A Logic Configuration Method for Automatic Voltage Control in Hydropower Plants

Abstract

The present invention discloses a hydropower plant automatic voltage control logic configuration method, which belongs to the field of hydropower plant automatic control technology. The main process framework of the hydropower plant AVC logic configuration at the business logic layer can be divided into three stages. The first stage includes submodules such as the plant-wide reactive power / voltage setting mode submodule, the single-machine AVC on / off condition judgment submodule, and the plant-wide AVC on / off condition judgment submodule, which are used to judge whether the plant-wide AVC is in operation and determine the plant-wide reactive power / voltage setting mode; the second stage includes submodules such as the input fault tolerance check submodule, the reactive power setting control mode submodule, and the voltage setting control mode submodule, which are used to calculate the plant-wide AVC reactive power distribution value Q_AVCSET; the third stage includes submodules such as the equal power factor distribution submodule, the reactive capacity proportional distribution submodule, and the similar adjustment margin distribution submodule, which are used to calculate the AVC distribution value of each unit in operation, and when the AVC is in closed-loop regulation mode, the AVC distribution value is distributed to each unit.

Description

Technical Field

[0001] The invention belongs to the technical field of hydropower plant automatic control, and in particular relates to a hydropower plant automatic voltage control logic configuration method. Background Art

[0002] Automatic Voltage Control (AVC) is a technology that automatically controls a hydropower plant's bus voltage or overall reactive power according to predetermined conditions and requirements. While ensuring safe unit operation, it provides fully utilized reactive power to the system, reducing power losses. The hydropower plant's AVC substation system receives plant-wide control targets (such as the plant's high-voltage bus voltage and total reactive power) from the AVC master station system and distributes them to each unit according to control strategies (voltage curves, constant bus voltage, and constant reactive power). By adjusting generator reactive output to achieve plant-wide target control values, it achieves automatic voltage and reactive power control for multiple units across the plant.

[0003] In hydropower plant monitoring systems, AVC configuration logic typically exists as function blocks within the monitoring system's host computer program. The AVC configuration logic program structure can be divided into an interface style layer, a business logic layer, and a data acquisition layer. The interface style layer implements human-computer interface interaction, the data acquisition layer facilitates data interaction with the database, and the business logic layer serves as the core of AVC functionality. The key lies in achieving simplicity, efficiency, maintainability, scalability, and reusability through the rational design of the logic configuration's overall structure, functional modules, data structures, algorithms, and interfaces. Summary of the Invention

[0004] The present invention provides a method for configuring the automatic voltage control logic of a hydropower plant to solve the technical problems in the prior art, such as the massive multi-modal data and diverse queries causing data index expansion, the inability to effectively support cross-type retrieval of multi-modal data, and the difficulty in meeting the real-time requirements of big data retrieval services.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for configuring automatic voltage control logic in a hydropower plant comprises the following steps:

[0007] Step 1: Receive external input instructions and determine the plant-wide AVC given control mode according to the external input instructions. The plant-wide AVC given control mode includes reactive power given control mode and voltage given control mode;

[0008] Step 2: Determine the selection of the external input command to determine whether the stand-alone AVC is in the stand-alone AVC input state or the stand-alone AVC exit state;

[0009] Step 3: Determine whether the selection of the external input command and the AVC start / stop status of the single machine meet the plant-wide AVC start / stop conditions, and after determination, determine whether the plant-wide AVC start / stop status is plant-wide AVC start / stop;

[0010] Step 4: If the plant-wide AVC on / off status is determined to be the plant-wide AVC on / off status in step 3, determine whether the plant-wide AVC given control mode is the reactive power given control mode according to the plant-wide AVC given control mode in step 1. If the plant-wide AVC given control mode is the reactive power given control mode, calculate the plant-wide reactive power given distribution value; otherwise, if the plant-wide AVC given control mode is the voltage given control mode, calculate the plant-wide voltage given distribution value;

[0011] Step 5: If the AVC status of the entire plant is determined to be not in use in step 3, re-enter the command and repeat steps 1 to 3;

[0012] Step 6: Calculate the AVC distribution value based on the plant-wide AVC reactive power distribution value in step 4;

[0013] Step 7: Determine whether AVC is closed-loop regulation based on external input instructions. If it is closed-loop regulation, the AVC of each unit is issued according to the AVC allocation value and the process is ended. If it is not closed-loop regulation, the process is ended directly.

[0014] In step 1, to determine the AVC given control mode for the entire plant, it is necessary to first determine the plant-wide given control mode based on external input instructions. If the curve mode is adopted, the control right of the entire plant AVC belongs to the power plant, and the plant-wide AVC given control mode is the plant-wide voltage given control mode. If the fixed value mode is adopted, it is determined based on external input whether the control right of AVC belongs to the power plant, dispatching or centralized control, and whether the reactive power given control mode or the voltage given control mode is adopted is determined based on external input. If neither the curve mode nor the fixed value mode is adopted, the external input instruction is re-performed to select whether to adopt the curve mode.

[0015] When the AVC control right belongs to the power plant, regulation or centralized control, the external input instructions are used to determine whether the AVC given control mode of the entire plant is the reactive power given control mode or the voltage given control mode. If neither is the case, the AVC given control mode of the entire plant is re-determined through external instruction input; when the AVC control right does not belong to the power plant, regulation or centralized control, the AVC control right is determined through the external instruction input center.

[0016] If the AVC control right is for the power plant and in the reactive power setting control mode, the reactive power set value of the whole plant is assigned to the value set on the AVC screen by the power plant operator; if the AVC control right is for centralized control and in the reactive power setting control mode, the reactive power set value of the whole plant is assigned to the value sent by the centralized control through telecontrol communication; if the AVC control right is for dispatching and in the reactive power setting control mode, the reactive power set value of the whole plant is assigned to the value sent by the dispatching through telecontrol communication; if the AVC control right is for the power plant and in the voltage setting control mode, the bus voltage set value is assigned to the value set on the AVC screen by the power plant operator; if the AVC control right is for dispatching and in the voltage setting control mode, the bus voltage set value is assigned to the value sent by the dispatching through telecontrol communication; if the AVC control right is for centralized control and in the voltage setting control mode, the bus voltage set value is assigned to the value sent by the centralized control through telecontrol communication.

[0017] If the whole plant setting mode is reactive setting control mode, the whole plant AVC reactive power distribution of reactive setting mode is calculated by reactive setting control mode. ,in, For: AVC reactive power distribution of the whole plant, =: The reactive power setting value of the whole plant, It is the sum of the reactive power values ​​of the units that are not put into AVC.

[0018] If the whole plant setting mode is reactive setting control mode, it is necessary to check whether the whole plant reactive setting value is within the upper and lower limits of the whole plant reactive setting value. When the whole plant reactive setting value is within the upper and lower limits, it is a valid setting value. Otherwise, it will not be set and an error will be reported. The upper limit calculation method of the whole plant reactive setting value is: , The maximum reactive power of the units that have been put into operation under the current operating conditions is n, which is the number of units put into operation under the AVC. The calculation method for the lower limit of the reactive power setting value of the whole plant is: ,in, It is the minimum reactive power sum of the AVC units under the current operating conditions, and n is the number of AVC units put into operation.

[0019] If the plant-wide given mode is the voltage given control method, the plant-wide AVC reactive power distribution value of the reactive power given mode is calculated using the voltage given control method. When the system bus voltage is within the normal voltage value range, the normal dispatch coefficient is used for calculation:

[0020]

[0021] (2) When the system bus voltage exceeds the normal voltage range but does not exceed the upper and lower limits of the fault voltage, the emergency dispatch coefficient is used for calculation:

[0022]

[0023] (3) When the system bus voltage exceeds the upper and lower limits of the fault voltage, the whole plant AVC is exited;

[0024] in, = AVC reactive power distribution value of the whole plant when the system bus voltage is within the normal voltage range. The AVC reactive power distribution value of the whole plant when the system bus voltage exceeds the normal voltage range but does not exceed the upper and lower limits of the fault voltage. = The sum of the reactive power values ​​of the units that have been put into AVC, is: normal voltage regulation coefficient, is: emergency dispatch coefficient, is: the deviation between the actual bus voltage and the bus voltage setting value, Emergency pressure regulation coefficient.

[0025] In step six, the allocation of AVC is divided into three allocation methods: equal power factor allocation, reactive capacity proportional allocation, and similar scheduling margin allocation. The AVC allocation method is selected according to the external input instruction.

[0026] First, determine whether the allocation is based on equal power factors. If so, AVC will be allocated based on equal power factors. Otherwise, determine whether the allocation is based on proportional reactive capacity. If so, AVC will be allocated based on proportional reactive capacity. Otherwise, determine whether the allocation is based on similar adjustment margins. If so, AVC will be allocated based on similar adjustment margins. If none of the three allocation methods are used, re-enter the command to determine the three AVC allocation methods.

[0027] When AVC performs equal power factor allocation, the method for calculating the allocation value of each AVC is as follows: When AVC distributes reactive capacity proportionally, the method for calculating the distribution value of each AVC is as follows: When AVC performs similar scheduling margin allocation, the method for calculating the allocation value of each AVC is as follows: ;in, =Equal power distribution value for each AVC, The reactive capacity of each AVC is proportionally distributed. is: the similar dispatch margin allocation value of each AVC, n is the number of AVC units put into operation, is the current active power value of the AVC units that have been put into use, is the maximum reactive capacity of the AVC units that have been put into operation, is the current reactive power value, and are given externally.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] This invention discloses a method for configuring the automatic voltage control logic of a hydropower plant. This method employs a modular design, with each module having a single responsibility and adhering to the principles of high cohesion and low coupling. High cohesion means that the elements within the module are closely connected, so that modifications within the module will not affect external callers or dependents, thereby reducing maintenance costs and time. Low coupling reduces the connections between modules, helping to improve development efficiency.

[0030] The design of this invention adheres to the principles of interface isolation and abstraction. The modules, functions, or methods to be called are abstracted into interfaces to hide their implementation details, thereby separating the interface from the internal details. Furthermore, the number and complexity of interfaces are effectively balanced, minimizing the number of interfaces and minimizing their complexity.

[0031] The design of the present invention follows the principles of simplicity and efficiency in the design of the overall process structure, functional module definition, external interface and internal algorithm, avoids code redundancy and repetition, improves code reuse rate, and has high maintainability, scalability and reusability. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of the main flow of the automatic voltage control (AVC) logic configuration of a hydropower plant according to the present invention;

[0033] Figure 2 This is a submodule flow chart of the plant-wide reactive power / voltage setting method of the present invention;

[0034] Figure 3 This is a flow chart of the stand-alone AVC on / off condition judgment submodule of the present invention;

[0035] Figure 4 This is a schematic diagram of single-stage AVC input conditions;

[0036] Figure 5 This is a schematic diagram of the automatic exit conditions for a single-stage AVC;

[0037] Figure 6 This is a flow chart of the plant-wide AVC entry and exit condition judgment submodule of the present invention;

[0038] Figure 7 This is a schematic diagram of AVC input conditions for the entire plant;

[0039] Figure 8 This is a schematic diagram of the automatic exit conditions of AVC for the entire plant;

[0040] Figure 9 This is a flow chart of the voltage setting control mode submodule of the present invention. DETAILED DESCRIPTION

[0041] In order to further understand the content of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the embodiments are only for explaining the present invention and are not intended to limit it.

[0042] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0043] See also Figure 1 ,The main process framework of the AVC logic configuration of the ,hydropower plant at the business logic layer can be divided into three stages.

[0044] The first stage includes the submodules of plant-wide reactive power / voltage setting mode submodule, single-machine AVC on / off condition judgment submodule and plant-wide AVC on / off condition judgment submodule. After the first stage of the main process starts, firstly, according to the external input instruction, the plant-wide AVC setting mode is selected as curve mode or fixed value mode, and then the plant-wide reactive power / voltage setting mode submodule is executed to select the plant-wide given control mode. Then, the single-machine AVC on / off condition judgment submodule and the plant-wide AVC on / off condition judgment submodule are executed. Figure 4 、 Figure 5 、 Figure 7 and Figure 8 The single-machine input conditions, single-machine exit conditions, whole-plant input conditions and front-end exit conditions shown in the figure are used to determine whether the whole-plant AVC is put into operation. If it is put into operation, the second stage of the main process is entered. If not, the process returns to continue executing the above three sub-modules.

[0045] The submodules included in the second stage are the input fault tolerance check submodule, the reactive power given control mode submodule, and the voltage given control mode submodule. After the second stage of the main process starts, it first determines whether it is in the reactive power given control mode. If so, it executes the input fault tolerance check submodule and the reactive power given control mode submodule in sequence. Otherwise, it continues to determine whether it is in the voltage given control mode. If so, it executes the voltage given control mode submodule. Otherwise, it returns to the beginning of the second stage. The AVC reactive power distribution value of the entire plant is calculated through the reactive power given control mode submodule or the voltage given control mode submodule. Then, enter the third stage of the main process.

[0046] The third stage includes the equal power factor allocation submodule, the reactive capacity proportional allocation submodule, and the similar adjustment margin allocation submodule. When the third stage of the main process begins, it first determines whether allocation is being performed according to the equal power factor mode. If so, the equal power factor allocation submodule is executed. Otherwise, it continues to determine whether allocation is being performed according to the reactive capacity proportional mode. If so, the reactive capacity proportional allocation submodule is executed. Otherwise, it continues to determine whether allocation is being performed according to the similar adjustment margin mode. If so, the similar adjustment margin allocation submodule is executed. Otherwise, it returns to the beginning of the third stage. After calculating the AVC allocation value for each unit in AVC using the selected reactive power allocation mode, it determines whether AVC is in closed-loop regulation. If so, the AVC allocation value for each unit is distributed and the main process ends. Otherwise, the main process ends directly.

[0047] See also Figure 2 , the whole plant reactive power / voltage setting mode sub-module flow chart, after the process starts, first determine whether it is the curve mode, if so, the AVC control right is switched to the power plant, and switched to the voltage setting control mode, the bus voltage setting value is assigned to the current value of the curve voltage, and the process ends, otherwise continue to determine whether it is the fixed value mode, if otherwise return to the beginning of the process, if yes, determine whether the AVC control right belongs to the power plant, if yes, determine whether it is the reactive power setting control mode, if yes, the whole plant reactive power setting value is assigned to the setting value on the AVC screen by the power plant operator, and the process ends, otherwise continue to determine whether it is the voltage setting control mode, if yes, the bus voltage setting value is assigned to the setting value on the AVC screen by the power plant operator, and the process ends, otherwise return to determine whether it is the reactive power setting control mode; if the AVC control right does not belong to the power plant, then continue to determine whether the AVC control right belongs to the dispatcher If it is, determine whether it is reactive power given control mode. If it is, the reactive power setting value of the whole plant is assigned to the value sent by the dispatch through remote communication, and the process ends. Otherwise, continue to determine whether it is voltage given control mode. If it is, the bus voltage setting value is assigned to the value sent by the dispatch through remote communication, and the process ends. Otherwise, return to determine whether it is reactive power given control mode; if the AVC control right does not belong to the dispatch, continue to determine whether the AVC control right belongs to the dispatch. If it is, otherwise return to determine whether the AVC control right belongs to the power plant. If it is, determine whether it is reactive power given control mode. If it is, the reactive power setting value of the whole plant is assigned to the value sent by the centralized control through remote communication, and the process ends. Otherwise, continue to determine whether it is voltage given control mode. If it is, the bus voltage setting value is assigned to the value sent by the centralized control through remote communication, and the process ends. Otherwise, return to determine whether it is reactive power given control mode.

[0048] See also Figure 3 、 Figure 4 and Figure 5As shown in the flowchart of the stand-alone AVC investment and exit condition judgment submodule, after the process starts, it is first determined whether the stand-alone AVC has been invested. If so, it continues to determine whether the stand-alone AVC automatic exit condition is met. If so, it automatically exits the stand-alone AVC and enters the end of the process. Otherwise, it continues to determine whether there is a stand-alone AVC exit instruction. If so, it exits the stand-alone AVC and enters the end of the process. Otherwise, it directly enters the end of the process. If the result of the first judgment link of the process is that the stand-alone AVC has not been invested, it continues to determine whether the stand-alone AVC investment condition is met. If so, it directly enters the end of the process. If so, it continues to determine whether there is a stand-alone AVC investment instruction. If so, it invests the stand-alone AVC and enters the end of the process. Otherwise, it directly enters the end of the process.

[0049] Among them, the conditions for single-machine AVC activation include that the unit has no accident shutdown or emergency shutdown signal, the excitation system is in automatic state or has no fault, the communication between the monitoring and excitation systems is normal, the unit is in grid-connected state, the unit reactive power measurement value is accurate, and the system bus voltage does not exceed the upper and lower limits of the fault voltage; the conditions for single-machine AVC automatic exit include that the unit has an accident shutdown or emergency shutdown signal, the excitation system is not in automatic state or has no fault, the communication between the monitoring and excitation systems is abnormal, the unit is not in grid state, the unit reactive power measurement value is inaccurate, the system bus voltage exceeds the upper and lower limits of the fault voltage, and the entire field AVC switches from activation to exit.

[0050] See also Figure 6 、 Figure 7 and Figure 8 After the process starts, it first determines whether the plant-wide AVC has been put into operation. If so, it continues to determine whether the plant-wide AVC automatic exit conditions are met. If so, it automatically exits the plant-wide AVC and ends the process. Otherwise, it continues to determine whether there is a plant-wide AVC exit instruction. If so, it exits the plant-wide AVC and ends the process. Otherwise, it directly ends the process. If the result of the first determination link of the process is that the plant-wide AVC has not been put into operation, it continues to determine whether the plant-wide AVC entry conditions are met. If so, it directly ends the process. If so, it continues to determine whether there is a plant-wide AVC entry instruction. If so, it enters the plant-wide AVC and ends the process. Otherwise, it directly ends the process.

[0051] Among them, the conditions for the activation of AVC in the entire plant include that at least one unit is activated in single-stage AVC mode, the system bus voltage does not exceed the upper and lower limits of the fault voltage, the system bus voltage has no oscillation, when the bus is combined, the voltage difference between I bus and I bus is within the allowable range, and there is no accident in the power plant; the conditions for the automatic exit of AVC in the entire plant include that no unit is activated in single-stage AVC mode, the system bus voltage exceeds the upper and lower limits of the fault voltage, the system bus voltage oscillates, when the bus is combined, the voltage difference between I bus and I bus is within the allowable range, and there is an accident in the power plant.

[0052] See also Figure 9As shown, after the process starts, it is first determined whether the system bus voltage is within the normal voltage value range. If so, the normal voltage regulation coefficient is used to calculate the AVC reactive power distribution value of the entire plant, and the process ends. Otherwise, it continues to determine whether the system bus voltage is within the upper and lower limits of the fault voltage. If so, the emergency voltage regulation coefficient is used to calculate the AVC reactive power distribution value of the entire plant, and the process ends. Otherwise, the process ends after exiting the entire plant AVC.

[0053] Based on the functional requirements and development requirements of a hydropower plant's AVC logic configuration, this embodiment proposes a hydropower plant automatic voltage control (AVC) logic configuration design scheme. Through this AVC logic configuration design scheme, the main process framework is designed, followed by the functional design of each submodule, and then the external interface and internal algorithm of each submodule are designed. The specific implementation steps are as follows:

[0054] The main process framework of a hydropower plant automatic voltage control logic configuration method can be divided into three stages.

[0055] The function of the first stage is to determine whether the whole plant AVC is in operation and to determine the reactive power / voltage setting mode of the whole plant. Figure 1 As shown in the first stage part of the figure, the sub-modules included in the first stage are the plant-wide reactive power / voltage setting mode sub-module, the single-machine AVC on / off condition judgment sub-module and the plant-wide AVC on / off condition judgment sub-module; first, the plant-wide reactive power / voltage setting mode sub-module, the single-machine AVC on / off condition judgment sub-module and the plant-wide AVC on / off condition judgment sub-module are executed in sequence, and then it is judged whether the plant-wide AVC is on. If it is on, the second stage of the main process is entered. If not, the process returns to continue executing the above three sub-module processes.

[0056] The functions, external interfaces and internal algorithm designs of the three submodules in the first phase are shown in Table 1. The plant-wide reactive power / voltage setting mode submodule determines whether to adopt the fixed value mode or the curve mode according to the external input; when the fixed value mode is adopted, the control right of AVC is determined according to the external input, and whether the reactive power setting control mode or the voltage setting control mode is adopted according to the external input; when the curve mode is adopted, the control right of AVC belongs to the power plant and the voltage setting control mode is adopted. At this time, the voltage setting control mode submodule of the second phase calculates , as shown in the internal algorithm design of the voltage reference control mode submodule in Table 2 below. The single-unit AVC on / off condition judgment submodule switches the single-unit AVC on / off status based on the single-unit AVC on / off conditions (single-unit AVC on / off conditions: the unit has no accident shutdown or emergency shutdown signal, the excitation system is in automatic mode or has no faults, the monitoring and excitation system are communicating normally, the unit is grid-connected, the unit's reactive power measurement is accurate, and the system bus voltage does not exceed the upper and lower fault voltage limits; single-unit AVC off-state conditions: the unit has an accident shutdown or emergency shutdown signal, the excitation system is not in automatic mode or has no faults, the monitoring and excitation system is communicating abnormally, the unit is not grid-connected, the unit's reactive power measurement is inaccurate, the system bus voltage exceeds the upper and lower fault voltage limits, and the plant-wide AVC is switched from on to off). According to the plant-wide AVC on-off conditions (plant-wide AVC on-off conditions: at least one unit is put into single-unit AVC mode, the system bus voltage does not exceed the upper and lower limits of the fault voltage, the system bus voltage has no oscillation, the voltage difference between bus I and bus II during combined bus operation is within the allowable range, and there is no accident in the power plant; plant-wide AVC off-off conditions: no unit is put into single-unit AVC mode, the system bus voltage exceeds the upper and lower limits of the fault voltage, the system bus voltage oscillates, the voltage difference between bus I and bus II during combined bus operation is within the allowable range, and there is an accident in the power plant), the judgment sub-module switches the plant-wide AVC on-off status according to the plant-wide AVC on-off conditions.

[0057] Table 1

[0058]

[0059] The function of the second stage is to calculate the AVC reactive power distribution value of the whole plant . The submodules included in the second stage are the input fault tolerance check submodule, the reactive power given control mode submodule and the voltage given control mode submodule. In the first stage, it is determined whether the AVC of the entire plant is in operation. After entering the second stage, it is first determined whether it is in the reactive power given control mode. If so, the input fault tolerance check submodule and the reactive power given control mode submodule are executed in sequence. Otherwise, it continues to determine whether it is in the voltage given control mode. If so, the voltage given control mode submodule is executed. Otherwise, it returns to the beginning of the second stage. After the reactive power distribution value Q_AVCSET of the entire plant AVC is calculated by the reactive power given control mode submodule or the voltage given control mode submodule, the third stage of the main process is entered. The functions, external interfaces and internal algorithm designs of the three submodules of the second stage are shown in Table 2:

[0060] Table 2

[0061]

[0062] The third stage calculates the AVC allocation value for each unit in AVC mode. When AVC is in closed-loop regulation mode, this value is distributed to each unit. The third stage includes the equal power factor allocation submodule, the reactive capacity proportional allocation submodule, and the similar adjustment margin allocation submodule. When the process enters the third stage, it first determines whether allocation is in equal power factor mode. If so, the equal power factor allocation submodule is executed. Otherwise, it determines whether allocation is in proportional reactive capacity mode. If so, the reactive capacity proportional allocation submodule is executed. Otherwise, it determines whether allocation is in similar adjustment margin mode. If so, the similar adjustment margin allocation submodule is executed. Otherwise, it returns to the beginning of the third stage. After calculating the AVC allocation value for each unit in AVC mode using the selected reactive power allocation mode, it determines whether AVC is in closed-loop regulation. If so, the AVC allocation value for each unit is distributed and the main process ends. Otherwise, the main process ends directly. The functions, external interfaces, and internal algorithm designs of the three submodules in the third stage are shown in Table 3:

[0063] Table 3

[0064]

[0065] In addition, it should be understood that although this specification describes the embodiments, not every embodiment contains only one independent technical solution. This description is for clarity only. Those skilled in the art should consider the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for the purpose of illustrating the technical concept of the present invention and cannot be used to limit the scope of protection of the present invention. Any changes made based on the technical solution in accordance with the technical concept proposed by the present invention fall within the scope of protection of the claims of the present invention.

Claims

1. A method for configuring automatic voltage control logic in a hydropower plant, characterized in that: The following steps are involved: Step 1: Receive external input instructions and determine the plant-wide AVC given control mode according to the external input instructions. The plant-wide AVC given control mode includes reactive power given control mode and voltage given control mode; Step 2: Determine the selection of the external input command and determine whether the stand-alone AVC is in the stand-alone AVC input state or the stand-alone AVC exit state; Step 3: Determine whether the selection of the external input command and the AVC start / stop status of the single machine meet the plant-wide AVC start / stop conditions, and after determination, determine whether the plant-wide AVC start / stop status is plant-wide AVC start / stop; Step 4: If the plant-wide AVC on / off status is determined to be the plant-wide AVC on / off status in step 3, determine whether the plant-wide AVC given control mode is the reactive power given control mode according to the plant-wide AVC given control mode in step 1. If the plant-wide AVC given control mode is the reactive power given control mode, calculate the plant-wide reactive power given distribution value; otherwise, if the plant-wide AVC given control mode is the voltage given control mode, calculate the plant-wide voltage given distribution value; Step 5: If the AVC status of the entire plant is determined to be not in use in step 3, re-enter the command and repeat steps 1 to 3; Step 6: Calculate the AVC distribution value based on the plant-wide AVC reactive power distribution value in step 4; Step 7: Determine whether AVC is closed-loop regulation based on external input instructions. If it is closed-loop regulation, the AVC of each unit is issued according to the AVC allocation value and the process is ended. If it is not closed-loop regulation, the process is ended directly.

2. A hydropower plant automatic voltage control logic configuration method according to claim 1, characterized in that: In the step 1, the plant-wide AVC given control mode is determined. It is necessary to first determine the plant-wide given mode according to the external input instructions. If the curve mode is adopted, the plant-wide AVC control right belongs to the power plant, and the plant-wide AVC given control mode is the plant-wide voltage given control mode. If the fixed value mode is adopted, the power plant, dispatching or centralized control right of AVC is determined according to the external input, and whether the reactive power given control mode or the voltage given control mode is adopted is determined according to the external input. If neither the curve mode nor the fixed value mode is adopted, the external input instruction is re-performed to select whether to adopt the curve mode.

3. A hydropower plant automatic voltage control logic configuration method according to claim 2, characterized in that: When the AVC control right belongs to the power plant, regulation or centralized control, the external input instructions are used to determine whether the AVC given control mode of the entire plant is the reactive power given control mode or the voltage given control mode. If neither is the case, the AVC given control mode of the entire plant is re-determined through external instruction input; when the AVC control right does not belong to the power plant, regulation or centralized control, the AVC control right is determined through the external instruction input center.

4. A hydropower plant automatic voltage control logic configuration method according to claim 3, characterized in that: If the AVC control right is for the power plant and in the reactive power setting control mode, the reactive power set value of the whole plant is assigned to the value set on the AVC screen by the power plant operator; if the AVC control right is for centralized control and in the reactive power setting control mode, the reactive power set value of the whole plant is assigned to the value sent by the centralized control through telecontrol communication; if the AVC control right is for dispatching and in the reactive power setting control mode, the reactive power set value of the whole plant is assigned to the value sent by the dispatching through telecontrol communication; if the AVC control right is for the power plant and in the voltage setting control mode, the bus voltage set value is assigned to the value set on the AVC screen by the power plant operator; if the AVC control right is for dispatching and in the voltage setting control mode, the bus voltage set value is assigned to the value sent by the dispatching through telecontrol communication; if the AVC control right is for centralized control and in the voltage setting control mode, the bus voltage set value is assigned to the value sent by the centralized control through telecontrol communication.

5. A hydropower plant automatic voltage control logic configuration method according to claim 4, characterized in that: If the whole plant setting mode is reactive setting control mode, the whole plant AVC reactive power distribution of reactive setting mode is calculated by reactive setting control mode. ,in, For: AVC reactive power distribution of the whole plant, =: The reactive power setting value of the whole plant, It is the sum of the reactive power values ​​of the units that are not put into AVC.

6. A hydropower plant automatic voltage control logic configuration method according to claim 5, characterized in that: If the whole plant setting mode is reactive setting control mode, it is necessary to check whether the whole plant reactive setting value is within the upper and lower limits of the whole plant reactive setting value. When the whole plant reactive setting value is within the upper and lower limits, it is a valid setting value. Otherwise, it will not be set and an error will be reported. The upper limit calculation method of the whole plant reactive setting value is: , The maximum reactive power of the units that have been put into operation under the current operating conditions is n, which is the number of units put into operation under the AVC. The calculation method for the lower limit of the reactive power setting value of the whole plant is: ,in, It is the minimum reactive power sum of the AVC units under the current operating conditions, and n is the number of AVC units put into operation.

7. A hydropower plant automatic voltage control logic configuration method according to claim 4, characterized in that: If the plant-wide given mode is the voltage given control method, the plant-wide AVC reactive power distribution value of the reactive power given mode is calculated using the voltage given control method. When the system bus voltage is within the normal voltage value range, the normal dispatch coefficient is used for calculation: (2) When the system bus voltage exceeds the normal voltage range but does not exceed the upper and lower limits of the fault voltage, the emergency dispatch coefficient is used for calculation: (3) When the system bus voltage exceeds the upper and lower limits of the fault voltage, the whole plant AVC is exited; in, = AVC reactive power distribution value of the whole plant when the system bus voltage is within the normal voltage range. The AVC reactive power distribution value of the whole plant when the system bus voltage exceeds the normal voltage range but does not exceed the upper and lower limits of the fault voltage. = The sum of the reactive power values ​​of the units that have been put into AVC, is: normal voltage regulation coefficient, is: emergency dispatch coefficient, is: the deviation between the actual bus voltage and the bus voltage setting value, Emergency pressure regulation coefficient.

8. A hydropower plant automatic voltage control logic configuration method according to claim 1, characterized in that: In the step six, the allocation of AVC is divided into three allocation modes: equal power factor allocation, reactive capacity proportional allocation and similar scheduling margin allocation. The AVC allocation mode is selected according to the external input instruction.

9. A hydropower plant automatic voltage control logic configuration method according to claim 8, characterized in that: First, determine whether the allocation is based on equal power factors. If so, AVC will be allocated based on equal power factors. Otherwise, determine whether the allocation is based on proportional reactive capacity. If so, AVC will be allocated based on proportional reactive capacity. Otherwise, determine whether the allocation is based on similar adjustment margins. If so, AVC will be allocated based on similar adjustment margins. If none of the three allocation methods are used, re-enter the command to determine the three AVC allocation methods.

10. A hydropower plant automatic voltage control logic configuration method according to claim 9, characterized in that: When AVC performs equal power factor allocation, the method for calculating the allocation value of each AVC is as follows: When AVC distributes reactive capacity proportionally, the method for calculating the distribution value of each AVC is as follows: When AVC performs similar scheduling margin allocation, the method for calculating the allocation value of each AVC is as follows: ;in, =Equal power distribution value for each AVC, The reactive capacity of each AVC is proportionally distributed. is: the similar dispatch margin allocation value of each AVC, n is the number of AVC units put into operation, is the current active power value of the AVC units that have been put into use, is the maximum reactive capacity of the AVC units that have been put into operation, is the current reactive power value, and are given externally.

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