Distributed phase modifier additional excitation system control method considering PSO-GWO-PID algorithm

Abstract

The invention discloses a distributed phase modifier additional excitation system control method considering a PSO-GWO-PID algorithm, and the method comprises the following steps: carrying out the preprocessing of a PID parameter of a feed-forward link of a grid-connected bus voltage through the combination of a particle swarm algorithm, and obtaining an optimal PID controller parameter of the feed-forward link based on a gray wolf algorithm; obtaining first data of the phase modifier, evaluating the transient stability level of the phase modifier in combination with a Lyapunov function, and obtaining a terminal voltage additional given value; and introducing the optimal PID controller parameter of the feedforward link and the additional given value of the terminal voltage to an original excitation system of the conventional phase modifier to obtain an additional excitation system of the phase modifier. The problems that in the prior art, the transient stability of the distributed phase modifier is weak, and the adjustment effect of a conventional control strategy of an excitation system of the phase modifier on the bus voltage is not obvious are effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of distributed phase regulator supplementary excitation systems, and in particular to a distributed phase regulator supplementary excitation system control method taking into account a PSO-GWO-PID algorithm. Background Art

[0002] As the proportion of new energy grid-connected continues to rise, problems such as insufficient dynamic reactive power and low voltage levels in the power grid have become increasingly prominent. The new synchronous condenser (SC) has the characteristics of low energy consumption and fast response speed, and has become the main device for improving the voltage strength of the power grid. The deployment of distributed condensers in new energy stations can effectively improve the transmission capacity of new energy.

[0003] With the steady progress of my country's energy transformation, small-capacity thermal power units are gradually being eliminated due to their low energy utilization and serious pollution. At the same time, due to the large-scale grid connection of new energy power generation and the rapid development of high-voltage direct current transmission, the AC side of the power system has become increasingly weak, requiring the system's fault adjustment time to be shortened.

[0004] In this context, selecting retired thermal power units that meet the activation requirements and re-operating them in phase-shifting mode can provide dynamic reactive power support for the power grid while effectively utilizing obsolete resources, thereby improving system operation stability.

[0005] However, the coupling between the above-mentioned phase modulators and the new energy units in the event of a fault can easily cause transient power angle stability problems, making it impossible for the phase modulators to shorten the oscillation swing time of the rotor angle caused by the fault. At the same time, the conventional control strategy of the phase modulator excitation system has no obvious effect on the regulation of the bus voltage of its grid-connected system. Therefore, the relevant research on the control strategy of the phase modulator excitation system is still incomplete. Further research on the phase modulator excitation control strategy is of great significance to improving the voltage support capacity of the phase modulator.

[0006] In the prior art, there are problems such as weak transient stability of distributed phase regulators and insignificant regulation effect of conventional control strategies of the phase regulator's excitation system on the bus voltage. Summary of the invention

[0007] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a control method for an additional excitation system of a distributed phase modulator taking into account the PSO-GWO-PID algorithm, which improves the regulation effect of the phase modulator on the bus voltage of its grid-connected point in both transient and steady states by introducing a feedforward control strategy of the excitation system, and then superimposes the additional voltage control amount on the set value of the machine-end voltage to realize transient stability regulation of the phase modulator, effectively solving the problems in the prior art that the transient stability of the distributed phase modulator is weak and the conventional control strategy of the phase modulator's excitation system has no obvious regulation effect on the bus voltage.

[0008] To achieve the above object, the present invention provides the following technical solutions: A control method for a distributed phase condenser additional excitation system taking into account a PSO-GWO-PID algorithm comprises the following steps: preprocessing the PID parameters of a feedforward link of a grid-connected bus voltage in combination with a particle swarm algorithm, and obtaining the optimal PID controller parameters of the feedforward link based on a grey wolf algorithm; obtaining the first data of the phase condenser, and evaluating the transient stability level of the phase condenser in combination with a Lyapunov function to obtain an additional given value of the terminal voltage; and introducing the optimal PID controller parameters of the feedforward link and the additional given value of the terminal voltage into an original excitation system of a conventional phase condenser to obtain an additional excitation system of the phase condenser.

[0009] In a preferred embodiment, the PID parameters of the feedforward link of the grid-connected bus voltage are preprocessed in combination with the particle swarm algorithm, specifically: the population size of the initial particle swarm and the parameter range of the PID parameters of the feedforward link are defined; within the defined parameter range, a number of particles are randomly generated in combination with a preset inertia coefficient and a number of groups of learning factors to obtain an initial wolf pack; the fitness of each particle in the initial wolf pack is calculated to obtain the initial feedforward link PID controller parameters.

[0010] In a preferred embodiment, the optimal feedforward link PID controller parameters are obtained based on the gray wolf algorithm, specifically: real-time acquisition of the grid-connected bus voltage deviation value under each group of initial feedforward link PID controller parameters; feedback of the grid-connected bus voltage deviation value to the fitness function of the gray wolf algorithm to obtain several groups of wolf groups with optimal fitness values; calculation of the gray wolf positions and search directions of the wolf groups with optimal fitness values ​​of several groups of wolf groups with optimal fitness values; when the fitness function value of the gray wolf algorithm approaches zero or reaches the maximum number of iterations, the optimal feedforward link PID controller parameters are obtained.

[0011] In a preferred embodiment, the first data of the phase modulator is obtained, and the transient stability level of the phase modulator is evaluated in combination with the Lyapunov function to obtain the additional given value of the machine-end voltage, specifically: the first data of the phase modulator includes the phase modulator electromagnetic power and the phase modulator speed deviation; it is set that when the phase modulator terminal voltage is greater than the first preset threshold and the rate of change of the active power is greater than the second preset threshold, the direction of the phase modulator electromagnetic power flowing to the power grid is the positive direction; if the camera electromagnetic power is positive and the phase modulator speed deviation is positive, the machine-end voltage additional given value controls the output of the machine-end voltage additional given positive value; if the camera electromagnetic power is negative and the phase modulator speed deviation is negative, the machine-end voltage additional given value controls the output of the machine-end voltage additional given positive value. A positive value is set; if the camera electromagnetic power is negative and the phase shifter speed deviation is positive, the machine-end voltage additional given value controls the output of the machine-end voltage additional given negative value; if the camera electromagnetic power is positive and the phase shifter speed deviation is negative, the machine-end voltage additional given value controls the output of the machine-end voltage additional given negative value; the size of the machine-end voltage additional given positive value depends on the offset between the actual speed of the unit and the rated speed and the first set gain at this time, and the machine-end voltage additional given positive value is set not greater than the machine-end voltage additional given maximum value; the size of the machine-end voltage additional given negative value depends on the offset between the actual speed of the unit and the rated speed and the second set gain at this time, and the machine-end voltage additional given negative value is set not less than the machine-end voltage additional given minimum value.

[0012] In a preferred embodiment, the optimal feedforward link PID controller parameters and the machine-end voltage additional set value are introduced into the original excitation system of a conventional phase modulator to obtain a phase modulator additional excitation system, specifically: the phase modulator additional excitation system includes: conventional phase modulator excitation control, PSO-GWO-PID feedforward control, and machine-end voltage additional set value control; the feedforward control superposition of the grid-connected bus output by the PSO-GWO-PID feedforward control is obtained based on the phase modulator excitation system control strategy of the PSO-GWO-PID algorithm with the grid-connected point bus voltage error as the feedforward input; the machine-end voltage additional set value control outputs the machine-end voltage additional set value by means of adaptive gain, and the greater the phase modulator deviates from the rated speed, the greater the output machine-end voltage additional set value.

[0013] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: 1. By introducing the excitation system feedforward control strategy, the regulation effect of the phase modulator on the bus voltage at its grid connection point in both transient and steady states is improved, and then the additional voltage control amount is superimposed on the set value of the machine-end voltage to achieve transient stability regulation of the phase modulator, which effectively solves the problems in the prior art that the transient stability of the distributed phase modulator is weak and the conventional control strategy of the phase modulator's excitation system has no obvious regulation effect on the bus voltage.

[0014] 2. A distributed phase-shifting auxiliary excitation system control method taking into account the PSO-GWO-PID algorithm is adopted to combine the conventional grey wolf algorithm with the particle swarm algorithm. The particle swarm algorithm is used to pre-identify the parameters of the wolf pack, thereby obtaining the initial population of the wolf pack, so that the wolf pack can obtain a higher fitness in the initial stage and improve the accuracy of the algorithm.

[0015] 3. By introducing the feedforward control strategy based on the PSO-GWO-PID algorithm on the basis of the conventional control strategy of the phase-converter excitation system, the connection between the excitation system and the system voltage is strengthened, thereby achieving the dual regulation of phase-converter terminal voltage stability and grid-connected point bus voltage stability.

[0016] 4. By superimposing an additional given value of the machine-end voltage on the basis of the conventional control strategy of the phase-converter excitation system, the transient power angle stability is improved during the acceleration and deceleration of the phase-converter, thereby achieving the improvement of the transient stability of the distributed phase-converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A flow chart of a method for controlling a distributed phase-converter auxiliary excitation system taking into account a PSO-GWO-PID algorithm provided in an embodiment of the present application; Figure 2 A topological structure diagram of a phase regulator auxiliary excitation system of a distributed phase regulator auxiliary excitation system control method taking into account a PSO-GWO-PID algorithm provided in an embodiment of the present application; Figure 3 A topological structure diagram of a simulation system for a distributed phase-converter additional excitation system control method taking into account a PSO-GWO-PID algorithm provided in an embodiment of the present application; Figure 4 A comparison chart of simulation results of a calculation example of a distributed phase-converter additional excitation system control method taking into account the PSO-GWO-PID algorithm provided in an embodiment of the present application; Figure 5 A method diagram of a distributed phase regulator additional excitation system control method taking into account the PSO-GWO-PID algorithm provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "include..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0020] Embodiment 1, Figure 1 A control method for a distributed phase regulator additional excitation system taking into account a PSO-GWO-PID algorithm is provided, comprising the following steps: Step S1, preprocessing the PID parameters of the feedforward link of the grid-connected bus voltage in combination with the particle swarm algorithm, and obtaining the optimal feedforward link PID controller parameters based on the grey wolf algorithm.

[0021] S11, pre-identify the PID parameters of the feedforward link of the grid-connected bus voltage by combining the particle swarm algorithm to obtain an initial wolf pack; Particle swarm algorithm (PSO) is an optimization algorithm that searches for the optimal solution by simulating the foraging behavior of bird flocks. In order to measure the quality of PID controller parameters, the particle swarm algorithm requires an evaluation standard. This application uses the ITAE function as the fitness function in the particle swarm algorithm. The calculation formula of the ITAE function is defined as follows:

[0022] Where: t is time, is the deviation between the target voltage and the actual voltage.

[0023] It should be noted that the ITAE function is used to measure the weighted absolute value of the system error over time. A smaller ITAE value indicates better system performance, that is, the weighted sum of the system errors over time is minimized.

[0024] The fitness function in the particle swarm algorithm uses the ITAE function, and the initial feedforward link PID controller parameters are randomly generated in the initial wolf pack. ,in They represent the proportional parameter, integral parameter and differential parameter respectively.

[0025] Before identification, the particle swarm algorithm is used to determine the initial population. The parameters are pre-identified according to the input and output data of the distributed phase regulator to obtain a group of populations. The pre-identification results are used as the initial population. In this way, the wolf pack can obtain a higher fitness in the early stage, thereby greatly improving the accuracy of parameter identification.

[0026] The initial wolf group is obtained by the following steps: setting the particle swarm initialization parameters, including the population size N = 200, the variable range [0, 200], the inertia coefficient of 0.5 and the learning factor , complete the particle swarm initialization state, thereby obtaining a set of populations obtained by parameter pre-identification, and use the pre-identification results as the initialization population of the wolf pack.

[0027] S12, randomly generating initial feedforward link PID controller parameters in the initial wolf pack, assigning them to the excitation control system, and performing calculations of the grey wolf algorithm; The grid-connected bus voltage deviation value under each set of parameters is collected in real time, and the grid-connected bus voltage deviation value under each set of parameters is fed back to the fitness function of the grey wolf algorithm.

[0028] The fitness function of the Grey Wolf Algorithm also uses the ITAE function; The grid-connected bus voltage deviation value under each set of parameters is fed back to the fitness function of the Grey Wolf Algorithm, as shown in formula (1): (1) Where: t represents time, Indicates the deviation between the given voltage value of the grid-connected bus and the actual voltage of the bus.

[0029] S13, when the fitness function value of the gray wolf algorithm approaches zero or reaches the maximum number of iterations, the optimal feedforward link PID controller parameters are obtained, otherwise the current position of the gray wolf and the next predation direction are refreshed, and the gray wolf algorithm is performed again; S13-1, if the fitness function value of the gray wolf algorithm approaches zero or reaches the maximum number of iterations, the corresponding feedforward link PID controller parameters are output; S13-2, if the fitness function value of the gray wolf algorithm does not tend to zero or does not reach the maximum number of iterations, the current position of the gray wolf and the next hunting direction are refreshed, and the wolf pack with the best fitness value is recalculated.

[0030] The current position of the gray wolf and the direction of its next predation are as follows: (2) Where: represent The direction of movement of the wolf pack, represent The direction of movement of the wolf pack, represent The direction of the wolf pack's movement, Indicates updating the position of the gray wolf.

[0031] in The layer wolf pack is responsible for leading the entire wolf pack to hunt prey, which is the optimal solution in the optimization algorithm; The wolf pack is responsible for assisting Wolfpack, which is a suboptimal solution in the optimization algorithm; The wolf pack obeys and Command and decision-making, responsible for reconnaissance, sentry, etc. and will be reduced to ; The wolf pack on the first layer follows the three wolf packs above.

[0032] During the entire search process, due to the uncertainty of the optimal solution (prey location), it is assumed that Wolf, Wolf and Wolves are closer to their prey, according to Wolf, Wolf and The position of the wolf is used to determine the position of the prey, and the position information of other wolves is updated at the same time, and repeated iterations gradually approach the prey.

[0033] It should be noted that Wolves, Wolves and Wolves, among them , and Representing three layers of wolf packs, The layer wolf pack is responsible for leading the entire wolf pack to hunt prey, which is the optimal solution in the optimization algorithm; The wolf pack is responsible for assisting Wolfpack, which is a suboptimal solution in the optimization algorithm; The wolf pack obeys and The orders and decisions of the police are to be carried out, and they are responsible for reconnaissance and sentry duty; Wolves and The wolf pack will be reduced to Wolf pack; the remaining wolves follow the three wolf packs above.

[0034] The feedforward control strategy of the phase-converter excitation system based on the PSO-GWO-PID algorithm takes the grid-connected bus voltage error as the feedforward input and calculates the feedforward control superposition. When the system operates normally, the feedforward link will not affect other links of the excitation system.

[0035] When the grid-connected bus voltage fluctuates, the PSO-GWO algorithm is used to perform online optimization of its PID parameters, and the corresponding PID parameters are selected according to the fitness level, forming a grid-connected bus feedforward voltage closed-loop regulation, which increases the monitoring function of the grid-connected bus voltage of the phase-shifting machine. It does not affect the steady-state regulation characteristics of the current excitation system control, and at the same time strengthens the connection between the excitation system and the system voltage in the transient process, realizing the dual regulation of the phase-shifting machine terminal voltage stability and the grid-connected point bus voltage stability. Relying on the superiority of the PSO-GWO algorithm in parameter optimization, this control strategy can better adapt to the requirements of strong voltage regulation capability and high precision of modern power grids.

[0036] Step S2, obtaining the first data of the phase regulator, evaluating the transient stability level of the phase regulator in combination with the Lyapunov function, and obtaining the additional given value of the terminal voltage; the first data of the phase regulator includes the electromagnetic power of the phase regulator and the speed deviation of the phase regulator.

[0037] Before the fault occurs, the additional control is not started and the system is in the normal excitation control state. At this time, the additional set value of the machine-end voltage is set to zero; when a transient fault occurs in the system (such as a grid short circuit or other disturbances), the excitation system of the phase regulator will start the additional set value control of the machine-end voltage.

[0038] The dynamic behaviors of power and speed of distributed phase regulators in new energy stations are complex under transient faults. From the perspective of phase regulator energy conservation, a Lyapunov function can be established to evaluate the transient stability level of the phase regulator. The transient stability of the phase regulator can be analyzed by the Lyapunov function, and the additional control quantity can be adjusted according to the electromagnetic power and speed deviation of the phase regulator to restore the phase regulator to a synchronous state.

[0039] S21, ignoring the mechanical damping of the condenser, its inherent synchronous torque and damping torque, the dynamic process description of the Lyapunov function to evaluate the transient stability level of the condenser is established as shown in formula (3): (3) Where: For the transient stability level of the phase regulator, represents the steady-state synchronous angular velocity, Indicates the phase shifter speed deviation, Represents the electromagnetic power of the phase regulator.

[0040] From formula (3), it can be obtained that the transient stability level of the phase-converter is related to the phase-converter speed deviation and electromagnetic power, which is specifically shown as follows: S22, if the transient stability level of the camera tends to be negative, the additional control of the excitation system makes the transient stability level of the camera decrease positively (slow down the energy accumulation speed) or increase negatively (accumulate energy speed faster), so as to make the phase regulator resume synchronous operation.

[0041] In order to improve the transient stability of the phase condenser, the change requirements of the electromagnetic power of the phase condenser are shown in Table 1:

[0042] Table 1 Phase condenser power change requirements considering quadrant fluctuations S23, analyzing Table 1, we get the following conclusions: If the phase condenser speed deviation is positive and the phase condenser electromagnetic power is positive, the absolute value of the phase condenser electromagnetic power increases; If the phase condenser speed deviation is positive and the phase condenser electromagnetic power is negative, the absolute value of the phase condenser electromagnetic power decreases; If the phase condenser speed deviation is negative and the phase condenser electromagnetic power is positive, the absolute value of the phase condenser electromagnetic power decreases; If the speed deviation of the phase condenser is negative and the electromagnetic power of the phase condenser is negative, the absolute value of the electromagnetic power of the phase condenser increases.

[0043] It is set that when the phase modulator terminal voltage is greater than a first preset threshold value and the rate of change of active power is greater than a second preset threshold value, the direction in which the phase modulator electromagnetic power flows to the power grid is a positive direction; If the camera electromagnetic power is positive and the phase shifter speed deviation is positive, the machine terminal voltage additional given value controls the output machine terminal voltage additional given positive value; If the camera electromagnetic power is negative and the phase shifter speed deviation is negative, the machine terminal voltage additional given value controls the output machine terminal voltage additional given positive value; If the camera electromagnetic power is negative and the phase shifter speed deviation is positive, the machine terminal voltage additional given value controls the output machine terminal voltage additional given negative value; If the camera electromagnetic power is positive and the phase regulator speed deviation is negative, the machine terminal voltage additional given value controls the output machine terminal voltage additional given negative value.

[0044] It should be noted that the first preset threshold is defined as 0.2, and the second preset threshold is defined as 30. It should be noted that the size of the additional given positive value of the machine-end voltage depends on the offset between the actual speed and the rated speed of the unit at this time and the first set gain, and the additional given positive value of the machine-end voltage is set not to be greater than the additional given maximum value of the machine-end voltage; the size of the additional given negative value of the machine-end voltage depends on the offset between the actual speed and the rated speed of the unit at this time and the second set gain, and the additional given negative value of the machine-end voltage is set not to be less than the additional given minimum value of the machine-end voltage.

[0045] Step S3, introducing the optimal feedforward link PID controller parameters and the additional set value of the terminal voltage into the original excitation system of the conventional phase modulator to obtain the additional excitation system of the phase modulator.

[0046] On the basis of the original excitation system of the conventional phase-converter, an additional grid-connected bus voltage feedforward link and an additional set value of the superimposed terminal voltage are introduced to adjust the system voltage and stabilize the phase-converter power angle, thus obtaining the phase-converter additional excitation system.

[0047] The topology of the additional excitation system of the phase regulator is as follows: Figure 2 As shown, it specifically includes: the middle control module is the conventional excitation control of the phase regulator, the upper control module is the PSO-GWO-PID feedforward control, and the lower control module is the additional set value control of the terminal voltage; The feedforward control superposition of the grid-connected bus output by the PSO-GWO-PID feedforward control is obtained by taking the grid-connected bus voltage error as the feedforward input based on the phase-converter excitation system control strategy of the PSO-GWO-PID algorithm; The machine-end voltage additional set value control uses an adaptive gain method to output the machine-end voltage additional set value. The greater the deviation of the phase regulator from the rated speed, the greater the output machine-end voltage additional set value.

[0048] Embodiment 2, Figure 2 The topological structure diagram of the phase regulator additional excitation system of the present invention is given. Figure 2 The modules and the parameters they contain are explained in detail as follows: the middle control module is the conventional excitation control of the phase regulator, the upper control module is the PSO-GWO-PID feedforward control, and the lower control module is the additional set value control of the terminal voltage.

[0049] in: is the grid voltage, To adjust the voltage at the machine end, To adjust the camera speed, For low excitation control voltage, is the output of the power system stabilizer PSS, is the terminal voltage, is the grid connection point voltage reference value, represents the stable synchronous angular velocity, , , , , , , , , .

[0050] Embodiment 3, Figure 3 The topological structure diagram of the simulation system of the present invention is given, and the MATLAB / Simulink software platform is used according to Figure 3A simulation model was built. The phase regulator was connected to the 35kV bus together with the wind turbine through transformer T1, then stepped up to the 220 kV bus through transformer T2, and then connected to the infinite system through a unidirectional transmission line. A three-phase short-circuit fault was set at the 220kV bus.

[0051] The wind turbine and phase regulator parameter models are shown in Tables 2 and 3.

[0052]

[0053] Table 2 Fan simulation parameters

[0054] Table 3 Phase tunner simulation parameters One of the two phase condenser excitation control methods is the additional control method proposed in this invention, and the other is the conventional phase condenser excitation control as a control group. In order to quantitatively analyze the contribution of the two phase condenser excitation control methods to the system voltage, the dynamic voltage offset , Steady-state voltage loss Dynamic voltage fluctuation size and steady-state voltage loss.

[0055] The dynamic voltage deviation is calculated as: (4) Where: is the dynamic voltage deviation, is the dynamic voltage peak, is the rated voltage.

[0056] The calculation formula for steady-state voltage loss is: (5) Where: is the steady-state voltage loss, is the steady-state voltage value before the fault, is the steady-state voltage recovery value after a fault.

[0057] Embodiment 4, Figure 4 The comparison diagram of the simulation results of the example obtained in the simulation environment of Example 3 is shown. The dynamic voltage deviation calculation formula of formula (4) and the steady-state voltage loss calculation formula of formula (5) are used to calculate the dynamic voltage deviation of the conventional excitation control of the phase regulator and the additional excitation control of the present invention. 0.8% and 0.5% respectively, steady-state voltage loss They are 1.83% and 1.51% respectively.

[0058] The results show that the control method of distributed phase-converter auxiliary excitation system based on PSO-GWO-PID algorithm can not only reduce the dynamic voltage deviation of the phase-converter grid-connected bus voltage, but also reduce the voltage loss in the post-fault recovery stage.

[0059] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0060] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product.

[0061] Those of ordinary skill in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0062] In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0063] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0064] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A control method for a distributed phase-converter auxiliary excitation system taking into account the PSO-GWO-PID algorithm, characterized in that: The following steps are involved: The PID parameters of the feedforward link of the grid-connected bus voltage are preprocessed by combining the particle swarm algorithm, and the optimal PID controller parameters of the feedforward link are obtained based on the grey wolf algorithm. Obtain the first data of the phase regulator, evaluate the transient stability level of the phase regulator in combination with the Lyapunov function, and obtain the additional given value of the terminal voltage; The optimal feedforward link PID controller parameters and the additional set value of the terminal voltage are introduced into the original excitation system of the conventional phase regulator to obtain the additional excitation system of the phase regulator.

2. A distributed phase condenser supplementary excitation system control method taking into account the PSO-GWO-PID algorithm as claimed in claim 1, characterized in that: The PID parameters of the feedforward link of the grid-connected bus voltage are preprocessed by combining the particle swarm algorithm, specifically: Define the population size of the initial particle swarm and the parameter range of the PID parameters of the feedforward link; Within the defined parameter range, a number of particles are randomly generated by combining the preset inertia coefficient and several groups of learning factors to obtain the initial wolf pack; Calculate the fitness of each particle in the initial wolf pack and obtain the initial feedforward link PID controller parameters.

3. A distributed phase condenser additional excitation system control method taking into account the PSO-GWO-PID algorithm as claimed in claim 2, characterized in that: The optimal feedforward link PID controller parameters obtained based on the Grey Wolf algorithm are specifically: Real-time collection of grid-connected bus voltage deviation values ​​under each set of initial feedforward link PID controller parameters; Feeding back the grid-connected bus voltage deviation value to the fitness function of the grey wolf algorithm to obtain several groups of wolf packs with optimal fitness values; Calculate the positions and search directions of the gray wolves in the wolf pack with the best fitness value for several groups of wolves; When the fitness function value of the Grey Wolf Algorithm approaches zero or reaches the maximum number of iterations, the optimal feedforward link PID controller parameters are obtained.

4. A distributed phase condenser supplementary excitation system control method taking into account the PSO-GWO-PID algorithm as claimed in claim 3, characterized in that: The first data of the phase regulator is obtained, and the transient stability level of the phase regulator is evaluated in combination with the Lyapunov function to obtain the additional given value of the terminal voltage, which is specifically: The first phase condenser data includes the phase condenser electromagnetic power and the phase condenser speed deviation; It is set that when the phase modulator terminal voltage is greater than a first preset threshold value and the rate of change of active power is greater than a second preset threshold value, the direction in which the phase modulator electromagnetic power flows to the power grid is a positive direction; If the camera electromagnetic power is positive and the phase shifter speed deviation is positive, the machine terminal voltage additional given value controls the output machine terminal voltage additional given positive value; If the camera electromagnetic power is negative and the phase shifter speed deviation is negative, the machine terminal voltage additional given value controls the output machine terminal voltage additional given positive value; If the camera electromagnetic power is negative and the phase shifter speed deviation is positive, the machine terminal voltage additional given value controls the output machine terminal voltage additional given negative value; If the camera electromagnetic power is positive and the phase shifter speed deviation is negative, the machine terminal voltage additional given value controls the output machine terminal voltage additional given negative value; The magnitude of the additional given positive value of the terminal voltage depends on the offset between the actual speed of the unit and the rated speed and the first set gain, and the additional given positive value of the terminal voltage is set not to be greater than the maximum value of the additional given voltage of the terminal voltage; The magnitude of the additional given negative value of the machine-end voltage depends on the offset between the actual speed and the rated speed of the unit at this time and the second set gain, and the additional given negative value of the machine-end voltage is set to be no less than the additional given minimum value of the machine-end voltage.

5. A distributed phase condenser supplementary excitation system control method taking into account the PSO-GWO-PID algorithm as claimed in claim 4, characterized in that: The optimal feedforward link PID controller parameters and the additional given value of the terminal voltage are introduced into the original excitation system of the conventional phase regulator to obtain the additional excitation system of the phase regulator, which is specifically: The phase condenser additional excitation system includes: phase condenser conventional excitation control, PSO-GWO-PID feedforward control, and terminal voltage additional set value control; The feedforward control superposition of the grid-connected bus output by the PSO-GWO-PID feedforward control is obtained by taking the grid-connected bus voltage error as the feedforward input quantity based on the phase-converter excitation system control strategy of the PSO-GWO-PID algorithm; The machine-end voltage additional given value control outputs the machine-end voltage additional given value in a self-adaptive gain manner. The greater the deviation of the phase regulator from the rated speed, the greater the output machine-end voltage additional given value.

6. A distributed phase condenser supplementary excitation system control method taking into account the PSO-GWO-PID algorithm as claimed in claim 5, characterized in that: The grid-connected bus voltage deviation value is fed back to the fitness function of the grey wolf algorithm to obtain several groups of wolf packs with the best fitness values. The calculation formula is: Where: t represents time, Indicates the deviation between the given voltage value of the grid-connected bus and the actual voltage of the bus.

7. A distributed phase condenser supplementary excitation system control method taking into account the PSO-GWO-PID algorithm as claimed in claim 6, characterized in that: The calculation formula for calculating the positions and search directions of the gray wolves in the wolf pack with the best fitness value of the wolf pack with the best fitness value is specifically as follows: Where: represent The direction of movement of the wolf pack, represent The direction of movement of the wolf pack, represent The direction of movement of the wolf pack, Indicates updating the position of the gray wolf.

8. A distributed phase condenser supplementary excitation system control method taking into account the PSO-GWO-PID algorithm as claimed in claim 7, characterized in that: The first phase modulator data is obtained, and the transient stability level of the phase modulator is evaluated in combination with the Lyapunov function to obtain the additional given value of the terminal voltage. The calculation formula is as follows: Where: For the transient stability level of the phase regulator, represents the steady-state synchronous angular velocity, Indicates the phase shifter speed deviation, Represents the electromagnetic power of the phase regulator.

Images