An alternating current-direct current hybrid power grid electromagnetic transient simulation process transient potential parameter updating method

Abstract

The application discloses a transient potential parameter updating method in an AC-DC hybrid power grid electromagnetic transient simulation process, belongs to the technical field of AC-DC hybrid power grid electromagnetic transient simulation, and defines a transient potential parameter updating necessity index composed of DC output power, AC output power, wind-solar-thermal output power and total AC-DC output power, collects the above parameters in real time and constructs a time sequence; after normalizing the measurement data, the influence factor of each power parameter on the next time updating demand is calculated in combination with historical data; the next time updating necessity index is predicted by using the current normalized parameter and the influence factor, and the transient potential parameter is dynamically adjusted according to the predicted value; the method fuses historical data and real-time monitoring, solves the precision and efficiency imbalance problem caused by response lag or frequent triggering of the traditional static threshold mechanism through quantitative evaluation and dynamic prediction, and significantly reduces the occupation of computing resource.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electromagnetic transient simulation of AC-DC hybrid power grid, and particularly relates to a transient potential parameter updating method in an electromagnetic transient simulation process of an AC-DC hybrid power grid. BACKGROUND

[0002] The AC-DC hybrid power grid integrates AC system, high-voltage direct current transmission and flexible AC transmission equipment, and its electromagnetic transient process presents high complexity and strong coupling, so that accurate electromagnetic transient simulation becomes a key to research system safety and stability. In the electromagnetic transient simulation process of the AC-DC hybrid power grid, the mainstream scheme currently adopted is a parameter updating strategy based on constant time step or single power deviation threshold. Specifically, one kind of method maintains a fixed small time step in the whole simulation process to ensure high precision; another kind of method monitors system power output, and only when the direct current, active power or reactive power fluctuation exceeds a preset threshold, the calculation frequency of the potential parameter is dynamically adjusted to balance the precision and efficiency. In addition, some researches have carried out parallelization and multi-thread optimization at the implementation level of the simulation platform, and the grid nodes are divided into fragments for parallel solution to speed up the overall simulation process. Overall, these methods have achieved certain results in improving simulation speed and resource utilization, but most of them only rely on real-time measurement values and static thresholds, lacking deep mining and trend prediction of historical data.

[0003] The existing technology is difficult to achieve the best balance between precision and efficiency while reducing the amount of calculation. On the one hand, the trigger mechanism based on static threshold often fails to capture complex coupling effects and nonlinear disturbances in the system due to the limitation of threshold setting, resulting in delay in updating at critical moments and causing error fluctuations in simulation results; on the other hand, when the power grid runs relatively smoothly, the mechanism produces unnecessary calculation due to frequent triggering of the threshold, resulting in waste of computing resources. In addition, most of the existing technologies rely on real-time measurement values and do not fully utilize historical data and power change trends, lacking the ability to predict and adaptively adjust the future state of the system, so the simulation strategy lacks foresight, and it is difficult to meet the application requirements of high precision and low time delay when facing large-scale grid simulation or online real-time monitoring.

[0004] Therefore, the existing technology needs a new technical solution to solve the above problems. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a transient potential parameter updating method in an electromagnetic transient simulation process of an AC-DC hybrid power grid, which overcomes the technical problems of lack of quantitative evaluation and dynamic prediction of transient potential parameter updating demand, and difficulty in balancing efficiency and precision in the prior art; and can improve the efficiency of transient potential parameter updating in the electromagnetic transient simulation process of the AC-DC hybrid power grid and reduce the occupation of computing resources.

[0006] A method for updating transient potential parameters in an electromagnetic transient simulation process of an AC-DC hybrid power grid, comprising the following steps, and the following steps are sequentially performed:

[0007] Step one: define the index parameters related to the necessity index of updating transient potential parameters in the electromagnetic transient simulation process of the AC-DC hybrid power grid, which are referred to as index parameters, including DC output power, AC output power, wind-solar-thermal output power, and total AC-DC output power;

[0008] Step two: measure the index parameters in step one, and establish a time series of the index parameters related to the necessity index of updating transient potential parameters in the electromagnetic transient simulation process of the AC-DC hybrid power grid according to the obtained measurement values; normalize the time series to obtain normalized parameters;

[0009] Step three: calculate the influence factor of each power parameter on the updating demand at the next moment in combination with historical data;

[0010] Step four: predict the updating necessity index at the next moment by using the normalized parameters and the influence factor, and obtain the predicted value of the updating necessity index;

[0011] Step five: adjust the transient potential parameters in the electromagnetic transient simulation process of the AC-DC hybrid power grid at the next moment according to the predicted value of the updating necessity index at the next moment.

[0012] The necessity index of updating transient potential parameters in the electromagnetic transient simulation process of the AC-DC hybrid power grid is:

[0013] ,

[0014] wherein, is the moment of n fixed time intervals, wherein n is a natural number , s is the s-th moment, s is a natural number, and ; is the DC output power of the electromagnetic transient simulation of the AC-DC hybrid power grid at the moment; is the AC output power of the electromagnetic transient simulation of the AC-DC hybrid power grid at the moment; is the wind-solar-thermal output power of the electromagnetic transient simulation of the AC-DC hybrid power grid at the moment; is the total AC-DC output power of the electromagnetic transient simulation of the AC-DC hybrid power grid at the moment; , are respectively The maximum and minimum DC output power values ​​in the electromagnetic transient simulation of a hybrid AC / DC power grid at any given time. , They are respectively The maximum and minimum values ​​of AC output power in the electromagnetic transient simulation of a hybrid AC / DC power grid at any time. , They are respectively Real-time electromagnetic transient simulation of AC / DC hybrid power grid, showing the maximum and minimum output power of wind, solar and thermal power. , They are respectively The maximum and minimum values ​​of total AC and DC output power in the electromagnetic transient simulation of the AC / DC hybrid power grid at any time.

[0015] The time series of the parameters related to the update necessity index is as follows:

[0016] ,

[0017] Normalization of the time series is performed as follows:

[0018] ,

[0019] In the formula, for Real-time electromagnetic transient simulation of DC output power in AC / DC hybrid power grid for Normalized value of DC output power in electromagnetic transient simulation of AC / DC hybrid power grid at any time; for Real-time electromagnetic transient simulation of AC / DC hybrid power grid, AC output power. for Normalized value of AC output power in electromagnetic transient simulation of AC / DC hybrid power grid at any time; for Real-time electromagnetic transient simulation of wind, solar, and thermal power output power in a hybrid AC / DC power grid for Normalized values ​​of wind, solar and thermal power output power in real-time electromagnetic transient simulation of AC / DC hybrid power grid. for The total AC and DC output power in the electromagnetic transient simulation of the AC / DC hybrid power grid at any time. for Normalized values ​​of total AC and DC output power in electromagnetic transient simulation of AC / DC hybrid power grid at any time.

[0020] The formulas for calculating the influence factors of each power parameter on the update demand at the next moment are as follows:

[0021] ,

[0022] In the formula, The influence factor of the necessity index of DC output power on the update of transient potential parameters in the electromagnetic transient simulation process of AC / DC hybrid power grid at the next moment; The influence factor of the necessity index for updating the transient potential parameters of the AC / DC hybrid power grid electromagnetic transient simulation process at the next moment is used to determine the impact of the AC output power on the transient simulation process of the AC / DC hybrid power grid electromagnetic transient simulation. The influence factor of the necessity index for updating the transient potential parameters of the AC / DC hybrid power grid electromagnetic transient simulation process in the next moment is determined by the output power of wind, solar and thermal power in the electromagnetic transient simulation of the AC / DC hybrid power grid. The index of influence factors on the necessity of updating transient potential parameters in the electromagnetic transient simulation process of AC / DC hybrid power grids at the next moment is calculated based on the total AC / DC output power of the total AC / DC output power.

[0023] The formula for calculating the predicted value of the update necessity index is as follows:

[0024] .

[0025] The formula for adjusting the transient potential parameters in the electromagnetic transient simulation process of the AC / DC hybrid power grid at the next moment is:

[0026] ,

[0027] In the formula, This represents the transient potential parameters in the electromagnetic transient simulation process of the AC / DC hybrid power grid at the next moment; if If the value is greater than or equal to 0.562, then the transient potential parameter requirement for the electromagnetic transient simulation process of the AC / DC hybrid power grid at the next moment is relatively high, and the transient potential parameter for the electromagnetic transient simulation process of the AC / DC hybrid power grid needs to be increased; if If the value is less than 0.562, the transient potential parameter requirement for the electromagnetic transient simulation process of the AC / DC hybrid power grid at the next moment will remain unchanged.

[0028] Through the above design scheme, the present invention can bring the following beneficial effects: a method for updating transient potential parameters in the electromagnetic transient simulation process of AC / DC hybrid power grid, which predicts the update requirements of transient potential parameters in the electromagnetic transient simulation process of AC / DC hybrid power grid at the next moment, and adjusts the transient potential parameters at the next moment according to the prediction results, thereby reducing the occupation of computing resources. Attached Figure Description

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0030] Figure 1 This is a schematic diagram of the transient potential parameter update method in the electromagnetic transient simulation process of an AC / DC hybrid power grid according to the present invention. Detailed Implementation

[0031] A method for updating transient potential parameters in the electromagnetic transient simulation process of an AC / DC hybrid power grid, such as... Figure 1 As shown: By defining a transient potential parameter update necessity index composed of DC output power, AC output power, wind, solar, and thermal power output power, and total AC and DC output power, the above parameters are collected in real time and a time series is constructed; after normalizing the measured data, the influence factor of each power parameter on the update requirement at the next moment is calculated by combining historical data; the update necessity index at the next moment is predicted using the current normalized parameters and influence factors, and the transient potential parameters are dynamically adjusted according to the predicted value: when the update necessity index... The method increases the parameter update frequency to ensure accuracy when necessary, otherwise maintains the original strategy to avoid redundant calculations. It integrates historical data with real-time monitoring, and through quantitative evaluation and dynamic prediction, solves the accuracy-efficiency imbalance problem caused by response lag or frequent triggering in traditional static threshold mechanisms, significantly reducing computing resource consumption.

[0032] Specifically, the following steps are included:

[0033] Step 1: Define the necessity index for updating transient potential parameters in the electromagnetic transient simulation process of AC / DC hybrid power grids. As shown in formula (1):

[0034] (1)

[0035] In the formula, Let n be the times at fixed time intervals, where n is a natural number. s is the s-th time, s is a natural number, and ; for Real-time electromagnetic transient simulation of DC output power in AC / DC hybrid power grid; for Real-time electromagnetic transient simulation of AC / DC hybrid power grid, AC output power; for Real-time electromagnetic transient simulation of wind, solar and thermal power output power in AC / DC hybrid power grid; for Electromagnetic transient simulation of AC / DC hybrid power grid: total AC and total DC output power at all times; , They are respectively The maximum and minimum DC output power values ​​in the electromagnetic transient simulation of a hybrid AC / DC power grid at any given time. , They are respectively The maximum and minimum values ​​of AC output power in the electromagnetic transient simulation of a hybrid AC / DC power grid at any time. , They are respectively Maximum and minimum of wind, solar and thermal power output in AC / DC hybrid power grid electromagnetic transient simulation at time t; , Maximum and minimum of wind, solar and thermal power output in AC / DC hybrid power grid electromagnetic transient simulation at time t; Maximum and minimum of total AC and DC power output in AC / DC hybrid power grid electromagnetic transient simulation at time t.

[0036] Step 2: Measurement The parameters related to the index of necessity of transient potential parameter updating in AC / DC hybrid power grid electromagnetic transient simulation process are measured, and the time series of the parameters related to the index of necessity of transient potential parameter updating in AC / DC hybrid power grid electromagnetic transient simulation process are established according to the measured values as shown in formula (2):

[0037] (2)

[0038] Step 3: Normalization processing of the measured data of the parameters related to the index of necessity of transient potential parameter updating in AC / DC hybrid power grid electromagnetic transient simulation process is performed as shown in formula (3):

[0039] (3)

[0040] In the formula, is the normalized value of DC power output in AC / DC hybrid power grid electromagnetic transient simulation at time t; is the normalized value of AC power output in AC / DC hybrid power grid electromagnetic transient simulation at time t; is the normalized value of wind, solar and thermal power output in AC / DC hybrid power grid electromagnetic transient simulation at time t; is the normalized value of total AC and DC power output in AC / DC hybrid power grid electromagnetic transient simulation at time t.

[0041] Step 4: The influence factor of the historical data of the parameters related to the index of necessity of transient potential parameter updating in AC / DC hybrid power grid electromagnetic transient simulation process on the index of necessity of transient potential parameter updating in AC / DC hybrid power grid electromagnetic transient simulation process at next time t is calculated as shown in formula (4):

[0042] (4)

[0043] In the formula, is the influence factor of DC power output in AC / DC hybrid power grid electromagnetic transient simulation on the index of necessity of transient potential parameter updating in AC / DC hybrid power grid electromagnetic transient simulation process at next time t; is the influence factor of AC power output in AC / DC hybrid power grid electromagnetic transient simulation on the index of necessity of transient potential parameter updating in AC / DC hybrid power grid electromagnetic transient simulation process at next time t;​​​​ The influence factor of the necessity index for updating the transient potential parameters of the AC / DC hybrid power grid electromagnetic transient simulation process in the next moment is determined by the output power of wind, solar and thermal power in the electromagnetic transient simulation of the AC / DC hybrid power grid. The index of influence factors on the necessity of updating transient potential parameters in the electromagnetic transient simulation process of AC / DC hybrid power grids at the next moment is calculated based on the total AC / DC output power of the total AC / DC output power.

[0044] Step 5: Calculate the predicted value of the necessity index for updating the transient potential parameters in the electromagnetic transient simulation process of the AC / DC hybrid power grid at the next moment, as shown in equation (5):

[0045] (5)

[0046] Step 6: [Regarding...] Transient potential parameters during electromagnetic transient simulation of AC / DC hybrid power grid The transient potential parameters of the AC / DC hybrid power grid electromagnetic transient simulation process are adjusted according to the predicted value of the necessity index for updating the transient potential parameters in the next moment, as shown in Equation (6).

[0047] (6)

[0048] In the formula, This represents the transient potential parameters of the AC / DC hybrid power grid during the electromagnetic transient simulation process at the next moment. From equation (6), it can be seen that if the obtained... If the value is greater than or equal to 0.562, then the transient potential parameter requirement for the electromagnetic transient simulation process of the AC / DC hybrid power grid at the next moment is considered high, and the transient potential parameter for the electromagnetic transient simulation process of the AC / DC hybrid power grid needs to be increased; if the obtained value is... If the value is less than 0.562, it is assumed that the transient potential parameter requirement of the electromagnetic transient simulation process of the AC / DC hybrid power grid at the next moment will remain unchanged, and the transient potential parameter of the electromagnetic transient simulation process of the AC / DC hybrid power grid will remain unchanged.

Claims

1. A method for updating transient potential parameters in an electromagnetic transient simulation process of an AC / DC hybrid power grid, characterized in that: Comprising the following steps, And the following steps are sequentially carried out: Step one: define the AC / DC hybrid power grid electromagnetic transient simulation process transient potential parameter update necessity index related parameters, referred to as index parameters, including DC output power, AC output power, wind, light and fire output power and total AC / DC output power; Step two: measure T s At the moment, the index parameter is measured in step one, and the related parameter time series of the transient potential parameter update necessity index of the electromagnetic transient simulation process of the AC-DC hybrid power grid is established according to the obtained measurement value; the time series is normalized to obtain the normalized parameter; Step three: calculate the influence factor of each power parameter on the next time update demand combined with historical data; Step four: predict the update necessity index of the next time using the normalized parameters and the influence factor to obtain the update necessity index prediction value; Step five: adjust the AC / DC hybrid power grid electromagnetic transient simulation process transient potential parameter of the next time according to the update necessity index prediction value of the next time AC / DC hybrid power grid electromagnetic transient simulation process transient potential parameter; The AC-DC hybrid power grid electromagnetic transient simulation process transient potential parameter update necessity index μ zs is: In the formula, T1, T2, …, T s ,...,T n are time points of n fixed time intervals, wherein n is a natural number n ∈ 1, 2, …, s is the s th time point, s is a natural number, and s ∈ {1, 2, …, n}; is the DC output power of the AC-DC hybrid power grid at T s is the AC output power of the AC-DC hybrid power grid at T s is the wind-solar-thermal output power of the AC-DC hybrid power grid at T s is the total AC and DC output power of the AC-DC hybrid power grid at TsD zd,max is the DC output power of the AC-DC hybrid power grid at T s ,...,T n is the wind-solar-thermal output power of the AC-DC hybrid power grid at T zs,max is the AC output power of the AC-DC hybrid power grid at T s ,...,T n is the total AC and DC output power of the AC-DC hybrid power grid at T​​​ 2. The method of claim 1, wherein the method is characterized by: The time series of the update necessity index related parameters is: The normalized processing of the time series is: In the formula, T is T s DC output power of the AC-DC hybrid power grid at time T, T is T s Normalized value of the DC output power of the AC-DC hybrid power grid at time T; AC output power of the AC-DC hybrid power grid at time T, T is T s Normalized value of the AC output power of the AC-DC hybrid power grid at time T; T is T s T, wind-solar-thermal output power of the AC-DC hybrid power grid at time T, T is T s Normalized value of the wind-solar-thermal output power of the AC-DC hybrid power grid at time T; T is T s Total AC and DC output power of the AC-DC hybrid power grid at time T, T is T s Normalized value of the total AC and DC output power of the AC-DC hybrid power grid at time T, Z zl,max , Z zl,min are respectively T1, T2,..., T s ,..., T n Maximum and minimum values of the DC output power of the AC-DC hybrid power grid at time T; J jl,max , J jl,min are respectively T1, T2,..., T s ,..., T n Maximum and minimum values of the AC output power of the AC-DC hybrid power grid at time T; D zd,min are respectively T1, T2,..., T s ,..., T n Minimum value of the wind-solar-thermal output power of the AC-DC hybrid power grid at time T; R zs,min are respectively T1, T2,..., T s ,..., T n Minimum value of the total AC and DC output power of the AC-DC hybrid power grid at time T.

3. The method of claim 1, wherein the method is characterized by: The calculation formula of the influence factor of each power parameter on the next time update demand is: In the formula, is the influence factor of DC output power of electromagnetic transient simulation of AC / DC hybrid power grid on the necessity index of transient potential parameter update of next time electromagnetic transient simulation process of AC / DC hybrid power grid; is the influence factor of AC output power of electromagnetic transient simulation of AC / DC hybrid power grid on the necessity index of transient potential parameter update of next time electromagnetic transient simulation process of AC / DC hybrid power grid; is the influence factor of wind-solar-thermal output power of electromagnetic transient simulation of AC / DC hybrid power grid on the necessity index of transient potential parameter update of next time electromagnetic transient simulation process of AC / DC hybrid power grid; is the influence factor of total AC and total DC output power of electromagnetic transient simulation of AC / DC hybrid power grid on the necessity index of transient potential parameter update of next time electromagnetic transient simulation process of AC / DC hybrid power grid.

4. The method of claim 1, wherein the method is characterized by: The update necessity index prediction value calculation formula is: 。 5. The method of claim 1, wherein the method is a method for updating transient potential parameters in an electromagnetic transient simulation process of an AC / DC hybrid power grid. The next time AC / DC hybrid power grid electromagnetic transient simulation process transient potential parameter adjustment formula is: In the formula, represents the transient state potential parameter of the next time electromagnetic transient simulation process of the AC-DC hybrid power grid; if is greater than or equal to 0.562, the transient state potential parameter of the electromagnetic transient simulation process of the AC-DC hybrid power grid is increased; if is less than 0.562, the transient state potential parameter of the electromagnetic transient simulation process of the AC-DC hybrid power grid remains unchanged.

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