Configuration-free CT primitive setting method suitable for transformer substation

Abstract

The invention discloses a CT primitive setting method suitable for transformer substation configuration-free, which comprises the following steps of: setting attribute parameters, geometrical shapes and logic models of a CT aiming at the application requirements that a new generation of transformer substation configuration-free technology needs to realize automatic setting of CT polarity parameters and automatic configuration of virtual terminals, and realizing CT geometrical shape display and logic model information instantiation through the CT attribute parameters. In combination with application requirements of specific secondary equipment on CT polarity parameters and CT winding configuration, far-end and near-end strategies of CT polarity ends and interval primitives and association strategies of the CT polarity ends and large-size and small-size buses are set, so that application association and logic conversion among CT attribute parameters, CT geometric shapes and CT logic models are realized; and finally, realizing automatic setting of polarity parameters of related secondary equipment, and supporting realization of a function of automatically subscribing to a virtual loop by virtual terminals with different polarity attributes.

Description

Technical Field

[0001] This invention relates to the technical field of automatic configuration of files in intelligent substations, and specifically to a method for setting CT elements that is suitable for configuration-free operation in substations. Background Technology

[0002] Currently, the technical specifications for new-generation high-reliability substations propose a configuration-free technology. This technology describes the topological relationships between secondary equipment by defining parameters, eliminating the need to directly pull virtual terminals to generate SCDs. At the design end, the entire substation bay design, PT / CT design, and primary / secondary relationship design can be completed by drawing a primary topology diagram. Based on the corresponding design information, configuration parameters such as bay number and CT polarity are automatically generated. Setting these parameters into secondary equipment that supports the configuration-free algorithm enables configuration-free applications. While parameters such as bay number can be automatically generated based on bay location information and scheduling name according to a built-in strategy, the automatic generation of CT polarity parameters still requires the aid of an algorithm.

[0003] In addition, the SSD (System Specification Configuration) file, as a document describing the system specification configuration of the substation, describes the logical relationships between the substation bays, primary equipment, and secondary equipment. In particular, it describes the relationship between PTs / CTs and their windings, polarity information, and secondary equipment and sampling channels. It is the core of realizing the same-source channel configuration, such as the same-source channel configuration of waveform recorders and the same-source channel configuration of protection devices. The realization of the same-source channel configuration is crucial for a series of advanced applications such as transient same-source comparison, steady-state same-source comparison, primary and secondary mismatch comparison, fault inspection, fault waveform analysis, and fault distance calculation.

[0004] By searching relevant technologies, it was found that there is currently no technology to solve the technical problems of automatic generation of CT polarity parameters and auxiliary configuration of the same source channel from graphic design to application. The relevant configuration work is mainly completed manually, which has inherent defects such as low efficiency and inability to guarantee accuracy. In particular, the new generation of high-reliability substations defines CT polarity as a type of configuration-free parameter. How to convert its parameters from graphic description to the final parameter value directly affects whether the relevant secondary equipment can generate the corresponding configuration-free parameters based on the graphics, as well as the consistency between the virtual terminal circuit generated by the configuration-free parameters and the actual primary CT design polarity.

[0005] CT involves multiple stages, including primitive definition, graphic display, model conversion, and polarity parameter generation. Reliable methods are needed to achieve user-friendly interface interaction and polarity parameter generation, supporting advanced applications such as SSD configuration and automatic generation of configuration parameters. Summary of the Invention

[0006] To address the technical challenges of current high-reliability substation configuration-free technologies failing to achieve automatic setting of CT polarity parameters and automatic configuration of virtual terminals, this technical solution provides a CT element setting method adapted to configuration-free substations. This method includes steps for setting CT attribute parameters, geometry, and logic models. CT attribute parameters enable the display of CT geometry and instantiation of logic model information. Combined with the specific application requirements of secondary equipment for CT polarity parameters and CT winding configuration, it sets far-end and near-end strategies for CT polarity terminals and bay elements, as well as association strategies for CT polarity terminals and large and small busbars. This achieves application association and logical conversion between CT attribute parameters, CT geometry, and CT logic models, ultimately enabling automatic setting of polarity parameters for relevant secondary equipment. It also supports the automatic subscription of virtual circuits to virtual terminals with different polarity attributes, effectively solving the aforementioned problems.

[0007] This invention is achieved through the following technical solution:

[0008] A method for setting up CT elements in substations without requiring configuration includes the following steps:

[0009] Step 1: Set the attribute parameters of the CT, including CT parameters and winding parameters. The CT parameters include scheduling name, associated interval, number of windings, polarity end, and polarity end bus number. The winding parameters include winding selection, type, transformation ratio, associated secondary equipment, phase selection, and associated sampling channel.

[0010] Step 2: Set the geometry of the CT and use the symbol * to indicate the geometric polarity of the CT;

[0011] Step 3: Set up the application logic model for CT to describe the CT polarity in logical relationships;

[0012] Step 4: Based on the set CT geometry and logic model, realize the automatic setting of IED polarity parameters and the application of sampling channel homogeneous configuration.

[0013] Furthermore, the specific operation method for setting the CT attribute parameters as described in step 1 includes the following steps:

[0014] The attribute parameters of a CT characterize the attributes of the CT in various dimensions, enabling the CT to self-describe the parameters and functions required by the application side. By defining the attribute parameters of the CT, a clear and complete unique description of each CT in the substation is achieved. Specifically, this includes the following dimension definitions:

[0015] Step 1.1: Set CT parameters, including:

[0016] Step 1.11: Determine the scheduling name: The scheduling side issues a name for this CT, which is used as the globally unique name of this CT;

[0017] Step 1.12: Determine the associated interval: Associate the intervals defined in the main wiring diagram and use them as the application scope description of this CT;

[0018] Step 1.13: Determine the number of windings: Obtain or input the number of windings present in this CT, which will be used as a description of the CT's ability to support external devices;

[0019] Step 1.14: Determine the polarity end: Define the polarity end of this CT, with enumerated values ​​including 1 and 2, representing the polarity end on both sides of the CT, respectively;

[0020] Step 1.15: Determine the polarity bus number: This indicates the bus number connected to the polarity end of this CT. Enumerated values ​​include none, large number, and small number.

[0021] Step 1.2: Set the winding parameters, including:

[0022] Step 1.21: Select the winding: Select a specific winding, and after selection, determine the winding type, turns ratio, associated secondary equipment, phase selection, and associated sampling channel, and use it as the self-description and external relationship description of this winding.

[0023] Furthermore, step 1.21, which involves determining the winding type, turns ratio, associated secondary equipment, phase selection, and associated sampling channel, specifically includes:

[0024] Determining the type of the winding means determining the specification type of this CT winding and using it as the specification description of this winding.

[0025] Determining the turns ratio of the winding refers to determining the primary and secondary rated current turns ratios of the CT winding, which are used as parameters to describe the winding and are applicable to the relationship conversion between primary and secondary currents.

[0026] The process of determining the associated secondary equipment of the winding refers to determining the secondary equipment connected to this CT winding, which is represented by the defined IED name;

[0027] The determination of the phase selection of the winding is to select A, B, C, zero sequence, gap, or single phase, which indicates the corresponding phase winding under this CT winding;

[0028] The process of determining the associated sampling channel for the winding involves selecting the sampling channel signal path in the model file corresponding to the IED.

[0029] Furthermore, the winding selection can also precisely associate the CT winding with the sampling channels of the secondary equipment. Combined with the definition of parameters such as CT ratio and polarity, it can help to define the same source channels of different equipment. If the sampling channels of different equipment are all associated with the same winding of the target CT, then based on this association, the recording channels of all equipment can be automatically selected as a group of same source channels to realize transient same source comparison and steady-state same source comparison applications.

[0030] Furthermore, the geometry of the CT described in step 2 consists of two basic primitives: circles and the symbol *. Connection points are defined on both sides of the circle. Several circles represent the number of windings in the CT. The * symbol is placed outside the circle on one side to indicate polarity. When the CT is displayed, it can be either a summary display or a full winding display. The polarity end is also displayed simultaneously with the CT display. The symbol * represents the geometric polarity end of the CT. This polarity end is defined by setting the polarity end parameter in the CT parameters. The default layout of the CT primitive is vertically connected. When the polarity end parameter is 1, the symbol * is on the upper left side of the CT primitive. When the polarity end parameter is 2, the symbol * is on the lower left side of the CT primitive. The vertical and horizontal layouts of the CT primitive in the graphic are obtained by rotating the primitive at an angle.

[0031] Furthermore, the CT application logic model described in step 3 describes the logical attributes of CT in different application scenarios; when applying CT, the polarity parameters provided by the design side are based on geometric relationships, while the application side needs to obtain the logical relationships of the polarity parameters.

[0032] Based on the main wiring diagram, the connection relationships are described, and the near-end and far-end relationships between the CT polarity terminals and the target bay are defined. Any bay contains either a circuit breaker or a main device. If a circuit breaker is present, the circuit breaker is used as the main graphic element of the bay. If only the main device is present, the main device is used as the main graphic element. The following two geometric logical relationships exist between the main graphic element of any bay and any CT:

[0033] The polarity of a CT image is at the proximal end of the main image element; the polarity of a CT image is at the distal end of the main image element.

[0034] For bus bays, in addition to obtaining the polarity proximal-distal relationship between the CT and the bus, based on the CT definition, the concepts of large and small bus are further introduced, resulting in the following two logical relationships:

[0035] The polarity of the CT is on the small busbar side; the polarity of the CT is on the large busbar side.

[0036] Furthermore, the logical implementation of the CT application logic model includes the following specific details:

[0037] For non-busbar intervals: calculate the distance l1 between the center point of the main graphic element and the polarity end symbol, and the distance l2 between the center point of the main graphic element and the center point of the CT winding, respectively. Compare the two. When l1 is less than l2, the polarity end of the CT is near the main graphic element. When l1 is greater than l2, the polarity end of the CT is far from the main graphic element.

[0038] For bus bays:

[0039] Method 1: Setting the polarity of the specified CT on the small or large busbar side to obtain the logical result, without the need for complex logical operations;

[0040] Method 2: Determine the bus number of the nearest busbar connecting both sides of the CT. The bus number is defined according to the busbar, such as the bus numbers of busbar 1, busbar 2, and busbar 3 being 1, 2, and 3 respectively. Determine the large busbar and the small busbar, select the small busbar, and calculate the distance l1 between the center point of the main graphic element of the small busbar and the polarity end symbol, and the distance l2 between the center point of the main graphic element and the center point of the CT winding. Compare the two. When l1 is less than l2, the polarity end of the CT is on the small busbar side; when l1 is greater than l2, the polarity end of the CT is on the large busbar side.

[0041] Furthermore, step 4, which involves automatically setting the IED polarity parameters based on the configured CT geometric and logical model, includes the following steps:

[0042] Step 4.1: Obtain Strategy 1: Arbitrary Interval Protection. There is a CT polarity parameter that needs to be set. Based on this parameter, determine the SV virtual circuit automatic configuration strategy with positive and negative virtual terminals. First, based on the attribute information of the defined CT object, determine the target CT in the main wiring diagram. Based on the algorithm, obtain the near end and far end relationship between the polarity terminal of the CT and the main graphic element of this interval. If the result is near end, the corresponding parameter is 0, that is, the reverse virtual terminal is pulled. If the result is far end, the corresponding parameter is 1, that is, the positive virtual terminal is pulled.

[0043] Step 4.2: Obtain Strategy 2: Based on the algorithm, obtain the relationship between the polarity end of the CT and the main primitive and the proximal and distal ends of the main primitive. For any result that is proximal, the corresponding parameter is 1, that is, pull the positive virtual terminal. For any result that is distal, the corresponding parameter is 0, that is, pull the negative virtual terminal.

[0044] Step 4.3: Store Strategy 1 and Strategy 2 in the application's tools along with the specific type of IED, and generate different strategies for different types of IEDs;

[0045] Step 4.4: For the bus tie bay, determine the CT polarity strategy 3: When the bus number of the CT polarity terminal of the bus tie bay is small, the bus protection selects the CT polarity parameter as positive, that is, selects the positive virtual terminal of the bus tie bay SV.

[0046] Step 4.5: Automatically select and configure the positive or negative virtual terminals of the bus tie bay for bus protection based on strategy 3;

[0047] Step 4.6: Determine CT polarity strategy 4: When the bus number of the CT polarity terminal of the bus tie bay is large, the bus protection selects the CT polarity parameter as positive, that is, selects the SV (positive) virtual terminal of the bus tie bay.

[0048] Step 4.7: Based on strategy 1, strategy 2, strategy 3, and strategy 4, automatically generate the polarity parameters.

[0049] Extending this further, the compatibility of the above examples can be easily verified for any other method. For example, in the case of internal bridge connection and expanded internal bridge connection, the main transformer protection also has the problem of selecting (positive) and (reverse) virtual terminals for the current sampling circuit of the segmented bay. Applying the CT polarity selection strategy 1 for general non-busbar bays described in Example 1, that is, if the CT polarity is near the end, the main transformer protection pulls the (reverse) virtual terminal, and if the CT polarity is far the end, the main transformer protection pulls the (positive) virtual terminal, which conforms to the design specifications of the bridge current virtual terminal of the main transformer protection under the internal bridge connection and expanded internal bridge connection methods.

[0050] In fact, the number of protections with defined polarities in engineering is limited. Based on the above strategy, the polarity parameters can be automatically generated.

[0051] Specifically, the polarity definitions of the internal logic of some protection systems may differ. For example, some bus protection systems fix the positive polarity terminal of the bus tie on the large bus side, pulling the (positive) virtual terminal of the internal virtual terminal. In this case, it is only necessary to simply adjust to CT polarity strategy 4 to quickly achieve adaptation. Furthermore, it is also possible to combine the information of specific differentiated equipment manufacturers to solidify the selection of CT polarity strategy for the corresponding manufacturer's equipment.

[0052] Furthermore, the sampling channel homogeneous configuration described in step 4 specifically includes: a separate definition of the winding, detailed association between the CT winding and the sampling channels of the secondary equipment, and, in conjunction with the definition of CT ratio and polarity, assistance in defining homogeneous channels for different equipment in the CT winding. The sampling channels of different equipment are all associated with the same winding of the target CT. Based on this association, the waveform recording channels of all equipment are automatically selected as a group of homogeneous channels, thus realizing the normalized association description of the sampling channels of all associated equipment from the source.

[0053] Beneficial effects

[0054] The present invention proposes a CT element setting method adapted to substations without configuration, which has the following advantages compared with the prior art:

[0055] 1. This invention provides a CT element design method adapted to the configuration-free operation of a new generation of high-reliability substations. Based on this method, the geometric element definition, model information definition, and polarity information definition of the CT are realized.

[0056] 2. This invention provides a complete technical solution for the definition of CTs in various substations, including new-generation high-reliability substations. In particular, it provides a specific and executable method for the logical conversion from the graphic design rules of CTs to the non-graphical application side. It proposes a logical description method based on the relationship between the main graphic element of the interval and the far and near ends of the CT polarity graphic element, and a logical description method based on the relationship between the CT polarity graphic element and the large and small busbars. It further succinctly establishes a strategy description from geometric relationship to logical relationship and designs several corresponding relationship conversion implementation methods. This allows the design side to obtain the logical information required by the application side based on the relationship conversion strategy after drawing a geometric graphic. It can effectively support the implementation of applications related to CTs, such as SSD configuration and automatic generation of polarity configuration parameters. Attached Figure Description

[0057] Figure 1 This is the overall flowchart of the present invention.

[0058] Figure 2 This is a schematic diagram of setting CT parameters in this invention.

[0059] Figure 3 This is a schematic diagram of the CT display setup in this invention.

[0060] Figure 4 This is a schematic diagram of the CT configuration for the 3 / 2 wiring method in this invention.

[0061] Figure 5 This is a schematic diagram of the virtual terminal for receiving the dual-switch line protection current in this invention.

[0062] Figure 6 This is a schematic diagram of the virtual terminal for receiving the 3 / 2 busbar protection current in this invention.

[0063] Figure 7 This is a schematic diagram of the virtual terminal for receiving the protection current of the double busbar double branch connection in this invention.

[0064] Figure 8 This is a schematic diagram of the dual busbar dual branch line CT configuration in this invention. Detailed Implementation

[0065] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. The described embodiments are merely some embodiments of the present invention, and not all embodiments. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the design concept of the present invention should fall within the protection scope of the present invention.

[0066] Example 1:

[0067] A method for setting up CT elements in substations without requiring configuration, such as Figure 1 As shown, it includes the following steps:

[0068] Step 1: Set the CT attribute parameters, such as Figure 2 As shown, this includes CT parameters and winding parameters. CT parameters include scheduling naming, associated interval, number of windings, polarity terminals, and polarity terminal bus numbers. Winding parameters include winding selection, type, turns ratio, associated secondary equipment, phase selection, and associated sampling channel. The specific operation method includes the following steps:

[0069] The attribute parameters of a CT characterize the attributes of the CT in various dimensions, enabling the CT to self-describe the parameters and functions required by the application side. By defining the attribute parameters of the CT, a clear and complete unique description of each CT in the substation is achieved. Specifically, this includes the following dimension definitions:

[0070] Step 1.1: Set CT parameters, including:

[0071] Step 1.11: Determine the scheduling name: The scheduling side issues the name of this CT (e.g., test line 1 CT), which is used as the globally unique name of this CT;

[0072] Step 1.12: Determine the associated interval: Associate the intervals defined in the main wiring diagram (such as test line 1) and use them as the application scope description of this CT;

[0073] Step 1.13: Determine the number of windings: Obtain or input the number of windings present in this CT (which can be flexibly defined), and use it as a description of the CT's ability to support external devices;

[0074] Step 1.14: Determine the polarity end: Define the polarity end of this CT, with enumerated values ​​including 1 and 2, representing the polarity end on both sides of the CT, respectively;

[0075] Step 1.15: Determine the polarity bus number: This indicates the bus number connected to the polarity end of this CT. Enumerated values ​​include none, large number, and small number.

[0076] Step 1.2: Set the winding parameters, including:

[0077] Step 1.21: Select the winding: Select a specific winding, and after selection, determine the winding type, turns ratio, associated secondary equipment, phase selection, and associated sampling channel. This will serve as the self-description and external relationship description for this winding. Specifically, the winding type, turns ratio, associated secondary equipment, phase selection, and associated sampling channel are determined as follows:

[0078] Determining the type of the winding means determining the specification type of the CT winding (e.g., 5P40, which indicates a linear range of 50 times the rated current, used for protection, and an accuracy class of 5) and using it as the specification description of the winding.

[0079] Determining the turns ratio of the winding refers to determining the primary and secondary rated current turns ratios of the CT winding, which are used as parameters to describe the winding and are applicable to the relationship conversion between primary and secondary currents.

[0080] The process of determining the associated secondary equipment of the winding refers to determining the secondary equipment connected to this CT winding, which is represented by the defined IED name;

[0081] The determination of the phase selection of the winding is to select A, B, C, zero sequence, gap, or single phase, which indicates the corresponding phase winding under this CT winding;

[0082] The process of determining the associated sampling channel for the winding involves selecting the sampling channel signal path in the model file corresponding to the IED.

[0083] Selecting the windings allows for precise association between the CT windings and the sampling channels of secondary equipment. Combined with the definition of parameters such as CT ratio and polarity, it can assist in defining common channels for different devices. For example, Figure 8 In this system, the sampling channels of bus tie 1 protection, bus protection 1, and fault recorder acquisition unit can all be associated with phases A, B, and C of winding 1 of bus tie 1 CT. Based on this association, the recorder can automatically select the recording channels of bus tie 1 protection, bus tie 1 branch of bus protection 1, and bus tie 1 recording channel of fault recorder acquisition unit as a group of homogeneous channels to realize transient homogeneous comparison and steady-state homogeneous comparison applications.

[0084] Step 2: Set the geometry of the CT, and use the symbol * to indicate the geometric polarity of the CT; for example... Figure 3As shown, the geometry of a CT consists of two basic primitives: circles and the symbol *. Connection points are defined on both sides of the circle. Several circles represent the number of windings in the CT. The * symbol is placed outside the circle on one side to indicate polarity. When the CT is displayed, it can be either a summary display or a full winding display. The polarity end is also displayed simultaneously, with the symbol * representing the geometric polarity end of the CT. This polarity end is defined by the polarity end parameter in the CT parameters. The default layout of the CT primitives is vertically connected. When the polarity end parameter is 1, the symbol * is on the upper left side of the CT primitive. When the polarity end parameter is 2, the symbol * is on the lower left side of the CT primitive. The vertical and horizontal layouts of the CT primitives in the graphic are obtained by rotating the primitives.

[0085] Step 3: Set up the application logic model of CT to describe the CT polarity in the logical relationship.

[0086] The application logic model of CT describes the logical attributes of CT in different application scenarios. When applying CT, the polarity parameters provided by the design side are based on geometric relationships, while the application side needs to obtain the logical relationships of the polarity parameters. By selecting a CT, parameters such as change ratio, associated equipment, and polarity can be modified. Other applications can extract the parameters of this CT to implement related applications.

[0087] In specific CT applications, the instantiation algorithm of CT polarity parameters of associated secondary equipment is involved. In terms of interaction, in order to minimize the difficulty of inputting polarity parameters, the provided polarity parameters are based on geometric relationships, while the application side needs to obtain the logical relationship of the polarity parameters.

[0088] The connection relationships are described based on the main wiring diagram, specifically as follows: Figure 3 , Figure 4 , Figure 8 As shown, all diagrams, based on the main wiring diagram format, fully or partially describe the CT, its polarity, winding quantity, and connection relationships with other primary equipment. Typically, Figure 4 The text describes #1CT as having a 500kV busbar group 1 connected to the left and a 500kV circuit breaker bay 1 connected to the right, with the polarity terminal on the left side of the CT image.

[0089] Define the near-end and far-end relationship between the CT polarity terminal and the target bay (the bay where the target secondary equipment is located). Any bay contains a circuit breaker or main equipment (including main transformers, lines, capacitors, reactors, busbars, etc.). If a circuit breaker is present, the circuit breaker is used as the main graphic element of the bay (e.g., circuit breaker bay, double busbar line bay). If only main equipment is present (e.g., 3 / 2 line bay, ordinary busbar bay), the main equipment is used as the main graphic element. The following two geometric logical relationships exist between the main graphic element of any bay and any CT:

[0090] The polar end of a CT image is located at the proximal end of the main image element; the polar end of a CT image element is located at the distal end of the main image element.

[0091] The above logical relationships can be extracted through the topological relationships described in the main wiring diagram. Specifically, when describing the topological relationships of the graphics, the lower left corner of the global graphics is taken as the zero point coordinate, and the coordinates of the center point of the main graphic element (x1, y1), the center point coordinates of the CT coil or coil group (x2, y2), and the coordinates of the CT polarity symbol * (x3, y3) are taken. The distance l1 between the main graphic element and the polarity symbol * and the distance l2 between the main graphic element and the center point of the CT coil are calculated respectively.

[0092]

[0093] When l1 is less than l2, the polar end of CT is at the proximal end of the main image element; when l1 is greater than l2, the polar end of CT is at the distal end of the main image element.

[0094] The following algorithm describes the polarity logical relationship between main primitives with associated intervals and CTs:

[0095] The main image element of the interval is directly connected to the polar end of the CT, and the polar end of the CT is at the proximal end of the main image element.

[0096] The main image element of the interval is directly connected to the non-polar end of the CT (the opposite side of the polar end of the CT), and the polar end of the CT is at the far end of the main image element.

[0097] The main image element of the interval is connected to the polar end of the CT image element through other image elements, and the polar end of the CT image element is located at the proximal end of the main image element.

[0098] The main image element of the interval is connected to the non-polar end of the CT through other image elements, and the polar end of the CT is at the far end of the main image element.

[0099] If the main image element of the interval is connected to the CT polar end and the CT non-polar end through other image elements, the connection corresponding to the side with the fewer image elements is the effective connection. When the effective connection side is the CT polar end, the CT polar end is at the proximal end of the main image element. When the effective connection side is the CT non-polar end, the CT polar end is at the distal end of the main image element.

[0100] For bus bays, in addition to knowing the polarity relationship between the external CT and the busbar according to the above algorithm, it is also necessary to know the polarity relationship between the CTs between busbars (such as the CTs in bus tie, bus branch, and 3 / 2 connection circuit breaker bays) relative to the busbars on both sides. Based on the CT definition, the concepts of large and small busbars are introduced, and the following two logical relationships exist:

[0101] The polarity of the CT is on the small busbar side; the polarity of the CT is on the large busbar side.

[0102] The above logical relationship is obtained through the following method:

[0103] Method 1: Set an additional parameter for the CT, namely the polarity bus number in the CT parameters mentioned above. This logical result can be obtained by setting the polarity of the CT to the small or large bus side, without the need for complex logical operations.

[0104] Method 2: Determine the bus number of the nearest busbar on both sides of the CT (the busbar number depends on the busbar definition, such as 1, 2, and 3 for busbar 1, busbar 2, and busbar 3 respectively), determine the large busbar and the small busbar, select the small busbar, calculate the distance l1 between the center point of the main graphic element of the small busbar and the polarity end symbol, and the distance l2 between the center point of the main graphic element and the center point of the CT winding, compare the two. When l1 is less than l2, the polarity end of the CT is on the small busbar side; when l1 is greater than l2, the polarity end of the CT is on the large busbar side.

[0105] Based on the above two logical relationships, the polarity parameters of the corresponding secondary devices can be effectively generated.

[0106] Step 4: Based on the configured CT geometry and logic model, implement automatic setting of IED polarity parameters and application of homogeneous sampling channel configuration; including the following steps:

[0107] Step 4.1: Obtain Strategy 1: Arbitrary Interval Protection. There is a CT polarity parameter that needs to be set. Based on this parameter, determine the SV virtual circuit automatic configuration strategy with positive and negative virtual terminals. First, based on the attribute information of the defined CT object, determine the target CT in the main wiring diagram. Based on the algorithm, obtain the near end and far end relationship between the polarity terminal of the CT and the main graphic element of this interval. If the result is near end, the corresponding parameter is 0, that is, the reverse virtual terminal is pulled. If the result is far end, the corresponding parameter is 1, that is, the positive virtual terminal is pulled.

[0108] Step 4.2: Obtain Strategy 2: Based on the algorithm, obtain the relationship between the polarity end of the CT and the main primitive and the proximal and distal ends of the main primitive. For any result that is proximal, the corresponding parameter is 1, that is, pull the positive virtual terminal. For any result that is distal, the corresponding parameter is 0, that is, pull the negative virtual terminal.

[0109] Step 4.3: Store Strategy 1 and Strategy 2 in the application's tools along with the specific type of IED, and generate different strategies for different types of IEDs;

[0110] Step 4.4: For the bus tie bay, determine the CT polarity strategy 3: When the bus number of the CT polarity terminal of the bus tie bay is small, the bus protection selects the CT polarity parameter as positive, that is, selects the positive virtual terminal of the bus tie bay SV.

[0111] Step 4.5: Automatically select and configure the positive or negative virtual terminals of the bus tie bay for bus protection based on strategy 3;

[0112] Step 4.6: Determine CT polarity strategy 4: When the bus number of the CT polarity terminal of the bus tie bay is large, the bus protection selects the CT polarity parameter as positive, that is, selects the SV (positive) virtual terminal of the bus tie bay.

[0113] Step 4.7: Based on strategy 1, strategy 2, strategy 3, and strategy 4, automatically generate the polarity parameters.

[0114] The following examples of IEDs with CT polarity applications further illustrate the specific application methods. It should be noted that the corresponding examples are only for the purpose of more conveniently illustrating the specific implementation process of the present invention, and should not be construed as limiting the scope of the problems that the present invention can solve.

[0115] Example 1: 3 / 2 wiring protection

[0116] The 3 / 2 connection line protection collects the interval current of the circuit breakers on both sides, which serves as the protection current for the side circuit breaker and the interrupted circuit breaker. Figure 4 As shown, the current of 500kV line bay 1 needs to be collected from 500kV circuit breaker bay 1 and 500kV circuit breaker bay 2 as the protection current of the side circuit breaker and the protection current of the circuit breaker of this line.

[0117] SV receiver virtual terminal for 3 / 2 wiring protection, such as Figure 5 When the protection current of the circuit breaker is collected, there are two sets of receiving virtual terminals on the receiving side, labeled as (positive) and (negative) respectively. At this time, it is necessary to automatically determine the virtual terminal to be used according to the polarity of the circuit breaker CT.

[0118] Firstly based on Figure 2 The definition of CT allows #1CT, #4CT to be associated with 500kV line bay 1.

[0119] In fact, under the known 3 / 2 wiring configuration, to ensure that the protection range of the line protection covers the circuit breakers on both sides, if multiple sets of selectable CTs exist for the line protection, the CT on the other side of the circuit breaker connected to the line is fixed. Figure 4 Given the #1CT and #4CT in the diagram, under the known 3 / 2 wiring configuration, the associated CT of the line bay can be automatically determined by adding the following algorithm: when both sides of the circuit breaker on both sides of the line have directly connected CTs, the CT on the other side of the circuit breaker connecting the line is taken as the associated CT; when both sides of the circuit breaker on both sides of the line have only one set of directly connected CTs, the CT is taken as the associated CT.

[0120] After the association is completed, the polarity parameters of the CT scanner are directly defined in the diagram based on the actual polarity of each CT scan, such as... Figure 4Assuming that the polarity of CT has been defined based on the actual installation polarity, the polarity ends of #1CT, #2CT, and #3CT are on the left side of the CT element in the figure, and the polarity end of #4CT is on the right side of the CT element in the figure.

[0121] Based on the aforementioned connection relationship between the main graphic element and the CT graphic element polarity, it can be determined that the polarity terminals of #1CT and #4CT are at the far end of the main graphic element of the 500kV line bay. For a 3 / 2 connection line bay, according to the design specifications, the positive polarity terminal of the line protection is the polarity terminal of the CT furthest from the line bay. Therefore, it can be concluded that... Figure 4 Under the corresponding CT configuration, the circuit breaker current of the 500kV line bay 1 should be connected to the SV receiving virtual terminal marked (positive).

[0122] assumed Figure 4 Each circuit breaker bay has only one CT, namely #1CT and #3CT. According to the above algorithm, 500kV line bay 1 is fixedly associated with #1CT and #3CT. Further, it is found that the polarity end of #1CT is at the far end of the main element of 500kV line bay 1, and the polarity end of #3CT is at the near end of the main element of 500kV line bay 1. According to the design specification that the positive polarity end of the 3 / 2 connection line protection is the polarity end of the CT far away from the line bay, it can be known that the circuit breaker current of 500kV line bay 1 should be pulled to the SV receiving virtual terminal marked (reverse).

[0123] Obviously, the short lead protection and main transformer protection rules for dual switches are the same as those for the aforementioned line protection.

[0124] The above strategy can be extended to cover the protection of any non-busbar bay.

[0125] For arbitrary interval protection, assuming there is a CT polarity parameter that needs to be set, the SV virtual circuit automatic configuration strategy is determined based on the parameter and the definition of (positive) and (reverse) virtual terminals. First, based on the attribute information of the defined CT object, the target CT in the main wiring diagram is determined. Based on the algorithm, the near end and far end relationship between the polarity terminal of the CT and the main graphic element of this interval is obtained. If the result is near end, the corresponding parameter is 0, that is, pull (reverse) virtual terminal. If the result is far end, the corresponding parameter is 1, that is, pull (positive) virtual terminal.

[0126] Correspondingly, there is also a reverse strategy to the above strategy, that is, the results are reversed. For any result that is near the end, the corresponding parameter is 1, that is, pull the (positive) virtual terminal. For any result that is far the end, the corresponding parameter is 0, that is, pull the (negative) virtual terminal.

[0127] The two logics mentioned above are designed as a single parameter in the application implementation, defined as CT polarity strategy 1 and 2. This can be stored in the application tool along with a specific type of IED. Different strategies will be applied for different types of IEDs. For example, strategy 1 is selected for line protection and main transformer protection, while strategy 2 is selected for bus protection. This allows the tool to automatically select and configure the (positive) and (negative) virtual terminals after defining the CT elements and their polarities based on the geometric relationship of the main wiring diagram.

[0128] Example 2: 3 / 2 busbar protection

[0129] like Figure 6 All branch current SV receiving virtual terminals of the 3 / 2 busbar protection have (positive) and (reverse) virtual terminal selection. Following the implementation process of Example 1 above, with... Figure 4 Taking the protection of bus I as an example, its associated CT is #1CT. The positional relationship between the polarity terminal of its main graphic element and #1CT is that the polarity terminal of #1CT is near the end of bus I. According to the bus protection CT polarity selection strategy 2 specified in Example 1, that is, if the result is near the end, the corresponding parameter is 1, that is, pull the (positive) virtual terminal; if the result is far the end, the corresponding parameter is 0, that is, pull the (reverse) virtual terminal. The above strategy automatically realizes the automatic selection and configuration of the (positive) and (reverse) virtual terminals of the bus protection.

[0130] by Figure 4 Taking the protection of the II bus as an example, its associated CT is #4CT. The positional relationship between its main graphic element and the polarity end of #4CT is that the polarity end of #4CT is near the II bus. Similarly, the II bus protection selects CT polarity strategy 2, that is, for any result that is near the end, the corresponding parameter is 1, that is, pull (positive) virtual terminal.

[0131] Example 3: Double busbar double-tap busbar protection

[0132] like Figure 7 The bus tie, section 1, and section 2 of the double busbar protection system have (positive) and (reverse) virtual terminals for selection.

[0133] like Figure 8 In the double busbar double branch connection configuration, busbar protection 1 protects 1M and 2M, and busbar protection 2 protects 3M and 4M. The bus tie and the section in the figure are only configured with a single CT, and the polarity of the CT is configured according to the actual CT installation as shown in the figure.

[0134] Since the bus joint exists inside the busbar, the polarity end description needs to be implemented according to the definition rules of the CT polarity end busbar number. In the figure, the polarity end busbar numbers of the two bus joint CTs are both small numbers.

[0135] If the segment exists outside the busbar, the polarity end needs to be described based on the CT polarity end and the near end and far end of the main equipment on the busbar. In the figure, the polarity ends of the two segments are near the busbar relative to 1M and 2M, and far from the busbar relative to 3M and 4M.

[0136] Based on CT polarity strategy 2 in Example 1, it can be seen that bus protection 1 should pull the (positive) virtual terminals of section 1 and section 2, and bus protection 2 should pull the (reverse) virtual terminals of section 1 and section 2, so that the automatic selection and configuration of the (positive) and (reverse) virtual terminals of the bus protection can still be correctly realized.

[0137] For the bus tie bay, define CT polarity strategy 3, which stipulates that when the bus number of the CT polarity terminal of the bus tie bay is small, the bus protection selects the CT polarity parameter as positive, that is, selects the SV (positive) virtual terminal of the bus tie bay. Then, the automatic selection and configuration of the (positive) and (reverse) virtual terminals of the bus tie bay can also be realized automatically based on strategy 3.

[0138] To ensure the integrity of the strategy and to accommodate special methods, for the bus tie bay, CT polarity strategy 4 is defined, which stipulates that when the bus number of the CT polarity terminal of the bus tie bay is large, the bus protection selects the CT polarity parameter as positive, that is, selects the SV (positive) virtual terminal of the bus tie bay.

[0139] Extending this further, the compatibility of the above examples can be easily verified for any other method. For example, in the case of internal bridge connection and expanded internal bridge connection, the main transformer protection also has the problem of selecting (positive) and (reverse) virtual terminals for the current sampling circuit of the segmented bay. Applying the CT polarity selection strategy 1 for general non-busbar bays described in Example 1, that is, if the CT polarity is near the end, the main transformer protection pulls the (reverse) virtual terminal, and if the CT polarity is far the end, the main transformer protection pulls the (positive) virtual terminal, which conforms to the design specifications of the bridge current virtual terminal of the main transformer protection under the internal bridge connection and expanded internal bridge connection methods.

[0140] In fact, the number of protections with defined polarities in engineering is limited. Based on the above strategy, the polarity parameters can be automatically generated.

[0141] Specifically, the polarity definitions of the internal logic of some protection systems may differ. For example, some bus protection systems fix the positive polarity terminal of the bus tie on the large bus side, pulling the (positive) virtual terminal of the internal virtual terminal. In this case, it is only necessary to simply adjust to CT polarity strategy 4 to quickly achieve adaptation. Furthermore, it is also possible to combine the information of specific differentiated equipment manufacturers to solidify the selection of CT polarity strategy for the corresponding manufacturer's equipment.

[0142] Through the above facts and specific embodiments, it is fully demonstrated that the CT element definition and application strategy proposed in this invention can effectively realize the automatic configuration of virtual terminals of IED devices with (positive) and (negative) defined virtual terminals in intelligent substations.

[0143] The foregoing has provided a detailed description of the embodiments of the present invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of the present invention; furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for setting CT elements without configuration in substations, characterized in that, Includes the following steps: Step 1: Set the attribute parameters of the CT, including CT parameters and winding parameters. The CT parameters include scheduling name, associated interval, number of windings, polarity end, and polarity end bus number. The winding parameters include winding selection, type, transformation ratio, associated secondary equipment, phase selection, and associated sampling channel. Step 2: Set the geometry of the CT and use the symbol * to indicate the geometric polarity of the CT; Step 3: Set up the application logic model for CT to describe the CT polarity in logical relationships; Step 4: Based on the set CT geometry and logic model, realize the automatic setting of IED polarity parameters and the application of sampling channel homogeneous configuration.

2. The CT element setting method adapted to substations without configuration according to claim 1, characterized in that: Step 1 describes setting the CT attribute parameters, and the specific operation method includes the following steps: Step 1.1: Set CT parameters, including: Step 1.11: Determine the scheduling name: The scheduling side issues a name for this CT, which is used as the globally unique name of this CT; Step 1.12: Determine the associated interval: Associate the intervals defined in the main wiring diagram and use them as the application scope description of this CT; Step 1.13: Determine the number of windings: Obtain or input the number of windings present in this CT, which will be used as a description of the CT's ability to support external devices; Step 1.14: Determine the polarity end: Define the polarity end of this CT, with enumerated values ​​including 1 and 2, representing the polarity end on both sides of the CT, respectively; Step 1.15: Determine the polarity bus number: This indicates the bus number connected to the polarity end of this CT. Enumerated values ​​include none, large number, and small number. Step 1.2: Set the winding parameters, including: Step 1.21: Select the winding: Select a specific winding, and after selection, determine the winding type, turns ratio, associated secondary equipment, phase selection, and associated sampling channel, and use it as the self-description and external relationship description of this winding.

3. The CT element setting method adapted to substations without configuration according to claim 1, characterized in that: Step 1.21, which involves determining the winding type, turns ratio, associated secondary equipment, phase selection, and associated sampling channel, specifically includes: Determining the type of the winding means determining the specification type of this CT winding and using it as the specification description of this winding. Determining the turns ratio of the winding refers to determining the primary and secondary rated current turns ratios of the CT winding, which are used as parameters to describe the winding and are applicable to the relationship conversion between primary and secondary currents. The process of determining the associated secondary equipment of the winding refers to determining the secondary equipment connected to this CT winding, which is represented by the defined IED name; The determination of the phase selection of the winding is to select A, B, C, zero sequence, gap, or single phase, which indicates the corresponding phase winding under this CT winding; The process of determining the associated sampling channel for the winding involves selecting the sampling channel signal path in the model file corresponding to the IED.

4. The CT element setting method adapted to substations without configuration according to claim 1, characterized in that: In step 2, the geometry of the CT consists of two basic primitives: circles and the symbol *. Connection points are defined on both sides of the circle. Several circles represent the number of windings in the CT. The * symbol is placed outside the circle on one side to indicate polarity. When the CT is displayed, it can be either a summary display or a full winding display. The polarity end is also displayed simultaneously, with the symbol * representing the geometric polarity end of the CT. This polarity end is defined by the polarity end parameter in the CT parameters. The default layout of the CT primitives is vertically connected. When the polarity end parameter is 1, the symbol * is on the upper left side of the CT primitive. When the polarity end parameter is 2, the symbol * is on the lower left side of the CT primitive. The vertical and horizontal layouts of the CT primitives in the graphic are obtained by rotating the primitives.

5. A method for setting CT elements in a substation without configuration, as described in claim 1, characterized in that: The CT application logic model described in step 3 describes the logical attributes of CT in different application scenarios; when applying CT, the polarity parameters provided by the design side are based on geometric relationships, while the application side needs to obtain the logical relationships of the polarity parameters. Based on the main wiring diagram, the connection relationships are described, and the near-end and far-end relationships between the CT polarity terminals and the target bay are defined. Any bay contains either a circuit breaker or a main device. If a circuit breaker is present, the circuit breaker is used as the main graphic element of the bay. If only the main device is present, the main device is used as the main graphic element. The following two geometric logical relationships exist between the main graphic element of any bay and any CT: The polarity of a CT image is at the proximal end of the main image element; the polarity of a CT image is at the distal end of the main image element. For bus bays, in addition to obtaining the polarity proximal-distal relationship between the CT and the bus, based on the CT definition, the concepts of large and small bus are further introduced, resulting in the following two logical relationships: The polarity of the CT is on the small busbar side; the polarity of the CT is on the large busbar side.

6. A method for setting CT elements in a substation without configuration, as described in claim 5, characterized in that: The logical implementation of the CT application logic model includes the following specific details: For non-busbar intervals: calculate the distance l1 between the center point of the main graphic element and the polarity end symbol, and the distance l2 between the center point of the main graphic element and the center point of the CT winding, respectively. Compare the two. When l1 is less than l2, the polarity end of the CT is near the main graphic element. When l1 is greater than l2, the polarity end of the CT is far from the main graphic element. For bus bays: Method 1: Setting the polarity of the specified CT on the small or large busbar side to obtain the logical result, without the need for complex logical operations; Method 2: Determine the bus number of the nearest busbar connecting both sides of the CT. The bus number is defined according to the busbar, such as the bus numbers of busbar 1, busbar 2, and busbar 3 being 1, 2, and 3 respectively. Determine the large busbar and the small busbar, select the small busbar, and calculate the distance l1 between the center point of the main graphic element of the small busbar and the polarity end symbol, and the distance l2 between the center point of the main graphic element and the center point of the CT winding. Compare the two. When l1 is less than l2, the polarity end of the CT is on the small busbar side; when l1 is greater than l2, the polarity end of the CT is on the large busbar side.

7. A method for setting CT elements in a substation without configuration, as described in claim 1, is characterized in that: Step 4, which describes the automatic setting of IED polarity parameters based on the configured CT geometry and logic model, includes the following steps: Step 4.1: Obtain Strategy 1: Arbitrary Interval Protection. There is a CT polarity parameter that needs to be set. Based on this parameter, determine the SV virtual circuit automatic configuration strategy with positive and negative virtual terminals. First, based on the attribute information of the defined CT object, determine the target CT in the main wiring diagram. Based on the algorithm, obtain the near end and far end relationship between the polarity terminal of the CT and the main graphic element of this interval. If the result is near end, the corresponding parameter is 0, that is, the reverse virtual terminal is pulled. If the result is far end, the corresponding parameter is 1, that is, the positive virtual terminal is pulled. Step 4.2: Obtain Strategy 2: Based on the algorithm, obtain the relationship between the polarity end of the CT and the main primitive and the proximal and distal ends of the main primitive. For any result that is proximal, the corresponding parameter is 1, that is, pull the positive virtual terminal. For any result that is distal, the corresponding parameter is 0, that is, pull the negative virtual terminal. Step 4.3: Store Strategy 1 and Strategy 2 in the application's tools along with the specific type of IED, and generate different strategies for different types of IEDs; Step 4.4: For the bus tie bay, determine the CT polarity strategy 3: When the bus number of the CT polarity terminal of the bus tie bay is small, the bus protection selects the CT polarity parameter as positive, that is, selects the positive virtual terminal of the bus tie bay SV. Step 4.5: Automatically select and configure the positive or negative virtual terminals of the bus tie bay for bus protection based on strategy 3; Step 4.6: Determine CT polarity strategy 4: When the bus number of the CT polarity terminal of the bus tie bay is large, the bus protection selects the CT polarity parameter as positive, that is, selects the SV (positive) virtual terminal of the bus tie bay. Step 4.7: Based on strategy 1, strategy 2, strategy 3, and strategy 4, automatically generate the polarity parameters.

8. A method for setting CT elements in a substation without configuration, as described in claim 1, characterized in that: The sampling channel homogeneous configuration described in step 4 specifically includes: defining the winding separately, meticulously realizing the association between the CT winding and the sampling channels of the secondary equipment, combining the definition of CT ratio and polarity to assist in defining homogeneous channels for different equipment in the CT winding, associating the sampling channels of different equipment with the same winding of the target CT, and automatically selecting the waveform recording channels of all equipment as a group of homogeneous channels based on this association, thus realizing the normalized association description of the sampling channels of all associated equipment from the source.

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