CN117134418B - Load flow calculation method, device and equipment of multi-energy coupling system - Google Patents
Load flow calculation method, device and equipment of multi-energy coupling system Download PDFInfo
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D5/00—Protection or supervision of installations
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D19/00—Details
- F24D19/10—Arrangement or mounting of control or safety devices
- F24D19/1006—Arrangement or mounting of control or safety devices for water heating systems
- F24D19/1009—Arrangement or mounting of control or safety devices for water heating systems for central heating
- F24D19/1048—Counting of energy consumption
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- H02J2203/00—Indexing scheme relating to details of circuit arrangements for AC mains or AC distribution networks
- H02J2203/10—Power transmission or distribution systems management focussing at grid-level, e.g. load flow analysis, node profile computation, meshed network optimisation, active network management or spinning reserve management
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- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
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Abstract
The invention provides a tide computing method, a tide computing device and tide computing equipment of a multi-energy coupling system, and relates to the technical field of energy management, wherein the tide computing method comprises the following steps: constructing a natural gas network model, a heating network model, an electric power network model and a coupling equipment model; obtaining a steady-state model of the multi-energy coupling system according to the natural gas network model, the heat supply network model, the electric power network model and the coupling equipment model; obtaining a nonlinear algebraic equation of the multi-energy coupling system according to a steady-state model of the multi-energy coupling system; according to a nonlinear algebraic equation and a continuous Newton method, a five-order precision solution and a four-order precision solution of the multi-energy coupling system are obtained; and obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution. The flow calculation precision is improved through the participation of multiple models, meanwhile, the convergence of the flow calculation of the multi-energy coupling system is improved through the continuous Newton method, the operation speed is improved, and accurate references are provided for planning, reliability evaluation, operation scheduling and the like of the multi-energy coupling system.
Description
Technical Field
The invention relates to the technical field of energy management, in particular to a tide computing method, a tide computing device and tide computing equipment of a multi-energy coupling system.
Background
To cope with increasingly severe climatic problems, conventional rough and inefficient energy systems are gradually transformed into efficient and clean directions. The coupling complementary relation of multiple energy sources such as electricity, gas, heat and the like is generally utilized, and the joint operation regulation and control of the multiple energy source systems are realized through an energy co-production and conversion technology, so that the overall economy and operation efficiency of the energy source systems are improved. However, similarly, because of the mutually restricted physical mechanism among heterogeneous energy sources, the multi-energy system also presents an operation rule different from that of a single subsystem, so that the analysis means of the original mature electric/gas/heat independent system is disabled, and therefore, the distribution of important state quantities such as voltage, power, temperature and pressure is obtained by solving a steady-state model equation of the multi-energy system, and the trend calculation can provide important reference evidence for the researches such as safe operation, reliability assessment and operation scheduling of the multi-energy coupling system.
In the prior art, due to the difference of the coupling energy sources, the multi-energy coupling system cannot analogize each coupling energy source according to the same per unit model, so that the multi-energy coupling system cannot accurately calculate the power flow. For example, a multi-energy coupling system involves coupling of multiple energy sources such as electricity, gas and heat, but the gas-heat system does not have a per-unit model, so it is difficult to analogize that an electric power system takes a variable per-unit value as an initial value of each state quantity of the gas-heat system, and the gas-heat system is a directed network, and particularly when a non-radial system is considered, it is difficult to judge the flow direction of a heating medium such as gas in each pipeline through priori knowledge.
Disclosure of Invention
The invention solves the technical problem of how to improve the efficiency and the accuracy of the load flow calculation of the multi-energy coupling system.
The invention provides a tide calculation method of a multi-energy coupling system, which comprises the following steps:
constructing a natural gas network model, a heating network model, an electric power network model and a coupling equipment model;
obtaining a steady-state model of the multi-energy coupling system according to the natural gas network model, the heating network model, the electric power network model and the coupling equipment model;
obtaining a nonlinear algebraic equation of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system;
according to the nonlinear algebraic equation and the continuous Newton method, a fifth-order precision solution and a fourth-order precision solution of the multi-energy coupling system are obtained;
and obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution.
Optionally, the building of the natural gas network model, the heating network model, the electric power network model and the coupling equipment model includes:
obtaining the natural gas network model according to an airflow equation, a node mass flow conservation equation and a compressor model;
the airflow equation is:
；
Wherein,for the node of the multi-energy coupling system +.>And node->The gas flow in the pipeline between the two;Is a pipeline coefficient;For the node->Is a pressure of (1);For the node->Is a pressure of (1);Is a sign function, which satisfies +.>；Is the length of the pipe;Is the diameter of the pipe;A coefficient of friction for the pipe;Is the gas temperature;Is the gas compression coefficient;Is natural gas relative density;
the node mass flow conservation equation is:
；
wherein,for node->Is>For the pipeline->Is a gas mass flow of>For flowing into the node->Is a set of pipes;
the compressor model is as follows:
；
wherein,compression ratio of the compressor for the multi-energy coupling system, +.>For the pressure at the high-pressure side of the compressor, +.>Is the pressure on the low pressure side of the compressor.
Optionally, the building of the natural gas network model, the heating network model, the electric power network model and the coupling equipment model further comprises:
obtaining the heating network model according to the hydraulic model and the thermodynamic model;
the thermodynamic model comprises a pipeline temperature transmission equation, a node temperature mixing equation and a node heat exchange equation, and the hydraulic model comprises a node mass flow continuous equation and a head loss equation;
Wherein, pipeline temperature transmission equation is:
；
wherein,for the inlet temperature of the pipe, +.>For the outlet temperature of the pipe, +.>In order to be at the temperature of the environment,is the specific heat capacity of water->For the mass flow of the pipe, +.>For the thermal coefficient of the pipe, +.>Is the length of the pipeline;
the node temperature mixing equation is:
；
；
wherein,for the node->Temperature of>For the pipeline->Mass flow of>For the pipeline->Is>For the pipeline->Is>For the node flowing into the pipeline +.>Pipe set of>For the node out of the pipe +.>Is a set of pipes;
the node heat exchange equation is as follows:
；
wherein,thermal power generated/consumed for said node, < >>Supplying water to the nodes with temperature->The temperature of the return water of the node;
the mass flow continuous equation of the node is as follows:
；
wherein,for node->Is/are/is/are>Is a pipeline->Mass flow of>For flowing into the node->Is a set of pipes;
the head loss equation is:
；
wherein,for the pressure drop coefficient of the pipe, +.>For the pipeline->Mass flow of>For loops->Is provided.
Optionally, the building of the natural gas network model, the heating network model, the electric power network model and the coupling equipment model includes:
Obtaining the power network model according to a node power injection equation and a node voltage equation;
the node power injection equation is:
；
；
wherein,for the node->Is +.>For the node->Is filled with reactive power, ">For the node->Voltage amplitude of>For the node->Voltage amplitude of>For the node->And said node->The real part of the admittance between +.>For the node->And->An imaginary part of the admittance therebetween;For the node->And said node->A voltage phase angle difference therebetween;
the node voltage equation is:
；
；
wherein,for the node->Voltage amplitude of>For a given value of the voltage amplitude, +.>To balance the voltage phase angle of the node +.>For a given value of the voltage phase angle, +.>Is a set of supply voltages and the balancing node.
Optionally, the building of the natural gas network model, the heating network model, the electric power network model and the coupling equipment model further comprises:
obtaining the coupling equipment model according to a gas turbine model, a boiler model, a cogeneration unit model and a circulating pump model;
the gas turbine model is as follows:
；
wherein,for the natural gas flow consumed by the gas turbine, < > for the gas turbine >，And->For the energy consumption coefficient of the gas turbine, < >>Is the net calorific value of natural gas, +.>Output electrical power for the gas turbine;
the boiler model is as follows:
；
wherein,for the natural gas flow consumed by the boiler, +.>For the thermal power output by the boiler, +.>For the power conversion efficiency of the boiler, +.>Is the net heating value of the natural gas;
the cogeneration unit model is as follows:
；
wherein,for the natural gas flow consumed by the cogeneration unit, +.>Is the net calorific value of natural gas, +.>For the heat output of the cogeneration unit, < >>Electric power output for the cogeneration unit, < >>Power conversion efficiency for the cogeneration unit;
the circulating pump model is as follows:
；
wherein,for the consumed electrical power of the circulation pump, +.>For the inlet mass flow of the circulation pump, < > is>Acceleration of gravity, ++>Is water head pressure>Is the circulation pump efficiency.
Optionally, the obtaining a nonlinear algebraic equation of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system includes:
obtaining related variables of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system;
obtaining the nonlinear algebraic equation according to the related variables;
The nonlinear algebraic equation is:；
wherein,，as the related variables, the related variables include the temperature, flow, power, and voltage of the multi-energy coupling system.
Optionally, the obtaining a fifth-order precision solution and a fourth-order precision solution of the multi-energy coupling system according to the nonlinear algebraic equation and the continuous newton method includes:
obtaining a nonlinear function according to the nonlinear algebraic equation;
the nonlinear function is:；
according to the nonlinear function, obtaining the five-order precision solution and the four-order precision solution of the multi-energy coupling system through the continuous Newton method;
the fifth-order precision solution is as follows:
；
wherein,for the five-order precision solution, +.>Is an intermediate variable +.>，Is a coefficient of->Is->Solution of multiple iterations,/->Is an iteration step length;
the fourth-order precision solution is:
；
wherein,for the fourth order precision solution, +.>Is->Solution of multiple iterations,/->For the iteration step +.>Is a coefficient of->Is the intermediate variable.
Optionally, the obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution includes:
adjusting the iteration step according to the difference value of the fifth-order precision solution and the fourth-order precision solution;
Obtaining the tide of the multi-energy coupling system through the iteration step length;
the step of adjusting the iteration step according to the difference value between the fifth-order precision solution and the fourth-order precision solution comprises the steps of:
normalizing the difference value of the fifth-order precision solution and the fourth-order precision solution to obtain a tide calculation error expression of the multi-energy coupling system:
；
wherein,represents->Norms (F/F)>Is->Solution of multiple iterations,/->For iterative step length +.>A difference value between the five-order precision solution and the four-order precision solution;
when (when)Less than a preset second error limit->When the iteration step length is reduced, the reduced iteration step length is obtained;
the iteration step after the reduction is as follows:
；
wherein,for said iteration step after said decrease, +.>As a minimum value of the iteration step,the iteration step length is the iteration step length;
repeatedly obtaining a five-order precision solution and a four-order precision solution of the multi-energy coupling system according to the nonlinear algebraic equation and the continuous Newton method;
when (when)Is greater than said preset second error limit +.>When the iteration step length is increased, the increased iteration step length is obtained;
the iteration step after the increase is as follows:
；
wherein, For said iteration step after said increase, +.>The iteration step length is the iteration step length;
and when the number of times of increasing the iteration step is larger than the preset number of times, obtaining the tide of the multi-energy coupling system.
The invention also provides a tide computing device of the multi-energy coupling system, which comprises:
the steady-state model building module is used for building a natural gas network model, a heating network model, an electric power network model and a coupling equipment model; obtaining a steady-state model of the multi-energy coupling system according to the natural gas network model, the heating network model, the electric power network model and the coupling equipment model;
the power flow calculation module is used for obtaining a nonlinear algebraic equation of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system; according to the nonlinear algebraic equation and the continuous Newton method, a fifth-order precision solution and a fourth-order precision solution of the multi-energy coupling system are obtained; and obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution.
The invention also provides a computer device comprising a memory, a processor and a computer program stored on the memory and capable of running on the processor, which is characterized in that the processor realizes the load flow calculation method of the multi-energy coupling system when executing the computer program.
According to the power flow calculation method, the device and the equipment of the multi-energy coupling system, a steady-state model is built through the natural gas network model, the heat supply network model, the power network model and the coupling equipment model, the power flow of the multi-energy coupling system is calculated based on the steady-state model by utilizing the continuous Newton method, the integral power flow analysis of the multi-energy coupling system with multiple energy sources such as electricity, gas and heat is realized, the energy systems without per unit model such as a gas-heat system and the like are overcome through multi-model participation calculation, the fact that the power system is difficult to be analogized and takes the per unit value of a variable as the initial value of each state quantity is caused, the power flow calculation precision is improved, meanwhile, the convergence of the power flow calculation of the multi-energy coupling system is improved by utilizing the continuous Newton method, the operation speed is improved, and accurate references are provided for the planning, the reliability evaluation, the operation scheduling and the like of the multi-energy coupling system.
Drawings
FIG. 1 is a flow chart of a method for power flow calculation of a multi-energy coupling system according to an embodiment of the invention;
FIG. 2 is a schematic diagram of a power flow calculation device of a multi-energy coupling system according to another embodiment of the present invention;
fig. 3 is a schematic structural diagram of a computer device according to another embodiment of the present invention.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Referring to fig. 1, the present invention provides a load flow calculation method of a multi-energy coupling system, including:
s1: and constructing a natural gas network model, a heating network model, an electric power network model and a coupling equipment model.
Specifically, before the steady-state model of the multi-energy coupling system is reconstructed, the steady-state model of the multi-energy coupling system needs to include a natural gas network model, a heating network model, an electric power network model and a coupling equipment model, so that the models need to be preferentially constructed, and power flow calculation is conveniently carried out according to a plurality of energy systems of the multi-energy coupling system.
S2: and obtaining a steady-state model of the multi-energy coupling system according to the natural gas network model, the heating network model, the electric power network model and the coupling equipment model.
In particular, the natural gas network model reflects the flow and pressure changes of natural gas in the pipeline network. The natural gas network model may be represented using an airflow equation, a node mass flow conservation equation, and a compressor model. The heating network model reflects the transmission and supply conditions of heat energy in the pipeline network, and can be expressed by using a pipeline temperature transmission equation, a node temperature mixing equation and a node heat exchange equation. The power network model reflects the transmission and supply of electrical energy in the power grid, and can be represented using node power injection equations and node voltage equations. The coupling equipment model reflects coupling equipment (such as a cogeneration device and the like) in the multi-energy coupling system, and the coupling equipment model can be represented by using a gas turbine model, a boiler model, a cogeneration unit model and a circulating pump model. By integrating the models, a steady-state model of the multi-energy coupling system can be established. The mathematical model of each parameter of the multi-energy coupling system in the steady state working state can be obtained by simultaneous solving of the equations of each subsystem.
S3: and obtaining a nonlinear algebraic equation of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system.
Specifically, for each subsystem, its steady state equation is reduced to an equation form, and the equations in all subsystems are combined. And according to the coupling relation of the systems, the variables and the equations of each subsystem are mutually connected to form a large nonlinear equation.
S4: and obtaining a five-order precision solution and a four-order precision solution of the multi-energy coupling system according to the nonlinear algebraic equation and the continuous Newton method.
Specifically, the continuous newton method is an iterative solution method, in which the result of each iteration approximates to the solution of an equation, and the number of iterations and the convergence depend on the complexity of a specific problem and the effectiveness of a numerical algorithm. Therefore, it is necessary to adjust the stop condition of the iteration, i.e., to set an appropriate number of iterations.
S5: and obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution.
Specifically, an iteration method of a five-order precision solution is used for carrying out five continuous Newton iterations, an iteration method of a four-order precision solution is used for carrying out four continuous Newton iterations, and the tide distribution condition of the multi-energy coupling system under the five-order precision and the four-order precision is obtained through the steps. These trend data may be used for further applications in system analysis, performance assessment, security verification, etc.
According to the power flow calculation method of the multi-energy coupling system, a steady-state model is built through the natural gas network model, the heat supply network model, the power network model and the coupling equipment model, the power flow of the multi-energy coupling system is calculated based on the steady-state model by utilizing the continuous Newton method, the integral power flow analysis of the multi-energy coupling system with multiple energy sources coupled by electricity, gas, heat and the like is realized, the energy systems without the per unit model such as the gas-heat system and the like are overcome through multi-model participation calculation, the power flow calculation precision is improved due to the fact that the variable per unit value is used as the initial value of each state quantity by the power system, meanwhile, the convergence of the power flow calculation of the multi-energy coupling system is improved by utilizing the continuous Newton method, the operation speed is improved, and accurate references are provided for planning, reliability assessment, operation scheduling and the like of the multi-energy coupling system.
In the embodiment of the invention, the building of the natural gas network model, the heating network model, the electric power network model and the coupling equipment model comprises the following steps:
obtaining the natural gas network model according to an airflow equation, a node mass flow conservation equation and a compressor model;
the airflow equation is:
；
wherein,for the node of the multi-energy coupling system +. >And node->The gas flow in the pipeline between the two;Is a pipeline coefficient;For the node->Is a pressure of (1);For the node->Is a pressure of (1);Is a sign function, which satisfies +.>；Is the length of the pipe;Is the diameter of the pipe;A coefficient of friction for the pipe;Is the gas temperature;Is the gas compression coefficient;Is natural gas relative density;
the node mass flow conservation equation is:
；
wherein,for node->Is>For the pipeline->Is a gas mass flow of>For flowing into the node->Is a set of pipes;
the compressor model is as follows:
；
wherein,compression ratio of the compressor for the multi-energy coupling system, +.>For the pressure at the high-pressure side of the compressor, +.>Is the pressure on the low pressure side of the compressor.
In this embodiment, the relationship between the gas flow in the pipeline and the pressure at the nodes at two ends of the pipeline needs to be determined by using a gas flow equation, namely:
；
wherein,node of a multifunctional coupling system>And node->The gas flow in the pipeline between the two;Is a pipeline coefficient;For node->Is a pressure of (1);For node->Is a pressure of (1);As a sign function, the sign function satisfies；Is the length of the pipeline; / >Is the diameter of the pipeline;Is the friction coefficient of the pipeline;is the gas temperature;Is the gas compression coefficient;Is natural gas relative density;
the node mass flow conservation equation is:
；
wherein,for node->Is>Is a pipeline->Is a gas mass flow of>For inflow node->Is a set of pipes;
to compensate for the pressure drop of the gas along the pipe to maintain the gas pressure at a reasonable level, the gas is pressurized using a compressor model:
；
wherein,compression ratio of the compressor for the multi-energy coupling system, +.>For the pressure at the high-pressure side of the compressor, +.>A pressure on a low pressure side of the compressor;
if the gas flow in the pipeline where the compressor is located isThe energy consumed by the compressor is +.>The method comprises the following steps:
；
wherein,for the compression factor of the compressor, +.>Is standard pressure +.>For standard temperature, +.>Specific heat of natural gas->Is the gas compression coefficient>For the inlet temperature of the compressor, +.>Is a compression ratio of the compressor;
if the compressor is driven by a gas turbine, the compressor consumes a flow of gasThe method comprises the following steps:
；
wherein,，，for the loss factor of the compressor, +. >Energy consumed for the compressor.
According to the tide calculation method of the multifunctional coupling system, the natural gas network model reflects the flow and pressure change of natural gas in a pipeline network through an airflow equation, a node mass flow conservation equation and a compressor model.
In the embodiment of the invention, the building of the natural gas network model, the heating network model, the electric power network model and the coupling equipment model further comprises:
obtaining the heating network model according to the hydraulic model and the thermodynamic model;
the thermodynamic model comprises a pipeline temperature transmission equation, a node temperature mixing equation and a node heat exchange equation, and the hydraulic model comprises a node mass flow continuous equation and a head loss equation;
wherein, pipeline temperature transmission equation is:
；
wherein,for the inlet temperature of the pipe, +.>For the outlet temperature of the pipe, +.>In order to be at the temperature of the environment,is the specific heat capacity of water->For the mass flow of the pipe, +.>For the thermal coefficient of the pipe, +.>Is the length of the pipeline;
the node temperature mixing equation is:
；
；
wherein,for the node->Temperature of>For the pipeline->Mass flow of>For the pipeline- >Is>For the pipeline->Is>For the node flowing into the pipeline +.>Pipe set of>For the node out of the pipe +.>Is a set of pipes;
the node heat exchange equation is as follows:
；
wherein,thermal power generated/consumed for said node, < >>Supplying water to the nodes with temperature->The temperature of the return water of the node;
the mass flow continuous equation of the node is as follows:
；
wherein,for node->Is/are/is/are>Is a pipeline->Mass flow of>For flowing into the node->Is a set of pipes;
the head loss equation is:
；
wherein,for the pressure drop coefficient of the pipe, +.>For the pipeline->Mass flow of>For loops->Is provided.
In this embodiment, the heating network model includes a thermal model including a pipeline temperature transmission equation, a node temperature mixing equation, and a node heat exchange equation, and a hydraulic model including a node mass flow continuous equation, and a head loss equation.
Wherein, pipeline temperature transmission equation is:
；
wherein,for the inlet temperature of the pipeline, +.>For the outlet temperature of the pipe, +.>For ambient temperature->Is the specific heat capacity of water->For the mass flow of the pipeline, +. >Is the thermal coefficient of the pipeline>Is the length of the pipeline;
the node temperature mixing equation is:
；
；
wherein,for node->Temperature of>Is a pipeline->Mass flow of>Is a pipeline->Is used for the temperature control of the gas turbine,is a pipeline->Inlet temperature of>For the node of the inflow conduit>Pipe set of>For the node of the outflow line>Is a set of pipes;
the node heat exchange equation is:
；
wherein,thermal power generated/consumed for a node, +.>Supplying water to the nodes with temperature->The temperature of the return water of the node;
the mass flow continuous equation of the node is:
；/>
wherein,for node->Is/are/is/are>Is a pipeline->Mass flow of>For inflow node->Is a set of pipes;
the head loss equation is:
；
wherein,for the pressure drop coefficient of the pipeline, +.>Is a pipeline->Mass flow of>For loops->Is a set of pipes in the pipeline.
According to the tide calculation method of the multi-energy coupling system, the heat supply network model reflects the transmission and supply conditions of heat energy in a pipeline network by using a pipeline temperature transmission equation, a node temperature mixing equation and a node heat exchange equation.
In the embodiment of the invention, the building of the natural gas network model, the heating network model, the electric power network model and the coupling equipment model comprises the following steps:
Obtaining the power network model according to a node power injection equation and a node voltage equation;
the node power injection equation is:
；
；
wherein,for the node->Is +.>For the node->Is filled with reactive power, ">For the node->Voltage amplitude of>For the node->Voltage amplitude of>For the node->And said node->The real part of the admittance between +.>For the node->And->An imaginary part of the admittance therebetween;For the node->And said node->A voltage phase angle difference therebetween;
the node voltage equation is:
；
；
wherein,for the node->Voltage amplitude of>For a given value of the voltage amplitude, +.>To balance the voltage phase angle of the node +.>For a given value of the voltage phase angle, +.>For the supply voltage and the balance nodeAnd (5) collecting.
In this embodiment, the power network model includes a node power injection equation and a node voltage equation.
The node power injection equation is:
；
；
wherein,for node->Is +.>For node->Is filled with reactive power, ">For node->Voltage amplitude of>For node->Voltage amplitude of>For node->And node->The real part of the admittance between +. >For node->And->An imaginary part of the admittance therebetween;Is node->And node->A voltage phase angle difference therebetween;
the node voltage equation is:
；
；
wherein,for node->Voltage amplitude of>For a given value of the voltage amplitude, +.>To balance the voltage phase angle of the node +.>For a given value of the voltage phase angle>Is a set of supply voltage and balancing nodes.
According to the tide calculation method of the multi-energy coupling system, the power network model reflects the transmission and supply conditions of electric energy in the power grid by using the node power injection equation and the node voltage equation.
In the embodiment of the invention, the building of the natural gas network model, the heating network model, the electric power network model and the coupling equipment model further comprises:
obtaining the coupling equipment model according to a gas turbine model, a boiler model, a cogeneration unit model and a circulating pump model;
the gas turbine model is as follows:
；
wherein,for the natural gas flow consumed by the gas turbine, < > for the gas turbine>，And->For the energy consumption coefficient of the gas turbine, < >>Is the net calorific value of natural gas, +.>Output electrical power for the gas turbine;
the boiler model is as follows:
；
wherein,for the natural gas flow consumed by the boiler, +. >For the thermal power output by the boiler, +.>For the power conversion efficiency of the boiler, +.>Is the net heating value of the natural gas;
the cogeneration unit model is as follows:
；
wherein,for the natural gas flow consumed by the cogeneration unit, +.>Is the net calorific value of natural gas, +.>For the heat output of the cogeneration unit, < >>Electric power output for the cogeneration unit, < >>Power conversion efficiency for the cogeneration unit;
the circulating pump model is as follows:
；
wherein,for the consumed electrical power of the circulation pump, +.>For the inlet mass flow of the circulation pump, < > is>Acceleration of gravity, ++>Is water head pressure>Is the circulation pump efficiency. />
In the present embodiment, the coupling plant model includes a gas turbine model, a boiler model, a cogeneration unit model, and a circulation pump model.
Wherein, the gas turbine model is:
；
wherein,for the natural gas flow consumed by the gas turbine, +.>，And->For the energy consumption coefficient of the gas turbine, +.>Is the net calorific value of natural gas, +.>Output power for a gas turbineA power;
the boiler model is as follows:
；
wherein,for the natural gas flow consumed by the boiler, +.>For the thermal power output by the boiler, +.>For the power conversion efficiency of the boiler, < > for >Is the net heating value of natural gas;
the cogeneration unit model is as follows:
；
wherein,for the natural gas flow consumed by the cogeneration unit, +.>Is the net calorific value of natural gas, +.>For the heat power output by the cogeneration unit, < >>Electric power output by the cogeneration unit, < >>The power conversion efficiency of the cogeneration unit is;
the circulating pump model is as follows:
；
wherein,for the consumed electrical power of the circulation pump, +.>For the inlet mass flow of the circulation pump, +.>Acceleration of gravity, ++>Is water head pressure>Is the circulation pump efficiency.
According to the tide calculation method of the multi-energy coupling system, the coupling equipment model reflects the coupling equipment in the multi-energy coupling system by using a gas turbine model, a boiler model, a cogeneration unit model and a circulating pump model.
In the embodiment of the present invention, the obtaining, according to the steady-state model of the multi-energy coupling system, a nonlinear algebraic equation of the multi-energy coupling system includes:
obtaining related variables of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system;
obtaining the nonlinear algebraic equation according to the related variables;
the nonlinear algebraic equation is:；
wherein, ，As the related variables, the related variables include the temperature, flow, power, and voltage of the multi-energy coupling system.
In this embodiment, the nonlinear algebraic equation is:；
wherein,，as related variables, the related variables include temperature, flow, power and voltage of the multi-energy coupling system, +.>Is->Dimensional space vector, i.e.)>。
According to the tide calculation method of the multi-energy coupling system, a steady-state equation is simplified into an equation form through a nonlinear algebraic equation, and equations in all subsystems are combined.
In the embodiment of the present invention, the obtaining a fifth-order precision solution and a fourth-order precision solution of the multi-energy coupling system according to the nonlinear algebraic equation and the continuous newton method includes:
obtaining a nonlinear function according to the nonlinear algebraic equation;
the nonlinear function is:；
according to the nonlinear function, obtaining the five-order precision solution and the four-order precision solution of the multi-energy coupling system through the continuous Newton method;
the fifth-order precision solution is as follows:
；
wherein,for the five-order precision solution, +.>Is an intermediate variable +.>，Is a coefficient of->Is->Solution of multiple iterations,/->Is an iteration step length;
the fourth-order precision solution is:
；
Wherein,for the fourth order precision solution, +.>Is->Solution of multiple iterations,/->For the iteration step +.>Is a coefficient of->Is the intermediate variable.
In this embodiment, the obtaining a fifth-order precision solution and a fourth-order precision solution of the multi-energy coupling system according to the nonlinear algebraic equation and the continuous newton method includes:
obtaining a nonlinear function according to the nonlinear algebraic equation;
the nonlinear function is:；
according to the nonlinear function, obtaining the five-order precision solution and the four-order precision solution of the multi-energy coupling system through the continuous Newton method;
the fifth-order precision solution is as follows:
；
wherein,for the five-order precision solution, +.>Is an intermediate variable +.>，Is a coefficient of->Is->Solution of multiple iterations,/->Is an iteration step length;
wherein the coefficient is，The recommended values of (2) are shown in Table 1.
TABLE 1
The fourth-order precision solution is:
；
wherein,for the fourth order precision solution, +.>Is->Solution of multiple iterations,/->For the iteration step +.>Is a coefficient of->Is the intermediate variable;
wherein the coefficient isThe recommended values of (2) are shown in Table 2.
TABLE 2
According to the tide calculation method of the multi-energy coupling system, the fourth-order precision solution and the fifth-order precision solution are solved, so that the subsequent calculation of errors is facilitated.
In the embodiment of the present invention, the obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution includes:
adjusting the iteration step according to the difference value of the fifth-order precision solution and the fourth-order precision solution;
obtaining the tide of the multi-energy coupling system through the iteration step length;
the step of adjusting the iteration step according to the difference value between the fifth-order precision solution and the fourth-order precision solution comprises the steps of:
normalizing the difference value of the fifth-order precision solution and the fourth-order precision solution to obtain a tide calculation error expression of the multi-energy coupling system:
；
wherein,represents->Norms (F/F)>Is->Solution of multiple iterations,/->For iterative step length +.>A difference value between the five-order precision solution and the four-order precision solution; />
When (when)Less than a preset second error limit->When the iteration step length is reduced, the reduced iteration step length is obtained;
the iteration step after the reduction is as follows:
；
wherein,for said iteration step after said decrease, +.>As a minimum value of the iteration step,the iteration step length is the iteration step length;
repeatedly obtaining a five-order precision solution and a four-order precision solution of the multi-energy coupling system according to the nonlinear algebraic equation and the continuous Newton method;
When (when)Is greater than said preset second error limit +.>When the iteration step length is increased, the increased iteration step length is obtained;
the iteration step after the increase is as follows:
；
wherein,to be the instituteSaid iteration step after said increase, +.>The iteration step length is the iteration step length;
and when the number of times of increasing the iteration step is larger than the preset number of times, obtaining the tide of the multi-energy coupling system.
In this example, the continuous newton method is:
step (1): initial value of given variable，，；
Step (2): judgingIs->Norms->Whether or not to meet->Wherein->For the first error limit, if +.>Executing the step (3); if it meets->The calculation is finished;
step (3): solving a fourth-order precision solution and a fifth-order precision solution according to a formula, namely:
；
；
；
；/>
step (4): judgingWhether or not to meet->If it does not meet->Executing the step (5); if it meets->Executing the step (6);
step (5): reducing iteration step sizeAnd performing the steps (3) - (4);
step (6): increasing iteration stepSimultaneously update->；
Step (7): judgingWhether or not to meet->If not, executing the step (2); if so, the calculation ends.
According to the power flow calculation method of the multi-energy coupling system, iteration is carried out through continuous Newton, so that the convergence of power flow calculation of the multi-energy coupling system is improved, the operation speed is increased, and accurate references are provided for planning, reliability evaluation, operation scheduling and the like of the multi-energy coupling system.
Referring to fig. 2, the present invention further provides a load flow calculation device 100 of a multi-energy coupling system, including:
a steady-state model building module 110 for building a natural gas network model, a heating network model, an electric power network model, and a coupling device model; obtaining a steady-state model of the multi-energy coupling system according to the natural gas network model, the heating network model, the electric power network model and the coupling equipment model;
the power flow calculation module 120 is configured to obtain a nonlinear algebraic equation of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system; according to the nonlinear algebraic equation and the continuous Newton method, a fifth-order precision solution and a fourth-order precision solution of the multi-energy coupling system are obtained; and obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution.
According to the tide computing device of the multi-energy coupling system, a steady-state model is built through the natural gas network model, the heat supply network model, the electric power network model and the coupling equipment model, the tide of the multi-energy coupling system is computed based on the steady-state model by utilizing the continuous Newton method, the integral tide analysis of the multi-energy coupling system with multiple energy sources coupled by electricity, gas, heat and the like is realized, the energy system without a per unit model such as a gas-heat system is overcome through multi-model participation computation, the problem that the electric power system is difficult to be analogized by taking a variable per unit value as an initial value of each state quantity is solved, the tide computing precision is improved, meanwhile, the convergence of the tide computing of the multi-energy coupling system is improved by utilizing the continuous Newton method, and the operation speed is improved, so that accurate references are provided for planning, reliability evaluation, operation scheduling and the like of the multi-energy coupling system.
The invention also provides a computer device, which comprises a memory, a processor and a computer program stored on the memory and capable of running on the processor, and is characterized in that the processor realizes the load flow calculation method of the multi-energy coupling system when executing the computer program.
According to the computer equipment, a steady-state model is built through the natural gas network model, the heat supply network model, the electric power network model and the coupling equipment model, the power flow of the multi-energy coupling system is calculated based on the steady-state model by utilizing a continuous Newton method, the integral power flow analysis of the multi-energy coupling system with multiple energy sources such as electricity, gas and heat is realized, the energy system without per unit model such as a gas-heat system is overcome through multi-model participation calculation, the problem that the electric power system is difficult to be analogized by taking the per unit value of a variable as the initial value of each state quantity is solved, the power flow calculation precision is improved, meanwhile, the convergence of the power flow calculation of the multi-energy coupling system is improved by utilizing the continuous Newton method, the operation speed is improved, and accurate references are provided for planning, reliability evaluation, operation scheduling and the like of the multi-energy coupling system.
Those skilled in the art will appreciate that all or part of the processes in the methods of the above embodiments may be implemented by a computer program for instructing relevant hardware, where the program may be stored in a non-volatile computer readable storage medium, and where the program, when executed, may include processes in the embodiments of the methods described above. Any reference to memory, storage, database, or other medium used in embodiments provided herein may include non-volatile and/or volatile memory. The nonvolatile memory can include Read Only Memory (ROM), programmable ROM (PROM), electrically Programmable ROM (EPROM), electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double Data Rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous Link DRAM (SLDRAM), memory bus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), among others.
It should be noted that in this document, relational terms such as "first" and "second" and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element. The foregoing is only a specific embodiment of the invention to enable those skilled in the art to understand or practice the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (7)
1. The utility model provides a trend calculation method of a multi-energy coupling system, which is characterized by comprising the following steps:
constructing a natural gas network model, a heating network model, an electric power network model and a coupling equipment model;
obtaining a steady-state model of the multi-energy coupling system according to the natural gas network model, the heating network model, the electric power network model and the coupling equipment model;
obtaining a nonlinear algebraic equation of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system;
according to the nonlinear algebraic equation and the continuous Newton method, a fifth-order precision solution and a fourth-order precision solution of the multi-energy coupling system are obtained;
obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution;
the obtaining a nonlinear algebraic equation of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system comprises the following steps:
obtaining related variables of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system;
obtaining the nonlinear algebraic equation according to the related variables;
the nonlinear algebraic equation is: ；
wherein,，the related variables comprise the temperature, the flow, the power and the voltage of the multi-energy coupling system;
The obtaining a fifth-order precision solution and a fourth-order precision solution of the multi-energy coupling system according to the nonlinear algebraic equation and the continuous Newton method comprises the following steps:
obtaining a nonlinear function according to the nonlinear algebraic equation;
the nonlinear function is:；
according to the nonlinear function, obtaining the five-order precision solution and the four-order precision solution of the multi-energy coupling system through the continuous Newton method;
the fifth-order precision solution is as follows:
；
wherein,for the five-order precision solution, +.>Is an intermediate variable +.>，Is a coefficient of->Is->Solution of multiple iterations,/->Is an iteration step length;
the fourth-order precision solution is:
；
wherein,for the fourth order precision solution, +.>Is->Solution of multiple iterations,/->For the iteration step +.>Is a coefficient of->Is the intermediate variable;
the obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution comprises:
adjusting the iteration step according to the difference value of the fifth-order precision solution and the fourth-order precision solution;
obtaining the tide of the multi-energy coupling system through the iteration step length;
the step of adjusting the iteration step according to the difference value between the fifth-order precision solution and the fourth-order precision solution comprises the steps of:
Normalizing the difference value of the fifth-order precision solution and the fourth-order precision solution to obtain a tide calculation error expression of the multi-energy coupling system:
；
wherein,represents->Norms (F/F)>Is->Solution of multiple iterations,/->For iterative step length +.>A difference value between the five-order precision solution and the four-order precision solution;
when (when)Less than a preset second error limit->When the iteration step length is reduced, the reduced iteration step length is obtained;
the iteration step after the reduction is as follows:
；
wherein,for said iteration step after said decrease, +.>For the minimum value of the iteration step, +.>The iteration step length is the iteration step length;
repeatedly obtaining a five-order precision solution and a four-order precision solution of the multi-energy coupling system according to the nonlinear algebraic equation and the continuous Newton method;
when (when)Is greater than said preset second error limit +.>When the iteration step length is increased, the increased iteration step length is obtained;
the iteration step after the increase is as follows:
；
wherein,for said iteration step after said increase, +.>The iteration step length is the iteration step length;
and when the number of times of increasing the iteration step is larger than the preset number of times, obtaining the tide of the multi-energy coupling system.
2. The method for power flow calculation of a multi-energy coupling system according to claim 1, wherein the constructing a natural gas network model, a heating network model, an electric power network model, and a coupling device model comprises:
obtaining the natural gas network model according to an airflow equation, a node mass flow conservation equation and a compressor model;
the airflow equation is:
；
wherein,for the node of the multi-energy coupling system +.>And node->The gas flow in the pipeline between the two;Is a pipeline coefficient;For the node->Is a pressure of (1);For the node->Is a pressure of (1);Is a sign function, which satisfies +.>；Is the length of the pipe;Is the diameter of the pipe;A coefficient of friction for the pipe;Is the gas temperature;Is the gas compression coefficient;Is natural gas relative density;
the node mass flow conservation equation is:
；
wherein,for node->Is>For the pipeline->Is a gas mass flow of>For flowing into the node->Is a set of pipes;
the compressor model is as follows:
；
wherein,compression ratio of the compressor for the multi-energy coupling system, +.>For the pressure at the high-pressure side of the compressor, +. >Is the pressure on the low pressure side of the compressor.
3. The method for power flow calculation of a multi-energy coupling system according to claim 2, wherein the constructing a natural gas network model, a heating network model, an electric power network model, and a coupling device model further comprises:
obtaining the heating network model according to the hydraulic model and the thermodynamic model;
the thermodynamic model comprises a pipeline temperature transmission equation, a node temperature mixing equation and a node heat exchange equation, and the hydraulic model comprises a node mass flow continuous equation and a head loss equation;
wherein, pipeline temperature transmission equation is:
；
wherein,for the inlet temperature of the pipe, +.>For the outlet temperature of the pipe, +.>For ambient temperature->Is the specific heat capacity of water->For the mass flow of the pipe, +.>For the thermal coefficient of the pipe, +.>Is the length of the pipeline;
the node temperature mixing equation is:
；
；
wherein,for the node->Temperature of>For the pipeline->Mass flow of>For the pipeline->Is>For the pipeline->Is>For the node flowing into the pipeline +.>Pipe set of>For the node out of the pipe +. >Is a set of pipes;
the node heat exchange equation is as follows:
；
wherein,thermal power generated/consumed for said node, < >>Supplying water to the nodes with temperature->For the return water temperature of the node>Is the specific heat capacity of the water;
the mass flow continuous equation of the node is as follows:
；
wherein,for node->Is/are/is/are>Is a pipeline->Mass flow of>For flowing into the node->Is a set of pipes;
the head loss equation is:
；
wherein,for the pressure drop coefficient of the pipe, +.>For the pipeline->Mass flow of>For loops->Is provided.
4. The method for power flow calculation of a multi-energy coupling system according to claim 1, wherein the constructing a natural gas network model, a heating network model, an electric power network model, and a coupling device model comprises:
obtaining the power network model according to a node power injection equation and a node voltage equation;
the node power injection equation is:
；
；
wherein,for the node->Is +.>For the node->Is filled with reactive power, ">For the nodeVoltage amplitude of>For the node->Voltage amplitude of>For the node->And said node- >The real part of the admittance between +.>For the node->And->An imaginary part of the admittance therebetween;For the node->And said node->Voltage phase angle difference between>Is in the range of 1,2,3 … … n;
the node voltage equation is:
；
；
wherein,for the node->Voltage amplitude of>For a given value of the voltage amplitude, +.>To balance the voltage phase angle of the node +.>For a given value of the voltage phase angle, +.>Is a set of supply voltages and the balancing node.
5. The method for power flow calculation of a multi-energy coupling system according to claim 2, wherein the constructing a natural gas network model, a heating network model, an electric power network model, and a coupling device model further comprises:
obtaining the coupling equipment model according to a gas turbine model, a boiler model, a cogeneration unit model and a circulating pump model;
the gas turbine model is as follows:
；
wherein,for the natural gas flow consumed by the gas turbine, +.>，And->For the energy consumption coefficient of the gas turbine, < >>Is the net calorific value of natural gas, +.>Output electrical power for the gas turbine;
the boiler model is as follows:
；
wherein,for the natural gas flow consumed by the boiler, +.>For the thermal power output by the boiler, +. >For the power conversion efficiency of the boiler, +.>Is the net heating value of the natural gas;
the cogeneration unit model is as follows:
；
wherein,for the natural gas flow consumed by the cogeneration unit, +.>Is the net calorific value of natural gas, +.>For the heat output of the cogeneration unit, < >>Electric power output for the cogeneration unit, < >>For the thermoelectric powerThe power conversion efficiency of the co-production unit;
the circulating pump model is as follows:
；
wherein,for the consumed electrical power of the circulation pump, +.>For the inlet mass flow of the circulation pump, < > is>Acceleration of gravity, ++>Is water head pressure>Is the circulation pump efficiency.
6. A power flow calculation device of a multi-energy coupling system, comprising:
the steady-state model building module is used for building a natural gas network model, a heating network model, an electric power network model and a coupling equipment model; obtaining a steady-state model of the multi-energy coupling system according to the natural gas network model, the heating network model, the electric power network model and the coupling equipment model;
the power flow calculation module is used for obtaining a nonlinear algebraic equation of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system; according to the nonlinear algebraic equation and the continuous Newton method, a fifth-order precision solution and a fourth-order precision solution of the multi-energy coupling system are obtained; obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution;
The obtaining a nonlinear algebraic equation of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system comprises the following steps:
obtaining related variables of the multi-energy coupling system according to the steady-state model of the multi-energy coupling system;
obtaining the nonlinear algebraic equation according to the related variables;
the nonlinear algebraic equation is: ；
wherein,，the related variables comprise the temperature, the flow, the power and the voltage of the multi-energy coupling system;
the obtaining a fifth-order precision solution and a fourth-order precision solution of the multi-energy coupling system according to the nonlinear algebraic equation and the continuous Newton method comprises the following steps:
obtaining a nonlinear function according to the nonlinear algebraic equation;
the nonlinear function is:；
according to the nonlinear function, obtaining the five-order precision solution and the four-order precision solution of the multi-energy coupling system through the continuous Newton method;
the fifth-order precision solution is as follows:
；
wherein,for the fiveOrder accuracy solution->Is an intermediate variable +.>，Is a coefficient of->Is->Solution of multiple iterations,/->Is an iteration step length;
the fourth-order precision solution is:
；
wherein,for the fourth order precision solution, +. >Is->Solution of multiple iterations,/->For the iteration step +.>Is a coefficient of->Is the intermediate variable;
the obtaining the tide of the multi-energy coupling system according to the fifth-order precision solution and the fourth-order precision solution comprises:
adjusting the iteration step according to the difference value of the fifth-order precision solution and the fourth-order precision solution;
obtaining the tide of the multi-energy coupling system through the iteration step length;
the step of adjusting the iteration step according to the difference value between the fifth-order precision solution and the fourth-order precision solution comprises the steps of:
normalizing the difference value of the fifth-order precision solution and the fourth-order precision solution to obtain a tide calculation error expression of the multi-energy coupling system:
；
wherein,represents->Norms (F/F)>Is->Solution of multiple iterations,/->For iterative step length +.>A difference value between the five-order precision solution and the four-order precision solution;
when (when)Less than a preset second error limit->When the iteration step length is reduced, the reduced iteration step length is obtained;
the iteration step after the reduction is as follows:
；
wherein,for said iteration step after said decrease, +.>For the minimum value of the iteration step, +.>The iteration step length is the iteration step length;
Repeatedly obtaining a five-order precision solution and a four-order precision solution of the multi-energy coupling system according to the nonlinear algebraic equation and the continuous Newton method;
when (when)Is greater than said preset second error limit +.>When the iteration step length is increased, the increased iteration step length is obtained;
the iteration step after the increase is as follows:
；
wherein,for said iteration step after said increase, +.>The iteration step length is the iteration step length;
and when the number of times of increasing the iteration step is larger than the preset number of times, obtaining the tide of the multi-energy coupling system.
7. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the method of load flow calculation of the multi-energy coupling system according to any one of claims 1 to 5 when executing the computer program.
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