Inertial support-containing fast response coordination control system for hybrid synchronous phase modifier

Abstract

The invention relates to the technical field of power system stability control, and discloses a hybrid synchronous phase modifier quick response coordination control system with inertia support. According to the invention, wide-area data such as voltage phase, frequency deviation and the like are collected and verified through the data sensing module; the modal evaluation module calculates a global motion modal cooperation coefficient G to quantify the dynamic cooperation degree of the system; the coordination control module dynamically switches an emergency instability or preventive damping mode based on G, and generates a coordination control instruction of the phase modifier and the SVG; and the execution feedback module forms a closed loop and optimizes parameters, and realizes efficient response in combination with a layered distributed architecture. According to the invention, deep cooperative control of the two is realized, the disturbance resistance and stability maintenance capability of the power system are improved, and the method is suitable for a power grid with high-proportion renewable energy access.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power system stability control, and particularly relates to a hybrid synchronous condenser fast response coordinated control system with inertia support. BACKGROUND

[0002] With the high proportion of renewable energy access to the power grid, the proportion of traditional synchronous generator sets gradually decreases, which leads to a significant decrease in the inertia level and damping characteristics of the power grid, and the ability of the system to resist disturbances and maintain stability faces severe challenges. As a device that provides inertia support and reactive power regulation, the synchronous condenser can effectively improve the inertia level and short-circuit capacity of the power grid and enhance the transient stability of the system. The static var generator (SVG) plays an important role in voltage support and oscillation suppression due to its fast reactive power response capability.

[0003] However, in the prior art, the control strategies of the synchronous condenser and the SVG are often independently designed and operated. The synchronous condenser usually provides voltage support and power angle damping through its excitation system, and its response speed is relatively slow. It mainly provides inertia support and transient stability in the case of large disturbances in the system. The SVG mainly uses its millisecond-level response speed for fast voltage regulation and low-frequency oscillation suppression. Although the simple strategy of "synchronous condenser providing inertia support and SVG providing fast reactive compensation" can improve the stability of the system to some extent, this fragmented control method has significant defects. In the transient process of the power grid after a severe disturbance, the dynamic interaction of the synchronous condenser and the SVG may have negative effects, such as: The synchronous condenser may cause power angle oscillation when providing inertia support, and the fast reactive compensation of the SVG may exacerbate the oscillation if it is not effectively coordinated with the power angle oscillation. The response speed difference between the synchronous condenser and the SVG is large, and simple superposition control cannot form the best resultant force. In the early stage of fast instability of the system, the inertia effect of the synchronous condenser has not yet fully played a role, and the fast response of the SVG may not be able to provide the most effective support if it lacks awareness of the overall dynamics of the system.

[0004] Therefore, how to realize the deep integration and coordinated control of the synchronous condenser and the SVG so that they can form the best resultant force and avoid control conflicts during power grid disturbances, and intelligently switch control modes according to the overall dynamic coordination degree of the system, is a key technical problem that needs to be solved in the field of power system stability control. SUMMARY

[0005] The purpose of the present application is to solve the technical problem of fragmented control strategies of the synchronous condenser and the static var generator in the prior art. Therefore, we propose a hybrid synchronous condenser fast response coordinated control system with inertia support.

[0006] In order to achieve the above object, the application adopts the following technical scheme: a fast response coordinated control system of a hybrid synchronous phase modifier with inertia support, comprising: A data sensing module is configured to collect dynamic data of multiple key nodes of the power grid in real time through a synchronous phasor measurement unit deployed in the power grid, and clean and preprocess the collected raw data, wherein the dynamic data includes voltage phase , frequency deviation , and active power fluctuation After the raw data is cleaned and preprocessed, it is stored in a high-speed data buffer. A modal evaluation module is configured to calculate a dimensionless evaluation index reflecting the dynamic coordination degree between the synchronous phase modifier group and other generators and loads in the power grid, i.e., a global motion modal coordination coefficient G, based on the preprocessed data output by the data sensing module through an embedded coordination coefficient generation algorithm. A coordinated control module is configured to receive the global motion modal coordination coefficient G output by the modal evaluation module, dynamically decide the control mode according to the numerical value and variation trend of G, and generate differentiated control instructions, including synchronous phase modifier additional excitation control instructions and static var generator additional reactive power reference instructions, to improve the overall stability of the system. An execution feedback module is configured to issue the control instructions to the corresponding execution mechanism, including the synchronous phase modifier excitation system and the SVG control system, and monitor the dynamic response of the power grid after the execution of the control instructions in real time, and send the monitored feedback signals back to the modal evaluation module.

[0007] Preferably, the modal evaluation module comprises: A data window construction unit is configured to obtain a historical data sequence in a time window with a configurable time length T ending at the current time t from the high-speed data buffer, and particularly, construct voltage phase data sequences of all monitoring nodes . A coordination coefficient calculation unit is configured to calculate the coordination coefficient G based on the voltage phase data sequence , and the calculation formula is as follows:

[0008] Wherein represents the standard deviation of the voltage phase difference between all monitoring nodes in the time window T, which is derived from the real-time calculation of the voltage phase data collected by the data sensing module, and is used to quantify the dispersion degree and consistency of the rotor angle distribution of each generator in the system , the greater the value, the more different the motion of each part of the system . ​This represents the frequency deviation of all monitoring nodes within the time window T. The average value is directly derived from the frequency deviation data collected by the data sensing module. This reflects the average deviation of the overall power grid frequency from its rated value; This represents the voltage phase difference within the time window T. The average of the squares, which is obtained from the voltage phase data collected by the data sensing module. The calculation measures the severity of the oscillation angle; a larger value indicates greater oscillation energy and poorer stability. This represents the rate of change of the system's average frequency, i.e., the derivative of the average frequency deviation with respect to time. This data is obtained from the frequency deviation data collected by the data sensing module. Calculated The sequence is obtained by numerical differentiation, which reflects the severity of the overall inertial response and power deficit or excess of the system. The larger the absolute value, the faster the frequency changes and the more unstable the system is. It is a very small constant used as a mathematical safeguard to prevent the denominator from being zero.

[0009] Preferably, the coordination control module includes: The control mode decision unit is used to compare the calculated real-time global motion mode coordination coefficient G with a preset or adaptively adjusted coordination coefficient threshold. Perform real-time comparisons. These values ​​are derived from empirical values ​​obtained through simulation analysis of numerous historical stable and unstable cases. When the judgment When this occurs, it indicates that the system's coordination has dropped to a dangerous level and there is a high risk of instability. The control mode decision unit will then switch the system to the emergency instability control mode. When the judgment When the system is in a relatively stable state, it may require preventative measures to dampen potential oscillations. The control mode decision unit will then switch the system to the preventative damping control mode.

[0010] Preferably, the coordination control module further includes: The emergency instability control command generation unit is used to generate an additional excitation control signal for the i-th synchronous condenser using the following nonlinear function when the system is determined to be in an emergency instability mode. :

[0011] in This is the gain coefficient in emergency mode, an adjustable parameter whose value is derived from offline simulation tuning to ensure that it provides sufficient but not excessive damping torque under the maximum expected disturbance. This indicates the gap between the current system coordination index and the safety threshold; the larger the gap, the stronger the control action required. This data represents the maximum absolute value of the rate of change of frequency across all monitoring nodes, obtained from frequency deviation data collected by the data sensing module. The results are obtained by real-time differentiation and comparison, which are used to capture the frequency changes of the most critical nodes in the current power grid. The frequency variation rate of the local installation node of the i-th synchronous condenser is the frequency deviation data collected from PMU measurements near the synchronous condenser. The information obtained by real-time differentiation reflects the local inertial response. The sign function is used to determine the direction of the damping torque, which is always opposite to the direction of the local frequency change to provide positive damping.

[0012] Preferably, the coordination control module further includes: The preventive damping control command generation unit is used to execute the following subunits when the system is determined to be in preventive damping mode: S1. Dominant Oscillation Mode Identification Subunit: Identifies active power fluctuations collected by the data sensing module. or frequency deviation By using a recursive least squares algorithm for online identification, characteristic parameters of the current dominant low-frequency oscillation mode of the power grid are extracted, including the oscillation frequency. Damping ratio These parameters are derived directly from online spectrum analysis of real-time data; S2.SVG Damping Modulation Command Generation Subunit: Based on the identified dominant mode parameters, it generates additional reactive power reference values ​​for the static var generator. The amplitude A and phase of the command Determined by the following formula:

[0013]

[0014] in, This is the gain coefficient, an adjustable parameter that is tuned through offline simulation. The damping ratio of the dominant oscillation mode is derived from the online mode identification results in step S1. This indicates the degree of damping deficiency in the current mode; the worse the damping, the stronger the damping effect required from the SVG. The current global motion mode coordination coefficients, This means that when the overall coordination of the system is poor, the modulation intensity of the SVG should be appropriately increased; The amplitude estimation of active power fluctuations on critical tie lines is derived from active power data of relevant line PMUs. The real-time calculation reflects the energy scale of the oscillation; For SVG devices at the dominant oscillation frequency The transfer function at point A, and its phase response This is derived from offline frequency response testing of SVG devices or mathematical model calculations based on their controller parameters. This is to compensate for the control phase shift of the SVG itself and to ensure that the final reactive power modulation signal is out of phase with the active power fluctuation signal, thereby providing positive damping; S3. Synchronous condenser damping coordination command generation subunit: In preventive damping mode, it simultaneously generates additional excitation control signals for the synchronous condenser. Its value is:

[0015] in The gain coefficient for adjusting camera damping control is an adjustable parameter; The frequency deviation of the local node of the i-th synchronous condenser originates from the frequency deviation data of that node collected by the data sensing module. ; To determine the system's inertial center frequency deviation, all generator rotor angular velocity or PMU frequency deviation data collected by the data sensing module are analyzed. It is calculated using a weighted average of the inertia constants and represents the overall average motion trend of the system. is the coefficient of the differential term in the proportional-differential coefficients, and it is an adjustable parameter; The rate of change of the difference between the local frequency and the inertial center frequency is obtained by numerically differentiating the sequence of these differences.

[0016] Preferably, the execution feedback module includes: The instruction issuing and execution unit is used to receive control instructions generated by the coordination control module, convert them into specific instruction frames that conform to the field equipment communication protocol, and issue them to the corresponding synchronous condenser excitation system regulator and static var generator controller for execution. The system response monitoring unit is used to continuously monitor the dynamic response of the power grid after the control command is executed. The monitoring data includes a new round of data from the wide-area measurement system, with particular attention to the changing trends of voltage, frequency, power angle and power of key lines. The control effect evaluation unit is used to recalculate the global motion mode coordination coefficient G' based on the new data from the system response monitoring unit after the control action has gone through a preset observation time window T', and compare G' with the G value before the control action to quantitatively evaluate the effectiveness of the control action.

[0017] Preferably, the control effect evaluation unit further includes: The adaptive optimization trigger subunit is used to determine subsequent actions based on the effect evaluation results: If the evaluation finds that G' is significantly improved compared to G, for example, the improvement exceeds the set threshold and can be stabilized at a high level, then the current control strategy parameters are deemed effective and the existing parameter settings are maintained. If the evaluation finds that G' is not significantly improved, the improvement does not reach the threshold, or even continues to deteriorate, then the parameter adaptive optimization sub-unit is triggered. The parameter adaptive optimization subunit, when triggered, optimizes the key adjustable parameters in the coordinated control module based on the difference between G' and G, the current system operating state, and historical control effect records, following a preset gradient descent method. , , and Perform online fine-tuning and optimization, while adjusting the threshold for the collaboration coefficient. Adaptive updates are performed to enable the system to better adapt to changes in power grid operating conditions.

[0018] Preferably, the data sensing module further includes a data quality verification and redundancy management unit, which is used to check the validity of the raw data collected by the PMU, including checking whether the data exceeds the limit, whether a sudden change occurs, and whether the communication is interrupted. It also has a channel redundancy management function, which can automatically switch to the backup channel when the primary communication channel fails.

[0019] Preferably, the system adopts a layered distributed architecture: Some functions of the data sensing module and the execution feedback module are deployed on the plant side, close to the data source and the actuator, to achieve rapid data collection and execution. The control effect evaluation functions of the modal evaluation module, coordination control module, and execution feedback module are deployed on the main station side, collecting data from the entire network for centralized calculation and decision-making.

[0020] The technical effects and advantages of this invention are as follows: In this invention, a synchronous phasor measurement unit is deployed to collect wide-area data such as voltage phase and frequency deviation. After data quality verification and redundancy management, real-time and accurate perception of the entire power grid dynamics is achieved, providing a reliable data foundation for assessment and control. The modal evaluation module calculates the global motion mode coordination coefficient G, realizing a quantitative assessment of the system's dynamic coordination degree and accurately determining the stable state. Based on the G value, the control mode is dynamically switched, enabling synchronous condensers and SVG to coordinate actions, achieving deep equipment cooperation and avoiding independent control conflicts. A closed loop is formed through the execution feedback module, realizing adaptive optimization of control parameters to adapt to changes in power grid operating conditions. A hierarchical distributed architecture is adopted to achieve a balance between real-time performance and global optimization, improving control response speed and coordination efficiency, and ultimately significantly enhancing the power system's ability to resist disturbances and maintain stability. Attached Figure Description

[0021] The disclosure of this invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings, the same reference numerals are used to refer to the same parts: Fig. 1 This is a schematic diagram of the modules of the present invention; Fig. 2 This is a flowchart of the present invention. Detailed Implementation

[0022] It is readily understood that, based on the technical solution of this invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solution of this invention.

[0023] Reference Figs. 1-2 The fast response coordination control system of the hybrid synchronous condenser with inertial support of the present invention mainly includes a data sensing module, a modal evaluation module, a coordination control module and an execution feedback module.

[0024] The data sensing module is responsible for acquiring real-time power grid operating status data. This module collects data through synchronous phasor measurement units (PMUs) deployed at multiple key nodes in the power grid. The PMUs can synchronously acquire dynamic data of the power grid at a high sampling rate, including: voltage phase The voltage phase of each node reflects the real-time changes and is a key indicator for judging the power angle stability of the system.

[0025] Frequency deviation This reflects the degree to which the frequency of each node deviates from its rated value and is an important basis for judging the frequency stability of the system.

[0026] Active power fluctuation It reflects the real-time changes in power flow in the power grid, especially power fluctuations on key tie lines, and is closely related to the system oscillation mode.

[0027] After receiving the raw data collected by the PMU, the data sensing module performs necessary cleaning and preprocessing. Data cleaning includes removing outliers, filling in missing data, filtering, and other operations. Preprocessing may include data format conversion, timestamp alignment, etc. The processed data is stored in a high-speed data buffer for subsequent modules to access and process quickly.

[0028] In addition, the data sensing module also includes a data quality verification and redundancy management unit; this unit performs validity checks on the raw data collected by the PMU: voltage phase, frequency deviation, and active power fluctuation, including: determining whether the data exceeds the reasonable range, determining whether the data has abnormal jumps, and determining whether the communication between the PMU and the data center is normal; when a data quality problem or communication failure is detected, this unit has a channel redundancy management function, that is, it automatically switches to the backup channel when the primary communication channel fails.

[0029] The modal evaluation module is responsible for quantitatively evaluating the overall dynamic coordination level of the power grid. This module receives preprocessed data output from the data sensing module and has a built-in coordination coefficient generation algorithm.

[0030] The modal evaluation module includes a data window construction unit and a synergy coefficient calculation unit.

[0031] Data window construction unit: This unit retrieves historical data sequences from the high-speed data buffer, tracing back to the current time t within a configurable time window of duration T, such as a few seconds to tens of seconds. The main focus of this unit is to construct the voltage phase data sequences of all monitoring nodes. This is because voltage phase is a core indicator reflecting the generator rotor power angle and system synchronization stability; simultaneously, frequency deviation is also obtained. and active power fluctuation The historical sequence.

[0032] Coordination coefficient calculation unit: Based on the voltage phase data sequence provided by the data window construction unit. and frequency deviation Active power fluctuation Based on the data, a dimensionless evaluation index was calculated to quantitatively reflect the degree of dynamic coordination between the synchronous condenser group and other generators and loads in the power grid: the global motion mode coordination coefficient G. This coefficient comprehensively considers the dispersion of the rotor power angle distribution of each generator in the system, the overall frequency deviation of the power grid, the severity of power angle fluctuation, and the average frequency change rate of the system, thus comprehensively reflecting the dynamic coordination and stability of the system.

[0033] The calculation formula is as follows:

[0034] The physical meaning and data source of each parameter are as follows: Voltage phase difference between all monitoring nodes within time window T standard deviation , The voltage phase is defined for any two nodes; this parameter is derived from the voltage phase data collected by the data sensing module. Real-time calculations are used to quantify the dispersion of the power angle distribution of each generator rotor within the system. The larger the value, the more asynchronous the motion of the different parts of the system, and the higher the risk of instability. This represents the frequency deviation of all monitoring nodes within the time window T. The average value is directly derived from the frequency deviation data collected by the data sensing module. This reflects the average deviation of the overall power grid frequency from the rated value. When the system frequency deviates significantly from the rated value, it usually means that the system power is severely unbalanced. This represents the voltage phase difference within the time window T. The average of the squares, which is obtained from the voltage phase data collected by the data sensing module. The calculation measures the severity of the oscillation angle; a larger value indicates greater oscillation energy and poorer stability. This represents the rate of change of the system's average frequency, i.e., the derivative of the average frequency deviation with respect to time. This data is obtained from the frequency deviation data collected by the data sensing module. Calculated The sequence is obtained by numerical differentiation, which reflects the severity of the overall inertial response and power deficit or excess of the system. The larger the absolute value, the faster the frequency changes and the more unstable the system is. For example, a very small constant This is a mathematical protection measure used to prevent the denominator from being zero. The global motion modal coordination coefficient G is a comprehensive dimensionless health indicator. Its numerator combines the work angle dispersion and frequency deviation, and an increase in its value will increase G. The denominator combines the oscillation intensity and frequency change rate, and an increase in its value will decrease G. Therefore, the larger the value of G, the more coordinated the global dynamic response of the system and the better the synchronization stability. The smaller the value of G, the higher the risk of system instability.

[0035] The coordination and control module dynamically decides the control mode based on the global motion mode coordination coefficient G output by the modal evaluation module, and generates differentiated control commands.

[0036] The coordinated control module includes a control mode decision unit, an emergency instability control command generation unit, and a preventive damping control command generation unit.

[0037] Control mode decision unit: Combines the real-time calculated global motion mode coordination coefficient G with the preset or adaptively adjusted coordination coefficient threshold. Comparison, Derived from empirical values ​​obtained from simulation analysis of a large number of historical stable / unstable cases, these values ​​represent the critical point at which the system transitions from a stable state to an unstable state.

[0038] when When the system's coordination drops to a dangerous level and the risk of instability is high, the system switches to emergency instability control mode. In this mode, the control objective is to quickly curb the loss of synchronization of the power angle and prevent the system from collapsing.

[0039] when When the signal is high, it indicates that the system is in a relatively stable state, but there may be potential oscillations or the need for preventative measures to enhance damping. At this point, the system switches to preventative damping control mode. In this mode, the control objective is to suppress low-frequency oscillations, increase system damping, and enhance system robustness.

[0040] Emergency instability control command generation unit: When the control mode decision unit determines that the system has entered an emergency instability mode, this unit generates an additional excitation control signal for the i-th synchronous condenser. This control law is designed to provide additional damping torque by rapidly adjusting the excitation of the synchronous modulator to quickly suppress power angle loss.

[0041] The calculation formula is as follows:

[0042] The physical meaning and data source of each parameter are as follows: This is the gain coefficient in emergency mode, an adjustable parameter whose value is derived from offline simulation tuning to ensure that it provides sufficient but not excessive damping torque under the maximum expected disturbance. This indicates the gap between the current system coordination index and the safety threshold; the larger the gap, the stronger the control action required. This data represents the maximum absolute value of the rate of change of frequency across all monitoring nodes, obtained from frequency deviation data collected by the data sensing module. The results, obtained through real-time differentiation and comparison, are used to capture the frequency changes of the most critical nodes in the current power grid, representing the most severe inertial response challenge of the system. The frequency variation rate of the local installation node of the i-th synchronous condenser is the frequency deviation data collected from PMU measurements near the synchronous condenser. The information obtained by real-time differentiation reflects the local inertial response. The sign function is used to determine the direction of the damping torque, which is always opposite to the direction of the local frequency variation to provide positive damping; Based on the severity of system instability and the acceleration of frequency change at critical nodes The control signal with variable intensity is calculated, and after being limited by the tanh function, reverse damping is applied in the direction of local frequency change to quickly suppress the loss of power angle synchronism.

[0043] Preventive Damping Control Command Generation Unit: When the control mode decision unit determines that the system is in preventive damping mode, this unit generates SVG additional reactive power reference values. and synchronous condenser additional excitation control signal In this mode, the control objective is to suppress low-frequency oscillations and improve system damping.

[0044] This unit first identifies the active power fluctuations collected by the data sensing module by the subunit through the dominant oscillation mode. or frequency deviation The sequence is subjected to real-time Prony analysis or online identification using recursive least squares algorithm, which can extract characteristic parameters of the current dominant low-frequency oscillation mode of the power grid, including oscillation frequency. Damping ratio The parameters are derived directly from online spectrum analysis of real-time data.

[0045] Then, the SVG damping modulation command generation subunit generates additional reactive power reference values ​​for the SVG based on the identified dominant mode parameters. Its amplitude A and phase Determined by the following formula:

[0046]

[0047] The physical meaning and data source of each parameter are as follows: in, This is the gain coefficient, an adjustable parameter that is tuned through offline simulation. The damping ratio of the dominant oscillation mode is derived from the online mode identification results in step S1. This indicates the degree of damping deficiency in the current mode; the worse the damping, the stronger the damping effect required from the SVG. The current global motion mode coordination coefficients, This means that when the overall coordination of the system is poor, the modulation intensity of the SVG should be appropriately increased; The amplitude estimation of active power fluctuations on critical tie lines is derived from active power data of relevant line PMUs. The real-time calculation reflects the energy scale of the oscillation; For SVG devices at the dominant oscillation frequency The transfer function at point A, and its phase response This is derived from offline frequency response testing of SVG devices or mathematical model calculations based on their controller parameters. This is to compensate for the control phase shift of the SVG itself and to ensure that the final reactive power modulation signal is out of phase with the active power fluctuation signal, thereby providing positive damping; This instruction forces the SVG to apply reactive power modulation that is inversely phase to the power fluctuation at the dominant oscillation frequency, absorbing oscillation energy and thus providing precise active damping.

[0048] Meanwhile, in the preventive damping mode, the synchronous condenser damping coordination command generation subunit generates additional excitation control signals for the synchronous condenser. The calculation formula is as follows:

[0049] The physical meaning and data source of each parameter are as follows: The gain coefficient for adjusting camera damping control is an adjustable parameter; The frequency deviation of the local node of the i-th synchronous condenser originates from the frequency deviation data of that node collected by the data sensing module. ; To determine the system's inertial center frequency deviation, all generator rotor angular velocity or PMU frequency deviation data collected by the data sensing module are analyzed. It is calculated using a weighted average of the inertia constants and represents the overall average motion trend of the system. is the coefficient of the differential term in the proportional-differential coefficients, and it is an adjustable parameter; The rate of change of the difference between the local frequency and the inertial center frequency is obtained by numerically differentiating the difference sequence. This control law is based on the classic proportional-derivative control concept, but its control objective is not zero; rather, it aims to keep the rotational speed of the synchronous condenser consistent with the average rotational speed of the system's center of inertia. The proportional term... To reduce the difference between local and average speed, the differential term Used to suppress changes in relative speed, the combination of the two can provide additional damping torque to the system and enhance global synchronization stability.

[0050] The execution feedback module is responsible for sending the control commands generated by the coordination and control module to the field actuators and monitoring the control effect in real time to form a closed-loop control.

[0051] The execution feedback module includes an instruction issuance and execution unit, a system response monitoring unit, and a control effect evaluation unit.

[0052] Command Issuance and Execution Unit: Receives control commands from the coordination control module. and This is converted into command frames conforming to the field device communication protocol and sent to the synchronous condenser excitation system regulator and SVG controller via the communication network for execution. The excitation system regulator then... Adjusting the excitation current of the synchronous condenser changes its output voltage and reactive power, and provides damping torque. The SVG controller, according to... Adjust the reactive power output of the SVG to achieve rapid voltage support and oscillation suppression.

[0053] System Response Monitoring Unit: After control commands are executed, this unit continuously monitors the dynamic response of the power grid. Monitoring data includes the latest voltage phase, frequency deviation, and active power fluctuations collected by the data sensing module. This unit focuses on the changing trends of voltage, frequency, power angle, and power on critical lines.

[0054] Control effectiveness evaluation unit: After the control action has gone through a preset observation time window T', the global motion mode coordination coefficient G' is recalculated based on the new data obtained by the system response monitoring unit. By comparing G' with G before control, the control effectiveness is quantitatively evaluated.

[0055] The control effect evaluation unit also includes an adaptive optimization triggering subunit and a parameter adaptive optimization subunit.

[0056] Adaptive optimization triggering subunit: Decisions on subsequent actions based on effect evaluation results. If G' significantly improves compared to G, for example, if the improvement exceeds a set threshold and remains stable at a high level, the current control strategy parameters are deemed effective, and the existing settings are maintained; if G' does not improve significantly, does not reach the preset threshold, or even deteriorates, the parameter adaptive optimization subunit is triggered.

[0057] Parameter adaptive optimization subunit: Based on the difference between G' and G, the current system operating state, and historical control effect records, it uses a preset gradient descent method or other optimization algorithms to optimize key adjustable parameters in the coordinated control module, such as the emergency mode gain coefficient. SVG gain coefficient Adjusting the camera damping control gain coefficient The differential term coefficients in proportional differential coefficients This allows for online fine-tuning; simultaneously, the sub-unit adaptively updates the cooperation coefficient threshold. This is to better adapt to changes in power grid operating conditions and ensure that the control system is always in optimal working condition.

[0058] The system of this invention adopts a hierarchical distributed architecture; some functions of the data sensing module and the execution feedback module are deployed at the plant / station side, such as the deployment of the PMU and the direct issuance of control commands, to achieve rapid data acquisition and command execution and ensure real-time control; the control effect evaluation functions of the modal evaluation module, the coordinated control module, and the execution feedback module are deployed at the master station side, collecting data from the entire network for centralized calculation and decision-making to achieve global optimization and the operation of complex algorithms; the plant / station and the master station achieve high-speed and reliable communication through the power dispatch data network, together forming a wide-area closed-loop control system.

[0059] This invention, through the aforementioned system and method, achieves intelligent, rapid, and coordinated control of power systems containing synchronous condensers and SVG under abnormal disturbances. By introducing a global motion mode coordination coefficient G, the system can perceive the overall dynamic coordination level of the power grid in real time and intelligently switch control modes accordingly. In case of emergency instability, the synchronous condenser provides strong damping to suppress power angle loss of synchronization; in case of preventative damping, the SVG accurately suppresses low-frequency oscillations, and the synchronous condenser provides auxiliary damping. This deep coordination and closed-loop feedback optimization mechanism significantly improves the power system's ability to resist disturbances and maintain stability, providing a solid guarantee for the safe and stable operation of the power grid under high-proportion renewable energy integration.

[0060] The technical scope of this invention is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the protection scope of this invention.

Claims

1. A fast-response coordinated control system for a hybrid synchronous condenser with inertial support, characterized in that, include: The data sensing module is used to collect dynamic data from multiple key nodes of the power grid in real time through synchronous phasor measurement units deployed in the power grid, and to clean and preprocess the collected raw data. The dynamic data includes voltage phase. Frequency deviation and active power fluctuations After cleaning and preprocessing the collected raw data, it is stored in a high-speed data buffer. The modal evaluation module is used to calculate the dimensionless evaluation index, global motion modal coordination coefficient G, based on the preprocessed data output by the data sensing module and through the built-in coordination coefficient generation algorithm. This index quantifies the dynamic coordination degree between the synchronous condenser group and other generators and loads in the power grid. The coordination control module is used to receive the global motion mode coordination coefficient G output by the modal evaluation module, dynamically decide the control mode according to the magnitude and trend of G, and generate differentiated control commands. The control commands include the synchronous condenser additional excitation control command and the static var generator additional reactive power reference command to improve the overall stability of the system. The execution feedback module is used to send the control command to the corresponding actuator, which includes a synchronous condenser excitation system and an SVG control system, and to monitor the dynamic response of the power grid after the control command is executed in real time, and send the monitored feedback signal back to the modal evaluation module.

2. The fast-response coordinated control system with inertial support for hybrid synchronous condensers according to claim 1, characterized in that, The modal evaluation module includes: The data window construction unit is used to retrieve historical data sequences from the high-speed data buffer, tracing back one configurable duration T from the current time t. Specifically, it constructs the voltage phase data sequences of all monitoring nodes. ; Coordination coefficient calculation unit: used for calculating the voltage phase data sequence The synergy coefficient G is calculated using the following formula: in This represents the voltage phase difference between any two monitoring nodes within the time window T. The standard deviation of the voltage phase data collected by the data sensing module is derived from this value. Real-time calculations are used to quantify the dispersion and consistency of the power angle distribution of each generator rotor within the system. The larger the value, the more asynchronous the movements of different parts of the system; This represents the frequency deviation of all monitoring nodes within the time window T. The average value is directly derived from the frequency deviation data collected by the data sensing module. This reflects the average deviation of the overall power grid frequency from its rated value; This represents the voltage phase difference within the time window T. The average of the squares, which is obtained from the voltage phase data collected by the data sensing module. The calculation measures the severity of the oscillation angle; a larger value indicates greater oscillation energy and poorer stability. This represents the rate of change of the system's average frequency, i.e., the derivative of the average frequency deviation with respect to time. This data is obtained from the frequency deviation data collected by the data sensing module. Calculated The sequence is obtained by numerical differentiation, which reflects the severity of the overall inertial response and power deficit or excess of the system. The larger the absolute value, the faster the frequency changes and the more unstable the system is. It is a very small constant used as a mathematical safeguard to prevent the denominator from being zero.

3. The fast-response coordinated control system with inertial support for hybrid synchronous condensers according to claim 2, characterized in that, The coordination control module includes: The control mode decision unit is used to compare the calculated real-time global motion mode coordination coefficient G with a preset or adaptively adjusted coordination coefficient threshold. Perform real-time comparisons. These values ​​are derived from empirical values ​​obtained through simulation analysis of numerous historical stable and unstable cases. When the judgment When this occurs, it indicates that the system's coordination has dropped to a dangerous level and there is a high risk of instability. The control mode decision unit will then switch the system to the emergency instability control mode. When the judgment When the system is in a relatively stable state, it may require preventative measures to dampen potential oscillations. The control mode decision unit will then switch the system to the preventative damping control mode.

4. The fast-response coordinated control system with inertial support for hybrid synchronous condensers according to claim 3, characterized in that, The coordination control module also includes: The emergency instability control command generation unit is used to generate an additional excitation control signal for the i-th synchronous condenser using the following nonlinear function when the system is determined to be in an emergency instability mode. : in This is the gain coefficient in emergency mode, an adjustable parameter whose value is derived from offline simulation tuning to ensure that it provides sufficient but not excessive damping torque under the maximum expected disturbance. This indicates the gap between the current system coordination index and the safety threshold; the larger the gap, the stronger the control action required. This data represents the maximum absolute value of the rate of change of frequency across all monitoring nodes, obtained from frequency deviation data collected by the data sensing module. The results are obtained by real-time differentiation and comparison, which are used to capture the frequency changes of the most critical nodes in the current power grid. The frequency variation rate of the local installation node of the i-th synchronous condenser is the frequency deviation data collected from PMU measurements near the synchronous condenser. The information obtained by real-time differentiation reflects the local inertial response. The sign function is used to determine the direction of the damping torque, which is always opposite to the direction of the local frequency change to provide positive damping.

5. The fast-response coordinated control system with inertial support for hybrid synchronous condensers according to claim 3, characterized in that, The coordination control module also includes: The preventive damping control command generation unit is used to execute the following subunits when the system is determined to be in preventive damping mode: S1. Dominant Oscillation Mode Identification Subunit: Identifies active power fluctuations collected by the data sensing module. or frequency deviation By using a recursive least squares algorithm for online identification, characteristic parameters of the current dominant low-frequency oscillation mode of the power grid are extracted, including the oscillation frequency. Damping ratio These parameters are derived directly from online spectrum analysis of real-time data; S2.SVG Damping Modulation Command Generation Subunit: Based on the identified dominant mode parameters, it generates additional reactive power reference values ​​for the static var generator. The amplitude A and phase of the command Determined by the following formula: in, This is the gain coefficient, an adjustable parameter that is tuned through offline simulation. The damping ratio of the dominant oscillation mode is derived from the online mode identification results in step S1. This indicates the degree of damping deficiency in the current mode; the worse the damping, the stronger the damping effect required from the SVG. The current global motion mode coordination coefficients, This means that when the overall coordination of the system is poor, the modulation intensity of the SVG should be appropriately increased; The amplitude estimation of active power fluctuations on critical tie lines is derived from active power data of relevant line PMUs. The real-time calculation reflects the energy scale of the oscillation; For SVG devices at the dominant oscillation frequency The transfer function at point A, and its phase response This is derived from offline frequency response testing of SVG devices or mathematical model calculations based on their controller parameters. This is to compensate for the control phase shift of the SVG itself and to ensure that the final reactive power modulation signal is out of phase with the active power fluctuation signal, thereby providing positive damping.

6. The fast-response coordinated control system for a hybrid synchronous condenser with inertial support according to claim 5, characterized in that, The preventive damping control command generation unit further includes: S3. Synchronous condenser damping coordination command generation subunit: In preventive damping mode, it simultaneously generates additional excitation control signals for the synchronous condenser. Its value is: in The gain coefficient for adjusting camera damping control is an adjustable parameter; The frequency deviation of the local node of the i-th synchronous condenser originates from the frequency deviation data of that node collected by the data sensing module. ; To determine the system's inertial center frequency deviation, all generator rotor angular velocity or PMU frequency deviation data collected by the data sensing module are analyzed. It is calculated using a weighted average of the inertia constants and represents the overall average motion trend of the system. is the coefficient of the differential term in the proportional-differential coefficients, and it is an adjustable parameter; The rate of change of the difference between the local frequency and the inertial center frequency is obtained by numerically differentiating the sequence of these differences.

7. The fast-response coordinated control system with inertial support for hybrid synchronous condensers according to claim 1, characterized in that, The execution feedback module includes: The instruction issuing and execution unit is used to receive control instructions generated by the coordination control module, convert them into specific instruction frames that conform to the field equipment communication protocol, and issue them to the corresponding synchronous condenser excitation system regulator and static var generator controller for execution. The system response monitoring unit is used to continuously monitor the dynamic response of the power grid after the control command is executed. The monitoring data includes a new round of data from the wide-area measurement system, with particular attention to the changing trends of voltage, frequency, power angle and power of key lines. The control effect evaluation unit is used to recalculate the global motion mode coordination coefficient G' based on the new data from the system response monitoring unit after the control action has gone through a preset observation time window T', and compare G' with the G value before the control action to quantitatively evaluate the effectiveness of the control action.

8. The fast-response coordinated control system with inertial support for hybrid synchronous condensers according to claim 7, characterized in that, The control effect evaluation unit further includes: The adaptive optimization trigger subunit is used to determine subsequent actions based on the effect evaluation results: If the evaluation finds that G' is significantly improved compared to G, for example, the improvement exceeds the set threshold and can be stabilized at a high level, then the current control strategy parameters are deemed effective and the existing parameter settings are maintained. If the evaluation finds that G' is not significantly improved, the improvement does not reach the threshold, or even continues to deteriorate, then the parameter adaptive optimization sub-unit is triggered. The parameter adaptive optimization subunit, when triggered, optimizes the key adjustable parameters in the coordinated control module based on the difference between G' and G, the current system operating state, and historical control effect records, following a preset gradient descent method. , , and Perform online fine-tuning and optimization, while adjusting the threshold for the collaboration coefficient. Adaptive updates are performed to enable the system to better adapt to changes in power grid operating conditions.

9. The fast-response coordinated control system with inertial support for hybrid synchronous condensers according to claim 1, characterized in that, The data sensing module also includes a data quality verification and redundancy management unit, which is used to check the validity of the raw data collected by the PMU, including checking whether the data exceeds the limit, whether a sudden change occurs, and whether the communication is interrupted. It also has a channel redundancy management function, which can automatically switch to the backup channel when the primary communication channel fails.

10. The fast-response coordinated control system with inertial support for hybrid synchronous condensers according to any one of claims 1-9, characterized in that, Adopting a layered distributed architecture: Some functions of the data sensing module and execution feedback module are deployed on the plant side, close to the data source and actuator, to achieve rapid data collection and execution. The control effect evaluation functions of the modal evaluation module, coordination control module, and execution feedback module are deployed on the main station side, collecting data from the entire network for centralized calculation and decision-making.

Images