Device and method for realizing differential protection when switching between main transformer switch and bypass switch

Abstract

The present invention relates to the field of power control technology, and discloses a device and method for realizing differential protection when a main transformer switch and a bypass switch are switched. The present invention obtains and analyzes the status signals of the main transformer switch and the bypass switch on each side of the main transformer. When only one main transformer switch or bypass switch on each side is in a closed state, the current corresponding to the closed switch is obtained to participate in the differential current calculation, and enter the differential protection logic, otherwise the differential protection is exited; the present invention modifies the main transformer differential protection program, adds "soft switching" of differential current under the bypass wiring form, reduces the complexity and risk of manual current switching, improves the operating efficiency, and is beneficial to ensuring the reliability of power supply.

Description

Technical Field

[0001] The present invention relates to the technical field of power control, and in particular to a device and method for realizing differential protection when a main transformer switch and a bypass switch are switched. Background Art

[0002] When the primary main connection of the substation is a main bus with bypass, when the bypass switch replaces the main transformer switch for operation, the current of the main transformer differential protection device that protects the main transformer needs to be switched to the current in the bypass state to ensure the normal operation of the main transformer differential protection.

[0003] When the differential protection current is switched by bypass operation, the operator currently performs manual switching via the current switching terminal. This operation procedure is complicated and easily causes risks such as the current switching terminal loosening and the current loop opening. It is also inefficient and the main transformer loses the main protection for a long time. Summary of the invention

[0004] The present invention provides a device and method for realizing differential protection when a main transformer switch and a bypass switch are switched, which solves the technical problems of the existing main transformer protection that the differential protection current switching operation procedure is complicated, inefficient and prone to safety risks.

[0005] A first aspect of the present invention provides a device for implementing differential protection when a main transformer switch and a bypass switch are switched, comprising:

[0006] The analog quantity acquisition module is used to sample the currents on each side of the main transformer and the bypass current, including a transformer high-side current sampling unit, a transformer high-side bypass current sampling unit, a transformer middle-side current sampling unit, and a transformer low-side current sampling unit;

[0007] A switch quantity determination module is used to perform logic XOR gate calculation on the state signals of the main transformer switch and the bypass switch on each side of the main transformer, so that when only one main transformer switch or bypass switch on each side is in a closed state, a switch quantity signal is output, and the switch quantity signal includes an identifier of the closed switch;

[0008] The differential protection execution module is connected to the analog quantity acquisition module and the switch quantity determination module, and is used to obtain the current corresponding to the identification of the closed switch from the analog quantity acquisition module when receiving the switch quantity signal, perform differential current calculation based on the obtained current and enter the differential protection logic.

[0009] According to an achievable manner of the first aspect of the present invention, the switch quantity determination module is further configured to output a blocking signal when not only one main transformer switch or bypass switch on each side is in a closed state, or when the operating states of the above switch quantities are all in an unclosed state;

[0010] The differential protection execution module is also used to lock the outlet circuit of the differential protection when receiving the locking signal.

[0011] According to an achievable manner of the first aspect of the present invention, the switch value determination module includes:

[0012] The first signal acquisition unit is used to collect the status signal of the main transformer switch on the high-voltage side;

[0013] A second signal acquisition unit is used to acquire a state signal of the high-side bypass switch;

[0014] The third signal acquisition unit is used to collect the status signal of the main transformer switch at the transformer middle side;

[0015] A fourth signal acquisition unit, used for acquiring a status signal of a side switch of a transformer;

[0016] A fifth signal acquisition unit, used for acquiring a status signal of a differential protection pressure plate;

[0017] and a first XOR gate unit, a second XOR gate unit, a third AND gate unit, and a fourth AND gate unit for performing logic calculations;

[0018] Among them, the input end of the first XOR unit is connected to the first signal acquisition unit and the second signal acquisition unit; the input end of the second XOR gate unit is connected to the third signal acquisition unit and the fourth signal acquisition unit; the output end of the first XOR gate unit and the output end of the second XOR gate unit are connected to the input end of the third AND gate unit, the output end of the third AND gate unit and the fifth signal acquisition unit are connected to the input end of the fourth AND gate unit, and the output end of the fourth AND gate unit is connected to the differential protection execution module.

[0019] A second aspect of the present invention provides a method for implementing differential protection when a main transformer switch and a bypass switch are switched, the method comprising:

[0020] Obtaining status signals of main transformer switches and bypass switches on each side of the main transformer, wherein the main transformer switches and bypass switches on each side include a main transformer switch on a high transformer side, a bypass switch on a high transformer side, a main transformer switch on a middle transformer side, and a bypass switch on a middle transformer side;

[0021] Analyze all acquired status signals;

[0022] If only one main transformer switch or bypass switch on each side is in a closed state, the current corresponding to the closed switch is obtained;

[0023] The differential current is calculated based on the acquired current and enters the differential protection logic.

[0024] According to an achievable manner of the second aspect of the present invention, the method further includes:

[0025] If there is not only one main transformer switch or bypass switch on each side that is in the closed state, or the operating states of the above-mentioned switch quantities are all in the unclosed state, a locking signal is output to lock the outlet circuit of the differential protection.

[0026] A third aspect of the present invention provides a device for implementing differential protection when a main transformer switch and a bypass switch are switched, the device comprising:

[0027] The first acquisition module is used to obtain the status signals of the main transformer switches and bypass switches on each side of the main transformer, wherein the main transformer switches and bypass switches on each side include the main transformer switch on the high-voltage transformer side, the bypass switch on the high-voltage transformer side, the main transformer switch on the middle-voltage transformer side, and the bypass switch on the middle-voltage transformer side;

[0028] An analysis module, used for analyzing all acquired status signals;

[0029] A second acquisition module is used to acquire the current corresponding to the closed switch when only one main transformer switch or bypass switch on each side is in a closed state;

[0030] The differential protection module is used to perform differential current calculation according to the acquired current and enter the differential protection logic.

[0031] According to an achievable manner of the third aspect of the present invention, the device further includes:

[0032] The locking control module is used to output a locking signal to lock the output circuit of the differential protection when more than one main transformer switch or bypass switch on each side is in the closed state, or when the operating states of the above-mentioned switch quantities are all in the unclosed state.

[0033] A fourth aspect of the present invention provides a device for implementing differential protection when a main transformer switch and a bypass switch are switched, comprising:

[0034] A memory for storing instructions; wherein the instructions are instructions for implementing the method for implementing differential protection when the main transformer switch and the bypass switch are switched as described in any of the above-mentioned methods;

[0035] A processor is used to execute instructions in the memory.

[0036] A fifth aspect of the present invention is a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a method for realizing differential protection when a main transformer switch and a bypass switch are switched as described in any of the above-mentioned methods.

[0037] It can be seen from the above technical solutions that the present invention has the following advantages:

[0038] The present invention obtains and analyzes the status signals of the main transformer switches and bypass switches on each side of the main transformer. When only one main transformer switch or bypass switch on each side is in a closed state, the current corresponding to the closed switch is obtained to participate in the differential current calculation and enter the differential protection logic, otherwise the differential protection is exited. The present invention modifies the main transformer differential protection program and adds "soft switching" of the differential current under the bypass wiring form, thereby reducing the complexity and risk of manual current switching, improving the operating efficiency, and being beneficial to ensuring the reliability of power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0040] Figure 1 A structural block diagram of a device for implementing differential protection when a main transformer switch and a bypass switch are switched, provided as an optional embodiment of the present invention;

[0041] Figure 2 A schematic diagram of a switch value determination module provided for an optional embodiment of the present invention;

[0042] Figure 3 A flow chart of a method for implementing differential protection when a main transformer switch and a bypass switch are switched, provided as an optional embodiment of the present invention;

[0043] Figure 4 A structural block diagram of a device for implementing differential protection when a main transformer switch and a bypass switch are switched, provided in accordance with another optional embodiment of the present invention.

[0044] Reference numerals:

[0045] 1-analog quantity acquisition module; 2-switch quantity determination module; 3-differential protection execution module; 10-first acquisition module; 20-analysis module; 30-second acquisition module; 40-differential protection module; 50-locking control module. DETAILED DESCRIPTION

[0046] The embodiment of the present invention provides a device and method for realizing differential protection when the main transformer switch and the bypass switch are switched, which is used to solve the technical problems that the differential protection current switching operation procedure of the existing main transformer protection is complicated, inefficient and easy to cause safety risks.

[0047] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] The invention provides a device for realizing differential protection when a main transformer switch and a bypass switch are switched.

[0049] See also Figure 1 , Figure 1 A structural block diagram of a device for implementing differential protection when a main transformer switch and a bypass switch are switched is shown according to an embodiment of the present invention.

[0050] The device for implementing differential protection when a main transformer switch and a bypass switch are switched provided by an embodiment of the present invention includes:

[0051] Analog quantity acquisition module 1, used for sampling the current on each side of the main transformer and the bypass current, including a transformer high-side current sampling unit, a transformer high-side bypass current sampling unit, a transformer middle-side current sampling unit and a transformer low-side current sampling unit;

[0052] The switch quantity determination module 2 is used to perform logic XOR gate calculation on the state signals of the main transformer switch and the bypass switch on each side of the main transformer, so that when only one main transformer switch or bypass switch on each side is in a closed state, a switch quantity signal is output, and the switch quantity signal includes an identifier of the closed switch;

[0053] The differential protection execution module 3 is connected to the analog quantity acquisition module and the switch quantity determination module, and is used to obtain the current corresponding to the identifier of the closed switch from the analog quantity acquisition module when receiving the switch quantity signal, perform differential current calculation based on the obtained current and enter the differential protection logic.

[0054] Among them, each side of the main transformer includes a main transformer high voltage side and a main transformer medium voltage side; the differential protection logic is pre-configured in the main transformer differential protection device, and the differential protection logic is used to realize the differential protection function of the main transformer.

[0055] In an achievable manner, the switch quantity determination module 2 is further configured to output a blocking signal when more than one main transformer switch or bypass switch on each side is in a closed state, or when the operating states of the above switch quantities are all in an unclosed state;

[0056] The differential protection execution module 3 is also used to lock the outlet circuit of the differential protection when receiving the locking signal.

[0057] By blocking the output circuit of the differential protection, it is possible to prevent the differential protection from malfunctioning due to the inconsistency between the current circuit and the actual operation mode. In one possible implementation, Figure 2 As shown, the switch value determination module 3 includes:

[0058] The first signal acquisition unit is used to collect the status signal of the main transformer switch on the high-voltage side;

[0059] A second signal acquisition unit is used to acquire a state signal of the high-side bypass switch;

[0060] The third signal acquisition unit is used to collect the status signal of the main transformer switch at the transformer middle side;

[0061] A fourth signal acquisition unit, used for acquiring a status signal of a side switch of a transformer;

[0062] A fifth signal acquisition unit, used for acquiring a status signal of a differential protection pressure plate;

[0063] and a first XOR gate unit, a second XOR gate unit, a third AND gate unit, and a fourth AND gate unit for performing logic calculations;

[0064] Among them, the input end of the first XOR unit is connected to the first signal acquisition unit and the second signal acquisition unit; the input end of the second XOR gate unit is connected to the third signal acquisition unit and the fourth signal acquisition unit; the output end of the first XOR gate unit and the output end of the second XOR gate unit are connected to the input end of the third AND gate unit, the output end of the third AND gate unit and the fifth signal acquisition unit are connected to the input end of the fourth AND gate unit, and the output end of the fourth AND gate unit is connected to the differential protection execution module.

[0065] Through the switch quantity determination module 2 and the differential protection execution module 3, the differential protection function can be effective when only one of the operating pressure plates of each main transformer switch or bypass switch is put into operation, and the differential protection function will be exited when none of them are put into operation or all of them are put into operation.

[0066] The present invention also provides a method for realizing differential protection when a main transformer switch and a bypass switch are switched.

[0067] See also Figure 3 , Figure 3 A flow chart of a method for implementing differential protection when a main transformer switch and a bypass switch are switched is shown in an embodiment of the present invention.

[0068] The method comprises:

[0069] Step S1, obtaining status signals of main transformer switches and bypass switches on each side of the main transformer, wherein the main transformer switches and bypass switches on each side include a main transformer switch on a high transformer side, a bypass switch on a high transformer side, a main transformer switch on a middle transformer side, and a bypass switch on a middle transformer side.

[0070] Step S2, analyzing all acquired status signals.

[0071] Step S3: If only one main transformer switch or bypass switch on each side is in a closed state, the current corresponding to the closed switch is obtained.

[0072] In specific implementation, if only the state of the main transformer switch on the high-voltage side of the high-voltage side is in the closed state, the current of the high-voltage side is obtained; if only the state of the bypass switch on the high-voltage side of the high-voltage side is in the closed state, the bypass current of the high-voltage side is obtained; if only the state of the main transformer switch on the medium-voltage side of the medium-voltage side is in the closed state, the current of the medium-voltage side is obtained; if only the state of the bypass switch on the medium-voltage side of the medium-voltage side is in the closed state, the bypass current of the medium-voltage side is obtained.

[0073] Among them, corresponding sampling units can be set to collect the currents of the main transformer switches and bypass switches on each side of the main transformer.

[0074] Step S4, performing differential current calculation according to the acquired current and entering differential protection logic.

[0075] The differential protection logic is pre-configured in the main transformer differential protection device, and the differential protection logic is used to implement the differential protection function for the main transformer.

[0076] In one implementation, the method further includes:

[0077] If more than one main transformer switch or bypass switch is in the closed state, or the operating states of the above switch quantities are all in the unclosed state, a blocking signal is output to block the outlet circuit of the differential protection.

[0078] By locking the output circuit of the differential protection, it is possible to prevent the differential protection from malfunctioning due to inconsistency between the current circuit and the actual operating mode.

[0079] The present invention also provides a device for realizing differential protection when the main transformer switch and the bypass switch are switched.

[0080] See also Figure 4 , Figure 4 A structural block diagram of a device for implementing differential protection when a main transformer switch and a bypass switch are switched is shown according to an embodiment of the present invention.

[0081] An embodiment of the present invention provides a device for implementing differential protection when a main transformer switch and a bypass switch are switched, comprising:

[0082] The first acquisition module 10 is used to obtain the status signals of the main transformer switches and bypass switches on each side of the main transformer, wherein the main transformer switches and bypass switches on each side include the main transformer switch on the high-voltage transformer side, the bypass switch on the high-voltage transformer side, the main transformer switch on the middle-voltage transformer side, and the bypass switch on the middle-voltage transformer side;

[0083] An analysis module 20, used for analyzing all acquired status signals;

[0084] The second acquisition module 30 is used to acquire the current corresponding to the closed switch when only one main transformer switch or bypass switch on each side is in the closed state;

[0085] The differential protection module 40 is used to perform differential current calculation according to the acquired current and enter the differential protection logic.

[0086] In one possible implementation, the device further includes:

[0087] The locking control module 50 is used to output a locking signal to lock the outlet circuit of the differential protection when more than one main transformer switch or bypass switch on each side is in the closed state.

[0088] The present invention also provides a device for realizing differential protection when a main transformer switch and a bypass switch are switched, comprising:

[0089] A memory for storing instructions; wherein the instructions are instructions for implementing the method for implementing differential protection when the main transformer switch and the bypass switch are switched as described in any one of the above embodiments;

[0090] A processor is used to execute instructions in the memory.

[0091] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the method for realizing differential protection when switching between a main transformer switch and a bypass switch as described in any one of the above embodiments is implemented.

[0092] The above-mentioned embodiment of the present invention modifies the main transformer differential protection program and adds "soft switching" of differential current under the bypass wiring form, thereby reducing the complexity and risk of manual current switching, improving operating efficiency, and being beneficial to ensuring the reliability of power supply.

[0093] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes and effects of the above-described devices, modules and units can refer to the corresponding processes and effects in the aforementioned method embodiments, and will not be repeated here.

[0094] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0095] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0096] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0097] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0098] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for realizing differential protection when switching between a main transformer switch and a bypass switch, characterized in that: include: The analog quantity acquisition module is used to sample the current on each side of the main transformer and the bypass current, including a transformer high-side current sampling unit, a transformer high-bypass current sampling unit, a transformer middle-side current sampling unit, and a transformer low-side current sampling unit; A switch quantity determination module is used to perform logic XOR gate calculation on the state signals of the main transformer switch and the bypass switch on each side of the main transformer, so that when only one main transformer switch or bypass switch on each side is in a closed state, a switch quantity signal is output, and the switch quantity signal includes an identifier of the closed switch; A differential protection execution module is connected to the analog quantity acquisition module and the switch quantity determination module, and is used to obtain the current corresponding to the identifier of the closed switch from the analog quantity acquisition module when receiving the switch quantity signal, perform differential current calculation according to the obtained current, and enter the differential protection logic; The switch quantity determination module comprises: The first signal acquisition unit is used to collect the status signal of the main transformer switch on the high-voltage side; A second signal acquisition unit, used for acquiring a status signal of the high-side bypass switch; The third signal acquisition unit is used to collect the status signal of the main transformer switch at the transformer middle side; A fourth signal acquisition unit, used for acquiring a status signal of a bypass switch on the transformer side; A fifth signal acquisition unit, used for acquiring a status signal of a differential protection pressure plate; and a first XOR gate unit, a second XOR gate unit, a third AND gate unit, and a fourth AND gate unit for performing logic calculations; Among them, the input end of the first XOR unit is connected to the first signal acquisition unit and the second signal acquisition unit; the input end of the second XOR gate unit is connected to the third signal acquisition unit and the fourth signal acquisition unit; the output end of the first XOR gate unit and the output end of the second XOR gate unit are connected to the input end of the third AND gate unit, the output end of the third AND gate unit and the fifth signal acquisition unit are connected to the input end of the fourth AND gate unit, and the output end of the fourth AND gate unit is connected to the differential protection execution module.

2. The device for realizing differential protection when switching between the main transformer switch and the bypass switch according to claim 1 is characterized in that: The switch quantity determination module is also used to output a blocking signal when the operation state of more than one main transformer switch or bypass switch on each side is in a closed state, or when the operation states of the above switch quantities are all in an unclosed state; The differential protection execution module is also used to lock the outlet circuit of the differential protection when receiving the locking signal.

3. The device for realizing differential protection when switching between the main transformer switch and the bypass switch according to claim 1 is characterized in that: The device also includes: A first acquisition module is used to acquire status signals of main transformer switches and bypass switches on each side of the main transformer, wherein the main transformer switches and bypass switches on each side include a main transformer switch on a transformer high side, a bypass switch on a transformer high side, a main transformer switch on a transformer middle side, and a bypass switch on a transformer middle side; An analysis module, used for analyzing all acquired status signals; A second acquisition module is used to acquire the current corresponding to the closed switch when only one main transformer switch or bypass switch on each side is in a closed state; The differential protection module is used to perform differential current calculation according to the acquired current and enter the differential protection logic.

4. The device for realizing differential protection when switching between the main transformer switch and the bypass switch according to claim 3 is characterized in that: The device also includes: The locking control module is used to output a locking signal to lock the output circuit of the differential protection when more than one main transformer switch or bypass switch on each side is in the closed state, or when the operating states of the above-mentioned switch quantities are all in the unclosed state.

5. A method for realizing differential protection when switching between a main transformer switch and a bypass switch, characterized in that: The method for implementing differential protection when the main transformer switch and the bypass switch are switched is performed by the device for implementing differential protection when the main transformer switch and the bypass switch are switched as claimed in claim 1, and the method comprises: Obtaining status signals of the main transformer switches and bypass switches on each side of the main transformer, wherein the main transformer switches and bypass switches on each side include the main transformer switch on the high-voltage side, the bypass switch on the high-voltage side, the main transformer switch on the middle-voltage side, and the bypass switch on the middle-voltage side; Analyze all acquired status signals; If only one main transformer switch or bypass switch on each side is in a closed state, the current corresponding to the closed switch is obtained; The differential current is calculated based on the acquired current and enters the differential protection logic.

6. The method for realizing differential protection when switching between the main transformer switch and the bypass switch according to claim 5 is characterized in that: The method further comprises: If more than one main transformer switch or bypass switch is in the closed state, or the operating states of the above switch quantities are all in the unclosed state, a blocking signal is output to block the outlet circuit of the differential protection.

7. A device for realizing differential protection when switching between a main transformer switch and a bypass switch, characterized in that: include: A memory for storing instructions; wherein the instructions are instructions for implementing the method for implementing differential protection when the main transformer switch and the bypass switch are switched as claimed in claim 5 or 6; A processor is used to execute instructions in the memory.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by the processor, the method for realizing differential protection when the main transformer switch and the bypass switch are switched as claimed in claim 5 or 6 is implemented.

Images