 41 is connected to the main power switch 1; the input end of the second power monitor 43 is connected to the secondary power switch 2; one end of the first normally - open power switch 42 is connected to the main power switch 1; the other end of the first normally - open power switch 42 is sequentially connected to the main power switch 1 through the second interlock switch 82 and the first relay coil 61; the other end of the first normally - open power switch 42 is sequentially connected to the main power switch 1 through the first normally - open relay switch 62 and the first contact coil 51; the first normally - closed relay switch 63, the first interlock switch 81, the second contact coil 53, the second relay coil 71, and the second normally - open relay switch 72 form a self - locking circuit; the switching switch 9 is used to control the on - off of the self - locking circuit; the self - locking circuit is connected to the secondary power switch 2 through the second normally - open power switch 44. For a compatible dual - power switching circuit of this embodiment, one end of the second normally - open power switch 44 is connected to the secondary power switch 2; the other end of the second normally - open power switch 44 is sequentially connected to the secondary power switch 2 through the first normally - closed relay switch 63, the first interlock switch 81, and the second contact coil 53; the other end of the second normally - open power switch 44 is sequentially connected to the secondary power switch 2 through the second normally - open relay switch 72, the switching switch 9, and the second relay coil 71; the connection point between the first normally - closed relay switch 63 and the first interlock switch 81 is connected to the connection point between the second normally - open relay switch 72 and the switching switch 9.

[0026] Specifically, for the compatible dual - power switching circuit in this embodiment, when using the automatic switching and reclosing function, first switch the change - over switch 9 to the open position, and then close the main - power switch 1 and the secondary - power switch 2 in sequence. At this time:

[0027] When both the main - path power supply and the backup - path power supply are normal: The first - power monitor 41 detects that the main - path power supply is in a normal state, and its first - power normally - open switch 42 is closed at this time. The first - relay coil 61 is energized, causing the first - relay normally - open switch 62 to close and the first - relay normally - closed switch 63 to open. At this time, the first - contact coil 51 is energized, the first - contact switch 52 is attracted and closed, and the second - contact coil 53 is not energized, and the second - contact switch 54 is not attracted and closed. At this time, the circuit is powered by the main - path power supply;

[0028] When an abnormal fault occurs in the main - path power supply (such as undervoltage, overvoltage, open - phase, phase - sequence error, etc.): The first - power monitor 41 detects that the main - path power supply is in an abnormal state, and its first - power normally - open switch 42 remains in the open state without any action at this time. The first - relay coil 61 is not energized, the first - relay normally - open switch 62 does not act, and the first - relay normally - closed switch 63 does not act. At this time, the first - contact coil 51 is not energized, the first - contact switch 52 is not attracted and closed, the second - contact coil 53 is energized, and the second - contact switch 54 is closed. At this time, the circuit is powered by the backup - path power supply;

[0029] When the abnormal fault of the main - path power supply is restored: The first - power monitor 41 detects that the main - path power supply has returned to a normal state, and its first - power normally - open switch 42 is closed at this time. The first - relay coil 61 is energized, causing the first - relay normally - open switch 62 to close and the first - relay normally - closed switch 63 to open. At this time, the first - contact coil 51 is energized, the first - contact switch 52 is attracted and closed, the second - contact coil 53 is not energized, and the second - contact switch 54 is not attracted and closed. At this time, the circuit is powered by the main - path power supply; At this time, the circuit resumes power supply from the main - path power supply;

[0030] The above power - switching logic is embodied as automatic switching and reclosing; that is, when the main and backup power supplies are supplying power, the main - path power supply is given priority. When an abnormality occurs in the main - path, it switches to the backup - path power supply, and when the main - path power supply returns to normal, it switches back to the main - path power supply again. Since the change - over switch 9 is always in the open state, this branch actually does not participate in the power - switching control.

[0031] When using the "automatic switching but non - reclosing" function, first switch the change - over switch 9 to the closed position, and then close the main - power switch 1 and the secondary - power switch 2 in sequence. At this time:

[0032] When both the main power supply and the backup power supply are normal: The first power monitor 41 detects that the main power supply is in a normal state, and its first power normally open switch 42 is closed at this time. The first relay coil 61 is energized, causing the first relay normally open switch 62 to close and the first relay normally closed switch 63 to open. At this time, the first contact coil 51 is energized, the first contact switch 52 is attracted, and the second contact coil 53 is not energized, and the second contact switch 54 is not attracted. At this time, the circuit is powered by the main power supply;

[0033] When an abnormal fault occurs in the main power supply (such as undervoltage, overvoltage, phase loss, phase error, etc.): The first power monitor 41 detects that the main power supply is in an abnormal state, and its first power normally open switch 42 remains in the open state without any action at this time. The first relay coil 61 is not energized, the first relay normally open switch 62 does not act, and the first relay normally closed switch 63 does not act. At this time, the first contact coil 51 is not energized, the first contact switch 52 is not attracted, the second contact coil 53 is energized, and the second contact switch 54 is attracted. At this time, the circuit is powered by the backup power supply;

[0034] At the same time, since the changeover switch 9 is closed, the second relay coil 71 is energized, and its corresponding second relay normally open switch 72 is closed. This causes the first relay normally closed switch 63, the first interlock switch 81, the second contact coil 53, the second relay coil 71, and the second relay normally open switch 72 to actually form a self-locking circuit;

[0035] When the abnormal fault of the main power supply is restored: The first power monitor 41 detects that the main power supply has returned to a normal state, and its first power normally open switch 42 is closed at this time. The first relay coil 61 is energized, causing the first relay normally open switch 62 to close and the first relay normally closed switch 63 to open. However, due to the existence of the self-locking circuit, the loop of the second contact coil 53 has been self-locked at this time because the second relay normally open switch 72 is in the closed state. That is, even if the main power supply returns to normal again, as long as the backup power supply is normal, its corresponding second contact coil 53 remains energized all the time, causing the second contact switch 54 to remain closed all the time. At the same time, due to the interlocking effect of the mechanical-electrical first interlock switch 81, the first contact switch 52 remains in the open state all the time, so that the loop of the first contact coil 51 is in an open circuit state. Therefore, the final result is that even if the main power supply returns to normal from the fault state, the circuit still continues to be powered by the backup power supply at this time;

[0036] The above power supply switching logic is self-switching and non-self-restoring: when the main and backup power supplies are both in operation, the main power supply is given priority. When the main power supply experiences an abnormality, the circuit switches to the backup power supply. When the main power supply returns to normal, the backup power supply continues to supply power, and the main power supply is not restored. When the demand is to switch back from the self-switching and non-self-restoring mode to the self-switching and self-restoring mode, it is only necessary to switch the switch 9 to the off position; at this time, the circuit switches back to the main power supply and the self-switching and self-restoring mode is resumed.

[0037] In a compatible dual-power switching circuit of this embodiment, both the main power switch 1 and the secondary power switch 2 are circuit breakers or disconnect switches. Such a setting makes the overall structure stable and reliable.

[0038] In a compatible dual-power switching circuit of this embodiment, the main power switch 1 includes a main live wire input port 11 and a main neutral wire input port 12; the power output terminal includes a live wire output port 31 and a neutral wire output port 32;

[0039] The main live wire input port 11 and the main neutral wire input port 12 are respectively connected to the live wire output port 31 and the neutral wire output port 32 through a first contact switch 52; one end of the first normally open power switch 42 is connected to the main live wire input port 11; the other end of the first normally open power switch 42 is sequentially connected to the main neutral wire input port 12 through a second interlock switch 82 and a first relay coil 61; the other end of the first normally open power switch 42 is sequentially connected to the main neutral wire input port 12 through a first normally open relay switch 62 and a first contact coil 51;

[0040] The input end of the first power monitor 41 is connected to the main live wire input port 11.

[0041] Specifically, through the above settings in this embodiment, the second interlock switch 82, the first relay coil 61, the first normally open relay switch 62, and the first contact coil 51 can form a loop between the main live wire input port 11 and the main neutral wire input port 12.

[0042] In a compatible dual-power switching circuit of this embodiment, the secondary power switch 2 includes a secondary live wire input port 21 and a secondary neutral wire input port 22; the power output terminal includes a live wire output port 31 and a neutral wire output port 32;

[0043] The auxiliary live wire input port 21 and the auxiliary neutral wire input port 22 are respectively connected to the live wire output port 31 and the neutral wire output port 32 after passing through the second contact switch 54; one end of the second power normally open switch 44 is connected to the auxiliary live wire input port 21; the other end of the second power normally open switch 44 is sequentially connected to the auxiliary neutral wire input port 22 after passing through the first relay normally closed switch 63, the first interlock switch 81 and the second contact coil 53; the other end of the second power normally open switch 44 is sequentially connected to the auxiliary neutral wire input port 22 after passing through the second relay normally open switch 72, the changeover switch 9 and the second relay coil 71;

[0044] The input end of the second power monitor 43 is connected to the auxiliary live wire input port 21.

[0045] Specifically, through the above settings, the first relay normally closed switch 63, the first interlock switch 81, the second contact coil 53, the second relay coil 71 and the second relay normally open switch 72 form a loop between the auxiliary live wire input port 21 and the auxiliary neutral wire input port 22.

[0046] In a compatible dual-power switching circuit of this embodiment, the first relay is an intermediate relay. When the first relay coil 61 is powered on, the corresponding switch can act immediately, and the coil suction action time is set to T0 as a fixed value, usually at the ms level.

[0047] In a compatible dual-power switching circuit of this embodiment, the second relay is a time relay. When the second relay coil 71 is powered on, the delay time T1 of the corresponding switch action can be freely set according to the actual engineering application requirements, usually set to be slightly greater than the suction action time T0 of the first relay, such as T1=(1.1 - 1.3)T0, usually at the ms level.

[0048] In a compatible dual-power switching circuit of this embodiment, the changeover switch 9 is a boat switch. Through the above settings, it is convenient for users to switch the changeover switch 9.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A compatible dual-power switching circuit, characterized in that: It includes a main power switch, a secondary power switch, a first power monitor, a second power monitor, a first contactor, a second contactor, a first relay, a second relay, a changeover switch, and a power output terminal; The first power monitor is provided with a first normally-open power switch; the second power monitor is provided with a second normally-open power switch; the first contactor is provided with a first contact coil and a first contact switch; the second contactor is provided with a second contact coil and a second contact switch; the first relay includes a first relay coil, a first normally-open relay switch, and a first normally-closed relay switch; the second relay includes a second relay coil and a second normally-open relay switch; It further includes a first interlock switch cooperating with the first contact switch and a second interlock switch cooperating with the second contact switch; The main power switch is connected to the power output terminal through the first contact switch; the secondary power switch is connected to the power output terminal through the second contact switch; the input end of the first power monitor is connected to the main power switch; the input end of the second power monitor is connected to the secondary power switch; one end of the first normally-open power switch is connected to the main power switch; the other end of the first normally-open power switch is sequentially connected to the main power switch through the second interlock switch and the first relay coil; the other end of the first normally-open power switch is sequentially connected to the main power switch through the first normally-open relay switch and the first contact coil; the first normally-closed relay switch, the first interlock switch, the second contact coil, the second relay coil, and the second normally-open relay switch form a self-locking circuit; the changeover switch is used to control the on / off of the self-locking circuit; the self-locking circuit is connected to the secondary power switch through the second normally-open power switch.

2. The compatible dual-power switching circuit according to claim 1, wherein: Both the main power switch and the secondary power switch are circuit breakers or disconnect switches.

3. The compatible dual-power switching circuit according to claim 1, characterized in that: The main power switch includes a main live wire input port and a main neutral wire input port; the power output terminal includes a live wire output port and a neutral wire output port; The main live wire input port and the main neutral wire input port are respectively connected to the live wire output port and the neutral wire output port through the first contact switch; one end of the first normally-open power switch is connected to the main live wire input port; the other end of the first normally-open power switch is sequentially connected to the main neutral wire input port through the second interlock switch and the first relay coil; the other end of the first normally-open power switch is sequentially connected to the main neutral wire input port through the first normally-open relay switch and the first contact coil; The input end of the first power monitor is connected to the main live wire input port.

4. A compatible dual-power switching circuit according to claim 1, characterized in that: One end of the second normally-open power switch is connected to the secondary power switch; the other end of the second normally-open power switch is sequentially connected to the secondary power switch through the first normally-closed relay switch, the second interlock switch, and the second contact coil; the other end of the second normally-open power switch is sequentially connected to the secondary power switch through the second normally-open relay switch, the changeover switch, and the second relay coil; the connection point between the first normally-closed relay switch and the second interlock switch is connected to the connection point between the second normally-open relay switch and the changeover switch.

5. A compatible dual power supply switching circuit according to claim 4, characterized in that: The secondary power switch includes a secondary live wire input port and a secondary neutral wire input port; The power output terminal includes a live wire output port and a neutral wire output port; The auxiliary live wire input port and the auxiliary neutral wire input port are respectively connected to the live wire output port and the neutral wire output port after passing through the second contact switch; one end of the second normally open power switch is connected to the auxiliary live wire input port; the other end of the second normally open power switch is sequentially connected to the auxiliary neutral wire input port through the first normally closed relay switch, the second interlock switch and the second contact coil; the other end of the second normally open power switch is sequentially connected to the auxiliary neutral wire input port through the second normally open relay switch, the changeover switch and the second relay coil; The input end of the second power monitor is connected to the auxiliary live wire input port.

6. The compatible dual-power switching circuit according to claim 1, wherein: The first relay is an intermediate relay.

7. A compatible dual-power switching circuit according to claim 1, characterized in that: The second relay is a time relay.

8. A compatible dual-power switching circuit according to claim 1, characterized in that: The changeover switch is a rocker switch.

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