Automatic voltage control logic configuration method for hydraulic power plant

Abstract

The invention discloses a hydraulic power plant automatic voltage control logic configuration method, and belongs to the technical field of hydraulic power plant automatic control, and a main process framework of hydraulic power plant AVC logic configuration in a business logic layer can be divided into three stages. Submodules included in the first stage comprise a whole-plant reactive power / voltage given mode submodule, a single-machine AVC switching condition judgment submodule and a whole-plant AVC switching condition judgment submodule and are used for judging whether whole-plant AVC is switched on or not and determining a whole-plant reactive power / voltage given mode; sub-modules included in the second stage comprise an input fault tolerance checking sub-module, a reactive given control mode sub-module and a voltage given control mode sub-module and are used for calculating a whole-plant AVC reactive distribution value QAVCSET; and submodules included in the third stage comprise an equal power factor distribution submodule, a reactive capacity proportional distribution submodule and a similar adjustment margin distribution submodule and are used for calculating an AVC distribution value of each unit which is input into the AVC, and when the AVC is in a closed-loop adjustment mode, the AVC distribution value is issued to each unit.

Description

Technical Field

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

[0002] Automatic voltage control (AVC) refers to the technology of automatically controlling the bus voltage of a hydropower plant or the reactive power of the entire power plant according to predetermined conditions and requirements. Under the condition of ensuring the safe operation of the unit, it provides the system with fully utilized reactive power and reduces the power loss of the power plant. The AVC substation system of the hydropower plant receives the plant-wide control targets (high-voltage bus voltage of the power plant, total reactive power of the entire plant, etc.) issued by the AVC master station system, and reasonably allocates them to each unit according to the control strategy (voltage curve, constant bus voltage, constant reactive power). By adjusting the reactive output of the generator, the target control value of the entire plant is achieved, and the voltage and reactive power automatic control of multiple units in the entire plant is realized.

[0003] In the monitoring system of a hydropower plant, the configuration logic of AVC generally exists in the form of functional blocks in the host computer program of the monitoring system. The program structure of the AVC configuration logic can be divided into the interface style layer, the business logic layer and the data acquisition layer. Among them, the interface style layer is responsible for realizing the interactive function of the human-computer interface, the data acquisition layer is responsible for realizing the data interaction with the database, and the business logic layer is the core of the AVC function implementation. The key lies in the reasonable design of the overall structure, functional modules, data structure, algorithm and interface of the logical configuration to achieve the simplicity, efficiency, maintainability, scalability and reusability of the logical configuration. Summary of the invention

[0004] The present invention provides a method for configuring the logic of automatic voltage control of a hydropower plant to solve the technical problems existing in the prior art that massive multi-modal data and diverse queries will cause data index expansion, cannot effectively support cross-type retrieval of multi-modal data, and are difficult to meet the real-time requirements of big data retrieval services.

[0005] In order to achieve the above object, the present invention adopts the following technical solution: A method for configuring automatic voltage control logic of a hydropower plant comprises the following steps: 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 to determine whether the single-machine AVC is in the single-machine AVC input state or the single-machine AVC exit state; Step 3: Determine whether the selection of the external input command and the AVC startup and shutdown status of the single machine meet the AVC startup and shutdown conditions of the whole plant, and after determination, determine whether the AVC startup status of the whole plant is the AVC startup of the whole plant; Step 4: If the AVC switch-on / off state of the whole plant is determined to be the AVC switch-on state of the whole plant in step 3, determine whether it is the reactive power setting control mode according to the AVC setting control mode of the whole plant in step 1. If the AVC setting control mode of the whole plant is the reactive power setting control mode, calculate the reactive power setting distribution value of the whole plant; otherwise, the AVC setting control mode of the whole plant is the voltage setting control mode, calculate the voltage setting distribution value of the whole plant; Step 5: If the AVC status of the whole plant is determined to be off in step 3, re-enter the command and repeat steps 1 to 3; Step 6: Calculate the AVC distribution value according to the plant-wide AVC reactive power distribution value in step 4; Step 7: Determine whether AVC is a closed-loop regulation according to the external input command. If it is a closed-loop regulation, the AVC of each unit is issued according to the AVC allocation value and the process is terminated. If it is not a closed-loop regulation, the process is terminated directly.

[0006] In step 1, to determine the AVC given control mode for the whole plant, it is necessary to first determine the whole plant given mode according to the external input instructions. If the curve method is adopted, the control right of the whole plant AVC belongs to the power plant, and the whole plant AVC given control mode is the whole plant voltage given control mode. If the fixed value method is adopted, it is determined according to the external input that the control right of AVC belongs to the power plant, dispatching or centralized control, and it is determined according to the external input whether the reactive power given control mode or the voltage given control mode is adopted. If neither the curve method nor the fixed value method is adopted, the external input instruction is re-performed to select whether to adopt the curve method.

[0007] When the AVC control right belongs to the power plant, regulation or centralized control, the AVC given control mode of the whole plant is judged whether it is the reactive power given control mode or the voltage given control mode according to the external input instructions. If it is neither, the AVC given control mode of the whole plant is re-judged 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 judged through the external instruction input center.

[0008] 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 set value 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 set value 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.

[0009] If the whole plant setting mode is the reactive setting control mode, the whole plant AVC reactive power distribution of the reactive setting mode is calculated by the reactive setting control mode. ,in, For: AVC reactive power distribution of the whole plant, =: reactive power setting value of the whole plant, It is: the sum of the actual reactive power values ​​of the units that are not put into AVC.

[0010] If the whole plant setting mode is the 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 able to set the value and an error will be reported; the upper limit calculation method of the whole plant reactive setting value is: , is the maximum reactive power sum of the AVC units under the current working conditions, n is the number of AVC units put into operation; the calculation method of 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.

[0011] 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 by the voltage given control mode. When the system bus voltage is within the normal voltage value range, the normal dispatch coefficient is used for calculation:

[0012] (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:

[0013] (3) When the system bus voltage exceeds the upper and lower limits of the fault voltage, the whole plant AVC is exited; in, is: the AVC reactive power distribution value of the whole plant when the system bus voltage is within the normal voltage value range, The AVC reactive power distribution value of the whole plant when the system bus voltage exceeds the normal voltage value 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 voltage regulation coefficient.

[0014] 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.

[0015] First, determine whether to allocate according to equal power factors. If so, AVC will be allocated according to equal power factors; otherwise, determine whether to allocate according to proportional reactive capacity. If so, AVC will be allocated according to proportional reactive capacity; otherwise, determine whether to allocate according to similar adjustment margin. If so, AVC will be allocated according to similar adjustment margin; if none of the three allocation methods is selected, re-enter the command to determine the three allocation methods of AVC.

[0016] 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: ;in, =Equal power allocation value for each AVC, The reactive capacity of each AVC is proportional to the distribution value. 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 use, is the current reactive power value, and are given externally.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a method for configuring the automatic voltage control logic of a hydropower plant, which adopts a modular design. Each module has a single responsibility, and the modules follow the principles of high cohesion and low coupling. High cohesion means that the elements within the module are closely connected. When modifications occur within the module, it will not affect external callers or dependents, thereby reducing maintenance costs and time; low coupling reduces the connection between modules, which helps to improve development efficiency.

[0018] The design scheme of the present invention follows the principle of interface isolation and abstraction. The modules, functions or methods to be called are abstracted into interfaces to hide the implementation details, thereby realizing the separation of interfaces from internal details; on the other hand, the number and complexity of interfaces are effectively balanced, so that the number of interfaces is as small as possible and the interface complexity is low.

[0019] 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

[0020] Figure 1 It is a schematic diagram of the main flow of the automatic voltage control (AVC) logic configuration of a hydropower plant of the present invention; Figure 2 It is a submodule flow chart of the whole plant reactive power / voltage setting mode of the present invention; Figure 3 This is a flow chart of the single-machine AVC on / off condition judgment submodule of the present invention; Figure 4 It is a schematic diagram of single-stage AVC input conditions; Figure 5 It is a schematic diagram of the automatic exit condition of single-stage AVC; Figure 6 This is a schematic diagram of the plant-wide AVC entry and exit condition judgment submodule flow of the present invention; Figure 7 This is a schematic diagram of AVC input conditions for the entire plant; Figure 8 This is a schematic diagram of the automatic exit conditions of AVC for the entire plant; Fig. 9 This is a flow chart of the voltage setting control mode submodule of the present invention. DETAILED DESCRIPTION

[0021] 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.

[0022] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0023] See also Figure 1 ,The main process framework of the AVC logic configuration of the ,hydropower plant in the business logic layer can be divided into three stages.

[0024] The first stage includes the submodules of the whole plant reactive power / voltage setting mode submodule, the single machine AVC on / off condition judgment submodule and the whole plant AVC on / off condition judgment submodule. After the first stage of the main process starts, firstly, according to the external input instruction, the whole plant AVC setting mode is selected as the curve mode or the fixed value mode, and then the whole plant reactive power / voltage setting mode submodule is executed to select the whole plant setting control mode, and then the single machine AVC on / off condition judgment submodule and the whole plant AVC on / off condition judgment submodule are executed. Figure 4 , Figure 5 , Figure 7 and Figure 8 The single-machine input condition, single-machine exit condition, whole-plant input condition and front-end exit condition 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, it returns to continue executing the above three sub-modules.

[0025] The submodules included in the second stage include 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, first determine whether it is in the reactive power given control mode. If so, execute the input fault tolerance check submodule and the reactive power given control mode submodule in sequence. Otherwise, continue to determine whether it is in the voltage given control mode. If so, execute the voltage given control mode submodule, otherwise return to the beginning of the second stage. The AVC reactive distribution value of the whole 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.

[0026] The submodules included in the third stage include the equal power factor allocation submodule, the reactive capacity proportional allocation submodule and the similar adjustment margin allocation submodule. After the third stage of the main process starts, first determine whether to allocate according to the equal power factor mode. If so, execute the equal power factor allocation submodule. Otherwise, continue to determine whether to allocate according to the reactive capacity proportional mode. If so, execute the reactive capacity proportional allocation submodule. Otherwise, continue to determine whether to allocate according to the similar adjustment margin mode. If so, execute the similar adjustment margin allocation submodule. Otherwise, return to the beginning of the third stage. After calculating the AVC allocation value of each unit put into AVC through the selected reactive power allocation mode, determine whether AVC is in closed-loop regulation. If so, send the AVC allocation value of each unit and end the main process. Otherwise, end the main process directly.

[0027] See also Figure 2, the whole plant reactive power / voltage setting mode submodule flow chart, after the process starts, first determine whether it is the curve mode, if so, switch the AVC control right to the power plant, and switch to the voltage setting control mode, assign the bus voltage setting value to the current value of the curve voltage, and transfer to the end of the process, otherwise continue to determine whether it is the fixed value mode, if so, return to the beginning of the process, if so, determine whether the AVC control right belongs to the power plant, if so, determine whether it is the reactive power setting control mode, if so, assign the reactive power setting value of the whole plant to the setting value on the AVC screen by the power plant operator, and transfer to the end of the process, otherwise continue to determine whether it is the voltage setting control mode, if so, assign the bus voltage setting value to the setting value on the AVC screen by the power plant operator, and transfer to the end of the process, 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, continue to determine whether the AVC control right belongs to the dispatcher If it is, determine whether it is a 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 a 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 a 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 a 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 a 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 a reactive power given control mode.

[0028] See also Figure 3 , Figure 4 and Figure 5 As shown, the flow chart of the stand-alone AVC investment and withdrawal condition judgment submodule, after the process starts, first determine whether the stand-alone AVC has been invested, if so, continue to determine whether the stand-alone AVC automatic exit condition is met, if so, automatically exit the stand-alone AVC, and enter the end of the process, otherwise continue to determine whether there is a stand-alone AVC exit instruction, if so, exit the stand-alone AVC and enter the end of the process, otherwise directly enter 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, continue to determine whether the stand-alone AVC investment condition is met, if not, directly enter the end of the process, if so, continue to determine whether there is a stand-alone AVC investment instruction, if so, invest the stand-alone AVC and enter the end of the process, otherwise directly enter the end of the process.

[0029] 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 system is normal, the unit is in grid-connected state, the unit reactive power measurement 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 system is abnormal, the unit is not in grid state, the unit reactive power measurement is inaccurate, the system bus voltage exceeds the upper and lower limits of the fault voltage, and the whole field AVC switches from activation to exit.

[0030] See also Figure 6 , Figure 7 and Figure 8 , after the process starts, first determine whether the whole plant AVC has been put into operation. If so, continue to determine whether the whole plant AVC automatic exit conditions are met. If so, automatically exit the whole plant AVC and transfer to the end of the process. Otherwise, continue to determine whether there is a whole plant AVC exit instruction. If so, exit the whole plant AVC and transfer to the end of the process. Otherwise, directly transfer to the end of the process. If the result of the first judgment link of the process is that the whole plant AVC has not been put into operation, continue to determine whether the whole plant AVC investment conditions are met. If so, directly transfer to the end of the process. If so, continue to determine whether there is a whole plant AVC investment instruction. If so, invest the whole plant AVC and transfer to the end of the process. Otherwise, directly transfer to the end of the process.

[0031] Among them, the conditions for the start of AVC in the whole plant include that at least one unit is put into single-stage AVC mode, the system bus voltage does not exceed the upper and lower limits of the fault voltage, there is no oscillation in the system bus voltage, 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 automatic exit of AVC in the whole plant include that no unit is put into 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.

[0032] See also Fig. 9 As 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 whole 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 whole plant, and the process ends. Otherwise, the whole plant AVC is exited and the process ends.

[0033] According to the functional requirements and development requirements of the AVC logic configuration of a hydropower plant, this embodiment proposes a hydropower plant automatic voltage control (AVC) logic configuration design scheme. Through the AVC logic configuration design scheme of the present invention, the main process framework is designed, and then the functions of each submodule are designed, and then the external interface and internal algorithm of each submodule are designed. The specific implementation steps are as follows: The main process framework of a hydropower plant automatic voltage control logic configuration method can be divided into three stages.

[0034] The function of the first stage is to determine whether the whole plant AVC is in operation and 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 include 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 determined whether the plant-wide AVC is put into operation. If it is, the second stage of the main process is entered. If not, it returns to continue executing the above three sub-module processes.

[0035] 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 setting control mode submodule in Table 2. The single-machine AVC on-off condition judgment submodule switches the on-off state of the single-machine AVC according to the on-off conditions of the single-machine AVC (single-machine AVC on-off conditions: 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 system is normal, the unit is in the 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; single-machine AVC exit conditions: 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 system is abnormal, the unit is not in the grid-connected 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 whole plant 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-machine 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-machine 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 submodule switches the plant-wide AVC on-off status according to the plant-wide AVC on-off conditions.

[0036] Table 1

[0037] 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 that 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: Table 2

[0038] The function of the third stage is to calculate the AVC allocation value of each unit put into AVC, and when AVC is in closed-loop regulation mode, the AVC allocation value is sent to each unit. The submodules included in the third stage are equal power factor allocation submodule, reactive capacity proportional allocation submodule and similar adjustment margin allocation submodule. After the process enters the third stage, it is first determined whether it is allocated according to the equal power factor mode. If it is determined to be allocated according to the equal power factor mode, the equal power factor allocation submodule is executed, otherwise it continues to determine whether it is allocated according to the reactive capacity proportional mode. If so, the reactive capacity proportional allocation submodule is executed, otherwise it is necessary to determine whether it is allocated 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 of each unit put into AVC through the selected reactive distribution mode, it is determined whether AVC is in closed-loop regulation. If so, the AVC allocation value of each unit is sent down and the main process ends, otherwise the main process ends directly. The functions, external interfaces and internal algorithm designs of the three submodules of the third stage are shown in Table 3: Table 3

[0039] In addition, it should be understood that although this specification is described in accordance with the implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art. The above content is only to illustrate the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution according to the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for configuring the automatic voltage control logic of 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 to determine whether the single-machine AVC is in the single-machine AVC input state or the single-machine AVC exit state; Step 3: Determine whether the selection of the external input command and the AVC startup and shutdown status of the single machine meet the AVC startup and shutdown conditions of the whole plant, and after determination, determine whether the AVC startup status of the whole plant is the AVC startup of the whole plant; Step 4: If the AVC switch-on / off state of the whole plant is determined to be the AVC switch-on state of the whole plant in step 3, determine whether it is the reactive power setting control mode according to the AVC setting control mode of the whole plant in step 1. If the AVC setting control mode of the whole plant is the reactive power setting control mode, calculate the reactive power setting distribution value of the whole plant; otherwise, the AVC setting control mode of the whole plant is the voltage setting control mode, calculate the voltage setting distribution value of the whole plant; Step 5: If the AVC status of the whole plant is determined to be off in step 3, re-enter the command and repeat steps 1 to 3; Step 6: Calculate the AVC distribution value according to the plant-wide AVC reactive power distribution value in step 4; Step 7: Determine whether AVC is a closed-loop regulation according to the external input command. If it is a closed-loop regulation, the AVC of each unit is issued according to the AVC allocation value and the process is terminated. If it is not a closed-loop regulation, the process is terminated directly.

2. A hydropower plant automatic voltage control logic configuration method according to claim 1, characterized in that: In the step 1, the whole plant AVC given control mode is determined. It is necessary to first determine the whole plant given mode according to the external input instructions. If the curve method is adopted, the whole plant AVC control right belongs to the power plant, and the whole plant AVC given control mode is the whole plant voltage given control mode. If the fixed value method 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 method nor the fixed value method is adopted, the external input instruction is re-performed to select whether to adopt the curve method.

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 AVC given control mode of the whole plant is judged whether it is the reactive power given control mode or the voltage given control mode according to the external input instructions. If it is neither, the AVC given control mode of the whole plant is re-judged 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 judged 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 set value 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 set value 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 the reactive setting control mode, the whole plant AVC reactive power distribution of the reactive setting mode is calculated by the reactive setting control mode. ,in, For: AVC reactive power distribution of the whole plant, =: 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 the 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 able to set the value and an error will be reported; the upper limit calculation method of the whole plant reactive setting value is: , is the maximum reactive power sum of the AVC units under the current working conditions, n is the number of AVC units put into operation; the calculation method of 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 by the voltage given control mode. 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, is: the AVC reactive power distribution value of the whole plant when the system bus voltage is within the normal voltage value range, The AVC reactive power distribution value of the whole plant when the system bus voltage exceeds the normal voltage value 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 voltage 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 allocation mode of AVC 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 to allocate according to equal power factors. If so, AVC will be allocated according to equal power factors; otherwise, determine whether to allocate according to proportional reactive capacity. If so, AVC will be allocated according to proportional reactive capacity; otherwise, determine whether to allocate according to similar adjustment margin. If so, AVC will be allocated according to similar adjustment margin; if none of the three allocation methods is selected, re-enter the command to determine the three allocation methods of AVC.

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: ;in, =Equal power allocation value for each AVC, The reactive capacity of each AVC is proportional to the distribution value. 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 use, is the current reactive power value, and are given externally.

Images