A Fast Tuning Method for Damping Controller Parameters of a Hybrid Energy Storage System

Abstract

A method for quickly tuning the parameters of a damping controller for a hybrid energy storage system discloses a method for quickly tuning the parameters of a stability controller for an energy storage system with a supercapacitor configured on the excitation side of compressed air. Taking the additional dual damping control channels (reactive power damping control channel, active power damping control channel) of the energy storage system with a supercapacitor configured on the excitation side of compressed air as the research object, based on mathematical model analysis, and based on the parameters of a power system stabilizer (PSS) with mature theory and wide engineering applications, a design method for quickly tuning the parameters of the reactive power damping controller and the active power damping controller is given. The method proposed in the present invention does not rely on the precise linearization of the mathematical model and has certain guiding significance for the tuning of controller parameters in actual engineering.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric energy storage, and more specifically, relates to a method for quickly tuning the parameters of a damping controller for a hybrid energy storage system. Background Art

[0002] In recent years, "two substitutions" mainly including clean substitution and electric energy substitution are important directions for the future development of the world's energy. On the one hand, new energy sources such as photovoltaic and wind power have inherent characteristics such as intermittency and volatility, and the problem of new energy consumption is prominent. Energy storage is an effective means to solve the imbalance of power supply and demand in time and space and realize the spatio-temporal transfer of energy. On the other hand, large-scale renewable energy is connected to the power system through power electronic devices, which changes the grid structure, affects the electromechanical oscillation mode of the power system, and also weakens the system damping and reduces the system stability.

[0003] In the field of energy storage systems, hybrid energy storage systems have attracted attention due to their characteristics of both power-type and energy-type energy storage systems. The compressed air energy storage system adopts a flexible excitation system based on fully controlled devices. Through the voltage stabilizing capacitor of the excitation system, it is connected in parallel with the super capacitor through a bidirectional chopper device. The formed compressed air and super capacitor hybrid system has the characteristics of both energy-type and power-type energy storage devices. While achieving more efficient suppression of new energy fluctuations, it also has the potential ability to provide various auxiliary services for the power system. Among them, it can provide three damping control channels through the control of the excitation voltage, the reactive power injected into the machine terminal, and the active power injected into the machine terminal, effectively improving the stability of the power system.

[0004] At present, for flexible excitation systems with excitation voltage control channels and reactive power control channels, existing literature has proposed methods such as linear optimal control, phase compensation method, and nonlinear control theory to design controller parameters and achieved good results. There are also many theoretical studies on the use of energy storage systems to improve the stability of power systems. However, most of the current research is based on complex model analysis and theoretical calculations, with problems such as difficult engineering application and complex parameter design. Therefore, it is necessary to propose a fast controller parameter tuning method based on theoretical analysis. Summary of the Invention

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0006] A method for quickly tuning the parameters of a damping controller for a hybrid energy storage system, including:

[0007] The hybrid energy storage system is a hybrid energy storage system with a super capacitor configured on the excitation side of a compressed air energy storage system;

[0008] The compressed air energy storage system adopts a synchronous generator, and the excitation system of the synchronous generator adopts an excitation system based on high-power fully controlled power electronic devices. The super capacitor is connected in parallel with the voltage stabilizing capacitor of the flexible excitation system through a bidirectional chopper device;

[0009] In the flexible excitation system, the high-voltage side of the excitation transformer is connected to the generator terminal. The excitation transformer is sequentially connected to the generator excitation winding through an AC LC filter, a fully controlled rectifier device, a voltage stabilizing capacitor, and a fully controlled chopper device;

[0010] The excitation system controls the active power P C and reactive power Q C exchanged between the excitation side of the energy storage system and the generator terminal. The active damping control channel and the reactive damping control channel, together with the conventional excitation side damping channel, constitute a three-damping control channel;

[0011] The reactive damping control channel is the second damping channel, which is controlled by a reactive damping controller. While adjusting the reactive power injected by the excitation system into the generator terminal, it provides damping for the power system. The active damping control channel is the third damping channel, which is controlled by an active damping controller. While adjusting the active power injected by the super capacitor into the generator terminal, it provides damping for the power system;

[0012] The excitation control channel of the synchronous generator is the first damping channel, which is controlled by a voltage regulator AVR and a power system stabilizer PSS. While adjusting the excitation voltage, it provides damping for the power system.

[0013] Preferably, the parameter setting method of the reactive damping controller adopts the following steps:

[0014] 1) Obtain the time constant of the PSS lead-lag link through engineering tuning or theoretical calculation methods;

[0015] The engineering tuning method is the PSS parameter tuning method. For an already operating system, the PSS parameters are obtained through on-site measurement;

[0016] The method for calculating the time constant of the PSS lead-lag link based on theory is as follows:

[0017] The electromagnetic torque provided by the PSS is:

[0018]

[0019] where, K 2 , K 3 , K 6 The expressions are as follows:

[0020]

[0021] In the formula, K A is the amplification factor of the voltage regulator, xTL is the sum of the main transformer reactance and the line reactance, x q is the quadrature-axis synchronous reactance, x'd is the direct-axis transient reactance, x d is the generator d-axis synchronous reactance, U t0 is the initial value of the generator terminal voltage, u tq0 is the initial value of the q-axis component of the generator terminal voltage, i tq0 is the initial value of the q-axis component of the generator terminal current, x q∑ , x d∑ , x′ d∑ are respectively x q , x d , x′ d and x TL sum;

[0022] The PSS equivalent transfer function is:

[0023]

[0024] The time constants T 2 , T 4 , T 10 are artificial empirical parameters, and the objective function for calculating T 1 , T 3 , T 5 is:

[0025]

[0026] In the formula, f n is the frequency to be analyzed, and N is the number of frequency points for analysis;

[0027] The constraint conditions of Equation (1) are:

[0028]

[0029] In the formula, f n.min and f n.max are 0.1 Hz and 2.5 Hz respectively, and are -30° and 20° respectively. T min and T max are 0.01 s and 5 s respectively;

[0030] 2) The reactive power damping controller uses a negative gain. Set the initial value of the reactive power damping controller time constant to be equal to the PSS time constant, and adjust the proportional coefficient according to the set method of the reactive power damping controller proportional coefficient until the critical gain is determined so that the system exhibits equal-amplitude oscillation. The proportional coefficient of the reactive power damping controller is selected to be 1 / 3 - 1 / 5 of the critical gain;

[0031] The method for adjusting the proportional coefficient of the set reactive power damping controller is as follows:

[0032] ① Select the initial value M of the proportional coefficient adjustment Q0 and the value interval m Q . When at the n Q -th proportional coefficient value, that is, M Q0 +m Q *(n Q -1), the system oscillation converges, and at the n Q +1-th proportional coefficient value, that is, M Q0 +m Q *n Q , when the system oscillation diverges, determine the value range (a Q , b Q ) of the critical gain, which is (M Q0 +m Q *(n Q -1), M Q0 +m Q *n Q );

[0033] ② Select the proportional coefficient (a Q +b Q ) / 2. If the system oscillation diverges at this coefficient, then assign (a Q +b Q ) / 2 to b Q . If the oscillation converges, then assign (a Q +b Q ) / 2 to a Q . If the system shows equal-amplitude oscillation, then (a Q +b Q ) / 2 is the critical gain.

[0034] ③ Repeat step ② until the system shows equal-amplitude oscillation to determine the critical gain of the controller;

[0035] 3) By observing the system oscillation frequency and damping during the small disturbance test, adjust the controller time constant. Based on the principle of keeping the dynamic gain unchanged, synchronously adjust the controller proportional coefficient; when the controller provides positive damping and the system oscillation frequency deviation does not exceed 2%, determine the reactive power damping controller time constant and proportional coefficient;

[0036] Preferably, the method for setting the parameters of the active damping controller is as follows:

[0037] 1) The active damping controller adopts negative proportional control. Adjust the proportional coefficient according to the set method for adjusting the proportional coefficient of the active damping controller until the critical gain is determined such that the system oscillation becomes deformed. The proportional coefficient of the active damping controller is selected as 1 / 3 to 1 / 5 of the critical gain;

[0038] The adjustment method for the set proportional coefficient of the active damping controller is as follows:

[0039] ① Select the initial value M of the proportional coefficient P0 and the value interval m P , when at the nth P proportional coefficient value, that is, M P0 +m P *(n P -1), the system oscillation converges, while at the (n P +1)th proportional coefficient value, that is, M P0 +m P *n P , the system oscillation diverges, determine the value range (a P , b P ) of the critical gain, which is (M P0 +m P *(n P -1), M P0 +m P *n P );

[0040] ② Select the proportional coefficient (a P +b P ) / 2. If the system oscillation diverges with this coefficient, then assign (a P +b P ) / 2 to b P . If the oscillation converges, then assign (a P +b P ) / 2 to a P . If the system oscillation becomes distorted, then (a P +b P ) / 2 is the critical gain;

[0041] ③ Repeat step ② until the system oscillation becomes distorted to determine the critical gain of the controller;

[0042] 2) By observing the system oscillation frequency and damping during the small disturbance test, adjust the controller time constant, and synchronously adjust the controller proportional coefficient on the principle of keeping the dynamic gain unchanged;

[0043] 3) When the controller provides positive damping and the system oscillation frequency deviation does not exceed 2%, determine the time constant and proportional coefficient of the active damping controller;

[0044] When the hybrid system needs to simultaneously activate the reactive damping controller and the active damping controller due to operation requirements, the reactive damping controller or the active damping controller can be preferentially selected for tuning, and the parameters of the two controllers are designed in sequence according to the above steps.

[0045] Preferably, the adjustment method for the controller time constant is as follows:

[0046] 1) When the system damping increases, the oscillation frequency increases, and the oscillation period decreases, increase the time constant of the lead link of the reactive power damping controller and the active power damping controller;

[0047] 2) When the system damping increases, the oscillation frequency decreases, and the oscillation period increases, decrease the time constant of the lead link of the reactive power damping controller and the active power damping controller, or increase the time constant of the lag link of the reactive power damping controller and the active power damping controller;

[0048] 3) When the system damping decreases, invert the controller, which is achieved by switching the positive and negative of the controller proportional coefficient.

[0049] The beneficial effects of the present invention are as follows: 1) A damping controller parameter tuning method for an additional double damping channel of an energy storage system with a supercapacitor configured on the excitation side of compressed air is provided.

[0050] 2) Based on the parameters of the power system stabilizer (PSS) with a mature theory and wide engineering applications, the proposed method is applicable to engineering applications and does not rely on an accurate mathematical model.

[0051] 3) The proposed method fully exploits the ability of the hybrid energy storage system to provide auxiliary services for the power system. Description of the Drawings

[0052] Figure 1 It is a structural diagram of an energy storage system with a supercapacitor configured on the excitation side of compressed air.

[0053] In the figure: 1. Flexible excitation system power unit, 2. Synchronous generator; 10. AC LC filter, 11. Rectifier, 12. Voltage stabilizing capacitor, 13. Chopper; 20. Excitation voltage, 21. Reactive power injected into the generator terminal by the hybrid system through the AC side, 22. Active power injected into the generator terminal by the hybrid system through the AC side, 23. Mechanical power of the compressed air energy storage system; 3. Supercapacitor energy storage system, 31. Supercapacitor, 32. Bidirectional chopper.

[0054] Figure 2 It is a structural diagram of a power system stabilizer, a reactive power damping controller, and an active power damping controller.

[0055] Figure 3 It is a comparison diagram of the time constant adjustment of the reactive power damping controller in a specific embodiment.

[0056] Figure 4 It is a comparison diagram of the time constant adjustment of the active power damping controller in a specific embodiment. Detailed Embodiments

[0057] The following further describes the present invention with reference to the drawings and embodiments.

[0058] Embodiment 1

[0059] A new energy storage system with a supercapacitor configured on the excitation side of a compressed air energy storage system in this embodiment is as Figure 1 shown.

[0060] The hybrid energy storage system is a hybrid energy storage system with a supercapacitor configured on the excitation side of a compressed air energy storage system;

[0061] The compressed air energy storage system uses a synchronous generator, and the excitation system of the synchronous generator uses an excitation system based on high-power fully-controlled power electronic devices. The supercapacitor is connected in parallel with the voltage stabilizing capacitor of the flexible excitation system through a bidirectional chopper device;

[0062] In the flexible excitation system, the high-voltage side of the excitation transformer is connected to the generator terminal. The excitation transformer is sequentially connected to the generator excitation winding through an AC LC filter, a fully-controlled rectifier device, a voltage stabilizing capacitor, and a fully-controlled chopper device;

[0063] The excitation system controls the active power P C exchanged between the excitation side of the energy storage system and the generator terminal, and the reactive power Q C , and the active damping control channel, the reactive damping control channel, and the conventional excitation side damping channel form a three-damping control channel;

[0064] The reactive damping control channel is the second damping channel, which is controlled by a reactive damping controller to provide damping for the power system while adjusting the reactive power injected by the excitation system into the generator terminal. The active damping control channel is the third damping channel, which is controlled by an active damping controller to provide damping for the power system while adjusting the active power injected by the supercapacitor into the generator terminal;

[0065] The synchronous generator excitation control channel is the first damping channel, which is controlled by a voltage regulator AVR and a power system stabilizer PSS to provide damping for the power system while adjusting the excitation voltage.

[0066] In this system, the generator of the compressed air energy storage system uses a synchronous generator 2, and the excitation system uses a flexible excitation system based on high-power fully-controlled power electronic devices. The core of this system is the flexible excitation system power unit 1, which mainly includes: an AC LC filter 10, a rectifier 11, a voltage stabilizing capacitor 12, and a chopper 13. The supercapacitor 31 in the supercapacitor energy storage system 3 is connected in parallel with the voltage stabilizing capacitor 12 of the flexible excitation system power unit 1 through a bidirectional chopper 30. This energy storage system can realize the functions of an energy-type and power-type energy storage system, improve the new energy consumption capacity, and at the same time, can also provide stronger auxiliary control capabilities for the power system.

[0067] The connection mode of the flexible excitation system is as follows: the generator terminal is connected to the high-voltage side of the excitation transformer, and the excitation transformer is sequentially connected to the generator excitation winding through the AC LC filter 10, rectifier 11, voltage stabilizing capacitor 12, and chopper 13.

[0068] The supercapacitor 31 is connected in parallel with the voltage stabilizing capacitor of the flexible excitation system through the bidirectional chopper 30, realizing the hybrid operation of the supercapacitor and the compressed air energy storage system, and the control function is realized through the converter.

[0069] The rectifier 11 aims to control the active power P C and reactive power Q C exchanged between the excitation side of the energy storage system and the generator terminal. P C and Q C respectively follow the command values P SCref and Q SCref , and P SCref and Q SCref are respectively controlled and output by the active damping controller and the reactive damping controller.

[0070] The chopper 13 is used to control the excitation voltage E fd to follow the command value E fdref , realizing the excitation control function. Among them, the excitation voltage reference value can be obtained by the voltage regulator + power system stabilizer.

[0071] The main parameters of the power system stabilizer are the proportional coefficient K S1 , the lead link time constants T 1 , T 3 , T 5 , and the lag link time constants T 2 , T 4 , T 10 .

[0072] The main parameters of the reactive damping controller are the proportional coefficient K QS1 , the lead link time constants T Q1 , T Q3 , T Q5 , and the lag link time constants T Q2 , T Q4 , T Q6 .

[0073] The main parameters of the active damping controller are the proportional coefficient K P , the lead link time constants T P1 , T P3 , T P5 , and the lag link time constants T P2 , T P4 , T P6 .

[0074] ForFigure 1 For the system shown, set the parameters of the reactive power damping controller and the active power damping controller. Among them, the method for setting the parameters of the reactive power damping controller adopts the following steps:

[0075] 1) Obtain the time constant of the PSS lead-lag link through engineering tuning or theoretical calculation methods;

[0076] The engineering tuning method is the PSS parameter tuning method. For an already-operating system, the PSS parameters have been obtained through on-site measurement;

[0077] The method for calculating the time constant of the PSS lead-lag link based on theory is as follows:

[0078] The electromagnetic torque provided by the PSS is:

[0079]

[0080] Among them, K 2 , K 3 , K 6 The expressions are as follows:

[0081]

[0082] In the formula, K A is the voltage regulator amplification factor, x TL is the sum of the main transformer reactance and the line reactance, x q is the quadrature-axis synchronous reactance, x'd is the direct-axis transient reactance, x d is the generator d-axis synchronous reactance, U t0 is the initial value of the generator terminal voltage, u tq0 is the initial value of the q-axis component of the generator terminal voltage, i tq0 is the initial value of the q-axis component of the generator terminal current, x q∑ , x d∑ , x′ d∑ are respectively the sums of x q , x d , x′ d and x TL ;

[0083] The equivalent transfer function of the PSS is:

[0084]

[0085] The time constants T 2 , T 4 , T 10 are selected as fixed values. The time constants T 2 , T 4 , T 10 are all artificial experience parameters. Calculate T 1, T 3 , T 5 The objective function of is:

[0086]

[0087] In the formula, f n is the frequency to be analyzed, and N is the number of frequency points for analysis;

[0088] The constraint conditions of Equation (6) are:

[0089]

[0090] In the formula, f n.min and f n.max are 0.1 Hz and 2.5 Hz respectively, and are -30° and 20° respectively. T min and T max are 0.01 s and 5 s respectively;

[0091] The research object of this embodiment is an actually operated generator set, and its PSS parameters are known, as shown in the following table:

[0092] Table 1 PSS controller parameters

[0093]

[0094]

[0095] 2) The reactive power damping controller adopts a negative gain. Set the initial value of the time constant of the reactive power damping controller to be equal to the PSS time constant, and adjust the proportional coefficient according to the set method of the proportional coefficient of the reactive power damping controller until the critical gain is determined so that the system exhibits equal-amplitude oscillation. The initial value of the proportional coefficient of the reactive power damping controller is selected to be 1 / 3 to 1 / 5 of the critical gain;

[0096] Specifically,

[0097] The initial value of the time constant of the reactive power damping controller is set to T Q1 , T Q3 is 0.17 s; T Q2 , T Q4 is 0.03 s, T Q5 , T Q6 is 0.03 s.

[0098] The set method for adjusting the proportional coefficient of the reactive power damping controller is:

[0099] ① Select the initial value M Q0 of the proportional coefficient adjustment and the value interval m Q , when at the nth Qa proportional coefficient value, i.e., M Q0 +m Q *(n Q -1), the system oscillation converges. While at the (n Q +1)th proportional coefficient value, i.e., M Q0 +m Q *n Q when the system oscillation diverges, determine the value range of the critical gain (a Q , b Q ) which is (M Q0 +m Q *(n Q -1), M Q0 +m Q *n Q );

[0100] ② Select the proportional coefficient (a Q +b Q ) / 2. If the system oscillation diverges at this coefficient, assign (a Q +b Q ) / 2 to b Q . If the oscillation converges, assign (a Q +b Q ) / 2 to a Q . If the system shows sustained oscillation, (a Q +b Q ) / 2 is the critical gain.

[0101] ③ Repeat step ② until the system shows sustained oscillation to determine the critical gain of the controller.

[0102] Select the initial value of the proportional coefficient M Q0 as -10, and the value interval m Q as 10. According to the above steps, when the proportional coefficient is -165, the system shows sustained oscillation. Therefore, when T Q1 , T Q3 is 0.17 s; when T Q2 , T Q4 is 0.03 s; when T Q5 , T Q6 is 0.03 s, the critical gain of the reactive power damping controller is -165, and select its initial value of the proportional coefficient K QS1 as -50.

[0103] 3) By observing the system oscillation frequency and damping during the small disturbance test, adjust the controller time constant to keep the dynamic gain unchanged as a principle, and synchronously adjust the controller proportional coefficient; when the controller provides positive damping and the system oscillation frequency deviation does not exceed 2%, determine the time constant and proportional coefficient of the reactive power damping controller.

[0104] Define the initial parameters of the reactive power damping controller RPDC1 as: K QS1 Set it to -50, and set the time constant of the lead-lag link to: T Q1 , T Q3 is 0.17 s; T Q2 , T Q4 is 0.03 s; T Q5 , T Q6 is 0.03 s. The simulation results under this parameter are as shown in Figure 3 . Under this control parameter, the oscillation frequency of the system is 1.72 Hz, and the damping ratio is 0.358. Compared with the oscillation frequency of 1.52 Hz and the damping ratio of 0.1476 without the damping controller, the offset rate of the oscillation frequency is 13.2%, and the damping ratio increases by 0.2104.

[0105] That is, under the initial parameters, the system damping increases, the oscillation frequency increases, and the oscillation period decreases. At this time, increase the time constant of the lead link of the reactive power damping controller.

[0106] Define the adjusted reactive power damping controller parameter RPDC2 as: K QS1 is -11.65, and set the time constant of the lead-lag link: T Q1 , T Q3 is 0.4 s; T Q2 , T Q4 is 0.03 s, T Q5 , T Q6 is 0.03 s. The simulation results are as shown in Figure 4 . Under this parameter, the oscillation frequency of the system is 1.49 Hz, and the damping ratio is 0.369. Compared with the oscillation frequency of 1.52 Hz and the damping ratio of 0.1476 without the damping controller, the offset rate of the oscillation frequency is 2%, and the damping ratio increases by 0.2214.

[0107] Based on the above analysis, determine the final parameters of the reactive power damping controller as: K QS1 Set it to -11.65, T Q1 , T Q3 is 0.4 s; T Q2 , T Q4 is 0.03 s, T Q5 , T Q6 is 0.03 s.

[0108] The method for tuning the parameters of the active power damping controller described above adopts the following steps:

[0109] 1) The active power damping controller adopts negative proportional control, adjusts the proportional coefficient according to the set method for adjusting the proportional coefficient of the active power damping controller until the critical gain is determined so that the system exhibits equal-amplitude oscillation, and the proportional selection of the active power damping controller is 1 / 3 to 1 / 5 of the critical gain;

[0110] The method for adjusting the proportional coefficient of the set active damping controller is as follows:

[0111] ① Select the initial value M of the proportional coefficient P0 and the value interval m P . When at the n P th proportional coefficient value, that is, M P0 +m P *(n P -1), the system oscillation converges, while at the n P +1th proportional coefficient value, that is, M P0 +m P *n P , the system oscillation diverges, determine the value range (a P , b P ) of the critical gain, which is (M P0 +m P *(n P -1), M P0 +m P *n P );

[0112] ② Select the proportional coefficient (a P +b P ) / 2. If the system oscillation diverges with this coefficient, assign (a P +b P ) / 2 to b P . If the oscillation converges, assign (a P +b P ) / 2 to a P . If the system oscillation is deformed, (a P +b P ) / 2 is the critical gain.

[0113] ③ Repeat step ② until the system oscillation is deformed to determine the critical gain of the controller.

[0114] Select the initial value M of the proportional coefficient P0 as -10, and the value interval m P as 10. According to the above tuning method, when the proportional coefficient is -235, the system waveform is deformed. Therefore, the critical gain of the active damping controller is -235, and the initial value of its proportional coefficient K P is -50.

[0115] Set the initial value of the active damping controller parameters, that is, use pure proportional control, and the value of K P is -50. The simulation results are as Figure 4As shown, under this parameter, the oscillation frequency of the system is 1.49 Hz and the damping ratio is 0.37. Compared with the oscillation frequency of 1.52 Hz and the damping ratio of 0.1476 without the damping controller, the offset rate of the oscillation frequency is 2%, and the damping ratio increases by 0.2224.

[0116] The final parameters of the active damping controller are: pure proportional control, and the proportional coefficient K P is -50. As can be seen from the figure, the active damping controller obtained by this parameter tuning method has a good control effect and can effectively improve the stability of the power system.

[0117] It should be understood that those of ordinary skill in the art can make improvements or transformations according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present invention.

Claims

1. A method for quickly tuning the parameters of a damping controller for a hybrid energy storage system, characterized in that, it includes: The hybrid energy storage system is a hybrid energy storage system with a supercapacitor configured on the excitation side of a compressed air energy storage system; The compressed air energy storage system uses a synchronous generator, and the excitation system of the synchronous generator uses an excitation system based on high-power fully controlled power electronic devices. The supercapacitor is connected in parallel with the voltage stabilizing capacitor of the flexible excitation system through a bidirectional chopper device; On the high-voltage side of the excitation transformer in the flexible excitation system, it is connected to the generator terminal. The excitation transformer is sequentially connected to the generator excitation winding through an AC LC filter, a fully controlled rectifier device, a voltage stabilizing capacitor, and a fully controlled chopper device; The excitation system controls the active power P exchanged between the excitation side of the energy storage system and the generator terminal C and the reactive power Q C , respectively adding an active damping control channel and a reactive damping control channel, which together with the conventional damping channel on the excitation side form a three-damping control channel; The reactive power damping control channel is the second damping channel, which is controlled by a reactive power damping controller. While adjusting the reactive power injected by the excitation system into the generator terminal, it provides damping for the power system; the active power damping control channel is the third damping channel, which is controlled by an active power damping controller. While adjusting the active power injected by the supercapacitor into the generator terminal, it provides damping for the power system; The excitation control channel of the synchronous generator is the first damping channel, which is controlled by a voltage regulator AVR and a power system stabilizer PSS. While adjusting the excitation voltage, it provides damping for the power system; The parameter tuning method of the reactive power damping controller adopts the following steps: 1) Obtain the time constant of the PSS lead-lag link through engineering tuning or theoretical calculation methods; The engineering tuning method is the PSS parameter tuning method. For an already operating system, the PSS parameters are obtained through on-site measurement; The method for calculating the time constant of the PSS lead-lag link based on theory is as follows: The electromagnetic torque provided by the PSS is: Among them, K 2 , K 3 , K 6 The expressions are as follows: where K A is the amplification factor of the voltage regulator, x TL is the sum of the reactance of the main transformer and the line reactance, x q is the quadrature-axis synchronous reactance, x'd is the direct-axis transient reactance, x d is the synchronous reactance of the generator d-axis, U t0 is the initial value of the generator terminal voltage, u tq0 is the initial value of the q-axis component of the generator terminal voltage, i tq0 is the initial value of the q-axis component of the generator terminal current, x q∑ , x d∑ , x′ d∑ are respectively the sum of x q , x d , x′ d and x TL ; The equivalent transfer function of the PSS is: Time constant T 2 , T 4 , T 10 are artificial empirical parameters, and the objective function for calculating T 1 , T 3 , T 5 is: where f n is the frequency to be analyzed and N is the number of frequency points for analysis; The constraint condition of Equation (4) is: where f n.min and f n.max are 0.1 Hz and 2.5 Hz respectively, and are -30° and 20° respectively, T min and T max are 0.01 s and 5 s respectively.

2. According to the method for quickly tuning the parameters of a damping controller for a hybrid energy storage system described in claim 1, characterized in that, The parameter tuning method of the reactive power damping controller further includes the following steps: 2) The reactive power damping controller uses a negative gain. Set the initial value of the time constant of the reactive power damping controller to be equal to the PSS time constant. Adjust the proportional coefficient according to the set method for adjusting the proportional coefficient of the reactive power damping controller until the critical gain is determined so that the system exhibits equal-amplitude oscillation. The proportional coefficient of the reactive power damping controller is selected to be 1 / 3 to 1 / 5 of the critical gain; The set method for adjusting the proportional coefficient of the reactive power damping controller is: ①Select the initial value M of the proportionality coefficient adjustment Q0 and the value interval m Q . When at the n Q th proportionality coefficient value, i.e., M Q0 +m Q *(n Q -1), the system oscillation converges, and at the n Q +1th proportionality coefficient value, i.e., M Q0 +m Q *n Q , when the system oscillation diverges, determine the value range (a Q , b Q ) of the critical gain, which is (M Q0 +m Q *(n Q -1), M Q0 +m Q *n Q ); ② Proportional coefficient selection (a Q + b Q ) / 2. If the system oscillates and diverges under this coefficient, then assign (a Q + b Q ) / 2 to b Q . If the oscillation converges, then assign (a Q + b Q ) / 2 to a Q . If the system exhibits sustained oscillation, then (a Q + b Q ) / 2 is the critical gain. ③ Repeat step ② until the system exhibits equal-amplitude oscillation and determine the critical gain of the controller; 3) By observing the system oscillation frequency and damping during a small disturbance test, adjust the controller time constant. Based on the principle of keeping the dynamic gain unchanged, synchronously adjust the controller proportional coefficient; when the controller provides positive damping and the system oscillation frequency deviation does not exceed 2%, determine the time constant and proportional coefficient of the reactive power damping controller.

3. According to the method for quickly tuning the parameters of a damping controller for a hybrid energy storage system described in claim 1, characterized in that, The parameter tuning method of the active power damping controller adopts the following steps: 1) The active damping controller adopts negative proportional control. Adjust the proportional coefficient according to the set adjustment method of the proportional coefficient of the active damping controller until the critical gain is determined and the system oscillation is distorted. The proportional of the active damping controller is selected as 1 / 3 to 1 / 5 of the critical gain; The set adjustment method of the proportional coefficient of the active damping controller is as follows: ① Select the initial value M of the proportionality coefficient P0 and the value interval m P . When at the n P -th proportionality coefficient value, that is, M P0 +m P *(n P -1), the system oscillation converges, and at the (n P +1)-th proportionality coefficient value, that is, M P0 +m P *n P ), when the system oscillation diverges, determine the value range (a P , b P ) which is (M P0 +m P *(n P -1), M P0 +m P *n P ); ② Selection of proportionality coefficient (a P + b P ) / 2. If the system oscillates and diverges under this coefficient, then assign (a P + b P ) / 2 to b P . If the oscillation converges, then assign (a P + b P ) / 2 to a P . If the system oscillation shows deformation, then (a P + b P ) / 2 is the critical gain; ③ Repeat step ② until the system oscillation is distorted and the critical gain of the controller is determined; 2) By observing the system oscillation frequency and damping during the small disturbance test, adjust the controller time constant, and synchronously adjust the controller proportional coefficient on the principle of keeping the dynamic gain unchanged; 3) When the controller provides positive damping and the system oscillation frequency deviation does not exceed 2%, determine the time constant and proportional coefficient of the active damping controller; When the hybrid system needs to simultaneously input the reactive damping controller and the active damping controller due to operation requirements, the reactive damping controller or the active damping controller can be preferentially selected for tuning, and the parameters of the two controllers are designed in sequence according to the above steps.

4. According to a method for quickly tuning the parameters of a damping controller of a hybrid energy storage system as described in claim 1, it is characterized in that: The adjustment method of the controller time constant is as follows: 1) When the system damping increases, the oscillation frequency increases, and the oscillation period decreases, increase the time constant of the lead link of the reactive damping controller and the active damping controller; 2) When the system damping increases, the oscillation frequency decreases, and the oscillation period increases, decrease the time constant of the lead link of the reactive damping controller and the active damping controller, or increase the time constant of the lag link of the reactive damping controller and the active damping controller; 3) When the system damping decreases, reverse the controller, which is achieved by converting the positive and negative of the controller proportional coefficient.

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