Hydroelectric generating unit excitation parameter adjustment method and system based on working condition recognition

Abstract

The application provides a water turbine generator excitation parameter adjustment method and system based on working condition recognition, belongs to the technical field of water turbine generator excitation control, and can at least partially solve the problems that the existing control mode is difficult to adapt to the frequent change of the working condition of the water turbine generator, lacks an effective recognition mechanism for the working condition, and is difficult to realize self-adaptive adjustment of the excitation parameter under multiple working conditions. The application comprises the following steps: running state data acquisition; working condition recognition; working condition determination confirmation; working condition-excitation parameter mapping and matching; and online self-adaptive adjustment of the excitation parameter. The application can accurately recognize multiple working conditions of the water turbine generator in real time by collecting the running state data of the water turbine generator and recognizing the working condition, thereby establishing a systematic mapping relationship between the working condition and the excitation parameter, realizing self-adaptive adjustment of the excitation system, and improving the dynamic performance and adaptability of the water turbine generator in a complex power system environment.

Description

Technical Field

[0001] This invention belongs to the field of hydropower unit excitation control technology, specifically relating to a method and system for adjusting hydropower unit excitation parameters based on operating condition identification. Background Technology

[0002] Hydropower units are crucial synchronous power sources in power systems. Their excitation systems, controlled by automatic voltage regulators (ATRs), play a vital role in maintaining unit voltage stability, participating in grid reactive power regulation, and enhancing system stability. With changes in power system structure, hydropower units now routinely operate under various conditions, including start-up and shutdown, load changes, low-load operation, and grid disturbances. This places higher demands on the dynamic performance and adaptability of the excitation system. Currently, the parameters of the ATRs in hydropower unit excitation systems are typically determined offline before unit commissioning and remain fixed during operation. This method, primarily based on manual experience or typical operating conditions, can meet basic voltage regulation requirements under stable unit operation and is therefore widely adopted in engineering.

[0003] However, existing control methods using fixed excitation parameters are ill-suited to the frequent changes in operating conditions of hydropower units. When the unit is in start-up, shutdown, or experiencing grid disturbances, the excitation system needs a fast voltage response. Conversely, under low load or stable operating conditions, excessively high control gain can easily cause voltage fluctuations or even oscillations. Existing technologies struggle to achieve a balance between response speed and system stability under different operating conditions. Furthermore, while existing technologies offer solutions for optimizing the excitation system through parameter tuning or simple logic switching, most lack an effective mechanism for identifying operating conditions, fail to establish a systematic correlation between operating conditions and excitation parameter adjustments, and do not adequately consider the continuity of operating conditions and the smoothness of parameter switching. This makes it difficult to achieve adaptive adjustment of excitation parameters under multiple operating conditions. Therefore, we propose a hydropower unit excitation parameter adjustment method and system based on operating condition identification. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art, and provides a method and system for adjusting the excitation parameters of hydropower units based on operating condition identification.

[0005] This invention provides a method for adjusting the excitation parameters of a hydropower unit based on operating condition identification, comprising the following steps:

[0006] S1: Collect the operating status data of the hydropower unit;

[0007] S2: Based on the operating status data, identify the current operating condition of the hydropower unit;

[0008] S3: Determine and confirm the identified operating conditions. When the operating conditions meet the preset stability determination conditions, confirm the current operating conditions.

[0009] S4: Based on the confirmed operating conditions, select the excitation parameter configuration scheme corresponding to the current operating conditions from the pre-built operating condition-excitation parameter mapping relationship;

[0010] S5: Based on the excitation parameter configuration scheme, adjust the parameters of the automatic voltage regulator of the hydropower unit excitation system online.

[0011] Furthermore, the operating conditions include one or more of the following: start-stop operating conditions, stable operating conditions, variable load operating conditions, low load operating conditions, and grid disturbance operating conditions.

[0012] Specifically, the operating status data includes at least the terminal voltage, active power, reactive power, speed status, and excitation current.

[0013] Specifically, in step S2, the identification of the operating condition includes the following steps: based on at least two operating characteristic quantities among the generator terminal voltage change rate, active power change rate, reactive power change rate and speed state calculated from the operating status data, a set of operating condition criteria is constructed, and the operating condition of the hydropower unit is determined by comprehensively analyzing the change characteristics of the operating characteristic quantities within a preset time window.

[0014] Preferably, in step S3, the determination and confirmation of the identified operating conditions includes the following steps: performing consistency verification on the results of the operating condition identification within multiple consecutive sampling periods, and confirming the current operating condition when the results of the operating condition identification remain consistent within a preset duration; and maintaining the initial excitation parameter configuration scheme of the hydropower unit unchanged when the results of the operating condition identification do not remain consistent within the multiple consecutive sampling periods.

[0015] Specifically, in step S4, the excitation parameter configuration scheme includes a set of parameters corresponding to the operating condition. The set of parameters includes one or more of the following parameters: the proportional parameter, integral parameter, dynamic response time constant parameter of the automatic voltage regulator, and the limit parameter of the excitation limiter of the excitation system.

[0016] Furthermore, in step S5, when adjusting the excitation parameters online, different transition control strategies are applied to the parameter change process according to the type of the excitation parameters, including limiting the amplitude of parameter change or limiting the slope of parameter change rate, in order to suppress sudden changes in the excitation output of the excitation system.

[0017] Furthermore, in step S3, when the grid disturbance condition is identified, an excitation parameter configuration scheme aimed at improving voltage support capability is adopted. This is achieved by increasing the control gain of the automatic voltage regulator or shortening its response time constant to regulate the generator terminal voltage. When the low load operation condition is identified, an excitation parameter configuration scheme aimed at suppressing voltage fluctuations is adopted. This is achieved by reducing the control gain of the automatic voltage regulator or strengthening parameter change constraints to reduce the amplification effect of the excitation system on voltage disturbances.

[0018] Another aspect of the present invention provides a hydropower unit excitation parameter adjustment system based on operating condition identification, the system being adapted to implement the above-described hydropower unit excitation parameter adjustment method based on operating condition identification, comprising: integrated into the hydropower unit excitation control device.

[0019] The data acquisition module is used to collect the operating status data of the hydropower unit;

[0020] The operating condition identification module is used to identify the operating condition of the hydropower unit based on the operating status data;

[0021] The strategy decision module is used to select the corresponding excitation parameter configuration scheme based on the identified and confirmed operating conditions; and

[0022] The excitation parameter adjustment module is used to adjust the parameters of the automatic voltage regulator online according to the excitation parameter configuration scheme.

[0023] Specifically, the excitation control device further includes:

[0024] One or more processors;

[0025] The memory stores a computer program that, when executed by one or more processors, enables the processors to implement the above-described method for adjusting the excitation parameters of a hydropower unit based on operating condition identification.

[0026] The beneficial effects of this invention are as follows:

[0027] By collecting operating status data of hydropower units and identifying operating conditions, various operating conditions of the units can be identified in real time and accurately. This establishes a systematic mapping relationship between operating conditions and excitation parameters, overcoming the insufficient adaptability caused by fixed excitation parameters in existing technologies. It enables adaptive adjustment of the excitation system, improving the dynamic performance and adaptability of hydropower units in complex power system environments. After operating condition identification, the identification results are confirmed through consistency verification and preset stability judgment conditions. Transitional control strategies are applied during parameter adjustment, effectively suppressing sudden changes in excitation output during parameter switching, avoiding voltage fluctuations or oscillations, ensuring a smooth transition and overall stability of the excitation system, and significantly improving the reliability and safety of hydropower units under frequent operating condition changes. Attached Figure Description

[0028] Figure 1 This is a flowchart illustrating the steps of a hydropower unit excitation parameter adjustment method based on operating condition identification, according to a specific embodiment of the present invention.

[0029] Figure 2 The control logic diagram of a hydropower unit excitation parameter adjustment method based on operating condition identification is shown in a specific embodiment of the present invention.

[0030] Figure 3 The active power change rate curve of the hydropower unit excitation parameter adjustment system based on operating condition identification in a specific embodiment of the present invention is shown.

[0031] Figure 4 A speed variation curve of a hydropower unit excitation parameter adjustment system based on operating condition identification, according to a specific embodiment of the present invention, in the grid-connected operation state.

[0032] Figure 5 The active power change rate curve of the hydropower unit excitation parameter adjustment system based on operating condition identification in a specific embodiment of the present invention is shown.

[0033] Figure 6 This is a diagram showing the generator terminal voltage fluctuation curve under low load operation of a hydropower unit excitation parameter adjustment system based on operating condition identification, according to a specific embodiment of the present invention. Detailed Implementation

[0034] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] The present invention provides a method for adjusting the excitation parameters of a hydropower unit based on operating condition identification, comprising the following steps:

[0036] S1: Collect operating status data of hydropower units;

[0037] S2: Identify the current operating conditions of the hydropower unit based on the operating status data;

[0038] S3: Determine and confirm the identified operating conditions. When the operating conditions meet the preset stability determination conditions, confirm the current operating conditions.

[0039] S4: Based on the confirmed operating conditions, select the excitation parameter configuration scheme corresponding to the current operating conditions from the pre-built operating condition-excitation parameter mapping relationship;

[0040] S5: Based on the excitation parameter configuration scheme, the parameters of the automatic voltage regulator of the hydropower unit excitation system are adjusted online to realize the adjustment of the hydropower unit excitation parameters.

[0041] Specifically, in step S1, the above-mentioned operating status data is processed according to a uniform sampling period. Data is collected and compiled into a sequence of unit operating status data for subsequent condition identification and judgment.

[0042] Furthermore, in step S2, the operating condition of the unit is determined by constructing the following operating condition criteria:

[0043] Start-up and shutdown condition determination: When the unit speed is detected to be in the process of increasing or decreasing speed, and the terminal voltage and active power are gradually built up or gradually disappearing from zero, the unit is determined to be in start-up and shutdown condition.

[0044] Stable operating condition determination: When the unit speed is stable, the rate of change of active power and the rate of change of reactive power are both less than the preset threshold, and the terminal voltage fluctuates within the allowable deviation range, the unit is determined to be in a stable operating condition.

[0045] Variable load operation condition determination: When the unit speed remains stable, but the rate of change of active power or reactive power exceeds the preset change threshold in a short period of time, the unit is determined to be in a variable load operation condition.

[0046] Low-load operation condition determination: When the unit is in grid-connected state and the active power is in the low-load range of the rated power, and the active power change rate is small but the terminal voltage fluctuation is relatively obvious, the unit is determined to be in low-load operation condition.

[0047] Grid disturbance condition determination: When the generator terminal voltage deviates significantly in a short period of time, or the reactive power change rate changes drastically in a short period of time, while the active power of the generator does not increase significantly, the generator is determined to be in grid disturbance condition.

[0048] In actual operation, when multiple operating condition criteria are met simultaneously, the operating condition is determined according to a preset priority rule, with start-up / shutdown conditions and grid disturbance conditions having higher priority than stable operation conditions and low-load operation conditions. Furthermore, the operating condition identification result needs to be confirmed by consistency verification over multiple consecutive sampling periods. Only when the same operating condition is consistently met within a preset time period can it be considered the final operating condition identification result.

[0049] Furthermore, in step S3, due to short-term fluctuations or measurement noise during the operation of the hydropower unit, in order to avoid frequent switching of operating conditions, the identified operating conditions are determined and confirmed in step S3; the consistency of the operating condition identification results is checked within multiple consecutive sampling periods, and when the same operating condition is within a preset duration... When the internal conditions remain consistent, the current operating condition is confirmed; when the operating condition identification result does not meet the consistency condition, the original excitation parameter configuration scheme is maintained unchanged, thereby avoiding frequent switching of excitation parameters due to misjudgment.

[0050] Based on the above basic implementation method, the operating conditions include one or more of the following: start-stop operating conditions, stable operating conditions, variable load operating conditions, low load operating conditions, and power grid disturbance operating conditions.

[0051] In one specific implementation, the operating status data includes at least the terminal voltage. Active power reactive power Speed ​​status and excitation current .

[0052] In this embodiment, at least two operational feature quantities can be extracted from the operational status data to construct a set of operating condition criteria:

[0053] Feature 1: Terminal voltage change rate: ;

[0054] Feature 2: Rate of change of active power: ;

[0055] Feature 3: Reactive power change rate: ;

[0056] Feature 4: Speed ​​status or grid connection status indicator: within a preset time window Within this process, the changing characteristics of the aforementioned operating features are comprehensively analyzed, and the current operating status of the hydropower unit is classified and identified based on a pre-set set of operating condition criteria to obtain candidate operating condition types.

[0057] In another specific embodiment, in step S2, the identification of operating conditions includes at least: constructing a set of operating condition criteria based on at least two operating characteristic quantities among the generator terminal voltage change rate, active power change rate, reactive power change rate and speed status, and determining the current operating condition of the hydropower unit by comprehensively analyzing the change characteristics of the operating characteristic quantities within a preset time window.

[0058] Specifically, in step S3, the determination and confirmation of the identified operating conditions includes: performing consistency verification on the results of operating condition identification within multiple consecutive sampling periods, and confirming the current operating condition when the results of operating condition identification remain consistent within a preset duration; and maintaining the initial excitation parameter configuration scheme of the hydropower unit unchanged when the results of operating condition identification do not meet the consistency conditions.

[0059] In another specific embodiment, in step S4, the excitation parameter configuration scheme includes a set of parameters corresponding to the operating conditions. The set of parameters includes one or more of the following parameters: the proportional parameter, integral parameter, dynamic response time constant parameter of the automatic voltage regulator, and the limit parameter of the excitation limiter of the excitation system. In step S5, when adjusting the excitation parameters online, different transition control strategies are applied to the parameter change process according to the type of excitation parameter, including limiting the amplitude of parameter change or limiting the slope of parameter change rate, so as to suppress the sudden change of excitation output in the excitation system.

[0060] Furthermore, a mapping relationship between operating conditions and excitation parameter configuration schemes is pre-established; the excitation parameter configuration schemes exist in the form of parameter sets, with each operating condition corresponding to at least one parameter set, and each parameter set including at least one or a combination of the following:

[0061] Automatic voltage regulator proportional parameters ;

[0062] Automatic voltage regulator integral parameters ;

[0063] Dynamic response time constant parameter ;

[0064] Limit parameters of the excitation limiter;

[0065] The parameter sets corresponding to different operating conditions are different in terms of parameter values ​​or parameter combination structure, so that the excitation control characteristics are matched with the operating conditions.

[0066] The principles for configuring excitation parameters for different operating conditions are as follows:

[0067] Start-up and shutdown conditions: The corresponding parameter configuration scheme aims to smoothly establish or release excitation, and suppresses sudden changes in excitation output by reducing control gain or strengthening parameter change constraints;

[0068] Stable operating conditions: The corresponding parameter configuration scheme is adopted with the goal of voltage stability regulation, so that the automatic voltage regulator can maintain good stability while ensuring steady-state accuracy;

[0069] Variable load operation: The corresponding parameter configuration scheme is adopted to balance response speed and stability, so that the excitation system can adapt to the process of rapid power change;

[0070] Low-load operation: The corresponding parameter configuration scheme is adopted to suppress voltage fluctuations. By reducing the control gain or strengthening the constraint of parameter changes, the amplification effect of voltage regulation is reduced.

[0071] Grid disturbance conditions: A parameter configuration scheme aimed at improving voltage support capability is adopted, achieving rapid response of the generator terminal voltage by increasing control gain or shortening the response time constant. Once a certain operating condition is confirmed, the system automatically selects the parameter set corresponding to the current operating condition based on the mapping relationship between the operating condition and the excitation parameter configuration scheme, and transmits it as the target parameter configuration scheme to the online adjustment step of the excitation parameters for subsequent parameter transition control and loading execution. In step S5, the parameters of the automatic voltage regulator of the excitation system are adjusted online according to the selected excitation parameter configuration scheme. Without changing the basic structure of the excitation control, by loading a parameter set matching the current operating condition, the parameters of the automatic voltage regulator are dynamically updated, enabling the excitation system to exhibit different regulation characteristics under different operating conditions.

[0072] Furthermore, in step S3, when the grid disturbance condition is identified, an excitation parameter configuration scheme aimed at improving voltage support capability is adopted. This is achieved by increasing the control gain of the automatic voltage regulator or shortening its response time constant to regulate the generator terminal voltage. When the low load operation condition is identified, an excitation parameter configuration scheme aimed at suppressing voltage fluctuations is adopted. This is achieved by reducing the control gain of the automatic voltage regulator or strengthening parameter change constraints to reduce the amplification effect of the excitation system on voltage disturbances.

[0073] During the online adjustment of excitation parameters, in order to avoid excitation output fluctuations caused by parameter abrupt changes, different transition control strategies are applied to the parameter change process according to the parameter type, including: limiting the amplitude of parameter change and limiting the slope of parameter change rate.

[0074] The parameter update process can be represented as: ,in, For the target parameter value, This is the transition coefficient.

[0075] In one specific implementation, such as Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, the present invention provides a hydropower unit excitation parameter adjustment system based on operating condition identification. The system is suitable for implementing the above-described hydropower unit excitation parameter adjustment method based on operating condition identification, and includes the following components integrated into the hydropower unit excitation control device:

[0076] The system includes a data acquisition module for collecting operating status data of the hydropower unit; an operating condition identification module for identifying the operating conditions of the hydropower unit based on the operating status data; a strategy decision module for selecting the corresponding excitation parameter configuration scheme based on the identified and confirmed operating conditions; and an excitation parameter adjustment module for adjusting the parameters of the automatic voltage regulator online according to the excitation parameter configuration scheme.

[0077] In this embodiment, a mixed-flow hydropower unit is used as an example to illustrate the specific application process of the adaptive adjustment method for the excitation parameters of the hydropower unit: the rated capacity of the hydropower unit is 300MW, the rated terminal voltage is 15.75kV, the rated frequency is 50Hz, the excitation system adopts static excitation mode, and the automatic voltage regulator is a proportional-integral (PI) control structure. The system operation data sampling period is set to 100ms.

[0078] During the time interval t0 to t1, the unit is in grid-connected operation, and the speed is stable near the rated speed (speed deviation less than ±0.05%). Figure 4 (As shown), but due to changes in dispatch instructions, the unit load gradually decreased from 260MW to 140MW, as... Figure 3 As shown. During this process, the system collected the following operational data:

[0079] Rate of change of active power Reactive power change rate Terminal voltage fluctuation amplitude ;

[0080] The operating condition identification module determines that the unit is in a variable load operating condition based on the criteria of "stable speed + significant change rate of active power". If this determination remains consistent for 2 consecutive seconds, the strategy decision module confirms the current operating condition as a variable load operating condition. The system then selects the excitation parameter configuration scheme corresponding to the variable load operating condition from the operating condition-excitation parameter mapping relationship, and the automatic voltage regulator proportional parameters... Automatic voltage regulator integral parameters Dynamic response time constant .

[0081] Specifically, the above parameter configuration enables the excitation system to balance response speed and operational stability during load changes; when the unit load further decreases and stabilizes at around 90MW, the active power change rate gradually decreases to ,like Figure 5 As shown, however, due to the unit operating in the low-load range, the system detected an increase in the voltage fluctuation amplitude at the generator terminals, reaching [a certain value]. ,like Figure 6 As shown;

[0082] The operating condition identification module identifies the unit as entering a low-load operating condition based on the criteria of "grid-connected operation + active power in a low-load range + small power change rate but relatively significant voltage fluctuation." After the identification result remains consistent for 3 consecutive seconds, the strategy decision module confirms the switch to low-load operating condition and calls the excitation parameter configuration scheme corresponding to the low-load operating condition. Under low-load operating condition, the system selects an excitation parameter configuration scheme aimed at suppressing voltage fluctuations: automatic voltage regulator proportional parameters. Automatic voltage regulator integral parameters Dynamic response time constant During parameter switching, the excitation parameter adjustment module uses a slope limiting method for smooth transition, and the rate of change of the proportional parameter is limited as follows:

[0083] ;

[0084] Through the above parameter adjustments, the voltage fluctuation range at the turbine terminals was reduced from approximately ±0.8% to within ±0.3%, and the excitation current change was smooth without significant abrupt changes, significantly improving the unit's operational stability. This embodiment demonstrates that during the transition from variable load operation to low load operation, this invention can: accurately identify changes in the unit's operating conditions; automatically select a matching excitation parameter configuration scheme based on the operating conditions; avoid abrupt changes in excitation output through a parameter smoothing switching mechanism; and effectively suppress voltage fluctuations at the turbine terminals under low load operating conditions. This verifies the effectiveness and engineering feasibility of this invention in adaptively adjusting the excitation parameters of hydropower units under multiple operating conditions.

[0085] To aid in a better understanding of the present invention, a more comprehensive and specific embodiment is described, in which the present invention provides a method for adjusting the excitation parameters of a hydropower unit based on operating condition identification, comprising the following steps:

[0086] S1: Collect operating status data of hydropower units;

[0087] S2: Identify the current operating conditions of the hydropower unit based on the operating status data;

[0088] S3: Determine and confirm the identified operating conditions. When the operating conditions meet the preset stability determination conditions, confirm the current operating conditions.

[0089] S4: Based on the confirmed operating conditions, select the excitation parameter configuration scheme corresponding to the current operating conditions from the pre-built operating condition-excitation parameter mapping relationship;

[0090] S5: Based on the excitation parameter configuration scheme, the parameters of the automatic voltage regulator of the hydropower unit excitation system are adjusted online to realize the adjustment of the hydropower unit excitation parameters.

[0091] In this embodiment, the operating conditions include one or more of the following: start-up and shutdown, stable operation, variable load operation, low load operation, and grid disturbance operation; the operating status data includes at least the generator terminal voltage, active power, reactive power, speed status, and excitation current; in step S2, the identification of the operating conditions includes at least: constructing a set of operating condition criteria based on at least two operating characteristic quantities among the generator terminal voltage change rate, active power change rate, reactive power change rate, and speed status, and determining the current operating condition of the hydropower unit by comprehensively analyzing the change characteristics of the operating characteristic quantities within a preset time window; in step S3, the determination and confirmation of the identified operating conditions includes: performing consistency verification on the results of the operating condition identification within multiple consecutive sampling periods, and confirming the current operating condition when the results of the operating condition identification remain consistent within a preset duration; when the results of the operating condition identification do not meet the consistency condition, maintaining the initial excitation parameter configuration scheme of the hydropower unit unchanged; in step S4, the excitation... The parameter configuration scheme includes a set of parameters corresponding to the operating conditions. The parameter set includes one or more of the following parameters: proportional parameters, integral parameters, dynamic response time constant parameters of the automatic voltage regulator, and limit parameters of the excitation limiter of the excitation system. In step S5, when adjusting the excitation parameters online, different transition control strategies are applied to the parameter change process according to the type of excitation parameter, including limiting the amplitude of parameter change or limiting the slope of parameter change rate, in order to suppress sudden changes in the excitation output of the excitation system. In step S3, when the grid disturbance condition is identified, an excitation parameter configuration scheme aimed at improving voltage support capability is adopted, which adjusts the generator terminal voltage by increasing the control gain of the automatic voltage regulator or shortening its response time constant. When the low load operating condition is identified, an excitation parameter configuration scheme aimed at suppressing voltage fluctuations is adopted, which reduces the amplification effect of the excitation system on voltage disturbances by reducing the control gain of the automatic voltage regulator or strengthening parameter change constraints.

[0092] Specifically, another aspect of the present invention provides a hydropower unit excitation parameter adjustment system based on operating condition identification. The system is suitable for implementing the above-described hydropower unit excitation parameter adjustment method based on operating condition identification, and includes components integrated into the hydropower unit excitation control device:

[0093] The system includes a data acquisition module for acquiring the operating status data of the hydropower unit; an operating condition identification module for identifying the operating conditions of the hydropower unit based on the operating status data; a strategy decision module for selecting a corresponding excitation parameter configuration scheme based on the identified and confirmed operating conditions; and an excitation parameter adjustment module for adjusting the parameters of the automatic voltage regulator online according to the excitation parameter configuration scheme. The excitation control device also includes one or more processors and a memory containing a computer program. When the computer program is executed by one or more processors, it enables the one or more processors to implement the above-described hydropower unit excitation parameter adjustment method based on operating condition identification.

[0094] In summary, the embodiments disclosed herein have at least the following technical effects:

[0095] By collecting operating status data of hydropower units and identifying operating conditions, multiple operating conditions of the units can be identified in real time and accurately. This establishes a systematic mapping relationship between operating conditions and excitation parameters, overcoming the problem of insufficient adaptability caused by fixed excitation parameters in existing technologies. It enables adaptive adjustment of the excitation system and improves the dynamic performance and adaptability of hydropower units in complex power system environments.

[0096] After the operating condition is identified, the identification result is confirmed by consistency verification and preset stability judgment conditions. During the parameter adjustment process, a transition control strategy is applied to effectively suppress the excitation output sudden change during parameter switching, avoid voltage fluctuation or oscillation, ensure the smooth transition and overall stability of the excitation system, and significantly improve the reliability and safety of the hydropower unit under frequent operating condition changes.

[0097] Selecting appropriate excitation parameter configuration schemes based on different operating conditions, such as increasing control gain to enhance voltage support capability under grid disturbance conditions and reducing control gain to suppress voltage fluctuation amplification effect under low load operating conditions, can balance response speed and system stability, optimize the control effect of the excitation system, enhance the contribution of hydropower units to grid reactive power regulation and system stability, and is suitable for the diverse operating needs under the modern power system structure.

[0098] The system is integrated into the excitation control device, including an operation data acquisition module, an operating condition identification module, a strategy decision-making module, and an excitation parameter adjustment module. The method is executed through a processor and memory. It has a simple structure, is easy to implement, and has high engineering practical value. It can reduce the dependence on manual intervention and improve the automation level and operating efficiency of hydropower units.

[0099] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for adjusting the excitation parameters of a hydropower unit based on operating condition identification, characterized in that, Includes the following steps: S1: Collect the operating status data of the hydropower unit, which includes at least the terminal voltage, active power, reactive power, speed status and excitation current; S2: Based on the operating status data, identify the current operating condition of the hydropower unit. The operating condition includes one or more of the following: start-up and shutdown, stable operation, variable load operation, low load operation, and grid disturbance operation. The identification of the operating condition includes the following steps: based on at least two operating characteristic quantities among the generator terminal voltage change rate, active power change rate, reactive power change rate, and speed state calculated from the operating status data, construct a set of operating condition criteria, and determine the current operating condition of the hydropower unit by comprehensively analyzing the change characteristics of the operating characteristic quantities within a preset time window. S3: Determine and confirm the identified operating condition, perform consistency verification on the results of the operating condition identification within multiple consecutive sampling periods, and confirm the current operating condition when the results of the operating condition identification remain consistent within a preset duration. When the result of the operating condition identification does not meet the consistency condition, the initial excitation parameter configuration scheme of the hydropower unit remains unchanged; S4: Based on the confirmed operating condition, select an excitation parameter configuration scheme corresponding to the current operating condition from the pre-built operating condition-excitation parameter mapping relationship. The excitation parameter configuration scheme includes a parameter set corresponding to the operating condition. The parameter set includes one or more of the following parameters: proportional parameters, integral parameters, dynamic response time constant parameters of the automatic voltage regulator, and limit parameters of the excitation limiter of the excitation system. S5: Based on the excitation parameter configuration scheme, the parameters of the automatic voltage regulator of the hydropower unit excitation system are adjusted online. When adjusting the excitation parameters online, different transition control strategies are applied to the parameter change process according to the type of excitation parameter, including limiting the amplitude of parameter change or limiting the slope of parameter change rate, so as to suppress the sudden change of excitation output in the excitation system. Specifically, when the operating condition is identified as a grid disturbance, an excitation parameter configuration scheme aimed at improving voltage support capability is adopted. This is achieved by increasing the control gain of the automatic voltage regulator or shortening its response time constant to regulate the generator terminal voltage. When the operating condition is identified as a low-load operation, an excitation parameter configuration scheme aimed at suppressing voltage fluctuations is adopted. This is achieved by reducing the control gain of the automatic voltage regulator or strengthening parameter change constraints to reduce the amplification effect of the excitation system on voltage disturbances.

2. A hydropower unit excitation parameter adjustment system based on operating condition identification, characterized in that, The system is suitable for implementing the hydropower unit excitation parameter adjustment method based on operating condition identification according to claim 1, including the following integrated into the hydropower unit excitation control device: The data acquisition module is used to collect the operating status data of the hydropower unit; The operating condition identification module is used to identify the operating condition of the hydropower unit based on the operating status data; The strategy decision module is used to select the corresponding excitation parameter configuration scheme based on the identified and confirmed operating conditions. as well as The excitation parameter adjustment module is used to adjust the parameters of the automatic voltage regulator online according to the excitation parameter configuration scheme.

3. The hydropower unit excitation parameter adjustment system based on operating condition identification according to claim 2, characterized in that, The excitation control device also includes: One or more processors; The memory stores a computer program that, when executed by the one or more processors, enables the one or more processors to implement the hydropower unit excitation parameter adjustment method based on operating condition identification as described in claim 1.

Images