Low-voltage power distribution anti-misoperation device and method

Abstract

The invention discloses a low-voltage power distribution anti-misoperation device which comprises an anti-reverse power transmission module, an anti-misoperation module, a power regulation anti-misoperation auxiliary module, an interaction control screen and a state logic switching module. The invention discloses a low-voltage power distribution anti-misoperation method and device, and the method and device can effectively eliminate the above problems through an anti-reverse power transmission module, an anti-misoperation module and a power adjustment anti-misoperation auxiliary module, have the functions of preventing reverse power transmission and preventing power failure of a user caused by manual operation, and have a locking function when a line does not meet a loop closing condition. On the basis that an original secondary loop is provided with three locks and two keys, three heat reverse connection points are added, the device keeps the original three-lock and two-key protection function of a power supply company, and the intelligent heat reverse loop closing operation function is achieved. Therefore, the five-prevention function under the condition that the electric operation cannot be realized due to the defects of the device or the electrical secondary circuit can be met.

Description

Technical Field

[0001] The present invention relates to the technical field, and in particular to a low-voltage power distribution misoperation prevention device and method. Background Art

[0002] A distribution room refers to an indoor distribution site with low-voltage loads. It mainly distributes electricity to low-voltage users and is equipped with medium-voltage incoming lines (a small number of outgoing lines may be provided), distribution transformers, and low-voltage distribution devices. Facilities for equipment with voltage levels of 10kV and below are divided into high-voltage distribution rooms and low-voltage distribution rooms. High-voltage distribution rooms generally refer to 6kV-10kV high-voltage switch rooms; low-voltage distribution rooms generally refer to 400V distribution rooms with 20kV or 35kV station transformer outgoing lines.

[0003] Generally, the anti-error measures for switching operation in the power distribution room adopt the electrical and mechanical "three locks and two keys" method. Such anti-error measures can play a role in ensuring personal safety and equipment safety, but this anti-error method has certain defects;

[0004] (1) During the switching operation, the user will experience a short power outage, which will lead to a poor user experience;

[0005] (2) In addition, the power grid company requires that the power distribution room power adjustment operation adopt hot switching operation from the perspective of quality service, which can improve the user's power consumption experience. However, due to the uneven skill levels of operators, manual hot switching operation has great risks, and there is a lack of risk warnings or alarms during the switching process, which poses a safety hazard.

[0006] The main risks of manual switching operations are:

[0007] When new equipment is put into operation or high-voltage line maintenance is completed, when switching operation is required to supply power, there may be improper human operation, resulting in the risk of reverse power supply;

[0008] During the maintenance of distribution lines or transformers, when manual opening and closing of switches is required to transfer power, there may be human operation logic errors, resulting in short-term power outages for users;

[0009] During daily power switching operations, it is necessary to check the line voltage difference, check whether the user load current exceeds the transformer capacity, etc., to determine whether the current state meets the conditions for closing the loop and switching. This process requires technical calculations. If there are manual calculation errors, closing the loop will cause equipment damage or switch tripping accidents;

[0010] When performing manual heat-reversal operations, a circulation shock will be formed, and long-term circulation is likely to cause equipment damage;

[0011] When the manual cold-down operation is performed, the busbar loses power within seconds or minutes, resulting in poor user experience.

[0012] And the main risks and warnings in the operation process are as follows:

[0013] Low-voltage incoming power supply loss-of-power warning;

[0014] Low-voltage busbar loss-of-power warning;

[0015] Overload warning will occur during transfer power supply;

[0016] Warning for the voltage difference between two incoming power supplies exceeding the set value;

[0017] Warning for excessive phase angle difference of the incoming power supply;

[0018] Warning for the power supply risk existing in the manual switching operation selection mode;

[0019] Therefore, we propose a low-voltage distribution anti-misoperation device and method. Summary of the Invention

[0020] The purpose of the present invention is to provide a low-voltage distribution anti-misoperation device and method to solve the problem of operation errors during manual hot transfer operation in the background technology, which may lead to safety accidents or power outage events.

[0021] To achieve the above object, the present invention provides the following technical solution: A low-voltage distribution anti-misoperation device, the low-voltage distribution anti-misoperation device includes:

[0022] Anti-backfeed power module: When the anti-backfeed power module detects that one of the two independent incoming lines loses power and the incoming line switch is in the closed state, the anti-backfeed power module prevents non-compliant loop closing operation;

[0023] Anti-misoperation module: The anti-misoperation module is used to detect whether the line meets the loop closing condition. When the line does not meet the loop closing condition, the locking function is started and the loop closing button fails;

[0024] Power transfer anti-misoperation auxiliary module: The power transfer anti-misoperation auxiliary module is used to realize intelligent hot transfer loop closing operation and avoid power outage operation;

[0025] Interactive control screen: The interactive screen is used for intelligent power distribution operation and issues error alarms;

[0026] State switching logic module: The state switching logic module completes the switching operation by controlling the target state of the switch, and judges whether the state switching conforms to hot transfer operation or cold transfer operation. When there is a risk of user power loss in the switching state selected by the staff, the interactive control screen will issue an error warning and stop the operation.

[0027] The anti-misoperation measures for general switchgear operation in power distribution rooms adopt the electrical and mechanical "three locks and two keys" method. Such anti-misoperation measures can play a role in ensuring personal safety and equipment safety. However, there are certain defects in this anti-misoperation method; it will cause short-term power outages for users during switchgear operation, resulting in poor user experience; and from the perspective of providing high-quality services, the power grid company requires that the power adjustment operation in the power distribution room adopt hot switching operation, which can improve the user's power consumption experience. However, due to the uneven skill levels of operators, there are significant potential risks in manual hot switching operation, and there is a lack of risk prompts or warnings during the switchgear operation process, posing safety hazards; The present invention discloses a low-voltage power distribution anti-misoperation method and device, aiming to solve the problem of operation errors during manual hot switching operation and prevent possible safety accidents or power outage events. And the anti-backfeeding power module, anti-misoperation module, and power adjustment anti-misoperation auxiliary module set therein can effectively eliminate the above problems, having the functions of preventing backfeeding power, preventing user power outages caused by manual operations, and locking the function when the line does not meet the loop closing condition, thereby prohibiting non-compliant loop closing operations; Moreover, when the device detects that one of the two independent incoming lines loses power and the incoming line switch is in the closed state, the device uses the locking logic, and the 3 built-in relays are disconnected to lock the loop closing function of the secondary circuit of the electric operator. At this time, if the operator manually presses the loop closing operation of the electric operator circuit, the closing operation will not be executed; If the staff performs a power transfer operation through the interactive interface of the device at this time, the device will first trip the low-voltage switch of the power-loss line and then close other switches, effectively preventing backfeeding power events. Secondly, the built-in protection logic of this device can detect the line status in real time, judge the power outage risk, give a prompt for operations with power outage risks, and terminate the execution, greatly improving the power supply reliability of users. And this device retains the original "three locks and two keys" protection function of the power supply company unchanged and realizes the intelligent hot switching loop closing operation function. On the basis of the original secondary circuit (with three locks and two keys), three additional hot switching contacts are added to meet the five-prevention function when the device or the electrical secondary circuit has defects and cannot achieve electric operation; During the hot switching operation, the three hot switching contacts are closed, and after the hot switching ends, the three hot switching contacts are separated, that is, the original loop three locks and two keys anti-misoperation function is retained, and the hot switching operation is realized, providing users with a power consumption experience without power outages.

[0028] As a further description of the above technical solution:

[0029] The switches are set in three groups and are arranged at the two incoming line power sources and between the power sources on the bus side of the two incoming line switches.

[0030] As a further description of the above technical solution:

[0031] The anti-backfeed power module further includes a latching logic module. The latching logic module has an in-built relay, and the anti-backfeed power module uses the latching logic to disconnect the in-built relay. The latching logic module prohibits the simultaneous closing of three switches to prevent backfeed power caused by improper closing.

[0032] As a further description of the above technical solution:

[0033] It further includes three thermal inversion contacts, which are added to the secondary circuit of the power distribution system. During the thermal inversion operation, the three thermal inversion contacts are closed, and when the thermal inversion ends, the three thermal inversion contacts are separated.

[0034] As a further description of the above technical solution:

[0035] A low-voltage power distribution anti-misoperation method, which includes an anti-backfeed power method and a normal power adjustment anti-misoperation auxiliary operation method.

[0036] As a further description of the above technical solution:

[0037] The anti-backfeed power method includes the following steps:

[0038] Step A1: When the low-voltage power distribution anti-misoperation device detects the loss of power of any incoming power supply, it triggers the internal "three locks and two keys" latching logic, prohibits the simultaneous closing of 3 switches, and continuously detects the switch status;

[0039] Step A2: When it is detected that 2 switches are in the closed position and 1 switch is in the open position, the switch in the open position is latched. When it is detected that 1 switch is in the closed position and 2 switches are in the open position, the latching function is not executed;

[0040] Step A3: After the switch anti-backfeed power is latched, the unlocking method is that for two switches in the closed position, one of the switches is opened, and the latching is automatically released.

[0041] As a further description of the above technical solution:

[0042] The normal power adjustment anti-misoperation auxiliary operation method includes the following steps:

[0043] Step B1: Add three thermal inversion contacts to the secondary circuit. During the thermal inversion operation, the three thermal inversion contacts are closed. When the thermal inversion ends, the three thermal inversion contacts are separated, and at the same time, the "three locks and two keys" anti-misoperation function of the secondary circuit is retained.

[0044] Step B2: During normal power adjustment, when both incoming power supplies have voltage and two switches are in the closed position, the device performs normal power adjustment anti-misoperation auxiliary operation, otherwise it is regarded as an abnormal state;

[0045] Step B3: State switching logic is switched. The staff selects the target state of the switch through the interactive control screen to complete the switching operation. The switching operation state is presented in a graphical form. When it is judged that there is a risk of power outage for the user in the switching state selected by the staff, an error warning is issued and the operation is stopped.

[0046] As a further description of the above technical solution:

[0047] The implementation method for judging whether there is a risk in the switching state includes the following steps:

[0048] Step S1: First, determine whether "hot switching operation" is allowed. If hot switching is not allowed, then perform "cold switching operation";

[0049] Step S2: Then calculate whether the load after switching exceeds the transformer capacity. If it is detected that the load after transfer exceeds the transformer capacity, the operation is terminated and a voice prompt is given using the interactive control screen; when the transformer capacity allows, the interactive control screen gives a voice prompt to perform cold switching operation or hot switching operation.

[0050] As a further description of the above technical solution:

[0051] The detection period for real-time detection of the switch state is once every 0.5S.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] 1. The present invention discloses a low-voltage power distribution anti-misoperation method and device, aiming to solve the problem of operation errors during manual hot switching operation, and to solve possible safety accidents or power outage events. And the anti-backfeeding power module, anti-misoperation module, and power adjustment anti-misoperation auxiliary module set therein can effectively eliminate the above problems, and have the functions of preventing backfeeding power, preventing user power outage caused by manual operation, and locking the function when the line does not meet the loop closing condition, thereby prohibiting non-compliant loop closing operations;

[0054] 2. Moreover, when the device detects that one of the two independent incoming lines loses power and the incoming line switch is in the closed state, the device uses the locking logic, and the 3 built-in relays are disconnected to lock the loop closing function of the electric operation secondary circuit. At this time, if the operator manually presses the loop closing operation of the electric operation circuit, the closing will not be executed; if the operator performs a power transfer operation through the interactive interface of the device at this time, the device will first trip the low-voltage switch of the power-outage line and then close other switches, effectively preventing the occurrence of backfeeding power events;

[0055] 3. Secondly, the built-in protection logic of the present device can real-time detect the line state, judge the power outage risk, give a prompt for the operation with power outage risk, and terminate the execution, greatly improving the power supply reliability of the user.

[0056] 4. Moreover, the device retains the original "three locks and two keys" protection function of the power supply company unchanged and realizes the intelligent hot loop closing operation function. Based on the original secondary circuit (with three locks and two keys), three additional hot connection points are added to meet the five-prevention function in case of defects in the device or the electrical secondary circuit that prevent electric operation. During the hot loop closing operation, the three hot connection points are closed, and after the hot loop closing is completed, the three hot connection points are separated, thus retaining the original three-locks-and-two-keys anti-misoperation function of the circuit and realizing the hot loop closing operation, providing the user with a power supply experience without power interruption.

[0057] 5. Finally, the device can effectively prevent loop closing operations when the loop closing conditions are not met. When the loop closing conditions are not satisfied, the device uses the built-in relay to lock the loop closing function, rendering the loop closing function of the electric operation circuit ineffective. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 is a flowchart of the anti-backfeeding state switching logic method of the present invention;

[0059] Figure 2 is a schematic diagram of the comparison circuit of the secondary circuit of the present invention before and after transformation;

[0060] Figure 3 is a schematic diagram of the control state conversion and operation state switching I of the present invention;

[0061] Figure 4 is a schematic diagram of the control state conversion and operation state switching II of the present invention;

[0062] Figure 5 is a schematic diagram of the control state conversion and operation state switching III of the present invention;

[0063] Figure 6 is a schematic diagram of the control state conversion and operation state switching IV of the present invention;

[0064] Figure 7 is a schematic diagram of the control state conversion and operation state switching V of the present invention;

[0065] Figure 8 is a schematic diagram of the control state conversion and operation state switching VI of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0066] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0067] Embodiment 1:

[0068] Please refer to Figure 1-2 , the present invention provides a technical solution: a low-voltage power distribution anti-misoperation device, and the low-voltage power distribution anti-misoperation device includes:

[0069] Anti-backfeed power module: When the anti-backfeed power module detects that one of the two independent incoming lines loses power and the incoming line switch is in the closed state, the anti-backfeed power module prevents non-compliant loop closing operations. In addition, the staff can perform correct power transfer operations through the interactive interface, thus effectively preventing the occurrence of backfeed power;

[0070] Anti-misoperation module: The anti-misoperation module is used to detect whether the line meets the loop closing conditions, and activates the locking function when the line does not meet the loop closing conditions;

[0071] Among them, before the loop closing operation is performed, a pressure difference threshold is set, and when the loop closing conditions exceed the pressure difference threshold, the loop closing button fails, ensuring that the loop closing operation is only allowed under safe conditions. When the loop closing conditions are not met, the device uses the built-in relay to lock the loop closing function, making the loop closing function of the electric operation circuit fail. Assuming that the loop closing pressure difference threshold is 12V, when the pressure difference between the two incoming lines detected by the device is 13V, that is, the actual pressure difference exceeds the permitted pressure difference for loop closing, the loop closing operation is not in compliance. At this time, the device will activate the locking function, making the loop closing button of the electric operation secondary circuit fail;

[0072] Power transfer anti-misoperation auxiliary module: The power transfer anti-misoperation auxiliary module is used to realize intelligent hot transfer loop closing operation and avoid power outage operations;

[0073] Among them, it also includes three sets of hot transfer contacts, and the hot transfer contacts are added to the secondary circuit of the power distribution system. During the hot transfer operation, the three sets of hot transfer contacts are closed, and at the end of the hot transfer, the three sets of hot transfer contacts are separated. That is, it retains the anti-misoperation function of three locks and two keys in the original circuit, and realizes the hot transfer operation, providing the user with a power consumption experience without power outage. The above transformation not only retains the original "three locks and two keys" protection function of the power supply company unchanged, but also realizes the intelligent hot transfer loop closing operation function. The implementation method is to develop a new device, and on the basis of the original secondary circuit (with three locks and two keys), add three sets of hot transfer contacts to meet the five-prevention function in the case where the device or the electrical secondary circuit has defects and cannot realize electric operation;

[0074] During the hot transfer operation, the three sets of hot transfer contacts are closed, and at the end of the hot transfer, the three sets of hot transfer contacts are separated. That is, it retains the anti-misoperation function of three locks and two keys in the original circuit, and realizes the hot transfer operation, providing the user with a power consumption experience without power outage; During normal power transfer, when both incoming line power supplies are energized and two switches are in the closed position, the device performs normal power transfer anti-misoperation auxiliary operations, otherwise it is regarded as an abnormal state.

[0075] Interactive control screen: The interactive screen is used for intelligent power distribution operations and issues error alarms;

[0076] Among them, for the set interactive control screen, the staff only need to select the target state of the switch through the options on the interactive control screen, and the device can complete the automatic switching operation. All states are presented in a graphical form, which is intuitive and easy to understand.

[0077] State switching logic module: The state switching logic module completes the switching operation by controlling the target state of the switch and determines whether the state switching conforms to the hot switching operation or the cold switching operation. Among them, the hot switching operation: refers to switching a running circuit or load from one power source to another without interrupting the power supply. This operation is usually used to ensure continuous power supply to users, especially during equipment maintenance, upgrade or fault handling. For example, in a substation, seamless switching between two power sources can be achieved by closing the circuit breaker of the standby power source while keeping the circuit breaker of the original power source closed. The advantage of doing this is that it can avoid the impact of power outage on users, but strict operating procedures and technical guarantees are required to ensure safety; the cold switching operation: is a switching operation carried out under the condition of cutting off the power supply. This means that before performing the cold switching, the power supply to the relevant circuit or equipment must be stopped first. This method is often used in situations where the hot switching operation cannot be implemented, such as when the system does not allow multiple parallel paths or there is a risk of reverse power feeding. Although the cold switching will cause a short-term power outage, it is sometimes a safer choice, especially when dealing with complex faults or large-scale system transformations. When there is a risk of power loss for users in the switching state selected by the staff, an error warning will be issued and the operation will be stopped. The implementation method is as follows. First, the device determines whether the "hot switching operation" is allowed. If the hot switching is not allowed, the "cold switching operation" will be performed. Then, it calculates whether the load after switching exceeds the transformer capacity. If the device detects that the load after transfer will exceed the transformer capacity, the operation will be terminated and a voice prompt will be given; if the transformer capacity allows, the device will perform the (cold switching or hot switching) operation through a voice prompt.

[0078] Please refer to Figures 1-8 , the following are multiple control state conversion operation methods. In the following multiple state switching diagrams, the left state is the current state and the right side is the target state that needs to be adjusted:

[0079] State switching one:

[0080]

[0081] State switching two

[0082] State switching three

[0083] State switching four

[0084]

[0085] State Switch Five

[0086]

[0087] State Switch Six

[0088]

[0089] When there is a failure in the switch trip or a remote signal detection error for the above operations, the device will execute the anti-misoperation fallback logic, restore the switch state before the operation, and give an alarm voice prompt using the interactive control screen;

[0090] If the switch has a voltage loss coil, when one incoming line loses power and trips, only one of the three switches on the low-voltage line is in the closed position. At this time, the device considers the line to be in an abnormal state and prohibits the use of the state switching method for switching operations. Only after manually checking the line and closing one switch manually, can the device use the operation assistance function after recognizing the normal operation mode.

[0091] The switch is set in three groups and is arranged at the two incoming line power supplies and between the power supplies on the bus side of the two incoming line switches.

[0092] The anti-backfeeding power module further includes a locking logic module. The locking logic module has an internal relay. The anti-backfeeding power module uses the locking logic to disconnect the internal relay. The locking logic module prohibits the three switches from closing simultaneously to ensure that when any incoming power supply loses power, the switch is automatically locked to prevent backfeeding power caused by improper closing.

[0093] Embodiment 2:

[0094] Please refer to Figure 1 and Figure 2 , a low-voltage power distribution anti-misoperation method, which includes an anti-backfeeding power method and a normal power adjustment anti-misoperation assistance method.

[0095] The anti-backfeeding power method includes the following steps:

[0096] Step A1: When the low-voltage power distribution anti-misoperation device detects that any incoming power supply loses power, it triggers the internal "three locks and two keys" locking logic, prohibits the three switches from closing simultaneously, and continuously detects the switch state;

[0097] Step A2: When it is detected that two switches are in the closed position and one switch is in the open position, lock the switch in the open position. When it is detected that one switch is in the closed position and two switches are in the open position, the locking function is not executed;

[0098] Step A3: After the switch is locked against back-feeding, the unlocking method is that for two switches in the closed position, one of the switches is tripped, and the locking is automatically released.

[0099] The normal power adjustment anti-misoperation auxiliary operation method includes the following steps:

[0100] Step B1: Add three sets of hot transfer contacts on the secondary circuit. During the hot transfer operation, the three sets of hot transfer contacts are closed. After the hot transfer ends, the three sets of hot transfer contacts are separated, and at the same time, the "three locks and two keys" anti-misoperation function of the secondary circuit is retained.

[0101] Among them, the transformation on the secondary circuit adds the transformation that not only retains the original "three locks and two keys" protection function of the power supply company unchanged, but also realizes the intelligent hot transfer and loop closing operation function. On the basis of the original secondary circuit (with three locks and two keys), three sets of hot transfer contacts are added to meet the five-prevention function in the case where the device or the electrical secondary circuit has defects and cannot realize the electric operation.

[0102] Step B2: During normal power adjustment, when both incoming power supplies have voltage and two switches are in the closed position, the device performs normal power adjustment anti-misoperation auxiliary operation, otherwise it is regarded as an abnormal state.

[0103] Step B3: The staff selects the target state of the switch through the interactive control screen to complete the switching operation. The switching operation state is presented in a graphical form, which is intuitive and easy to understand. When it is judged that there is a risk of power loss for the switching state selected by the staff, an error warning is issued and the operation is stopped.

[0104] The implementation method for judging whether there is a risk in the switching state includes the following steps:

[0105] Step S1: First, determine whether "hot transfer operation" is allowed. If hot transfer is not allowed, "cold transfer operation" is performed.

[0106] Step S2: Then calculate whether the load after switching exceeds the transformer capacity. If it is detected that the load after transfer exceeds the transformer capacity, the operation is terminated, and a voice prompt is given using the interactive control screen; when the transformer capacity allows, the interactive control screen gives a voice prompt to perform cold transfer operation or hot transfer operation.

[0107] The detection period for real-time detection of the switch state is once every 0.5S.

[0108] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low-voltage power distribution anti-misoperation device, characterized in that: The low-voltage power distribution anti-misoperation device includes: Anti-backfeeding module: When the anti-backfeeding module detects that one of the two independent incoming lines loses power and the incoming line switch is in the closed state, the anti-backfeeding module prevents non-compliant loop closing operations; Anti-misoperation module: The anti-misoperation module is used to detect whether the line meets the loop closing conditions. When the line does not meet the loop closing conditions, the locking function is activated and the loop closing button fails; Power adjustment anti-misoperation auxiliary module: The power adjustment anti-misoperation auxiliary module is used to implement intelligent hot loop closing operations and avoid power outage operations; Interactive control screen: The interactive screen is used for intelligent power distribution operations and issues error alerts; State switching logic module: The state switching logic module completes the switching operation by controlling the target state of the switch, and determines whether the state switching conforms to hot switching or cold switching. When there is a risk of user power outage in the switching state selected by the staff, the interactive control screen will issue an error warning and stop the operation.

2. The low-voltage power distribution anti-misoperation device according to claim 1, wherein: The switch is set to three groups, and the switch is set at the two incoming line power supplies and between the power supplies on the bus side of the two incoming line switches.

3. The low-voltage power distribution anti-misoperation device according to claim 2, wherein: The anti-backfeeding module further includes a locking logic module. The locking logic module has a built-in relay. The anti-backfeeding module uses the locking logic to disconnect the built-in relay. The locking logic module prohibits the three switches from closing simultaneously to prevent backfeeding caused by improper closing.

4. A low-voltage power distribution anti-misoperation device according to claim 3, characterized in that: It also includes three sets of hot switching contacts, which are added to the secondary circuit of the power distribution system. During the hot switching operation, the three sets of hot switching contacts are closed, and when the hot switching ends, the three sets of hot switching contacts are separated.

5. A low-voltage power distribution anti-misoperation method, which applies a low-voltage power distribution anti-misoperation device as described in any one of claims 1 to 4, characterized in that: The low-voltage power distribution anti-misoperation method includes an anti-backfeeding method and a normal power adjustment anti-misoperation auxiliary operation method.

6. A low-voltage power distribution anti-misoperation method according to claim 5, characterized in that: The anti-backfeeding method includes the following steps: Step A1: When the low-voltage power distribution anti-misoperation device detects that any one of the incoming line power supplies loses power, it triggers the internal "three locks and two keys" locking logic, prohibits the three switches from closing simultaneously, and continuously detects the switch state; Step A2: When it is detected that two switches are in the closed position and one switch is in the open position, the switch in the open position is locked. When it is detected that one switch is in the closed position and two switches are in the open position, the locking function is not executed; Step A3: After the switch is locked against backfeeding, the unlocking method is that for two switches in the closed position, one of the switches is opened, and the locking is automatically released.

7. A low-voltage power distribution anti-misoperation method according to claim 6, characterized in that: The normal power adjustment anti-misoperation auxiliary operation method includes the following steps: Step B1: Add three sets of hot switching contacts to the secondary circuit. During the hot switching operation, the three sets of hot switching contacts are closed. When the hot switching ends, the three hot switching contacts are separated, and at the same time, the "three locks and two keys" anti-misoperation function of the secondary circuit is retained; Step B2: During normal power adjustment, when both incoming line power supplies have voltage and two switches are in the closed position, the device performs normal power adjustment anti-misoperation auxiliary operations, otherwise it is regarded as an abnormal state; Step B3: The state switching logic switches. The staff selects the target state of the switch through the interactive control screen to complete the switching operation. The switching operation state is presented in a graphical form. When it is judged that there is a risk of user power outage in the switching state selected by the staff, an error warning is issued and the operation is stopped.

8. A low-voltage power distribution anti-misoperation method according to claim 7, characterized in that: The implementation method for judging whether there is a risk in the switching state includes the following steps: Step S1: First, determine whether "hot transfer operation" is allowed. If hot transfer is not allowed, perform "cold transfer operation"; Step S2: Then, calculate whether the load after switching exceeds the transformer capacity. If it is detected that the load after transfer exceeds the transformer capacity, terminate the operation and give a voice prompt using the interactive control panel. When the transformer capacity allows, the interactive control panel gives a voice prompt to perform cold transfer operation or hot transfer operation.

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