Automatic switching device for energy storage system

Abstract

The utility model discloses an automatic switching device for an energy storage system, which comprises a main power supply, a standby power supply, a main power supply control loop and a standby power supply control loop. A coil of the main supply contactor is connected in series with a normally open contact of the first relay and then is connected in parallel with a coil of the first relay; the standby power supply control loop comprises a first branch and a second branch, the first branch is connected with a coil of a second relay, a normally closed contact of the main power supply contactor and a normally closed contact of the first relay in series, the second branch is connected with a normally open contact of the second relay and a coil of the standby power supply contactor in series, and the first branch is connected with the second branch in parallel. According to the utility model, the automatic switching and automatic recovery functions of the circuit are realized through a relay combination mode, the device is more economical than an integrated dual-power conversion device, more flexible configuration and adjustment are allowed, and the type, contact configuration and control logic of the relay can be adjusted according to specific requirements so as to adapt to different application scenes.

Description

Technical Field

[0001] The utility model relates to the field of circuit control, in particular to an automatic switching device for an energy storage system. Background Art

[0002] In energy storage systems, ensuring the continuity and reliability of power supply is crucial. Therefore, existing energy storage system containers are typically equipped with an auxiliary power supply, which allows for seamless switching to a backup power source in the event of a main power failure, thereby maintaining stable system operation. This dual power supply system typically employs a dual power supply system, one primary and one backup. The primary power supply is typically taken from the AC side of the energy storage bidirectional converter (PCS), while the backup power supply is taken from the station transformer cabinet. To achieve automatic conversion between these two modes, an integrated dual power conversion device is typically used. This device operates in an automatic switching and recovery mode. That is, when the main power supply fails, the conversion device automatically switches to the backup power circuit, using the station transformer for power supply; when the main power supply is restored, the conversion device automatically switches back to the main power supply circuit for power supply.

[0003] While this dual power conversion circuit for the auxiliary power supply can provide a backup power circuit, ensuring continued power supply in the event of a main power failure, the cost of an integrated dual power transfer switch is relatively high. Therefore, existing technologies typically use relays to create a dual power supply, thereby achieving the function of an integrated dual power transfer switch.

[0004] Although this method can also achieve the function of dual power conversion, its structure is often more complicated, which increases the difficulty of circuit installation and maintenance. Utility Model Content

[0005] The utility model provides an automatic switching device for an energy storage system, which realizes the functions of automatic switching and automatic recovery of a circuit by adopting a relay combination. The structure is simpler and the installation and maintenance of the circuit are easy.

[0006] To achieve the above-mentioned objectives, the present invention provides an automatic switching device for an energy storage system, comprising: a main power supply, a backup power supply, a main power supply control circuit and a backup power supply control circuit; the main power supply control circuit comprises a main supply contactor and a first relay, the coil of the main supply contactor being connected in series with the normally open contact of the first relay and then connected in parallel with the coil of the first relay; the backup power supply control circuit comprises a first branch and a second branch connected in parallel with each other, the first branch comprising the coil of the second relay arranged in series, the normally closed contact of the main supply contactor and the normally closed contact of the first relay, and the second branch comprising the normally open contact of the second relay and the coil of the backup contactor arranged in series.

[0007] Preferably, the main power supply control circuit includes a third branch and a fourth branch connected in parallel with each other, and is provided with a switching switch connected in series with the first relay, the switching switch includes a first normally closed contact, a first normally open contact, a second normally open contact and a second normally closed contact, the backup supply contactor also includes a normally closed contact, the third branch includes a first normally closed contact and a first normally open contact connected in series, and the fourth branch includes a second normally open contact, a second normally closed contact and a normally closed contact of the backup supply contactor connected in series.

[0008] Preferably, a first fuse is further provided in the main power supply control circuit, and a second fuse is further provided in the backup power supply control circuit.

[0009] Preferably, the first relay and the second relay are both time relays.

[0010] The benefits of the present invention include at least the following: the present invention realizes the self-closing and self-restoring functions of the circuit by means of a relay combination, which is more economical than an integrated dual power conversion device; at the same time, the relay combination allows for more flexible configuration and adjustment, and the type of relay, contact configuration and control logic can be adjusted according to specific needs to adapt to different application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A circuit diagram of an embodiment of the present utility model;

[0012] Figure 2 This is a structural diagram of a main supply contactor according to an embodiment of the present utility model;

[0013] Figure 3 This is a schematic structural diagram of a first relay according to an embodiment of the present utility model;

[0014] Figure 4 This is a schematic structural diagram of a second relay according to an embodiment of the present utility model;

[0015] Figure 5 This is a structural diagram of a backup contactor according to an embodiment of the present utility model.

[0016] In the figure: 1-main power supply; 2-backup power supply; 3-main power supply control circuit; 4-backup power supply control circuit; 5-main supply contactor; 51-main supply contactor coil; 52-main supply contactor normally closed contact; 6-first relay; 61-first relay coil; 62-first relay normally open contact; 63-first relay normally closed contact; 7-second relay; 71-second relay coil; 72-second relay normally open contact; 8-backup contactor; 81-backup contactor coil; 82-backup contactor normally closed contact; 9-transfer switch; 91-first normally closed contact of transfer switch; 92-first normally open contact of transfer switch; 93-second normally open contact of transfer switch; 94-second normally closed contact of transfer switch; 10-first fuse; 11-second fuse DETAILED DESCRIPTION

[0017] The following is a clear and complete description of the technical solutions in the embodiments of the present invention, in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of protection of the present invention.

[0018] like Figure 1 As shown, the present invention provides an automatic switching device for an energy storage system, comprising a main power supply 1, a backup power supply 2, a main power supply control circuit 3 and a backup power supply control circuit 4. The main power supply control circuit 3 comprises a main supply contactor 5 and a first relay 6, as shown in FIG. Figure 2 As shown, the main supply contactor 5 includes a coil 51 and a normally closed contact 52. Figure 3 As shown, the first relay 6 includes a coil 61, a normally open contact 62 and a normally closed contact 63. The coil 51 of the main supply contactor 5 is connected in series with the normally open contact 62 of the first relay 6 and then connected in parallel with the coil 61 of the first relay 6. The backup power supply control circuit 4 includes a first branch, a second branch, a second relay 7 and a backup contactor 8 connected in parallel. Figure 4 As shown, the second relay 7 includes a coil 71 and a normally open contact 72. Figure 5 As shown, the backup contactor 8 includes a coil 81 and a normally closed contact 82, the first branch includes the coil 71 of the second relay 7, the normally closed contact 52 of the main supply contactor 5 and the normally closed contact 63 of the first relay 6 arranged in series, and the second branch includes the normally open contact 72 of the second relay 7 and the coil 81 of the backup contactor 8 arranged in series.

[0019] When the main power circuit is energized, coil 61 of first relay 6 in main power supply control circuit 3 is energized and closed. At this time, normally closed contact 63 of first relay 6 in backup power supply control circuit 4 momentarily actuates, changing from closed to open, causing coil 71 of second relay 7 to lock and prevent it from closing. Normally open contact 62 of first relay 6 closes, energizing coil 51 of main supply contactor 5, connecting the load and now supplying power to main power supply 1.

[0020] When the backup power supply 2 is powered and the main power supply 1 is powered off, the coil 61 of the first relay 6 in the main power supply control circuit 3 loses power, the normally open contact 62 of the first relay 6 acts instantaneously, and the closed point becomes an open point, and the coil 51 of the main supply contactor 5 loses power. At this time, the normally closed contact 52 of the main supply contactor 5 and the normally closed contact 63 of the first relay 6 in the backup power supply control circuit 4 act instantaneously, and the open point becomes a closed point, the coil 71 of the second relay 7 is energized and attracted, the normally open contact 72 of the second relay 7 is closed, the coil 81 of the backup contactor 8 is energized and attracted, and the load is connected. At this time, the backup power supply 2 supplies power.

[0021] When the backup power supply 2 is supplying power, if the voltage of the main supply circuit is restored, the coil 61 of the first relay 6 in the main supply circuit is energized and attracted, the normally closed contact 63 of the first relay 6 in the backup supply circuit is disconnected, the coil 71 of the second relay 7 in the backup supply circuit loses power, the normally closed contact 73 of the second relay 7 is instantaneously actuated, the closed point becomes the open point, the coil 81 of the backup contactor 8 loses power, and the backup power supply 2 is disconnected. At this time, the normally open contact 62 of the first relay 6 in the main supply circuit is closed, the coil 51 of the main supply contactor 5 is energized and attracted, the normally closed contact 52 of the main supply contactor 5 is closed, the load is connected, and the main power supply 1 is now supplying power.

[0022] The utility model can realize the self-closing and self-restoring functions of the circuit by means of a relay combination. Compared with the existing dual power transfer switch, the relay combination method is more flexible to use and has lower procurement and maintenance costs.

[0023] Specifically, the main power supply control circuit 3 of the embodiment of the present invention includes a third branch and a fourth branch connected in parallel, and is provided with a transfer switch 9 connected in series with the first relay 6. The transfer switch 9 includes a first normally closed contact 91, a first normally open contact 92, a second normally open contact 93, and a second normally closed contact 94. The third branch includes the first normally closed contact 91 and the first normally open contact 92 connected in series, and the fourth branch includes the second normally open contact 93, the second normally closed contact 94, and the normally closed contact 82 of the backup contactor 8 connected in series.

[0024] The transfer switch 9 is a double-pole double-throw switch, wherein the first pole includes a first normally closed contact 91 and a second normally open contact 93 , and the second pole includes a first normally open contact 92 and a second normally closed contact 94 .

[0025] When the circuit switches to the automatic resetting mode, the first normally closed contact 91 is closed, the first normally open contact 92 is closed, the second normally open contact 93 is opened, and the second normally closed contact 94 is opened, and the automatic resetting function is realized by the method in Example 1.

[0026] When the circuit switches to the automatic-return, non-automatic-reset mode, first normally closed contact 91 opens, first normally open contact 92 opens, second normally open contact 93 closes, and second normally closed contact 94 closes. With backup power supply 2 supplying power, the main supply circuit voltage is restored. Because coil 81 of backup contactor 8 in the backup circuit remains energized, normally closed contact 82 of backup contactor 8 in the main supply circuit remains open, blocking coil 61 of first relay 6. Main contactor 5 cannot be closed, and main power supply 1 is unable to supply power, achieving the non-automatic-reset function.

[0027] Compared with the existing dual power transfer switch solution, the relay combination method can select the switching mode of automatic switching with automatic recovery or automatic switching without automatic recovery, which is more flexible to use and has lower procurement and maintenance costs.

[0028] Specifically, a first fuse 10 is provided in the main power supply control circuit 3 , and a second fuse 11 is provided in the backup power supply control circuit 4 .

[0029] Fuses can provide overload protection for the power control circuit to prevent damage to equipment due to excessive current.

[0030] Specifically, the first relay 6 and the second relay 7 are time relays.

[0031] The normally open contacts of the first relay 6 and the second relay 7 correspond to the delayed closing contacts of the time relay, while the normally closed contacts correspond to the delayed opening contacts of the time relay. The time relays delay the switching of the main power supply 1 and the backup power supply 2, helping to prevent damage to the load or power system caused by excessive power switching. The delay time of the two time relays can be adjusted between 0 and 60 seconds.

[0032] The technical features of the above embodiments may be combined in any manner. To simplify the description, not all possible combinations of the technical features in the above embodiments are described. Only preferred embodiments of the present invention are presented. While the description is relatively specific and detailed, it should not be construed as limiting the scope of the present invention. As long as there are no contradictions in the combination of these technical features, they should be considered to be within the scope of this specification.

[0033] It should be noted that those skilled in the art may make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present utility model patent shall be based on the appended claims.

Claims

1. An automatic switching device for an energy storage system, characterized in that: include: A main power supply (1), a backup power supply (2), a main power supply control circuit (3) and a backup power supply control circuit (4); the main power supply control circuit (3) includes a main supply contactor (5) and a first relay (6), the coil (51) of the main supply contactor (5) and the normally open contact (62) of the first relay (6) are connected in series and then connected in parallel with the coil (61) of the first relay (6); the backup power supply control circuit (4) includes a first branch and a second branch connected in parallel with each other, the first branch includes a coil (71) of a second relay (7) arranged in series, a normally closed contact (52) of the main supply contactor (5) and a normally closed contact (63) of the first relay (6), and the second branch includes a normally open contact (72) of the second relay (7) and a coil (81) of the backup contactor (8) arranged in series.

2. The automatic switching device for an energy storage system according to claim 1, characterized in that: The main power supply control circuit (3) includes a third branch and a fourth branch connected in parallel with each other, and is provided with a transfer switch (9) connected in series with the first relay (6), the transfer switch (9) including a first normally closed contact (91), a first normally open contact (92), a second normally open contact (93) and a second normally closed contact (94), the standby contactor (8) also includes a normally closed contact (82), the third branch includes the first normally closed contact (91) and the first normally open contact (92) connected in series, and the fourth branch includes the second normally open contact (93), the second normally closed contact (94) and the normally closed contact (82) of the standby contactor (8) connected in series.

3. The automatic switching device for an energy storage system according to claim 1, characterized in that: A first fuse (10) is provided in the main power supply control circuit (3), and a second fuse (11) is provided in the backup power supply control circuit (4).

4. The automatic switching device for an energy storage system according to claim 1, characterized in that: The first relay (6) and the second relay (7) are time relays.

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