Low-frequency oscillation source-load parameter combination identification method and system based on damping ratio sensitivity

Abstract

This invention relates to the field of power system condition monitoring technology, and is a method and system for identifying source-load parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity. The system includes a simulation model establishment unit, a new energy unit selection unit, a motor load selection unit, and a source-load parameter combination identification unit. It establishes a power system simulation model containing multiple new energy units and multiple motor loads and calculates the initial system damping ratio. By calculating the damping ratio sensitivity, this invention identifies the new energy units, motor loads, and source-load parameter combinations that are most sensitive to power system oscillations, providing a reference for improving the damping ratio and suppressing oscillations. This method can simultaneously identify parameter combinations of new energy units and motor loads, reflecting the synergistic effect of both the source and load sides on the system damping ratio and oscillations. Compared with the identification of single power source or load parameters, this method has guiding significance for locating and suppressing low-frequency system oscillations.

Description

Technical Field

[0001] This invention relates to the field of power system condition monitoring technology, and in particular to a method and system for identifying source-load parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity. Background Technology

[0002] With the increasing proportion of renewable energy connected to the grid, the safe and stable operation of the power system faces severe challenges. Renewable energy units have relatively weak disturbance rejection capabilities, and the nonlinear characteristics of motor-type loads further affect the dynamic characteristics of the system. When the output power fluctuations of renewable energy are synchronized with load fluctuations, it may cause severe voltage or frequency fluctuations, triggering low-frequency oscillations in the power system. Identifying and locating the source-load parameters most sensitive to suppressing low-frequency oscillations is particularly important. However, existing parameter identification methods mainly focus on identifying single power source or load parameters, making it difficult to reflect the synergistic effects between sources and loads.

[0003] To address the aforementioned issues, this invention provides a method for identifying source-load parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity. By calculating the damping ratio sensitivity, the method identifies the new energy generating units, motor-type loads, and source-load parameter combinations that are most sensitive to power system oscillations, providing a reference for improving the damping ratio and suppressing oscillations. Summary of the Invention

[0004] This invention provides a method for identifying source-load parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity, which overcomes the shortcomings of the prior art. It can effectively solve the problem that existing methods for identifying low-frequency oscillations in power systems using a single power source or load parameter cannot reflect the synergistic effect between the source and load.

[0005] To address the above problems, one of the technical solutions of this invention is achieved through the following method: a method for identifying source-load parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity, comprising: Establish a power system simulation model containing multiple new energy generating units and multiple motor-type loads, and calculate the initial damping ratio of the system; Based on the initial damping ratio of the system, the average damping ratio sensitivity of each new energy unit is calculated, and the new energy unit with the largest average damping ratio sensitivity is selected. Based on the initial damping ratio of the system, the average damping ratio sensitivity of each type of motor load is calculated, and the type of motor load with the highest average damping ratio sensitivity is selected. A source-load parameter set is constructed using the new energy generating unit with the highest average damping ratio sensitivity and the motor load with the highest average damping ratio sensitivity. Source-load parameter sensitivity calculations are performed to identify the source-load parameter combination that is most sensitive to suppressing low-frequency oscillations.

[0006] The above-mentioned establishment of a power system simulation model containing multiple new energy generating units and multiple motor-type loads, and calculation of the initial damping ratio of the system, includes: Establish a power system simulation model containing multiple new energy generating units and multiple motor-type loads; Set the component parameters for new energy generator units and motor-type loads as baseline parameters; Based on the baseline parameters, the initial damping ratio of the power system is calculated using the small-disturbance stability analysis method. The calculation method is as follows: , In the formula, It is the real part of the eigenvalues ​​of the system state matrix under the reference parameters; It is the imaginary part of the eigenvalues ​​of the system state matrix under the reference parameters.

[0007] The above calculation, based on the initial damping ratio of the system, calculates the average damping ratio sensitivity of each new energy unit and selects the new energy unit with the highest average damping ratio sensitivity; including: Calculate the active power-damping ratio sensitivity by changing the active power of each new energy unit separately. : , In the formula, To standardize the active power regulation step size for new energy generating units, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the active power parameter of the renewable energy unit. The initial damping ratio of the power system; The active power of the new energy units in the benchmark parameters; Calculate the voltage-damping ratio sensitivity by changing the terminal voltage of each new energy unit separately. : , In the formula, To ensure a uniform voltage regulation step size, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the terminal voltage parameter of the new energy unit. The initial damping ratio of the power system. It refers to the terminal voltage of the new energy unit in the benchmark parameters; Calculate the average damping ratio sensitivity of each new energy unit. : , Select the new energy unit with the largest value, denoted as . .

[0008] The above calculation, based on the initial damping ratio of the system, calculates the average damping ratio sensitivity for each type of motor load, and selects the motor load with the highest average damping ratio sensitivity; including: Calculate the active power-damping ratio sensitivity by changing the active power of each type of motor load separately. : , In the formula, To achieve a unified active power regulation step size, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the active power parameter of the load. The initial damping ratio of the power system; It is the active power of the load in the baseline parameters; Calculate the load structure-damping ratio sensitivity by changing the load structure for each type of motor load. : , In the formula, To ensure a uniform load structure adjustment step size, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the load structure parameter. The initial damping ratio of the power system. It is the load structure in the reference parameters; Calculate the average damping ratio sensitivity for each type of motor load. : , Select the motor type load with the largest value, and denote it as... .

[0009] The above-mentioned source-load parameter set is constructed by the new energy unit with the highest average damping ratio sensitivity and the motor load with the highest average damping ratio sensitivity. Source-load parameter sensitivity calculations are then performed to identify the source-load parameter combination most sensitive to suppressing low-frequency oscillations, including: statistics and Adjustable parameters form a parameter set. and ,in These are the motor inertia time constant, damping coefficient, and voltage outer loop proportional-integral gain of the new energy generator unit. It is the per-unit value of the bus voltage of the load, and the ratio of the constant impedance component to the constant power component in the load; Select simultaneously each time and Using one parameter from each source-load group, the sensitivity of the source-load parameter set to the power grid system damping ratio is calculated using the sensitivity analysis gradient method. ; choose The source-load parameter set with the largest numerical value is denoted as This allows us to identify the source-charge parameter combination that is most sensitive to suppressing low-frequency oscillations.

[0010] The above simultaneous selection each time and Using one parameter from each source-load group, the sensitivity of the source-load parameter set to the power grid system damping ratio is calculated using the sensitivity analysis gradient method. ,include: The calculation method is as follows: , In the formula, For the combined parameters, the first r Adjustment step size under each gradient, The combined parameters are in the first... r Damping ratio at each gradient t This refers to the total number of gradients.

[0011] The second technical solution of this invention is achieved through the following method: a source-load parameter combination identification system for suppressing low-frequency oscillations based on damping ratio sensitivity, using a method for identifying source-load parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity, comprising: The simulation model building unit establishes a power system simulation model containing multiple new energy generating units and multiple motor-type loads, and calculates the initial damping ratio of the system. The new energy unit selection unit calculates the average damping ratio sensitivity of each new energy unit based on the initial damping ratio of the system, and selects the new energy unit with the highest average damping ratio sensitivity. The motor load selection unit calculates the average damping ratio sensitivity of each motor load based on the initial damping ratio of the system, and selects the motor load with the highest average damping ratio sensitivity. The source-load parameter combination identification unit constructs a source-load parameter set by constructing the new energy unit with the highest average damping ratio sensitivity and the motor load with the highest average damping ratio sensitivity, performs source-load parameter sensitivity calculation, and identifies the source-load parameter combination that is most sensitive to suppressing low-frequency oscillations.

[0012] Compared with the prior art, the present invention has the following advantages: The present invention provides a method and system for identifying source-load parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity. By calculating the damping ratio sensitivity, it identifies the new energy generating units, electric motor loads, and source-load parameter combinations that are most sensitive to the impact of power system oscillations. This provides a reference for improving the damping ratio and suppressing oscillations. The method of the present invention can simultaneously identify parameter combinations of new energy generating units and electric motor loads, and can reflect the synergistic influence of both the source and load sides on the system damping ratio and oscillations. Compared with the identification of a single power source or load parameter, this method has guiding significance for locating and suppressing low-frequency oscillations in the system. Attached Figure Description

[0013] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0014] Figure 1 This is a flowchart of the method in Embodiment 1 of the present invention.

[0015] Figure 2 This is a system structure block diagram of Embodiment 2 of the present invention.

[0016] Figure 3 This is a schematic diagram of the four-machine two-load reference model in Embodiment 3 of the present invention. Detailed Implementation

[0017] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.

[0018] Example 1: As Figure 1 As shown, this invention discloses a method for identifying source-charge parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity, comprising: S101, Establish a power system simulation model containing multiple new energy generating units and multiple motor-type loads and calculate the initial damping ratio of the system; S102, Based on the initial damping ratio of the system, calculate the average damping ratio sensitivity of each new energy unit, and select the new energy unit with the largest average damping ratio sensitivity. S103, Based on the initial damping ratio of the system, calculate the average damping ratio sensitivity of each type of motor load, and select the type of motor load with the highest average damping ratio sensitivity; S104 constructs a source-load parameter set by using the new energy unit with the highest average damping ratio sensitivity and the motor load with the highest average damping ratio sensitivity, performs source-load parameter sensitivity calculation, and identifies the source-load parameter combination that is most sensitive to suppressing low-frequency oscillations.

[0019] In step S101 above, establishing a power system simulation model containing multiple new energy generating units and multiple motor-type loads and calculating the initial damping ratio of the system includes: Establish a power system simulation model containing multiple new energy generating units and multiple motor-type loads; Set the component parameters for new energy generator units and motor-type loads as baseline parameters; Based on the baseline parameters, the initial damping ratio of the power system is calculated using the small-disturbance stability analysis method. The calculation method is as follows: (1) In the formula, It is the real part of the eigenvalues ​​of the system state matrix under the reference parameters; It is the imaginary part of the eigenvalues ​​of the system state matrix under the reference parameters.

[0020] In step S102 above, based on the initial damping ratio of the system, the average damping ratio sensitivity of each new energy unit is calculated, and the new energy unit with the highest average damping ratio sensitivity is selected; including: Calculate the active power-damping ratio sensitivity by changing the active power of each new energy unit separately. : (2) In the formula, To standardize the active power regulation step size for new energy generating units, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the active power parameter of the renewable energy unit. The initial damping ratio of the power system; The active power of the new energy units in the benchmark parameters; Calculate the voltage-damping ratio sensitivity by changing the terminal voltage of each new energy unit separately. : (3) In the formula, To ensure a uniform voltage regulation step size, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the terminal voltage parameter of the new energy unit. The initial damping ratio of the power system. It refers to the terminal voltage of the new energy unit in the benchmark parameters; Calculate the average damping ratio sensitivity of each new energy unit. : (4) Select the new energy unit with the largest value, denoted as . .

[0021] In step S103 above, based on the initial damping ratio of the system, the average damping ratio sensitivity of each type of motor load is calculated, and the type of motor load with the highest average damping ratio sensitivity is selected; including: Calculate the active power-damping ratio sensitivity by changing the active power of each type of motor load separately. : (5) In the formula, To achieve a unified active power regulation step size, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the active power parameter of the load. The initial damping ratio of the power system; It is the active power of the load in the baseline parameters; Calculate the load structure-damping ratio sensitivity by changing the load structure for each type of motor load. : (6) In the formula, To ensure a uniform load structure adjustment step size, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the load structure parameter. The initial damping ratio of the power system. It is the load structure in the reference parameters; Calculate the average damping ratio sensitivity for each type of motor load. : (7) Select the motor type load with the largest value, and denote it as... .

[0022] in, The damping ratio is calculated using small-disturbance stability analysis after only adjusting the active power of the new energy generator. The damping ratio is calculated using small-disturbance stability analysis after only adjusting the terminal voltage of the new energy unit. The damping ratio calculated using small-disturbance stability analysis after adjusting only the active power parameter of the load is as follows: The damping ratio is calculated using the small disturbance stability analysis method after only adjusting the load structure parameter. The above damping ratios are all quantitatively calculated again using the same calculation method as the initial damping ratio of the power system, under the condition that the active power parameters of the new energy unit are disturbed while the other reference parameters remain unchanged.

[0023] In step S104 above, a source-load parameter set is constructed using the new energy generator unit with the highest average damping ratio sensitivity and the motor load with the highest average damping ratio sensitivity. Source-load parameter sensitivity calculations are then performed to identify the source-load parameter combination most sensitive to suppressing low-frequency oscillations, including: statistics and Adjustable parameters form a parameter set. and ,in These are the motor inertia time constant, damping coefficient, and voltage outer loop proportional-integral gain of the new energy generator unit. It is the per-unit value of the bus voltage of the load, and the ratio of the constant impedance component to the constant power component in the load; Select simultaneously each time and Using one parameter from each source-load group, the sensitivity of the source-load parameter set to the power grid system damping ratio is calculated using the sensitivity analysis gradient method. ; choose The source-load parameter set with the largest numerical value is denoted as This allows us to identify the source-charge parameter combination that is most sensitive to suppressing low-frequency oscillations.

[0024] Among them, each time simultaneously select and Using one parameter from each source-load group, the sensitivity of the source-load parameter set to the power grid system damping ratio is calculated using the sensitivity analysis gradient method. The calculation method is as follows: (8) In the formula, For the combined parameters, the first r Adjustment step size under each gradient, The combined parameters are in the first... r Damping ratio at each gradient t This refers to the total number of gradients.

[0025] Example 2: As Figure 2 As shown, this invention discloses a source-load parameter combination identification system for suppressing low-frequency oscillations based on damping ratio sensitivity, using a method for identifying source-load parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity, including: The simulation model building unit establishes a power system simulation model containing multiple new energy generating units and multiple motor-type loads, and calculates the initial damping ratio of the system. The new energy unit selection unit calculates the average damping ratio sensitivity of each new energy unit based on the initial damping ratio of the system, and selects the new energy unit with the highest average damping ratio sensitivity. The motor load selection unit calculates the average damping ratio sensitivity of each motor load based on the initial damping ratio of the system, and selects the motor load with the highest average damping ratio sensitivity. The source-load parameter combination identification unit constructs a source-load parameter set by constructing the new energy unit with the highest average damping ratio sensitivity and the motor load with the highest average damping ratio sensitivity, performs source-load parameter sensitivity calculation, and identifies the source-load parameter combination that is most sensitive to suppressing low-frequency oscillations.

[0026] Example 3: This embodiment of the invention is based on a PSASP-built four-machine, two-load power system benchmark model. The four machines refer to two synchronous generators and two doubly-fed wind turbines; both loads are motor-type loads. A power grid wiring diagram is attached. Figure 3 As shown in the figure, the baseline model has a total output of 221MW from four generators, with two new energy units each outputting 45MW, representing 40.72% of the total output. The per-unit voltage of both generators is 1.013. The two loads each consume 107MW of active power, with a constant impedance component to constant power component ratio of 3 / 4. The motor inertia time constant of the new energy units is 4.92s, the per-unit damping coefficient is 0.1, and the voltage outer loop proportional-integral gain is 18. The per-unit voltage of the motor-type loads is 0.97, and the ratio of constant impedance to constant power components in the load is 3 / 4. The initial damping ratio of the baseline model is 1.91%.

[0027] First, the active power of each doubly-fed wind turbine is changed individually, with the active power adjustment step size set to 5MW, and the active power-damping ratio sensitivity is calculated. Next, the terminal voltage of each doubly-fed wind turbine was changed, with a voltage adjustment step size of 20V, and the voltage-damping ratio sensitivity was calculated. Finally, the average damping ratio sensitivity of each doubly-fed wind turbine unit was calculated. The calculation results are shown in Table 1. (Selection) The doubly fed wind turbine with the largest numerical value is SCIG2, denoted as .

[0028] First, change the active power of each type of motor load separately, setting the active power adjustment step size to 5MW, and calculate the active power-damping ratio sensitivity. Secondly, the load structure of each type of motor load is changed, that is, the ratio of constant impedance component to constant power component ( K ), K The adjustment step size is set to 0.2; the load structure-damping ratio sensitivity is calculated. Finally, the average damping ratio sensitivity of each type of motor load is calculated. The calculation results are shown in Table 2. (Selection) The largest motor-type load, Load1, is denoted as .

[0029] statistics and Adjustable parameters form a parameter set. and ,in These are the motor inertia time constant, damping coefficient, and voltage outer loop proportional-integral gain of the new energy generator unit. It is the per-unit value of the bus voltage of the load, and the ratio of the constant impedance component to the constant power component in the load.

[0030] Select simultaneously each time and Each parameter is used, and the sensitivity analysis gradient method is employed. Calculate the sensitivity of the source-load parameter set changes to the power grid system damping ratio with the same gradient changes of 15% and +25%. The calculation results are shown in Table 3. (Selection) The largest source-load parameter set , recorded as This allows us to identify the source-charge parameter combination that is most sensitive to suppressing low-frequency oscillations.

[0031] In summary, the method and system for identifying source-load parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity provided by this invention, through the calculation of damping ratio sensitivity, identifies the new energy generating units, motor-type loads, and source-load parameter combinations that are most sensitive to the impact of power system oscillations. This provides a reference for improving the damping ratio and suppressing oscillations. The method of this invention can simultaneously identify parameter combinations of new energy generating units and motor-type loads, and can reflect the synergistic influence of both the source and load sides on the system damping ratio and oscillations. Compared with the identification of a single power source or load parameter, this method has guiding significance for locating and suppressing low-frequency oscillations in the system.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can still make modifications or equivalent substitutions to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention are within the protection scope of the pending claims.

[0033] Table 1 Active power and terminal voltage sensitivity of doubly-fed wind turbine units based on damping ratio Table 2 Active power and load structure sensitivity of motor-type loads based on damping ratio Table 3 Sensitivity based on source-load parameter combination according to damping ratio

Claims

1. A method for identifying source-charge parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity, characterized in that, include: Establish a power system simulation model containing multiple new energy generating units and multiple motor-type loads, and calculate the initial damping ratio of the system; Based on the initial damping ratio of the system, the average damping ratio sensitivity of each new energy unit is calculated, and the new energy unit with the largest average damping ratio sensitivity is selected. Based on the initial damping ratio of the system, the average damping ratio sensitivity of each type of motor load is calculated, and the type of motor load with the highest average damping ratio sensitivity is selected. A source-load parameter set is constructed using the new energy generating unit with the highest average damping ratio sensitivity and the motor load with the highest average damping ratio sensitivity. Source-load parameter sensitivity calculations are performed to identify the source-load parameter combination that is most sensitive to suppressing low-frequency oscillations.

2. The method for identifying source-charge parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity according to claim 1, characterized in that, The establishment of a power system simulation model containing multiple new energy generating units and multiple motor-type loads, and the calculation of the initial damping ratio of the system, includes: Establish a power system simulation model containing multiple new energy generating units and multiple motor-type loads; Set the component parameters for new energy generator units and motor-type loads as baseline parameters; Based on the baseline parameters, the initial damping ratio of the power system is calculated using the small-disturbance stability analysis method. The calculation method is as follows: ， In the formula, It is the real part of the eigenvalues ​​of the system state matrix under the reference parameters; It is the imaginary part of the eigenvalues ​​of the system state matrix under the reference parameters.

3. The method for identifying source-charge parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity according to claim 2, characterized in that, The step of calculating the average damping ratio sensitivity of each new energy unit based on the initial damping ratio of the system, and selecting the new energy unit with the highest average damping ratio sensitivity, includes: Calculate the active power-damping ratio sensitivity by changing the active power of each new energy unit separately. : ， In the formula, To standardize the active power regulation step size for new energy generating units, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the active power parameter of the renewable energy unit. The initial damping ratio of the power system; The active power of the new energy units in the benchmark parameters; Calculate the voltage-damping ratio sensitivity by changing the terminal voltage of each new energy unit separately. : ， In the formula, To ensure a uniform voltage regulation step size, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the terminal voltage parameter of the new energy unit. The initial damping ratio of the power system. It refers to the terminal voltage of the new energy unit in the benchmark parameters; Calculate the average damping ratio sensitivity of each new energy unit. : ， Select the new energy unit with the largest value, denoted as . .

4. The method for identifying source-charge parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity according to claim 3, characterized in that, The step of calculating the average damping ratio sensitivity of each type of motor load based on the initial damping ratio of the system, and selecting the type of motor load with the highest average damping ratio sensitivity, includes: Calculate the active power-damping ratio sensitivity by changing the active power of each type of motor load separately. : ， In the formula, To achieve a unified active power regulation step size, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the active power parameter of the load. The initial damping ratio of the power system; It is the active power of the load in the baseline parameters; Calculate the load structure-damping ratio sensitivity by changing the load structure for each type of motor load. : ， In the formula, To ensure a uniform load structure adjustment step size, The damping ratio is calculated using small-disturbance stability analysis after adjusting only the load structure parameter. The initial damping ratio of the power system. It is the load structure in the reference parameters; Calculate the average damping ratio sensitivity for each type of motor load. : ， Select the motor type load with the largest value, and denote it as... .

5. The method for identifying source-charge parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity according to claim 4, characterized in that, The source-load parameter set is constructed by the new energy unit with the highest average damping ratio sensitivity and the motor load with the highest average damping ratio sensitivity. Source-load parameter sensitivity calculations are then performed to identify the source-load parameter combination most sensitive to suppressing low-frequency oscillations, including: statistics and Adjustable parameters form a parameter set. and ,in These are the motor inertia time constant, damping coefficient, and voltage outer loop proportional-integral gain of the new energy generator unit. It is the per-unit value of the bus voltage of the load, and the ratio of the constant impedance component to the constant power component in the load; Select simultaneously each time and Using one parameter from each source-load group, the sensitivity of the source-load parameter set to the power grid system damping ratio is calculated using the sensitivity analysis gradient method. ; choose The source-load parameter set with the largest numerical value is denoted as This allows us to identify the source-charge parameter combination that is most sensitive to suppressing low-frequency oscillations.

6. The method for identifying source-charge parameter combinations for suppressing low-frequency oscillations based on damping ratio sensitivity according to claim 5, characterized in that, The simultaneous selection each time and Using one parameter from each source-load group, the sensitivity of the source-load parameter set to the power grid system damping ratio is calculated using the sensitivity analysis gradient method. ,include: The calculation method is as follows: ， In the formula, For the combined parameters, the first r Adjustment step size under each gradient, The combined parameters are in the first... r Damping ratio at each gradient t This refers to the total number of gradients.

7. A source-load parameter combination identification system for suppressing low-frequency oscillations based on damping ratio sensitivity, using the source-load parameter combination identification method for suppressing low-frequency oscillations based on damping ratio sensitivity according to any one of claims 1 to 6, characterized in that, include: The simulation model building unit establishes a power system simulation model containing multiple new energy generating units and multiple motor-type loads, and calculates the initial damping ratio of the system. The new energy unit selection unit calculates the average damping ratio sensitivity of each new energy unit based on the initial damping ratio of the system, and selects the new energy unit with the highest average damping ratio sensitivity. The motor load selection unit calculates the average damping ratio sensitivity of each motor load based on the initial damping ratio of the system, and selects the motor load with the highest average damping ratio sensitivity. The source-load parameter combination identification unit constructs a source-load parameter set by constructing the new energy unit with the highest average damping ratio sensitivity and the motor load with the highest average damping ratio sensitivity, performs source-load parameter sensitivity calculation, and identifies the source-load parameter combination that is most sensitive to suppressing low-frequency oscillations.

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