CN117650583B

CN117650583B - Hydropower station one-pipe multi-machine grid-connection multi-target coordination optimization control method and system

Info

Publication number: CN117650583B
Application number: CN202410126336.6A
Authority: CN
Inventors: 时有松; 程建; 张东峰; 李银斌; 李见辉; 严喆; 陈加威; 陈楠; 杨旋; 苏靖惠; 喻小琴; 马明轩; 李高朋; 杨忠; 高攀
Original assignee: Three Gorges Jinsha River Yunchuan Hydropower Development Co ltd
Current assignee: Three Gorges Jinsha River Yunchuan Hydropower Development Co ltd
Priority date: 2024-01-30
Filing date: 2024-01-30
Publication date: 2024-04-26
Anticipated expiration: 2044-01-30
Also published as: CN117650583A

Abstract

The invention discloses a hydropower station one-pipe multi-machine grid-connected multi-target coordinated optimization control method and a system, which relate to the field of hydropower stations and comprise the steps of coupling a shafting multi-dimensional vibration nonlinear mathematical model into a grid-connected operation speed regulation system mathematical model so as to construct a one-pipe multi-machine grid-connected operation nonlinear mathematical model coupling shafting multi-dimensional vibration of a unit; establishing a multi-objective optimization function considering the adjustment performance of a speed regulation system and the multi-dimensional vibration dynamic performance of a shafting, and selecting disturbance load distribution coefficients and speed regulator control parameters of each unit as optimized decision variables; and optimizing the decision variable by utilizing a multi-objective optimization algorithm to obtain various pareto control schemes meeting the requirements. The invention establishes a model and a theoretical basis for safe and stable regulation and optimization operation of the hydropower station common-tube multi-machine grid-connected operation by establishing the hydropower station one-tube multi-machine grid-connected operation nonlinear mathematical model taking shafting-speed regulation coupling into consideration.

Description

Hydropower station one-pipe multi-machine grid-connection multi-target coordination optimization control method and system

Technical Field

The invention relates to the field of hydropower stations, in particular to a hydropower station one-pipe multi-machine grid-connection multi-target coordination optimization control method and system.

Background

Hydropower is used as a clean renewable energy source, mainly plays roles of peak regulation, frequency modulation and phase modulation in a power grid, and is used as a regulator and a stabilizer of the power grid, the specific gravity of the capacity of the regulator and the stabilizer in a power system is larger and larger, and the regulator and the stabilizer become important struts of a global double-carbon target. The hydropower stations in China are complex in arrangement, and a one-pipe multi-machine arrangement mode for setting pressure regulating facilities is mostly adopted, so that hydraulic co-interference exists in grid-connected operation of each unit, and the difficulty of stable regulation of the units is increased. In addition, the shafting of the unit is used as the core of energy conversion, and the speed regulating system of the hydroelectric unit inevitably causes obvious dynamic response of the shafting in the regulating process, so that the shafting and the speed regulating system are mutually coupled. Meanwhile, the unit shafting is subjected to multiple excitation in the response process, so that the safety and stability of the unit are greatly reduced.

In recent years, china has made great progress in nonlinear vibration characteristics and adjustment control of shafting of hydroelectric generating sets. The method mainly comprises the steps of establishing a unit shafting vibration model, analyzing nonlinear dynamics characteristics of unit shafting vibration under different excitation actions by adopting a rotor dynamics method, or acquiring unit vibration signals by adopting a monitoring sensor, and extracting unit shafting vibration characteristics by adopting a signal noise reduction method. The latter mainly improves the regulation performance by establishing a refined model of the speed regulating system under various control modes and proposing various controllers. Currently, a microcomputer PID speed regulator is mainly adopted in the hydroelectric generating set, and the adjustment control performance of the generating set is improved mainly by acquiring optimal PID control parameters through an intelligent optimization algorithm.

The dynamic adjustment and multi-objective coordination control optimization of the one-pipe multi-machine grid-connected operation of the hydropower station with the shafting and speed regulation coupling of the unit is considered, and the method is an effective method for improving the overall adjustment quality of the unit. The current stable regulation and control of the hydroelectric generating set is greatly progressed, but in the actual regulation and control of the hydroelectric generating set, the coupling characteristic of a shafting and a speed regulation system is ignored, so that the dynamic performance of the shafting of the hydroelectric generating set is ignored in the regulation and optimization control. In addition, the current unit regulation optimization control mainly uses a single machine, omits the hydraulic power common interference characteristic among units, omits the coupling characteristic with a power grid, and greatly reduces the stability and safety of unit regulation.

Disclosure of Invention

The invention is provided in view of the fact that the coupling characteristic of the shafting and the speed regulating system is ignored in the actual regulation control of the existing unit, so that the dynamic performance of the shafting of the unit is ignored in the regulation optimization control.

Therefore, the invention aims to solve the problem of how to establish a hydropower station multi-unit grid-connected speed regulation system model of coupling shafting dynamics so as to realize coordination and optimization control of operation safety and regulation performance.

In order to solve the technical problems, the invention provides the following technical scheme:

In a first aspect, the embodiment of the invention provides a hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method, which comprises the steps of establishing a speed regulation system mathematical model of hydropower station one-pipe multi-machine topological arrangement grid-connected operation, and establishing a unit shafting multidimensional vibration nonlinear mathematical model based on a Lagrange equation; coupling the shafting multidimensional vibration nonlinear mathematical model to a grid-connected operation speed regulation system mathematical model to construct a one-pipe-multimachine grid-connected operation nonlinear mathematical model coupling shafting multidimensional vibration of the unit; establishing a multi-objective optimization function considering the adjustment performance of a speed regulation system and the multi-dimensional vibration dynamic performance of a shafting, and selecting disturbance load distribution coefficients and speed regulator control parameters of each unit as optimized decision variables; optimizing the decision variable by using an NSGA-III multi-objective optimization algorithm to obtain various pareto control schemes meeting the requirements; evaluating and analyzing all the control schemes by using a fuzzy satisfaction evaluation method, and selecting a scheme with highest standardized satisfaction as a final coordinated optimization control scheme; and dynamically adjusting response characteristics of the unit of the highest standardized satisfaction scheme and the lowest standardized satisfaction scheme through simulation contrast analysis so as to verify the effectiveness of the proposed coordination control strategy.

As a preferable scheme of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method, the invention comprises the following steps: the method for establishing the mathematical model of the speed regulation system for the one-pipe multi-machine topological arrangement grid-connected operation of the hydropower station comprises the following steps: establishing a subsystem mathematical model, wherein the subsystem mathematical model comprises a diversion tunnel equation, a pressure regulating chamber continuity equation, a common pipe pressure pipeline equation, a branch pipe flow continuity equation, a branch pipe pressure pipeline equation of each unit, a hydraulic turbine moment flow equation of each unit, a generator equation of each unit, a speed regulator equation of each unit and a power grid equivalent equation; according to the physical connection and operation characteristics among all subsystems, all subsystem mathematical models are combined to construct an integral hydropower station one-pipe multi-machine grid-connected operation speed regulation system mathematical model; the specific formula of the mathematical model of the hydropower station one-pipe multi-machine grid-connected operation speed regulation system is as follows:

wherein, Representing the inertial time constant of water flow of diversion tunnel,/>Representing head loss of diversion tunnel,/>Representing the rated head,/>Representing the relative value of flow deviation of diversion tunnel,/>Representing the flow deviation relative value of branch pipes of each unit,/>Representing inertial time constant of each unit,/>Representing the time constant of the pressure regulating chamber,/>Representing the inertia time constant of water flow of a common pressure pipeline,/>Representing the inertia time constant of water flow of each branch pipe,/>Representing the equivalent load self-regulating coefficient of the power grid,/>Representing the time constant of the equivalent servomotor of the power grid,/>Representing the equivalent inertial time constant of the power grid,/>Representing the equivalent permanent state slip coefficient of the power grid,/>Representing pressure line loss,/>Representing the head loss of branch pipes of each unit,/>Respectively representing the deviation relative values of the rotating speed, the opening degree of the guide vane, the power moment of the water turbine and the resistance moment of the generator of each unitRepresenting the moment transfer coefficient of each water turbine,/>Representing the flow transfer coefficient of each water turbine,/>Representing the response time constant of each servomotor,/>Respectively representing the proportional gain and the integral gain of each speed regulator,/>Representing the load self-regulating coefficient of each generator,Representing the equivalent synchronous coefficient of each generator,/>Representing the relative value of flow deviation of a shared pipeline,/>Representing the power angle of each generator,/>Representing the equivalent damping coefficient of each generator,/>Representing the relative value of the frequency deviation of the power grid,/>Meaning intermediate variables are of no particular significance,/>The method is characterized in that the method comprises the steps of representing disturbance load of a power grid, i representing a unit number, B representing the ratio of hydroelectric unit power in the power grid, n representing the number of branch pipes, t representing time, and z representing the relative value of water level deviation of a pressure regulating chamber.

As a preferable scheme of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method, the invention comprises the following steps: the nonlinear mathematical model for building the multi-dimensional vibration of the unit shafting comprises the following steps: according to the shafting structure of the hydroelectric generating set, the geometric position relation among the rotor, the rotating wheel and the guide bearing is established, and the specific formula is as follows:

wherein, Representing shafting dimension parameter,/>The vibration radii of the generator rotor, the turbine runner, the upper guide bearing, the lower guide bearing and the water guide bearing are respectively represented.

The method comprises the steps of establishing a hydro-generator set shafting multidimensional vibration kinetic energy equation T and a set shafting multidimensional vibration potential energy equation U, wherein the specific formulas are as follows:

wherein, Representing the centroid coordinates of the generator rotor,/>Representing the barycentric coordinates of the turbine runner,/>Respectively represent the rotational inertia of the generator rotor and the turbine runner,/>Respectively represent the concentrated mass of the generator rotor and the turbine runner,/>Respectively representing the eccentricity of the generator rotor and the turbine runner,Respectively representing the rotation angles of the generator rotor and the turbine runner,/>Respectively represent the equivalent mass of the generator rotor and the turbine runner,/>Respectively representing the vibration speeds of the generator rotor and the turbine runner,/>The rotational angular velocities of the generator rotor and the runner are represented, respectively.

Wherein,Representing the centroid coordinates of the generator rotor,/>Representing the barycentric coordinates of the turbine runner,/>Respectively representing the rotation angles of the generator rotor and the turbine runner,/>Respectively represent the equivalent mass of the generator rotor and the turbine runner,/>Representing gravitational acceleration,/>Representing axial stiffness,/>Representing thrust guide bearing stiffness,/>Expressed as axle torsional stiffness,/>Representing the equivalent stiffness of the shafting.

Adding damping as a linear factor into a generator rotor and a turbine runner, and simultaneously considering various external force excitations to the rotor and the runner; equation of kinetic energyPotential energy equation/>Substituting the external force excitation into a Lagrange equation to deduce a nonlinear mathematical model of the shafting multidimensional vibration of the hydroelectric generating set; the specific formula of the nonlinear mathematical model of the shafting multidimensional vibration of the hydroelectric generating set is as follows:

the specific formula of the nonlinear mathematical model of the shafting multidimensional vibration of the hydroelectric generating set is as follows:

Wherein i represents the number of the unit, Respectively represent unbalanced magnetic tension in x and y directions of generator rotor with unit number of i,/>, andArcuate turning forces in x and y directions of generator rotor with unit number i are respectively expressed, iThe oil film forces of the upper guide bearings in the x and y directions of the generator rotor with the unit number i are respectively shown,Oil film force of down-guide bearing of generator rotor with unit number i in x and y directions is expressed respectively,/>Representing the axial resultant force of unit number i,/>Sealing exciting forces in x and y directions of turbine runner with unit number i are respectively expressed, and the sealing exciting forces are expressed by/>Respectively represents hydraulic unbalance force of the turbine runner with the unit number i in the x and y directions,Vortex belt eccentric force in x and y directions of turbine runner with unit number i is expressed respectively,/>Respectively representing bow-shaped turning force in x and y directions of turbine runner with unit number i,/>The oil film force of the water guide bearing in the x and y directions of the turbine runner with the unit number i is respectively expressed, and the oil film force is/Represents the axial water thrust of the unit number i,/>Respectively representing the mass of a generator rotor and a turbine runner with the unit number of i,/>Represents the equivalent concentrated mass of the generator rotor with the unit number i and the rotating shaft thereof, the turbine runner and the rotating shaft thereof,Respectively representing the mass center coordinates of a generator rotor and a turbine runner with the unit number of i,/>Respectively representing the rotation angles of the generator rotor with the unit number of i and the turbine runner,Respectively represents the equivalent rigidity of shafting with unit number i,/>Respectively representing the eccentricity of the generator rotor with the unit number i and the turbine runner,/>Represents the axial stiffness of the unit number i,/>Represents the rigidity of a thrust guide bearing with the unit number of i,/>Represents the torsional stiffness of the shaft with the unit number i,/>Respectively representing the rotational inertia of a generator rotor with the unit number of i and the rotational inertia of a turbine runner of a water turbineRespectively representing the moment of the generator rotor and the turbine runner with the unit number of i,/>Damping coefficient of generator rotor and turbine runner respectively representing unit number i,/>Indicating the torsion angle of the unit number i,/>Respectively representing the vibration speeds of the generator rotor with the unit number of i and the turbine runner,Vibration acceleration of generator rotor and turbine runner respectively indicated by unit number i,/>Respectively representing the rotation angular velocity of the generator rotor with the unit number of i and the turbine runner,The rotational angular accelerations of the generator rotor and the turbine runner are respectively indicated by the unit number i.

As a preferable scheme of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method, the invention comprises the following steps: a tube multi-machine grid-connected operation nonlinear mathematical model comprises the following steps: the method comprises the following steps of establishing a unit rotation equation considering unit shafting-speed regulation coupling, wherein the specific formula is as follows:

wherein, Representing the flow deviation relative value of branch pipes of each unit,/>The relative value of the flow deviation of the diversion tunnel is expressed,Representing the moment transfer coefficient of each water turbine,/>The flow transfer coefficient of each water turbine is represented,Representing the equivalent synchronous coefficient of the generator i,/>Represents the equivalent damping coefficient of the generator i,/>Representing the relative value of the resistance moment deviation of the generator with the unit number of i,/>Representing the rotation angular velocity base value,/>Representing the relative value of frequency deviation of unit number i,/>Representing the rated power of the unit i,/>Respectively representing vibration acceleration of a generator rotor and a rotating wheel with unit numbers i;

the method comprises the following steps of obtaining a mathematical model of a parallel grid-connected operation speed regulation system, a multidimensional vibration nonlinear mathematical model of each unit shafting, and a unit rotation equation which considers unit shafting-speed regulation coupling so as to obtain a one-tube multi-machine grid-connected operation nonlinear mathematical model which couples the multidimensional vibration of the unit shafting, wherein the specific formula is as follows:

wherein, Representing the inertial time constant of water flow of diversion tunnel,/>Representing head loss of diversion tunnel,/>Representing the rated head,/>Representing the relative value of flow deviation of diversion tunnel,/>Representing the flow deviation relative value of branch pipes of each unit,/>Representing inertial time constant of each unit,/>Representing the time constant of the pressure regulating chamber,/>Representing the inertia time constant of water flow of a common pressure pipeline,/>Representing the inertia time constant of water flow of each branch pipe,/>Representing the equivalent load self-regulating coefficient of the power grid,/>Representing the time constant of the equivalent servomotor of the power grid,/>Representing the equivalent inertial time constant of the power grid,/>Representing the equivalent permanent state slip coefficient of the power grid,/>Representing pressure line loss,/>Representing the head loss of branch pipes of each unit,/>Respectively representing the deviation relative values of the rotating speed, the opening degree of the guide vane, the power moment of the water turbine and the resistance moment of the generator of each unitRepresenting the moment transfer coefficient of each water turbine,/>Representing the flow transfer coefficient of each water turbine,/>Representing the response time constant of each servomotor,/>Respectively representing the proportional gain and the integral gain of each speed regulator,/>Representing the load self-regulating coefficient of each generator,Representing the equivalent synchronous coefficient of each generator,/>Representing the relative value of flow deviation of a shared pipeline,/>Representing the power angle of each generator,/>Representing the equivalent damping coefficient of each generator,/>Representing the relative value of the frequency deviation of the power grid,/>Meaning intermediate variables are of no particular significance,/>The method is characterized in that the method comprises the steps of representing disturbance load of a power grid, i representing a unit number, B representing the ratio of hydroelectric unit power in the power grid, n representing the number of branch pipes, t representing time, z representing the relative value of water level deviation of a pressure regulating chamber, and/(o)Respectively represent unbalanced magnetic tension in x and y directions of generator rotor with unit number of i,/>, andArcuate turning forces in x and y directions of generator rotor with unit number i are respectively expressed, iOil film force of upper guide bearing of generator rotor in x and y directions with unit number i is expressed respectively,/>The oil film forces of the down guide bearings in the x and y directions of the generator rotor with the unit number i are respectively shown,Representing the axial resultant force of unit number i,/>Sealing exciting forces in x and y directions of turbine runner with unit number i are respectively expressed, and the sealing exciting forces are expressed by/>Respectively representing hydraulic unbalance force in x and y directions of turbine runner with unit number i,/>Vortex belt eccentric force in x and y directions of turbine runner with unit number i is expressed respectively,/>Respectively representing bow-shaped turning force in x and y directions of turbine runner with unit number i,/>The oil film force of the water guide bearing in the x and y directions of the turbine runner with the unit number i is respectively expressed, and the oil film force is/Represents the axial water thrust of the unit number i,/>Respectively representing the mass of a generator rotor and a turbine runner with the unit number of i,/>Represents the equivalent concentrated mass of the generator rotor with the unit number i and the rotating shaft thereof, the turbine runner and the rotating shaft thereof,Respectively representing the mass center coordinates of a generator rotor and a turbine runner with the unit number of i,/>Respectively representing the rotation angles of the generator rotor with the unit number of i and the turbine runner,Respectively represents the equivalent rigidity of shafting with unit number i,/>Respectively representing the eccentricity of the generator rotor with the unit number i and the turbine runner,/>Represents the axial stiffness of the unit number i,/>Represents the rigidity of a thrust guide bearing with the unit number of i,/>Represents the torsional stiffness of the shaft with the unit number i,/>Respectively representing the rotational inertia of a generator rotor with the unit number of i and the rotational inertia of a turbine runner of a water turbineRespectively representing the moment of the generator rotor and the turbine runner with the unit number of i,/>Damping coefficient of generator rotor and turbine runner respectively representing unit number i,/>Indicating the torsion angle of the unit number i,/>Respectively representing the vibration speeds of a generator rotor and a turbine runner with unit numbers of i,/>Vibration acceleration of generator rotor and turbine runner respectively indicated by unit number i,/>Respectively representing the rotation angular velocity of a generator rotor and a turbine runner with unit number i,/>The rotational angular accelerations of the generator rotor and the turbine runner are respectively indicated by the unit number i.

As a preferable scheme of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method, the invention comprises the following steps: the establishment of a multi-objective optimization function considering the system regulation performance and shafting multi-dimensional vibration comprises the following principles: taking the integral of the absolute error and time as the minimum overshoot and the minimum adjustment time performance evaluation of the dynamic response output of each system, and the specific formula is as follows:

Where t represents time.

The method comprises the steps of establishing a multi-objective optimization function which aims at minimum overshoot and minimum adjustment time of frequency response and shafting multi-dimensional vibration response of each unit, wherein the specific formula is as follows:

wherein, Represents the controller proportional gain of unit i,/>Representing the controller integral gain of the unit i,Representing the integral of the absolute error of the frequency of the unit i with time,/>Respectively representing the integral of the absolute error of the vibration radius of the unit i shafting rotor and the rotating wheel and the time,/>Representing the duty ratio of each unit,/>Representing the weights of the indexes,/>Each unit dynamic response target 1 is represented, and i represents a unit number.

The method comprises the steps of establishing a multi-objective optimization function which aims at minimum overshoot and minimum adjustment time of the water levels of a power grid and a pressure regulating chamber, wherein the specific formula is as follows:

wherein, Represents the controller proportional gain of unit i,/>Representing the controller integral gain of unit i,/>Representing the load duty ratio of the unit i,/>Representing the dynamic response objective 2,/>, of the systemRepresenting the integral of the absolute error of the grid frequency with time,/>Indicating the absolute error of the pressure regulating chamber water level and the time integral.

As a preferable scheme of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method, the invention comprises the following steps: obtaining a plurality of pareto control schemes meeting requirements comprises the following steps: the value range and the constraint condition of the decision variable are defined; according to the complexity of the problem and the convergence requirement of the algorithm, determining the optimized population quantity and the maximum iteration number of NSGA-III; randomly initializing a population according to a decision variable range, and uniformly distributing the population in a target space to generate reference points; carrying out rapid non-dominant sorting on the population, and calculating the crowding distance and the association degree between each individual and each reference point; selecting by combining non-dominant ranking, crowding distance and association degree to generate sub-populations, and performing crossover and mutation operations on the selected populations to generate new populations; carrying out cluster selection on the population according to the association degree and the reference point, and carrying out iterative optimization until the maximum iterative times are met; and selecting an individual with higher relevance from the final non-dominant set as the pareto optimal solution set.

As a preferable scheme of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method, the invention comprises the following steps: the fuzzy satisfaction evaluation method comprises the following steps: according to the influence condition of satisfaction of each objective function, a fuzzy membership function is selected, and the specific formula is as follows:

wherein, Representing i target,/>Representing the maximum fitness value,/>And represents the minimum fitness value, and j represents the number of non-inferior solutions.

Mapping a plurality of objective function values of each control scheme to corresponding membership functions, and calculating the standardized satisfaction of each objective, wherein the specific formula is as follows:

wherein, Representing fuzzy satisfaction,/>And (3) representing standardized satisfaction values of all schemes, and m represents an optimized number target.

And sorting according to the standardized satisfaction degree of all the control schemes, and selecting the control scheme with the maximum standardized satisfaction degree.

In a second aspect, the embodiment of the invention provides a hydropower station one-pipe multi-machine grid-connected multi-target coordinated optimization control system, which comprises a mathematical model module, a control module and a control module, wherein the mathematical model module is used for constructing a hydropower station one-pipe multi-machine grid-connected operation speed regulation system mathematical model, a hydroelectric generating set shafting multidimensional vibration nonlinear mathematical model and a hydropower station one-pipe multi-machine grid-connected operation nonlinear mathematical model taking shafting-speed regulation coupling into consideration; the control optimization module is used for establishing a multi-objective optimization function so as to reduce the frequency of each unit, the multidimensional vibration of a shafting, the water level of a pressure regulating chamber and the overshoot of the frequency response of a power grid as far as possible and minimize the adjustment time; and the simulation analysis module is used for carrying out simulation analysis on dynamic response characteristics of the typical control scheme with the highest standardized satisfaction and the lowest standardized satisfaction.

In a third aspect, embodiments of the present invention provide a computer apparatus comprising a memory and a processor, the memory storing a computer program, wherein: when the computer program is executed by a processor, any step of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method according to the first aspect of the invention is realized.

In a fourth aspect, embodiments of the present invention provide a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, any step of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method according to the first aspect of the invention is realized.

The invention has the beneficial effects that: the invention establishes a model and a theoretical basis for safe and stable regulation and optimization operation of the hydropower station common-tube multi-machine grid-connected operation by establishing a nonlinear mathematical model of the hydropower station one-tube multi-machine grid-connected operation taking shafting-speed regulation coupling into consideration; the multi-objective coordinated control optimization method for the one-pipe multi-machine grid-connected operation of the hydropower station provided by the invention considers the coordinated distribution of disturbance loads among all units, and simultaneously considers the dynamic performance of multi-dimensional vibration of a shafting in the adjusting process of the units, so that the dynamic adjusting performance of each unit, a voltage regulating room and the frequency of a power grid is integrally improved, and technical support is provided for safe and stable operation of the hydropower units and the power grid.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart of multi-objective coordinated control optimization analysis of a hydropower station one-pipe multi-machine grid-connected multi-objective coordinated optimization control method.

Fig. 2 is a schematic diagram of a hydropower station one-pipe-multiple-machine arrangement of a hydropower station one-pipe-multiple-machine grid-connection multi-target coordination optimization control method.

FIG. 3 is a diagram of a hydropower station one-pipe-multiple-machine grid-connected multi-objective coordinated optimization control framework of a hydropower station one-pipe-multiple-machine grid-connected dynamic process multi-objective coordinated control optimization control method.

Fig. 4 is a shafting structure diagram of a hydroelectric generating set by a hydropower station one-pipe multi-machine grid-connection multi-target coordination optimization control method.

FIG. 5 is a NSGA-III multi-objective optimization flow chart of a hydropower station one-pipe multi-machine grid-connected multi-objective coordination optimization control method.

FIG. 6 shows the pareto front of the multi-objective optimization result of the one-pipe multi-machine grid-connected multi-objective coordination optimization control method of the hydropower station.

FIG. 7 is a diagram of normalized satisfaction of a multi-objective optimization scheme for a hydropower station one-pipe multi-machine grid-connected multi-objective coordinated optimization control method.

FIG. 8 is a time domain diagram of dynamic response of the water level of the surge chamber of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method.

FIG. 9 is a time domain diagram of dynamic response of power grid frequency of a hydropower station one-pipe-multiple-machine grid-connected multi-objective coordination optimization control method.

FIG. 10 is a time domain diagram of the frequency dynamic response of the No. 1 unit of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method.

FIG. 11 is a time domain diagram of the frequency dynamic response of the No.2 unit of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method.

Fig. 12 is a dynamic response time domain diagram of the vibration radius of the rotor of the No. 1 machine of the hydropower station one-pipe multi-machine grid-connection multi-target coordination optimization control method.

FIG. 13 is a dynamic response time domain diagram of the vibration radius of the No. 1 machine runner of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method.

Fig. 14 is a dynamic response time domain diagram of the vibration radius of the rotor of the No. 2 machine of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method.

FIG. 15 is a dynamic response time domain diagram of the vibration radius of the No. 2 machine runner of the hydropower station one-pipe multi-machine grid-connected multi-target coordination optimization control method.

Detailed Description

In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways other than those described herein, and persons skilled in the art will readily appreciate that the present invention is not limited to the specific embodiments disclosed below.

Further, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic can be included in at least one implementation of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

Example 1

Referring to fig. 1-15, a first embodiment of the present invention provides a highly confidential office file cabinet,

S1: and establishing a mathematical model of a grid-connected operation speed regulation system of the hydropower station with one-pipe multi-machine topological arrangement, and establishing a nonlinear mathematical model of multi-dimensional vibration of a unit shafting based on a Lagrange equation.

Further, establishing mathematical models of all subsystems, including a diversion tunnel equation, a pressure regulating chamber continuity equation, a pressure pipeline equation, a flow continuity equation at a branch pipe, pressure pipeline equations of all units, torque flow equations of all unit water turbines, generator equations of all units, speed regulator equations of all units and power grid equivalent equations.

Specifically, the specific formula of the diversion tunnel equation is as follows:

wherein, Representing the inertial time constant of water flow of diversion tunnel,/>Expressed as the head loss of the diversion tunnel,Represents the rated water head, t represents the time,/>The relative value of the flow deviation of the diversion tunnel is represented, and z represents the relative value of the water level deviation of the pressure regulating chamber.

Further, the specific formula of the surge chamber equation is as follows:

wherein, Representing the time constant of the pressure regulating chamber,/>Representing the relative value of flow deviation of a shared pipeline,/>The relative value of the flow deviation of the diversion tunnel is represented, and z represents the relative value of the water level deviation of the pressure regulating chamber.

Further, the specific formula of the pressure pipeline equation is as follows:

wherein, Representing the inertia time constant of water flow of a common pressure pipeline,/>Representing pressure line loss,/>Representing the relative value of flow deviation of a shared pipeline,/>The relative value of the common pipeline water head deviation is shown, and z is the relative value of the pressure regulating chamber water level deviation.

Preferably, the specific formula of the flow continuity equation at the branch pipe is as follows:

wherein, Representing the relative value of the flow of the shared pipeline,/>The flow deviation relative value of each unit branch pipe is shown, and n is the number of branch pipes.

Further, the specific formula of the pressure pipeline equation of each unit is as follows:

wherein, Representing the flow deviation relative value of branch pipes of each unit,/>Representing the rated head,/>Representing the head loss of the branch pipe,/>Representing the relative value of the deviation of the water head of the common pipeline,/>Representing the relative value of the water head deviation of each unitThe inertia time constant of the water flow of each branch pipe is shown, and i is the unit number.

Preferably, the specific formula of the moment flow equation of the hydraulic turbine of each unit is as follows:

wherein, Respectively represent the moment transfer coefficient of the hydraulic turbine of the unit i,/>Respectively represent flow transmission coefficients,/>Representing the deviation relative value of the rotating speed of the unit i/>Representing the water head deviation of each unit/>Representing the relative value of the opening deviation of the guide vane of the unit i,/>Representing the flow deviation relative value of branch pipes of each unit,/>And the relative value of the torque deviation of the hydraulic turbine of the unit i is represented.

Further, the specific formula of each unit generator equation is as follows:

Wherein i represents the number of the unit, Represent the inertial time constant of the hydroelectric generating set,/>Representing the deviation relative value of the rotating speed of the unit,/>Representing the relative value of the frequency deviation of the power grid,/>Representing the load self-regulating coefficient,/>Representing equivalent damping coefficient of unit number i,/>Representing the power angle of the generator,/>And the relative value of the torque deviation of the hydraulic turbine of the unit i is represented.

Further, the specific formula of the speed regulator equation of each unit is as follows:

wherein, Represents the opening degree of the guide vane of the unit i,/>Respectively representing the proportional and integral gains,/>Indicating the relative deviation value of the rotational speed of the unit.

Preferably, the specific formula of the grid equivalent equation is as follows:

wherein, Representing the equivalent inertial time constant of the power grid,/>Representing the relative value of the frequency deviation of the power grid, and B representing the ratio of the power of the hydroelectric generating set in the power grid,/>Representing the time constant of the equivalent servomotor of the power grid,/>Representing the equivalent permanent state slip coefficient of the power grid,Representing grid load,/>Representing the relative value of disturbance load of power grid,/>The intermediate variables are not particularly meant.

It should be noted that the number of the substrates,、/>、/>AndRespectively representing the relative values of the unit rotating speed, the opening degree of the guide vane, the power moment of the water turbine and the resistance moment deviation of the generator,/>、/>、、/>、/>、Respectively represent the relative values of the deviations of the respective variables.

Furthermore, the basic equation of the mathematical model of the hydropower station subsystem is combined to obtain the mathematical model of the hydropower station one-pipe multi-machine grid-connected operation speed regulation system, and the specific formula is as follows:

wherein, Representing the inertial time constant of water flow of diversion tunnel,/>Representing head loss of diversion tunnel,/>Representing the rated head,/>Representing the relative value of flow deviation of diversion tunnel,/>Representing the flow deviation relative value of branch pipes of each unit,/>Representing inertial time constant of each unit,/>Representing the time constant of the pressure regulating chamber,/>Representing the inertia time constant of water flow of a common pressure pipeline,/>Representing the inertia time constant of water flow of each branch pipe,/>Representing the equivalent load self-regulating coefficient of the power grid,/>Representing the time constant of the equivalent servomotor of the power grid,/>Representing the equivalent inertial time constant of the power grid,/>Representing the equivalent permanent state slip coefficient of the power grid,/>Representing pressure line loss,/>Representing the head loss of branch pipes of each unit,/>Respectively representing the deviation relative values of the rotating speed, the opening degree of the guide vane, the power moment of the water turbine and the resistance moment of the generator of each unitRepresenting the moment transfer coefficient of each water turbine,/>Representing the flow transfer coefficient of each water turbine,/>Representing the response time constant of each servomotor,/>Respectively representing the proportional gain and the integral gain of each speed regulator,/>Representing the load self-regulating coefficient of each generator,Representing the relative value of flow deviation of a shared pipeline,/>Representing the power angle of each generator,/>Representing the relative value of the frequency deviation of the power grid,/>Meaning intermediate variables are of no particular significance,/>The method is characterized in that the method comprises the steps of representing disturbance load of a power grid, i representing a unit number, B representing the ratio of hydroelectric unit power in the power grid, n representing the number of branch pipes, t representing time, and z representing the relative value/>, of water level deviation of a pressure regulating chamberRepresenting equivalent damping coefficient,/>The equivalent synchronous coefficient is represented by the following specific formula:

wherein I represents the stator current, j represents the imaginary sign, Indicating the rotation speed of the unit,/>Representing the voltage of the bus of the power grid,Representing the q-axis sub-transient reactance,/>Representing q-axis super-transient reactance,/>Representing the q-axis transient voltage,/>Representing the q-axis sub-transient reactance,/>Representing q-axis super-transient reactance,/>Represents the q-axis damping winding time constant,/>Represents the q-axis damping winding time constant,/>Represents leakage reactance,/>Representing the power angle,/>Representing the grid voltage.

Wherein,Representing the transient potential of the generator,/>Representing the q-axis sub-transient reactance,/>Indicating the rotation speed of the unit,/>Representing the power angle,/>Is equivalent to synchronous coefficient,/>Representing the q-axis transient voltage,/>Representing the grid bus voltage.

Preferably, according to the shafting structure of the water turbine generator set, the geometric relationship among the shafting rotor, the rotating wheel and the guide bearing of the water turbine generator set is established, and the specific formula is as follows:

Further, a multi-dimensional vibration kinetic energy and potential energy equation of a water turbine generator set shafting is established, wherein the specific formula of the multi-dimensional vibration kinetic energy equation of the set shafting is as follows:

/>

Specifically, the specific formula of the multi-dimensional vibration potential energy equation of the unit shafting is as follows:

wherein, Representing the centroid coordinates of the generator rotor,/>Representing the barycentric coordinates of the turbine runner,/>Respectively representing the rotation angles of the generator rotor and the turbine runner,/>Respectively represent the equivalent mass of the generator rotor and the turbine runner,/>Representing gravitational acceleration,/>Representing axial stiffness,/>Representing thrust guide bearing stiffness,/>Expressed as axle torsional stiffness,/>The equivalent rigidity of the shafting is represented by the following specific formula:

wherein, Respectively represent the rigidity of the upper, lower and water guide bearings,/>Represents the torsional stiffness of the shaft, E represents the elastic modulus of the main shaft,/>Representing the inner and outer diameters of the main shaft,/>Representing the length of the principal axis,/>Representing axial stiffness,/>Representing thrust guide bearing stiffness,/>Respectively represent shafting parameters, and/>，/>，。

In particular, the torsional stiffness of the shaftWherein E represents the modulus of elasticity of the main shaft,Representing the inner and outer diameters of the main shaft,/>Represents the length of the main shaft, and/>，/>Represents axial rigidity, and。

Furthermore, the damping of the unit shafting is simplified into linear damping to be applied to the generator rotor and the turbine runner, and meanwhile, the generator rotor is considered to be mainly subjected to unbalanced magnetic tensionArcuate rotation of rotor/>Oil film force of upper and lower guide bearings/>Resultant axial force/>Equal external force excitation, the turbine runner is mainly subjected to sealing excitation force/>Unbalanced force of hydraulic powerThe eccentric force P of the vortex belt and the bow-shaped rotation of the runner of the water turbine/>Oil film force of Water guide bearing/>Axial thrust/>And (5) exciting by an external force.

Further, kinetic energy, potential energy equation and external excitation of the set shafting are substituted into the Lagrange equation to obtain multidimensional vibration nonlinear mathematical models of the water turbine generator set shafting, and the specific formula is as follows:

Wherein i represents the number of the unit, Respectively represent unbalanced magnetic tension in x and y directions of generator rotor with unit number of i,/>, andArcuate turning forces in x and y directions of generator rotor with unit number i are respectively expressed, iThe oil film forces of the upper guide bearings in the x and y directions of the generator rotor with the unit number i are respectively shown,Oil film force of down-guide bearing of generator rotor with unit number i in x and y directions is expressed respectively,/>Representing the axial resultant force of unit number i,/>Sealing exciting forces in x and y directions of turbine runner with unit number i are respectively expressed, and the sealing exciting forces are expressed by/>Respectively represents hydraulic unbalance force of the turbine runner with the unit number i in the x and y directions,Vortex belt eccentric force in x and y directions of turbine runner with unit number i is expressed respectively,/>Respectively representing bow-shaped turning force in x and y directions of turbine runner with unit number i,/>The oil film force of the water guide bearing in the x and y directions of the turbine runner with the unit number i is respectively expressed, and the oil film force is/Represents the axial water thrust of the unit number i,/>Respectively representing the mass of a generator rotor and a turbine runner with the unit number of i,/>Represents the equivalent concentrated mass of the generator rotor with the unit number i and the rotating shaft thereof, the turbine runner and the rotating shaft thereof,Respectively representing the mass center coordinates of a generator rotor and a turbine runner with the unit number of i,/>Respectively representing the rotation angles of the generator rotor with the unit number of i and the turbine runner,Respectively represents the equivalent rigidity of shafting with unit number i,/>Respectively representing the eccentricity of the generator rotor with the unit number i and the turbine runner,/>Represents the axial stiffness of the unit number i,/>Represents the rigidity of a thrust guide bearing with the unit number of i,/>Represents the torsional stiffness of the shaft with the unit number i,/>Respectively representing the rotational inertia of a generator rotor with the unit number of i and the rotational inertia of a turbine runner of a water turbineRespectively representing the moment of the generator rotor and the turbine runner with the unit number of i,/>Damping coefficient of generator rotor and turbine runner respectively representing unit number i,/>Indicating the torsion angle of the unit number i,/>Respectively representing the vibration speeds of a generator rotor and a turbine runner with unit numbers of i,/>Vibration acceleration of generator rotor and turbine runner respectively indicated by unit number i,/>Respectively representing the rotation angular velocity of a generator rotor and a turbine runner with unit number i,/>The rotational angular accelerations of the generator rotor and the turbine runner are respectively indicated by the unit number i.

S2: and coupling the nonlinear mathematical model to a grid-connected operation speed regulation system mathematical model to construct a one-pipe multi-machine grid-connected operation nonlinear mathematical model coupled with multi-dimensional vibration of a unit shafting.

Specifically, the method comprises the following steps:

s2.1: and establishing a hydroelectric generating set rotation equation considering multi-dimensional vibration of a set shafting.

Specifically, it willThe operation can be obtained:

wherein, Representing the moment of inertia of the unit i,/>Representing rotational angular velocity,/>Respectively represents the moment of the generator water turbine of the unit i and/>。

Further, the above equation is rewritten by considering the transient change of the rotation angular velocity after the unit is disturbed:

Wherein due to 、/>Therefore, the angular velocity and the rotational speed are dynamically changed，/>Representing the basic value of the moment of the generator,The rotation angular velocity base value is represented.

In particular, wherein、/>、、/>The specific formula of the inertial time constant of the unit is as follows:

/>

wherein, Indicating the rated power of the unit i.

S2.2: will beAnd/>Substituted into the above formula and rewrittenAnd/>Meanwhile, the load self-regulating factor is considered, the moment flow equation of the water turbine is substituted into the set rotation equation of the shafting-speed regulation coupling considered, and the specific formula is as follows:

wherein, Representing the flow deviation relative value of branch pipes of each unit,/>The relative value of the flow deviation of the diversion tunnel is expressed,Representing the moment transfer coefficient of each water turbine,/>The flow transfer coefficient of each water turbine is represented,Representing the equivalent synchronous coefficient of the generator i,/>Represents the equivalent damping coefficient of the generator i,/>Representing the relative value of the resistance moment deviation of the generator with the unit number of i,/>Representing the rotation angular velocity base value,/>Representing the relative value of frequency deviation of unit number i,/>Representing the rated power of the unit i,/>Respectively represent the vibration acceleration of the generator rotor and the rotating wheel with the unit number of i, and/>，/>。

S2.3: the mathematical model of the one-pipe multi-machine grid-connected operation speed regulation system of the hydropower station, the multidimensional vibration nonlinear mathematical model of each unit shafting, and the unit rotation equation of shafting-speed regulation coupling can be used for obtaining the one-pipe multi-machine grid-connected operation nonlinear mathematical model of the hydropower station by taking the unit shafting-speed regulation coupling into consideration, and the specific formula is as follows:

S3: and establishing a multi-objective optimization function considering the system regulation performance and shafting multi-dimensional vibration, and selecting disturbance load distribution coefficients and speed regulator control parameters of each unit as decision variables of multi-objective optimization.

Specifically, the absolute error is integrated with time (i.eCriteria), as minimum overshoot and minimum settling time performance evaluation of dynamic response output of each system, the specific formula is as follows:

Where t represents time.

Further, the minimum frequency of each unit, minimum overshoot of the multidimensional vibration response of the shafting and the shortest adjusting time are taken as target optimization functions, and the specific formula is as follows:

In the present invention，/>，/>Indicating the order of magnitude of the signal,。

Further, an optimization objective function considering the minimum water level overshoot and the shortest adjustment time of the power grid and the pressure regulating chamber is established, and the specific formula is as follows:

S4: and optimizing the decision variable by using an NSGA-III multi-objective optimization algorithm to obtain a plurality of pareto optimal control schemes meeting the requirements.

Specifically, according to a hydropower station one-pipe multi-machine grid-connected operation nonlinear mathematical model taking shafting-speed regulation coupling into consideration, the established multi-objective is optimized to obtain various control schemes, and the method specifically comprises the following steps of: determining the boundary of the decision variable; and determining the number of optimized populations as 30, the iteration times as 50, and programming in a MATLAB environment to optimize a control scheme according to the NSGA-III algorithm flow.

Preferably, the value range and the constraint condition of the decision variable are defined; according to the complexity of the problem and the convergence requirement of the algorithm, determining the optimized population quantity and the maximum iteration number of NSGA-III; randomly initializing a population according to a decision variable range, and uniformly distributing the population in a target space to generate reference points; carrying out rapid non-dominant sorting on the population, and calculating the crowding distance and the association degree between each individual and each reference point; selecting by combining non-dominant ranking, crowding distance and association degree to generate sub-populations, and performing crossover and mutation operations on the selected populations to generate new populations; carrying out cluster selection on the population according to the association degree and the reference point, and carrying out iterative optimization until the maximum iterative times are met; and selecting an individual with higher relevance from the final non-dominant set as the pareto optimal solution set.

S5: and (3) evaluating and analyzing all the control schemes by using a fuzzy satisfaction evaluation method, and selecting the scheme with the highest standardized satisfaction as a final coordinated optimization control strategy.

Specifically, a fuzzy membership function and fuzzy satisfaction of each scheme are constructed, and the specific formula is as follows:

Wherein,Representing fuzzy satisfaction,/>And (3) representing standardized satisfaction values of all schemes, wherein m represents an optimized number target, and the scheme with the maximum standardized satisfaction has good compatibility with all targets.

Preferably, the external excitation includes unbalanced magnetic tension, sealing excitation force, hydraulic imbalance, oil film force, runner vortex belt eccentric force, rotor bow-like rotation, axial water thrust and generator axial force.

Specifically, the specific formula of the unbalanced magnetic tension force is as follows:

wherein, Representing unbalanced magnetic tension,/>Represents a general coefficient (range 0.2 to 0.5), D represents a generator rotor diameter, L represents a generator rotor height, B represents magnetic induction density,/>Indicating the work angle.

Specifically, the specific formula of the sealing excitation force is as follows:

wherein K represents the equivalent stiffness of the sealing exciting force, Representing the mass of the sealing excitation force,/>Displacement disturbance function representing sealing exciting force,/>Damping indicative of sealing excitation force,/>Representing displacement speed and acceleration of the wheel in x-direction and y-direction,/>Indicating the rotational angular velocity.

Wherein,Represents the equivalent stiffness initial value of the sealing exciting force,/>Represents the damping initial value of the sealing exciting force,Representing the initial value of displacement of the sealing exciting force,/>The expression constant has no specific meaning, j is (j ranges 1/2-3),/>Representing the relative mass eccentricity of the turbine runner,/>，/>Indicating a sealing gap.

Specifically, the specific formula of the hydraulic imbalance is as follows:

wherein, Represents the disturbance coefficient, Q represents the flow,/>Represents the water density, A represents the cross-sectional area of the middle part of the rotating wheel），/>Representing the radius of the water inlet of the rotating wheel,/>Represents the radius of the water outlet of the lower ring,/>Representing the water density,/>Respectively represent the flow rate of the water inlet of the runner blade (/ >)) And the flow velocity at the water outlet of the lower ring），/>Respectively represent inflow angle and outflow angle,/>Representing dynamic eccentricity of wheel,/>Indicating the wheel rotational phase angle.

Specifically, the specific formula of the oil film force is as follows:

wherein, Representing oil film stiffness,/>Indicating the oil film damping coefficient.

Specifically, the specific formula of the eccentric force of the turbine wheel scroll band is as follows:

wherein, The lower ring radius of the runner outlet is represented, Q represents the flow, F represents the cross-sectional area of the runner outlet water [ (]），/>Representing guide vane height,/>Representing rotational speed,/>Mathematical operator tangent calculation/>Indicating the rotor blade mounting angle.

Specifically, the rotational frequency of the vortex strip at the inlet of the draft tube:

wherein, Represent the circumferential velocity at the midpoint of the blade outlet edge,/>Circumferential component representing absolute velocity at the exit of the wheel,/>Represents the radius of the midpoint of the water outlet edge of the blade,/>Representing the radius of the lower ring of the outlet of the rotating wheel,/>The rotating speed is represented, Q represents the flow, F represents the water cross-sectional area of the outlet of the rotating wheel,/>Indicating the rotor blade mounting angle.

Wherein,Representing the water density,/>Represent the circumferential velocity at the midpoint of the blade outlet edge,/>Represents the radius of the midpoint of the water outlet edge of the blade,/>Indicating the eccentricity of the vortex belt of the rotating wheel (under rated working condition/>)) P represents the eccentric vortex band pressure, and the specific formula is as follows:

wherein, Representing the eccentricity of the vortex band of the runner,/>Represents the rotational phase angle of the wheel, t represents time,/>Represents the radius of the midpoint of the water outlet edge of the blade,/>Indicating the rotational frequency of the vortex shedding at the inlet of the draft tube.

Specifically, the arcuate rotor spin includes the arcuate spin centrifugal force of the generator rotorAnd the bow-shaped rotary centrifugal force of the rotating wheel of the water turbine/>The specific formula is as follows:

/>

wherein, Representing moment of inertia,/>Representing equivalent concentrated quality,/>Representing eccentricity,/>The rotation angle is indicated and,Representing rotational angular velocity,/>Representing gravitational acceleration,/>Indicating the rotational angular velocity.

Specifically, the specific formula of the axial water thrust is as follows:

wherein, Represents axial water thrust,/>Representing the coefficient of uncertainty,/>The diameter of the turbine runner is represented, Q represents runner flow, and H represents the water head under actual working conditions.

Specifically, the specific formula of the generator axial force is as follows:

wherein, Representing the equivalent mass of the generator and the main shaft,/>Represents axial water thrust,/>Indicating the gravitational acceleration.

Further, the NSGA-III optimization algorithm flow is specifically as follows: setting NSGA-III parameters, and inputting a plurality of optimized objective functions, the load duty ratio of each unit and the value range of the speed regulator parameters; generating a reference point and calculating a multi-target fitness value of each individual in the population; generating a child population through selection, crossing and mutation, and combining the parent population and the child population to obtain a new population; non-dominant ranking of the pooled populations and selecting individuals to enter the next generation based on a selection operation of reference points; repeating the steps until the maximum iteration times are reached, and outputting each optimal control scheme and a corresponding target fitness value thereof.

In a second aspect, the embodiment of the invention provides an intelligent internet of things gateway method supporting edge computing deployment, which comprises a mathematical model module, a speed regulation system mathematical model for one-pipe multi-machine grid-connected operation of a hydropower station, a hydroelectric generating set shafting multidimensional vibration nonlinear mathematical model and a hydropower station one-pipe multi-machine grid-connected operation nonlinear mathematical model taking shafting-speed regulation coupling into consideration; the control optimization module is used for establishing a multi-objective optimization function so as to reduce the frequency of each unit, the multidimensional vibration of a shafting, the water level of a pressure regulating chamber and the overshoot of the frequency response of a power grid as far as possible and minimize the adjustment time; and the simulation analysis module is used for carrying out simulation analysis of dynamic response characteristics on the typical control scheme with the highest standardized satisfaction and the lowest standardized satisfaction and providing decision support for optimal control of each unit.

The embodiment also provides a computer device, which is suitable for the situation of a method for coordinated optimization control of one-pipe multi-machine grid connection and multiple targets of a hydropower station, and comprises the following steps: a memory and a processor; the memory is used for storing computer executable instructions, and the processor is used for executing the computer executable instructions to realize the method for the one-pipe multi-machine grid-connected multi-target coordination optimization control of the hydropower station according to the embodiment.

The computer device may be a terminal comprising a processor, a memory, a communication interface, a display screen and input means connected by a system bus. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The communication interface of the computer device is used for carrying out wired or wireless communication with an external terminal, and the wireless mode can be realized through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer equipment can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer equipment can be a touch layer covered on the display screen, can also be keys, a track ball or a touch pad arranged on the shell of the computer equipment, and can also be an external keyboard, a touch pad or a mouse and the like.

The embodiment also provides a storage medium, on which a computer program is stored, which when executed by a processor, implements the method for implementing the one-pipe multi-machine grid-connected multi-target coordinated optimization control of the hydropower station as set forth in the above embodiment.

In conclusion, a nonlinear mathematical model of the hydropower station one-pipe multi-machine grid-connected operation taking shafting-speed regulation coupling into consideration is established, so that a model and a theoretical basis are laid for safe and stable regulation and optimization operation of the hydropower station common-pipe multi-machine grid-connected operation; the hydropower station one-pipe multi-machine grid-connected operation multi-target coordination control optimization method provided by the invention considers the coordination distribution of loads among all units, and simultaneously considers the dynamic performance of the shafting of the units in the adjustment process, so that the dynamic adjustment performance of the frequencies of all units, a voltage regulating room and a power grid is integrally improved, and technical support is provided for safe and stable operation of the hydropower units and the power grid.

Example 2

Referring to fig. 1 to 15, in order to verify the beneficial effects of the present invention, a scientific demonstration is performed through economic benefit calculation and simulation experiments, which is a second embodiment of the present invention, and the embodiment provides an intelligent internet of things gateway system supporting edge calculation deployment.

Specifically, a nonlinear mathematical model is established according to fig. 2,3 and 4, and the coupling relation between the shafting and the speed regulating system of the unit is considered. The model is used for describing a grid-connected operation process of one-hole double machines of the hydropower station.

In FIG. 4, the following is illustrativeRespectively comprises a generator rotor, a turbine runner, an upper guide bearing, a lower guide bearing, a centroid coordinate of the water guide bearing, equivalent concentrated mass and a geometric center,The radial swing degrees of the generator rotor, the turbine runner, the upper guide bearing, the lower guide bearing and the water guide bearing are respectively. Wherein/>。

Further, the minimum overshoot and the minimum adjustment time of the multidimensional vibration response of each unit frequency and the shafting are taken as target optimization functions:

wherein, Represents the controller proportional gain of unit i,/>Representing the controller integral gain of unit i,/>Indicating the duty cycle of each unit.

Meanwhile, an optimization objective function considering the minimum water level overshoot and the shortest adjustment time of the power grid and the pressure regulating chamber is established:

wherein, Represents the controller proportional gain of unit i,/>Representing the controller integral gain of the unit i,Representing the integral of the absolute error of the grid frequency with time,/>Representing absolute error of water level of pressure regulating chamber and time integral,/>Indicating the duty cycle of each unit.

The range of values of the decision variables in the optimization objective function is as follows,

。

Further, the NSGA-III population is set to be 30, the iteration number is set to be 50, according to a non-linear mathematical model, a multi-objective optimization function and decision variables thereof, and a NSGA-III multi-objective optimization algorithm flow of one-hole double-machine grid-connected operation of a hydropower station taking into consideration unit shafting-speed regulation coupling, according to parameters of units in tables 1, 2-1 and 2-2 (the table 2-2 is a continuous table of the table 2-1) (note that the unit numbers are omitted from the same parts of the unit parameters in the table), 30 optimization control schemes are obtained in Matlab in an optimization mode, as shown in fig. 6.

Table 11, 2# machine set grid-connected speed regulation system parameter

Table 2-1 1, 2# unit shafting parameters

Table 2-2 1, 2# unit shafting parameters

Further, according to the fuzzy satisfaction decision method, the normalized satisfaction of each scheme is calculated, as shown in fig. 7.

Further, according to the standardized satisfaction evaluation result, the two control schemes with the highest standardized satisfaction and the lowest standardized satisfaction are selected (table 3), the load disturbance dynamic characteristics of the two control schemes are simulated and analyzed in Matlab according to a non-linear mathematical model of the hydropower station one-hole double-machine grid-connected operation taking into consideration the shafting-speed regulation coupling of the unit, the results are shown in fig. 8-15, the water level, the power grid frequency, the 1# unit frequency and the unit vibration radius dynamic characteristics of the scheme 17 are obviously superior to those of the scheme 1 and the 2# unit frequency stability deviation is smaller than that of the scheme 1, and the results show that the proposed control model and method are effective, and the unit regulation control quality can be effectively improved.

TABLE 3 exemplary control scheme

In fig. 12 to 15, the upper light gray is scheme 17, and the lower dark gray is scheme 1.

It should be noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present invention may be modified or substituted without departing from the spirit and scope of the technical solution of the present invention, which is intended to be covered in the scope of the claims of the present invention.

Claims

1. A hydropower station one-pipe multi-machine grid-connection multi-target coordination optimization control method is characterized by comprising the following steps of: comprising the steps of (a) a step of,

Establishing a speed regulation system mathematical model of hydropower station one-pipe multi-machine topological arrangement grid-connected operation, and establishing a unit shafting multidimensional vibration nonlinear mathematical model based on a Lagrange equation;

Coupling the shafting multidimensional vibration nonlinear mathematical model to a grid-connected operation speed regulation system mathematical model to construct a one-pipe-multimachine grid-connected operation nonlinear mathematical model coupling shafting multidimensional vibration of the unit;

Establishing a multi-objective optimization function considering the adjustment performance of a speed regulation system and the multi-dimensional vibration dynamic performance of a shafting, and selecting disturbance load distribution coefficients and speed regulator control parameters of each unit as optimized decision variables;

Optimizing the decision variable by using an NSGA-III multi-objective optimization algorithm to obtain various pareto control schemes meeting the requirements;

evaluating and analyzing all the control schemes by using a fuzzy satisfaction evaluation method, and selecting a scheme with highest standardized satisfaction as a final coordinated optimization control scheme;

Dynamically adjusting response characteristics of the unit of the highest standardized satisfaction scheme and the lowest standardized satisfaction scheme through simulation contrast analysis so as to verify the effectiveness of the proposed coordination control strategy;

The method for establishing the mathematical model of the speed regulation system for the one-pipe multi-machine topological arrangement grid-connected operation of the hydropower station comprises the following steps:

Establishing a subsystem mathematical model, wherein the subsystem mathematical model comprises a diversion tunnel equation, a pressure regulating chamber continuity equation, a common pipe pressure pipeline equation, a branch pipe flow continuity equation, a branch pipe pressure pipeline equation of each unit, a hydraulic turbine moment flow equation of each unit, a generator equation of each unit, a speed regulator equation of each unit and a power grid equivalent equation;

according to the physical connection and operation characteristics among all subsystems, all subsystem mathematical models are combined to construct an integral hydropower station one-pipe multi-machine grid-connected operation speed regulation system mathematical model;

the specific formula of the mathematical model of the hydropower station one-pipe multi-machine grid-connected operation speed regulation system is as follows:

wherein, Representing the inertial time constant of water flow of diversion tunnel,/>Representing head loss of diversion tunnel,/>Representing the rated head,/>Representing the relative value of flow deviation of diversion tunnel,/>Representing the flow deviation relative value of branch pipes of each unit,/>Representing inertial time constant of each unit,/>Representing the time constant of the pressure regulating chamber,/>Representing the inertial time constant of the water flow of the common pressure pipeline,Representing the inertia time constant of water flow of each branch pipe,/>Representing the equivalent load self-regulating coefficient of the power grid,/>Representing the time constant of the equivalent servomotor of the power grid,/>Representing the equivalent inertial time constant of the power grid,/>Representing the equivalent permanent state slip coefficient of the power grid,/>Representing pressure line loss,/>Representing the head loss of branch pipes of each unit,/>Respectively representing the deviation relative values of the rotating speed, the opening degree of the guide vane, the power moment of the water turbine and the resistance moment of the generator of each unitRepresenting the moment transfer coefficient of each water turbine,/>Representing the flow transfer coefficient of each water turbine,/>Indicating the response time constant of each servomotor,Respectively representing the proportional gain and the integral gain of each speed regulator,/>Representing the load self-regulating coefficient of each generator,/>Representing the equivalent synchronous coefficient of each generator,/>Representing the relative value of flow deviation of a shared pipeline,/>The power angle of each generator is represented,Representing the equivalent damping coefficient of each generator,/>Representing the relative value of the frequency deviation of the power grid,/>Representing intermediate variables,/>The method comprises the steps of representing disturbance load of a power grid, i representing a unit number, B representing the ratio of hydroelectric unit power in the power grid, n representing the number of branch pipes, t representing time, and z representing the relative value of water level deviation of a pressure regulating chamber;

the establishment of the nonlinear mathematical model of the multi-dimensional vibration of the unit shafting comprises the following steps:

According to the shafting structure of the hydroelectric generating set, the geometric position relation among the rotor, the rotating wheel and the guide bearing is established, and the specific formula is as follows:

wherein, Representing shafting dimension parameter,/>Respectively representing the vibration radius of a generator rotor, a turbine runner, an upper guide bearing, a lower guide bearing and a water guide bearing;

the method comprises the steps of establishing a multidimensional vibration kinetic energy equation T of a hydro-generator set shafting, wherein the specific equation is as follows:

wherein, Representing the centroid coordinates of the generator rotor,/>Representing the barycentric coordinates of the turbine runner,/>Respectively represent the rotational inertia of the generator rotor and the turbine runner,/>Respectively represent the concentrated mass of the generator rotor and the turbine runner,/>Respectively representing the eccentricity of the rotor of the generator and the runner of the water turbine,/>Respectively representing the rotation angles of the generator rotor and the turbine runner,/>Respectively represent the equivalent mass of the generator rotor and the turbine runner,/>Respectively representing the vibration speeds of the generator rotor and the turbine runner,/>Respectively representing rotational angular velocities of the generator rotor and the runner;

the method comprises the steps of establishing a multi-dimensional vibration potential energy equation U of a unit shafting, wherein the specific formula is as follows:

wherein, Representing the centroid coordinates of the generator rotor,/>Representing the barycentric coordinates of the turbine runner,/>Respectively representing the rotation angles of the generator rotor and the turbine runner,/>Respectively represent the equivalent mass of the generator rotor and the turbine runner,/>Representing gravitational acceleration,/>Representing axial stiffness,/>Representing thrust guide bearing stiffness,/>Expressed as axle torsional stiffness,/>Representing the equivalent rigidity of the shafting;

Adding damping force as a linear factor into a rotor of a generator and a runner of a water turbine, and simultaneously considering various external force excitations of the rotor and the runner;

substituting the kinetic energy equation T, the potential energy equation U and external force excitation into a Lagrangian equation to deduce a shafting multidimensional vibration nonlinear mathematical model of the hydroelectric generating set;

Wherein i represents the number of the unit, Respectively represent unbalanced magnetic tension in x and y directions of generator rotor with unit number of i,/>, andRespectively representing the bow-shaped rotary force of the generator rotor with the unit number i in the x and y directions,The oil film forces of the upper guide bearings in the x and y directions of the generator rotor with the unit number i are respectively shown,Oil film force of down-guide bearing of generator rotor with unit number i in x and y directions is expressed respectively,/>Representing the axial resultant force of unit number i,/>Sealing exciting forces in x and y directions of turbine runner with unit number i are respectively expressed, and the sealing exciting forces are expressed by/>Respectively represents hydraulic unbalance force of the turbine runner with the unit number i in the x and y directions,Vortex belt eccentric force in x and y directions of turbine runner with unit number i is expressed respectively,/>Respectively representing bow-shaped turning force in x and y directions of turbine runner with unit number i,/>The oil film force of the water guide bearing in the x and y directions of the turbine runner with the unit number i is respectively expressed, and the oil film force is/Represents the axial water thrust of the unit number i,/>Respectively representing the mass of a generator rotor and a turbine runner with the unit number of i,/>Represents the equivalent concentrated mass of the generator rotor with the unit number i and the rotating shaft thereof, the turbine runner and the rotating shaft thereof,Respectively representing the mass center coordinates of a generator rotor and a turbine runner with the unit number of i,/>Respectively representing the rotation angles of the generator rotor with the unit number of i and the turbine runner,Respectively represents the equivalent rigidity of shafting with unit number i,/>Respectively representing the eccentricity of the generator rotor with the unit number i and the turbine runner,/>Represents the axial stiffness of the unit number i,/>Represents the rigidity of a thrust guide bearing with the unit number of i,/>Represents the torsional stiffness of the shaft with the unit number i,/>Respectively representing the rotational inertia of a generator rotor with the unit number of i and the rotational inertia of a turbine runner of a water turbineRespectively representing the moment of the generator rotor and the turbine runner with the unit number of i,/>Damping coefficient of generator rotor and turbine runner respectively representing unit number i,/>Indicating the torsion angle of the unit number i,/>Respectively representing the vibration speeds of the generator rotor with the unit number of i and the turbine runner,Vibration acceleration of generator rotor and turbine runner respectively indicated by unit number i,/>Respectively representing the rotation angular velocity of the generator rotor with the unit number of i and the turbine runner,The rotational angular accelerations of a generator rotor and a turbine runner with unit numbers i are respectively represented;

The one-pipe multi-machine grid-connected operation nonlinear mathematical model comprises the following steps:

The method comprises the following steps of establishing a unit rotation equation considering unit shafting-speed regulation coupling, wherein the specific formula is as follows:

wherein, Representing the inertial time constant of water flow of diversion tunnel,/>Representing head loss of diversion tunnel,/>Representing the rated head,/>Representing the relative value of flow deviation of diversion tunnel,/>Representing the flow deviation relative value of branch pipes of each unit,/>Representing inertial time constant of each unit,/>Representing the time constant of the pressure regulating chamber,/>Representing the inertial time constant of the water flow of the common pressure pipeline,Representing the inertia time constant of water flow of each branch pipe,/>Representing the equivalent load self-regulating coefficient of the power grid,/>Representing the time constant of the equivalent servomotor of the power grid,/>Representing the equivalent inertial time constant of the power grid,/>Representing the equivalent permanent state slip coefficient of the power grid,/>Representing pressure line loss,/>Representing the head loss of branch pipes of each unit,/>Respectively representing the relative values of the rotating speed of each unit, the opening degree of the guide vane, the power moment of the water turbine and the resistance moment deviation of the generator,/>Representing the moment transfer coefficient of each water turbine,/>Representing the flow transfer coefficient of each water turbine,/>Indicating the response time constant of each servomotor,Respectively representing the proportional gain and the integral gain of each speed regulator,/>Representing the load self-regulating coefficient of each generator,/>Representing the equivalent synchronous coefficient of each generator,/>Representing the relative value of flow deviation of a shared pipeline,/>The power angle of each generator is represented,Representing the equivalent damping coefficient of each generator,/>Representing the relative value of the frequency deviation of the power grid,/>Meaning intermediate variables are of no particular significance,/>The method is characterized in that the method comprises the steps of representing disturbance load of a power grid, i representing a unit number, B representing the ratio of hydroelectric unit power in the power grid, n representing the number of branch pipes, t representing time, z representing the relative value of water level deviation of a pressure regulating chamber, and/(o)Respectively represent unbalanced magnetic tension in x and y directions of generator rotor with unit number of i,/>, andArcuate turning forces in x and y directions of generator rotor with unit number i are respectively expressed, iOil film force of upper guide bearing of generator rotor in x and y directions with unit number i is expressed respectively,/>The oil film forces of the down guide bearings in the x and y directions of the generator rotor with the unit number i are respectively shown,Representing the axial resultant force of unit number i,/>Sealing exciting forces in x and y directions of turbine runner with unit number i are respectively expressed, and the sealing exciting forces are expressed by/>Respectively representing hydraulic unbalance force in x and y directions of turbine runner with unit number i,/>Vortex belt eccentric force in x and y directions of turbine runner with unit number i is expressed respectively,/>Respectively representing bow-shaped turning force in x and y directions of turbine runner with unit number i,/>The oil film force of the water guide bearing in the x and y directions of the turbine runner with the unit number i is respectively expressed, and the oil film force is/Represents the axial water thrust of the unit number i,/>Respectively representing the mass of a generator rotor and a turbine runner with the unit number of i,/>Represents the equivalent concentrated mass of the generator rotor with the unit number i and the rotating shaft thereof, the turbine runner and the rotating shaft thereof,Respectively representing the mass center coordinates of a generator rotor and a turbine runner with the unit number of i,/>Respectively representing the rotation angles of the generator rotor with the unit number of i and the turbine runner,Respectively represents the equivalent rigidity of shafting with unit number i,/>Respectively representing the eccentricity of the generator rotor with the unit number i and the turbine runner,/>Represents the axial stiffness of the unit number i,/>Represents the rigidity of a thrust guide bearing with the unit number of i,/>Represents the torsional stiffness of the shaft with the unit number i,/>Respectively representing the rotational inertia of a generator rotor with the unit number of i and the rotational inertia of a turbine runner of a water turbineRespectively representing the moment of the generator rotor and the turbine runner with the unit number of i,/>Damping coefficient of generator rotor and turbine runner respectively representing unit number i,/>Indicating the torsion angle of the unit number i,/>Respectively representing the vibration speeds of a generator rotor and a turbine runner with unit numbers of i,/>Vibration acceleration of generator rotor and turbine runner respectively indicated by unit number i,/>Respectively representing the rotation angular velocity of a generator rotor and a turbine runner with unit number i,/>The rotational angular accelerations of the generator rotor and the turbine runner are respectively indicated by the unit number i.

2. The hydropower station one-pipe-multiple-machine grid-connected multi-target coordination optimization control method as claimed in claim 1, wherein the method comprises the following steps: the establishment of the multi-objective optimization function considering the regulation performance of the speed regulation system and the multi-dimensional vibration dynamic performance of the shafting comprises the following principles:

Taking the integral of the absolute error and time as the minimum overshoot and the minimum adjustment time performance evaluation of the dynamic response output of each system, and the specific formula is as follows:

Wherein t represents time;

wherein, Represents the controller proportional gain of unit i,/>Representing the controller integral gain of unit i,/>Representing the integral of the absolute error of the frequency of the unit i with time,/>Respectively representing the integral of the absolute error of the vibration radius of the unit i shafting rotor and the rotating wheel and the time,/>Representing the duty ratio of each unit,/>The weight of each index is represented by the weight of each index,Each unit dynamic response target 1 is represented, and i represents a unit number;

wherein/> Represents the controller proportional gain of unit i,/>Representing the controller integral gain of unit i,/>Representing the load duty ratio of the unit i,/>Representing the dynamic response objective 2,/>, of the systemRepresenting the integral of the absolute error of the grid frequency with time,/>Indicating the absolute error of the pressure regulating chamber water level and the time integral.

3. The hydropower station one-pipe-multiple-machine grid-connected multi-target coordination optimization control method as claimed in claim 1, wherein the method comprises the following steps: the method for optimizing the decision variable by using the NSGA-III multi-objective optimization algorithm comprises the following steps:

Setting NSGA-III parameters, and inputting a plurality of optimized objective functions, the load duty ratio of each unit and the value range of the speed regulator parameters;

generating a reference point and calculating a multi-target fitness value of each individual in the population;

Generating a child population through selection, crossing and mutation, and combining the parent population and the child population to obtain a new population;

Non-dominant ranking of the pooled populations and selecting individuals to enter the next generation based on a selection operation of reference points;

repeating the steps until the maximum iteration times are reached, and outputting each optimal control scheme and the corresponding target fitness value.

4. The hydropower station one-pipe-multiple-machine grid-connected multi-target coordination optimization control method as claimed in claim 1, wherein the method comprises the following steps: the fuzzy satisfaction evaluation method comprises the following steps:

according to the fitness value of each target, a fuzzy membership function is selected, and fuzzy satisfaction is calculated, wherein the specific formula is as follows:

wherein, Representing i target,/>Representing the maximum fitness value,/>Representing a minimum fitness value, j representing the number of non-inferior solutions;

and calculating the standardized satisfaction degree of each scheme according to the fuzzy satisfaction degree, wherein the specific formula is as follows:

wherein, Representing fuzzy satisfaction,/>Representing standardized satisfaction values of all schemes, wherein m represents an optimized number target;

5. The hydropower station one-pipe-multi-machine-grid-connection multi-target coordination optimization control system is based on the hydropower station one-pipe-multi-machine-grid-connection multi-target coordination optimization control method according to any one of claims 1-4, and is characterized in that: also included is a method of manufacturing a semiconductor device,

The mathematical model module is used for constructing a mathematical model of a hydropower station one-pipe multi-machine grid-connected operation speed regulation system, a shafting multidimensional vibration nonlinear mathematical model of a hydroelectric generating set and a hydropower station one-pipe multi-machine grid-connected operation nonlinear mathematical model taking shafting-speed regulation coupling into consideration;

the control optimization module is used for establishing a multi-objective optimization function so as to reduce the frequency of each unit, the multidimensional vibration of a shafting, the water level of a pressure regulating chamber and the overshoot of the frequency response of a power grid as far as possible and minimize the adjustment time;

and the simulation analysis module is used for carrying out simulation analysis of dynamic response characteristics on the typical control scheme with the highest standardized satisfaction and the lowest standardized satisfaction and providing decision support for optimal control of each unit.

6. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that: the method for achieving the one-pipe multi-machine grid-connection multi-target coordination optimization control of the hydropower station according to any one of claims 1-4 is implemented when the processor executes the computer program.

7. A computer-readable storage medium having stored thereon a computer program, characterized by: the method for achieving the one-pipe multi-machine grid-connection multi-target coordination optimization control of the hydropower station according to any one of claims 1-4 when the computer program is executed by a processor.