Electromechanical transient simulation method and system for alternating-current excitation variable-speed pumped storage unit

Abstract

The invention discloses an electromechanical transient simulation method and system for an alternating-current excitation variable-speed pumped storage unit, and belongs to the technical field of electromechanical transient simulation of a power system. The method provided by the invention comprises the following steps: determining a necessary simulation link according to a simulation time scale and an action frequency band of electromechanical transient simulation of the alternating-current excitation variable-speed pumped storage unit, and establishing a simulation module based on the necessary link; establishing a mathematical model of the simulation modules, and establishing an interaction relationship between electrical data and control signals among the simulation modules based on the coupling relationship among the necessary links; and establishing an electromechanical transient simulation model of the alternating-current excitation variable-speed pumped storage unit based on the mathematical model and the interaction relationship, and performing electromechanical transient simulation on the alternating-current excitation variable-speed pumped storage unit based on the electromechanical transient simulation model. According to the method, an electromechanical transient simulation framework of a large power grid is considered, the method can be conveniently applied to mainstream electromechanical transient simulation software, the analysis capability of the electromechanical transient simulation software can be improved, and the application range of the electromechanical transient simulation software can be widened.

Description

Technical Field

[0001] The present invention relates to the technical field of electromechanical transient simulation of power systems, and more specifically, to an electromechanical transient simulation method and system for an AC excitation variable speed pumped storage unit. Background Art

[0002] The input power of the conventional pumped storage unit in the pump working condition is directly related to the motor operating speed, and the synchronous speed of the motor is coupled with the power supply frequency of the power grid; the generator motor of the variable speed pumped storage unit adopts AC excitation and operates in a variable speed constant frequency mode. Compared with the conventional fixed speed pumped storage unit, the AC excitation variable speed pumped storage unit is very different from the structure to the operating characteristics. It has the same variable speed operation capability as the asynchronous machine; the input power is adjustable in the pump working condition; the operating performance is improved in the turbine working condition, etc. Therefore, the electromechanical transient simulation model of the AC excitation variable speed pumped storage unit cannot be replaced by a conventional pumped storage unit.

[0003] In terms of equipment structure, the excitation control and motor parts of AC excitation variable speed pumped storage units are similar to those of double-fed wind turbines, but there are obvious differences in capacity, speed range, and operating range. At the same time, it has unique governor control, coordinated control, hydraulic characteristics, and turbine parts. Therefore, the electromechanical transient simulation modeling method of double-fed wind turbines will not be directly applicable to AC excitation variable speed pumped storage units. Summary of the invention

[0004] In view of the above problems, the present invention proposes an electromechanical transient simulation method for an AC excitation variable speed pumped storage unit, comprising:

[0005] According to the simulation time scale and action frequency band of the electromechanical transient simulation of the AC excitation variable speed pumped storage unit, the necessary simulation links are determined, and a simulation module is established based on the necessary links;

[0006] Establishing a mathematical model of the simulation module, and establishing an interactive relationship between electrical data and control signals between the simulation modules based on the coupling relationship between the necessary links;

[0007] An electromechanical transient simulation model of an AC excitation variable speed pumped storage unit is established based on the mathematical model and the interaction relationship, and an electromechanical transient simulation of the AC excitation variable speed pumped storage unit is performed based on the electromechanical transient simulation model.

[0008] Optionally, based on the electromechanical transient simulation model, electromechanical transient simulation is performed on the AC excitation variable speed pumped storage unit, including:

[0009] For the electromechanical transient simulation model, different grid-connected interfaces under the xy-axis coordinates are established. By switching the different grid-connected interfaces of the electromechanical transient simulation model, the electromechanical transient simulation model is switched to a detailed electromechanical transient model or a simplified electromechanical transient model, and the initialization and equation solving links of the detailed electromechanical transient model or the simplified electromechanical transient model are executed to perform electromechanical transient simulation on the AC excitation variable speed pumped storage unit.

[0010] Optionally, determining the equipment components of the AC excitation variable speed pumped storage unit that meet the electromechanical time scale, DC voltage time scale and current time scale is a necessary part of the simulation.

[0011] Optional equipment components include:

[0012] Speed ​​governor, water pump and turbine, shaft system, asynchronous motor, converter, DC capacitor, coordinated control, converter current inner loop control, converter outer loop control, phase-locked loop, high and low voltage ride-through strategy, Chopper protection, Crowbar protection, speed and guide vane opening optimization.

[0013] Optional, simulation modules, including: optional modules and mandatory modules;

[0014] Among them, the simulation module established for the necessary links in the frequency range of 50 to 200 Hz is an optional module;

[0015] The optional modules include at least one of the following:

[0016] Asynchronous motor detailed model, converter model, DC capacitor model, rotor-side converter current inner loop control model, phase-locked loop model, grid-side converter control model, Chopper protection model and Crowbar protection model;

[0017] The converter model is established by using an average value model, and the DC side of the converter corresponding to the converter model is a controlled current source, and the AC side is a controlled voltage source;

[0018] The rotor-side converter current inner loop control model is established based on the rotor current deviation outputting a modulation voltage through a proportional-integral link, and the modulation voltage output by the current inner loop control link is modulated and limited, and then the AC-side controlled voltage value of the rotor-side converter model is determined according to the relationship between the modulation amount and the converter AC and DC voltages;

[0019] The output signal of the Crowbar protection model is used as the output of the rotor-side converter current inner loop control model and the enabling signal for modifying the detailed model parameters of the asynchronous motor;

[0020] Among them, the simulation model established for the necessary links in the frequency range of 0.1 to 50 Hz is a mandatory module;

[0021] The required modules include: a general link model and a specific link model.

[0022] Optional, general link models, including: speed control system model, water pump and turbine model, shaft system model, rotor side converter outer loop control model, high and low voltage ride-through strategy model, power-speed curve model and power-guide vane curve model;

[0023] The meaning of the output signal of the rotor-side converter outer loop control model is switched according to the model type, which is the rotor current in the detailed model and the total current in the simplified model;

[0024] The high and low voltage ride-through strategy model performs high and low voltage ride-through simulation by current limiting or changing the current reference output by the outer loop control of the rotor-side converter.

[0025] Optional, specific link models, including: coordinated control model.

[0026] Optional, detailed electromechanical transient model grid-connected interface, including: stator-side interface and grid-side converter interface;

[0027] Among them, the stator side interface is established through the asynchronous motor stator and rotor voltage equations;

[0028] The current output by the grid-side converter control model is used as a controlled current source to establish a grid-side converter interface.

[0029] Optionally, a controlled current source or a controlled voltage source is used as a grid-connected interface of the simplified electromechanical transient model.

[0030] On the other hand, the present invention also proposes an electromechanical transient simulation system for an AC excitation variable speed pumped storage unit, comprising:

[0031] A selection unit is used to determine the necessary links of the simulation according to the simulation time scale and action frequency band of the electromechanical transient simulation of the AC excitation variable speed pumped storage unit, and establish a simulation module based on the necessary links;

[0032] A coupling unit, used to establish a mathematical model of the simulation module, and to establish an interactive relationship between electrical data and control signals between the simulation modules based on the coupling relationship between the necessary links;

[0033] A simulation unit is used to establish an electromechanical transient simulation model of the AC excitation variable speed pumped storage unit based on the mathematical model and the interaction relationship, and to perform electromechanical transient simulation on the AC excitation variable speed pumped storage unit based on the electromechanical transient simulation model.

[0034] Optionally, based on the electromechanical transient simulation model, electromechanical transient simulation is performed on the AC excitation variable speed pumped storage unit, including:

[0035] For the electromechanical transient simulation model, different grid-connected interfaces under the xy-axis coordinates are established. By switching the different grid-connected interfaces of the electromechanical transient simulation model, the electromechanical transient simulation model is switched to a detailed electromechanical transient model or a simplified electromechanical transient model, and the initialization and equation solving links of the detailed electromechanical transient model or the simplified electromechanical transient model are executed to perform electromechanical transient simulation on the AC excitation variable speed pumped storage unit.

[0036] Optionally, the selection unit determines the equipment components of the AC excitation variable speed pumped storage unit that meet the electromechanical time scale, DC voltage time scale and current time scale as a necessary part of the simulation.

[0037] Optional equipment components include:

[0038] Speed ​​governor, water pump and turbine, shaft system, asynchronous motor, converter, DC capacitor, coordinated control, converter current inner loop control, converter outer loop control, phase-locked loop, high and low voltage ride-through strategy, Chopper protection, Crowbar protection, speed and guide vane opening optimization.

[0039] Optional, simulation modules, including: optional modules and mandatory modules;

[0040] Among them, the simulation module established for the necessary links in the frequency range of 50 to 200 Hz is an optional module;

[0041] The optional modules include at least one of the following:

[0042] Asynchronous motor detailed model, converter model, DC capacitor model, rotor-side converter current inner loop control model, phase-locked loop model, grid-side converter control model, Chopper protection model and Crowbar protection model;

[0043] The converter model is established by using an average value model, and the DC side of the converter corresponding to the converter model is a controlled current source, and the AC side is a controlled voltage source;

[0044] The rotor-side converter current inner loop control model is established based on the rotor current deviation outputting a modulation voltage through a proportional-integral link, and the modulation voltage output by the current inner loop control link is modulated and limited, and then the AC-side controlled voltage value of the rotor-side converter model is determined according to the relationship between the modulation amount and the converter AC and DC voltages;

[0045] The output signal of the Crowbar protection model is used as the output of the rotor-side converter current inner loop control model and the enabling signal for modifying the detailed model parameters of the asynchronous motor;

[0046] Among them, the simulation model established for the necessary links in the frequency range of 0.1 to 50 Hz is a mandatory module;

[0047] The required modules include: a general link model and a specific link model.

[0048] Optional, general link models, including: speed control system model, water pump and turbine model, shaft system model, rotor side converter outer loop control model, high and low voltage ride-through strategy model, power-speed curve model and power-guide vane curve model;

[0049] The meaning of the output signal of the rotor-side converter outer loop control model is switched according to the model type, which is the rotor current in the detailed model and the total current in the simplified model;

[0050] The high and low voltage ride-through strategy model performs high and low voltage ride-through simulation by current limiting or changing the current reference output by the outer loop control of the rotor-side converter.

[0051] Optional, specific link models, including: coordinated control model.

[0052] Optional, detailed electromechanical transient model grid-connected interface, including: stator-side interface and grid-side converter interface;

[0053] Among them, the stator side interface is established through the asynchronous motor stator and rotor voltage equations;

[0054] The current output by the grid-side converter control model is used as a controlled current source to establish a grid-side converter interface.

[0055] Optionally, a controlled current source or a controlled voltage source is used as a grid-connected interface of the simplified electromechanical transient model.

[0056] In yet another aspect, the present invention further provides a computing device, comprising: one or more processors;

[0057] a processor for executing one or more programs;

[0058] When the one or more programs are executed by the one or more processors, the above-described method is implemented.

[0059] In yet another aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed, the method described above is implemented.

[0060] Compared with the prior art, the present invention has the following beneficial effects:

[0061] The present invention provides an electromechanical transient simulation method for an AC excitation variable speed pumped storage unit, comprising: determining the necessary links of the simulation according to the simulation time scale and action frequency band of the electromechanical transient simulation of the AC excitation variable speed pumped storage unit, and establishing a simulation module based on the necessary links; establishing a mathematical model of the simulation module, and establishing an interactive relationship between electrical data and control signals between each simulation module based on the coupling relationship between the necessary links; establishing an electromechanical transient simulation model of the AC excitation variable speed pumped storage unit based on the mathematical model and the interactive relationship, and performing electromechanical transient simulation on the AC excitation variable speed pumped storage unit based on the electromechanical transient simulation model. The present invention takes into account the electromechanical transient simulation framework of large power grids, can be easily applied to mainstream electromechanical transient simulation software, and can improve the analysis capability and application scope of electromechanical transient simulation software. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 is a flow chart of the method of the present invention;

[0063] Figure 2 Flow chart of an embodiment of the method of the present invention;

[0064] Figure 3 It is a model diagram of the method of the present invention;

[0065] Figure 4 The active and reactive power curves of the electromechanical transient simulation of the AC excitation variable speed pumped storage unit according to the method of the present invention;

[0066] Figure 5 It is a structural diagram of the system of the present invention. DETAILED DESCRIPTION

[0067] Now, exemplary embodiments of the present invention are described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0068] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0069] Embodiment 1:

[0070] The present invention proposes an electromechanical transient simulation method for an AC excitation variable speed pumped storage unit. Figure 1As shown, including:

[0071] Step 1: Determine the necessary links of the simulation according to the simulation time scale and action frequency band of the electromechanical transient simulation of the AC excitation variable speed pumped storage unit, and establish a simulation module based on the necessary links;

[0072] Step 2: Establish a mathematical model of the simulation module, and establish an interactive relationship between electrical data and control signals between the simulation modules based on the coupling relationship between the necessary links;

[0073] Step 3: Establish an electromechanical transient simulation model of the AC excitation variable speed pumped storage unit based on the mathematical model and the interaction relationship; and perform electromechanical transient simulation on the AC excitation variable speed pumped storage unit based on the electromechanical transient simulation model.

[0074] Wherein, based on the electromechanical transient simulation model, the electromechanical transient simulation of the AC excitation variable speed pumped storage unit is performed, including:

[0075] For the electromechanical transient simulation model, different grid-connected interfaces under the xy-axis coordinates are established. By switching the different grid-connected interfaces of the electromechanical transient simulation model, the electromechanical transient simulation model is switched to a detailed electromechanical transient model or a simplified electromechanical transient model, and the initialization and equation solving links of the detailed electromechanical transient model or the simplified electromechanical transient model are executed to perform electromechanical transient simulation on the AC excitation variable speed pumped storage unit.

[0076] Among them, determining the equipment components of the AC excitation variable speed pumped storage unit that meet the electromechanical time scale, DC voltage time scale and current time scale is a necessary part of the simulation.

[0077] Among them, the equipment components include:

[0078] Speed ​​governor, water pump and turbine, shaft system, asynchronous motor, converter, DC capacitor, coordinated control, converter current inner loop control, converter outer loop control, phase-locked loop, high and low voltage ride-through strategy, Chopper protection, Crowbar protection, speed and guide vane opening optimization.

[0079] Among them, the simulation module includes: optional modules and mandatory modules;

[0080] Among them, the simulation module established for the necessary links in the frequency range of 50 to 200 Hz is an optional module;

[0081] The optional modules include at least one of the following:

[0082] Asynchronous motor detailed model, converter model, DC capacitor model, rotor-side converter current inner loop control model, phase-locked loop model, grid-side converter control model, Chopper protection model and Crowbar protection model;

[0083] The converter model is established by using an average value model, and the DC side of the converter corresponding to the converter model is a controlled current source, and the AC side is a controlled voltage source;

[0084] The rotor-side converter current inner loop control model is established based on the rotor current deviation outputting a modulation voltage through a proportional-integral link, and the modulation voltage output by the current inner loop control link is modulated and limited, and then the AC-side controlled voltage value of the rotor-side converter model is determined according to the relationship between the modulation amount and the converter AC and DC voltages;

[0085] The output signal of the Crowbar protection model is used as the output of the rotor-side converter current inner loop control model and the enabling signal for modifying the detailed model parameters of the asynchronous motor;

[0086] Among them, the simulation model established for the necessary links in the frequency range of 0.1 to 50 Hz is a mandatory module;

[0087] The required modules include: a general link model and a specific link model.

[0088] Among them, the general link models include: speed control system model, water pump and turbine model, shaft system model, rotor side converter outer loop control model, high and low voltage ride-through strategy model, power-speed curve model and power-guide vane curve model;

[0089] The meaning of the output signal of the rotor-side converter outer loop control model is switched according to the model type. In the case of a detailed model, it is the rotor current, and in the case of a simplified model, it is the total current. ;

[0090] The high and low voltage ride-through strategy model performs high and low voltage ride-through simulation by current limiting or changing the current reference output by the outer loop control of the rotor-side converter.

[0091] Among them, the specific link models include: coordination control model.

[0092] Among them, the grid-connected interface of the detailed electromechanical transient model includes: stator-side interface and grid-side converter interface;

[0093] Among them, the stator side interface is established through the asynchronous motor stator and rotor voltage equations;

[0094] The current output by the grid-side converter control model is used as a controlled current source to establish a grid-side converter interface.

[0095] Wherein, a controlled current source or a controlled voltage source is used as a grid-connected interface of a simplified electromechanical transient model.

[0096] The present invention will be further described below in conjunction with embodiments:

[0097] Specific steps are as follows Figure 2 As shown:

[0098] In the first step, according to the various components of the AC excitation variable speed pumped storage unit equipment, the time scale and action frequency band of each link such as the speed control system, water pump and turbine, shaft system, asynchronous motor, converter, DC capacitor, coordinated control, converter current inner loop control, converter outer loop control, phase-locked loop, high and low voltage ride-through strategy, Chopper protection, Crowbar protection, speed and guide vane opening optimization are analyzed, and the necessary links that meet the electromechanical time scale, DC voltage time scale and current time scale are determined as the simulation module of electromechanical transient simulation.

[0099] According to the modeling details of the converter control system and asynchronous motors, converters, DC capacitors and other links, the simulation requirements in different simulation scenarios are met, including mandatory modules and optional modules, where the mandatory modules include common links and specific links. For the links in the frequency range of 50 to 200 Hz as optional modules, the detailed electromechanical transient model must be considered, and the simplified electromechanical transient model is not considered. For other links in the frequency range of 0.1 to 50 Hz as mandatory modules, both the detailed electromechanical transient model and the simplified electromechanical transient model need to be considered. The model structure is as follows Figure 3 As shown;

[0100] The second step is to establish a mathematical model suitable for electromechanical transient simulation for each link of the simulation module in step one, and according to the coupling relationship of each link, establish the interactive relationship between electrical data and control signals between each simulation module under different types of models including optional modules and those not containing optional modules.

[0101] Among them, all parameters are calibrated with the local capacity, and the converter current inner loop control, converter outer loop control, phase-locked loop, and asynchronous motor model all use the dq coordinate system and a unified coordinate orientation.

[0102] The third step is to establish the grid-connected interface of the electromechanical transient simulation model of multiple types of AC excitation variable speed pumped storage units under the xy axis coordinates, realize the joint simulation calculation of the model and the external power grid, perform model initialization and equation solving, and complete the electromechanical transient simulation modeling. The simulation calculation results are as follows: Figure 4 As shown;

[0103] Among them, the detailed electromechanical transient model and the simplified electromechanical transient model use different grid-connected interfaces and can be automatically switched according to the model selection.

[0104] The optional modules in the first step mainly include asynchronous motor model, converter model, DC capacitor, rotor-side converter current inner loop control, phase-locked loop, grid-side converter control, Chopper protection, and Crowbar protection. The common links of the mandatory modules include speed control system, water pump and turbine, shaft system, rotor-side converter outer loop control, high and low voltage ride-through strategy, power-speed curve, and power-guide vane curve; the specific link is coordinated control, according to the engineering configuration. The model structure includes optional modules and mandatory modules, which are adaptively selected according to the model type used in the simulation.

[0105] In the second step, the asynchronous motor model is based on the stator and rotor flux equations and voltage equations, without considering the stator flux change and the turns ratio. The converter model adopts the average value model, with the DC side as a controlled current source and the AC side as a controlled voltage source under the dq axis respectively.

[0106] The inner loop current control of the rotor converter does not consider the voltage cross term, but only considers the rotor current deviation to output the modulation voltage through the proportional integral link. Without considering the modulation link, the modulation voltages Vmd and Vmq output by the inner loop current control are modulated and limited, and the controlled voltage on the AC side of the converter is obtained by using the relationship between the modulation amount and the AC and DC voltage of the converter. Among them, when the Crowbar protection is not started, the controlled voltage value on the AC side of the rotor converter is equal to the rotor voltage of the asynchronous motor.

[0107] The meaning of the output signal of the rotor converter outer loop control can be flexibly set according to the model type. The active control part of the rotor converter outer loop can select speed control or power control. The output is the rotor current d-axis reference value when the detailed electromechanical transient model is used, and the output is the total current d-axis reference value when the simplified electromechanical transient model is used; the reactive control part can select constant reactive control or constant voltage control. The output is the rotor current q-axis reference value when the detailed electromechanical model is used, and the output is the total current q-axis reference value when the simplified electromechanical transient model is used.

[0108] The high and low voltage ride-through strategy is implemented by current limiting or changing the current reference output by the outer loop control of the rotor converter. The grid-side converter control can ignore the inner current loop and only consider the outer loop DC voltage loop and power loop to control the output grid-side current reference value, ignoring the grid-side converter model.

[0109] The Crowbar protection output signal is used as the enable signal for the rotor side inner loop current control output and the asynchronous motor rotor parameter modification. When the Crowbar protection is put into operation, the rotor side inner loop current control output modulation voltage is set to 0 to simulate the inverter lockout. When the Crowbar protection is put into operation, the asynchronous motor model corrects the rotor resistance related parameters, and the motor rotor resistance is corrected to the electronic rotor resistance plus the Crowbar protection circuit resistance.

[0110] The coordinated control model realizes the switching of different control modes of the speed control system and the excitation control system under different operating conditions of the water pump or power generation.

[0111] In the third step, the grid-connected interface uses xy axis coordinates. The detailed electromechanical transient model grid-connected interface is divided into two parts: the stator side and the grid-side converter. The stator side uses the stator and rotor voltage equations of the asynchronous motor to establish a voltage source grid-connected interface. The grid-side converter part uses a controlled current source to interface with the grid. The grid-connected interface of the simplified electromechanical transient model can use a controlled current source or a controlled voltage source. The injected current of the grid-connected interface uses the system standard during joint calculation.

[0112] The present invention does not require a large number of model parameters to be modified, and different types of simulation models can be flexibly switched only through mode selection.

[0113] For the simulation scenario of accessing a low short-circuit ratio weak system, the present invention adaptively selects an AC excitation variable speed pumped storage detailed unit electromechanical transient simulation model, which is beneficial to improving the electromechanical transient simulation accuracy.

[0114] For simulation scenarios connected to strong systems, the present invention adaptively selects an AC-excited variable-speed pumped storage unit to simplify the electromechanical transient simulation model, thereby improving the simulation speed while ensuring that the simulation accuracy meets the requirements.

[0115] The simulation method proposed in the present invention takes into account the electromechanical transient simulation framework of large power grids, can be easily applied to mainstream electromechanical transient simulation software, and can improve the analysis capability and application scope of electromechanical transient simulation software.

[0116] Embodiment 2:

[0117] The present invention also proposes an electromechanical transient simulation system 200 for an AC excitation variable speed pumped storage unit, such as Figure 5 As shown, including:

[0118] A selection unit 201 is used to determine necessary simulation links according to the simulation time scale and action frequency band of the electromechanical transient simulation of the AC excitation variable speed pumped storage unit, and establish a simulation module based on the necessary links;

[0119] A coupling unit 202, used to establish a mathematical model of the simulation module, and to establish an interactive relationship between electrical data and control signals between the simulation modules based on the coupling relationship between the necessary links;

[0120] The simulation unit 203 is used to establish an electromechanical transient simulation model of the AC excitation variable speed pumped storage unit based on the mathematical model and the interaction relationship, and perform electromechanical transient simulation on the AC excitation variable speed pumped storage unit based on the electromechanical transient simulation model.

[0121] Wherein, based on the electromechanical transient simulation model, the electromechanical transient simulation of the AC excitation variable speed pumped storage unit is performed, including:

[0122] For the electromechanical transient simulation model, different grid-connected interfaces under the xy-axis coordinates are established. By switching the different grid-connected interfaces of the electromechanical transient simulation model, the electromechanical transient simulation model is switched to a detailed electromechanical transient model or a simplified electromechanical transient model, and the initialization and equation solving links of the detailed electromechanical transient model or the simplified electromechanical transient model are executed to perform electromechanical transient simulation on the AC excitation variable speed pumped storage unit.

[0123] The selection unit 201 determines the equipment components of the AC excitation variable speed pumped storage unit that meet the electromechanical time scale, the DC voltage time scale and the current time scale as necessary links for simulation.

[0124] Among them, the equipment components include:

[0125] Speed ​​governor, water pump and turbine, shaft system, asynchronous motor, converter, DC capacitor, coordinated control, converter current inner loop control, converter outer loop control, phase-locked loop, high and low voltage ride-through strategy, Chopper protection, Crowbar protection, speed and guide vane opening optimization.

[0126] Among them, the simulation module includes: optional modules and mandatory modules;

[0127] Among them, the simulation module established for the necessary links in the frequency range of 50 to 200 Hz is an optional module;

[0128] The optional modules include at least one of the following:

[0129] Asynchronous motor detailed model, converter model, DC capacitor model, rotor-side converter current inner loop control model, phase-locked loop model, grid-side converter control model, Chopper protection model and Crowbar protection model;

[0130] The converter model is established by using an average value model, and the DC side of the converter corresponding to the converter model is a controlled current source, and the AC side is a controlled voltage source;

[0131] The rotor-side converter current inner loop control model is established based on the rotor current deviation outputting a modulation voltage through a proportional-integral link, and the modulation voltage output by the current inner loop control link is modulated and limited, and then the AC-side controlled voltage value of the rotor-side converter model is determined according to the relationship between the modulation amount and the converter AC and DC voltages;

[0132] The output signal of the Crowbar protection model is used as the output of the rotor-side converter current inner loop control model and the enabling signal for modifying the detailed model parameters of the asynchronous motor;

[0133] Among them, the simulation model established for the necessary links in the frequency range of 0.1 to 50 Hz is a mandatory module;

[0134] The required modules include: a general link model and a specific link model.

[0135] Among them, the general link models include: speed control system model, water pump and turbine model, shaft system model, rotor side converter outer loop control model, high and low voltage ride-through strategy model, power-speed curve model and power-guide vane curve model;

[0136] The meaning of the output signal of the rotor-side converter outer loop control model is switched according to the model type, which is the rotor current in the detailed model and the total current in the simplified model;

[0137] The high and low voltage ride-through strategy model performs high and low voltage ride-through simulation by current limiting or changing the current reference output by the outer loop control of the rotor-side converter.

[0138] Among them, the specific link models include: coordination control model.

[0139] Among them, the grid-connected interface of the detailed electromechanical transient model includes: stator-side interface and grid-side converter interface;

[0140] Among them, the stator side interface is established through the asynchronous motor stator and rotor voltage equations;

[0141] The current output by the grid-side converter control model is used as a controlled current source to establish a grid-side converter interface.

[0142] Wherein, a controlled current source or a controlled voltage source is used as a grid-connected interface of a simplified electromechanical transient model.

[0143] The present invention takes into account the electromechanical transient simulation framework of a large power grid, can be conveniently applied to mainstream electromechanical transient simulation software, and can enhance the analysis capability and application scope of the electromechanical transient simulation software.

[0144] Embodiment 3:

[0145] Based on the same inventive concept, the present invention also provides a computer device, which includes a processor and a memory, wherein the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, and is specifically suitable for loading and executing one or more instructions in the computer storage medium to implement the corresponding method flow or corresponding functions, so as to implement the steps of the method in the above embodiment.

[0146] Embodiment 4:

[0147] Based on the same inventive concept, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It is understandable that the computer-readable storage medium here can include both a built-in storage medium in a computer device and an extended storage medium supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by a processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of the method in the above embodiment.

[0148] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes. The schemes in the embodiments of the present invention may be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0149] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0150] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0151] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0152] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0153] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for electromechanical transient simulation of an AC excitation variable speed pumped storage unit, characterized in that: include: According to the simulation time scale and action frequency band of the electromechanical transient simulation of the AC excitation variable speed pumped storage unit, the necessary simulation links are determined, and a simulation module is established based on the necessary links; Establishing a mathematical model of the simulation module, and establishing an interactive relationship between electrical data and control signals between the simulation modules based on the coupling relationship between the necessary links; An electromechanical transient simulation model of an AC excitation variable speed pumped storage unit is established based on the mathematical model and the interaction relationship, and an electromechanical transient simulation of the AC excitation variable speed pumped storage unit is performed based on the electromechanical transient simulation model.

2. The electromechanical transient simulation method according to claim 1, characterized in that: The electromechanical transient simulation of the AC excitation variable speed pumped storage unit based on the electromechanical transient simulation model includes: For the electromechanical transient simulation model, different grid-connected interfaces under the xy-axis coordinates are established. By switching the different grid-connected interfaces of the electromechanical transient simulation model, the electromechanical transient simulation model is switched to a detailed electromechanical transient model or a simplified electromechanical transient model, and the initialization and equation solving links of the detailed electromechanical transient model or the simplified electromechanical transient model are executed to perform electromechanical transient simulation on the AC excitation variable speed pumped storage unit.

3. The electromechanical transient simulation method according to claim 1, characterized in that: Determine the equipment components of the AC excitation variable speed pumped storage unit that meet the electromechanical time scale, DC voltage time scale and current time scale as a necessary part of the simulation.

4. The electromechanical transient simulation method according to claim 3, characterized in that: The components of the equipment include: Speed ​​control system, water pump and turbine, shaft system, asynchronous motor, converter, DC capacitor, coordinated control, converter current inner loop control, converter outer loop control, phase-locked loop, high and low voltage ride-through strategy, Chopper protection, Crowbar protection, speed and guide vane opening optimization.

5. The electromechanical transient simulation method according to claim 1, characterized in that: The simulation module includes: an optional module and a mandatory module; Among them, the simulation module established for the necessary links in the frequency range of 50 to 200 Hz is an optional module; The optional modules include at least one of the following: Asynchronous motor detailed model, converter model, DC capacitor model, rotor-side converter current inner loop control model, phase-locked loop model, grid-side converter control model, Chopper protection model and Crowbar protection model; The converter model is established by using an average value model, and the DC side of the converter corresponding to the converter model is a controlled current source, and the AC side is a controlled voltage source; The rotor-side converter current inner loop control model is established based on the rotor current deviation outputting a modulation voltage through a proportional-integral link, and the modulation voltage output by the current inner loop control link is modulated and limited, and then the AC-side controlled voltage value of the rotor-side converter model is determined according to the relationship between the modulation amount and the converter AC and DC voltages; The output signal of the Crowbar protection model is used as the output of the rotor-side converter current inner loop control model and the enabling signal for modifying the detailed model parameters of the asynchronous motor; Among them, the simulation model established for the necessary links in the frequency range of 0.1 to 50 Hz is a mandatory module; The required modules include: a general link model and a specific link model.

6. The electromechanical transient simulation method according to claim 5, characterized in that: The general link model includes: a speed control system model, a water pump and turbine model, a shaft system model, a rotor side converter outer ring control model, a high and low voltage ride-through strategy model, a power-speed curve model and a power-guide vane curve model; The meaning of the output signal of the rotor-side converter outer loop control model is switched according to the model type, which is the rotor current in the detailed model and the total current in the simplified model; The high and low voltage ride-through strategy model performs high and low voltage ride-through simulation by current limiting or changing the current reference output by the outer loop control of the rotor-side converter.

7. The electromechanical transient simulation method according to claim 5, characterized in that: The specific link model includes: a coordination control model.

8. The electromechanical transient simulation method according to claim 2, characterized in that: The grid-connected interface of the detailed electromechanical transient model includes: a stator-side interface and a grid-side converter interface; Among them, the stator side interface is established through the asynchronous motor stator and rotor voltage equations; The current output by the grid-side converter control model is used as a controlled current source to establish a grid-side converter interface.

9. The electromechanical transient simulation method according to claim 2, characterized in that: A controlled current source or a controlled voltage source is used as the grid-connected interface of the simplified electromechanical transient model.

10. An electromechanical transient simulation system for an AC excitation variable speed pumped storage unit, characterized in that: include: A selection unit is used to determine the necessary links of the simulation according to the simulation time scale and action frequency band of the electromechanical transient simulation of the AC excitation variable speed pumped storage unit, and establish a simulation module based on the necessary links; A coupling unit, used to establish a mathematical model of the simulation module, and to establish an interactive relationship between electrical data and control signals between the simulation modules based on the coupling relationship between the necessary links; A simulation unit is used to establish an electromechanical transient simulation model of the AC excitation variable speed pumped storage unit based on the mathematical model and the interaction relationship, and to perform electromechanical transient simulation on the AC excitation variable speed pumped storage unit based on the electromechanical transient simulation model.

11. The electromechanical transient simulation system according to claim 10, characterized in that: The electromechanical transient simulation of the AC excitation variable speed pumped storage unit based on the electromechanical transient simulation model includes: For the electromechanical transient simulation model, different grid-connected interfaces under the xy-axis coordinates are established. By switching the different grid-connected interfaces of the electromechanical transient simulation model, the electromechanical transient simulation model is switched to a detailed electromechanical transient model or a simplified electromechanical transient model, and the initialization and equation solving links of the detailed electromechanical transient model or the simplified electromechanical transient model are executed to perform electromechanical transient simulation on the AC excitation variable speed pumped storage unit.

12. The electromechanical transient simulation system according to claim 10, characterized in that: The selection unit determines the equipment components of the AC excitation variable speed pumped storage unit that meet the electromechanical time scale, DC voltage time scale and current time scale as a necessary part of the simulation.

13. The electromechanical transient simulation system according to claim 12, characterized in that: The components of the equipment include: Speed ​​control system, water pump and turbine, shaft system, asynchronous motor, converter, DC capacitor, coordinated control, converter current inner loop control, converter outer loop control, phase-locked loop, high and low voltage ride-through strategy, Chopper protection, Crowbar protection, speed and guide vane opening optimization.

14. The electromechanical transient simulation system according to claim 10, characterized in that: The simulation module includes: an optional module and a mandatory module; Among them, the simulation module established for the necessary links in the frequency range of 50 to 200 Hz is an optional module; The optional modules include at least one of the following: Asynchronous motor detailed model, converter model, DC capacitor model, rotor-side converter current inner loop control model, phase-locked loop model, grid-side converter control model, Chopper protection model and Crowbar protection model; The converter model is established by using an average value model, and the DC side of the converter corresponding to the converter model is a controlled current source, and the AC side is a controlled voltage source; The rotor-side converter current inner loop control model is established based on the rotor current deviation outputting a modulation voltage through a proportional-integral link, and the modulation voltage output by the current inner loop control link is modulated and limited, and then the AC-side controlled voltage value of the rotor-side converter model is determined according to the relationship between the modulation amount and the converter AC and DC voltages; The output signal of the Crowbar protection model is used as the output of the rotor-side converter current inner loop control model and the enabling signal for modifying the detailed model parameters of the asynchronous motor; Among them, the simulation model established for the necessary links in the frequency range of 0.1 to 50 Hz is a mandatory module; The required modules include: a general link model and a specific link model.

15. The electromechanical transient simulation system according to claim 14, characterized in that: The general link model includes: a speed control system model, a water pump and turbine model, a shaft system model, a rotor side converter outer ring control model, a high and low voltage ride-through strategy model, a power-speed curve model and a power-guide vane curve model; The meaning of the output signal of the rotor-side converter outer loop control model is switched according to the model type, which is the rotor current in the detailed model and the total current in the simplified model; The high and low voltage ride-through strategy model performs high and low voltage ride-through simulation by current limiting or changing the current reference output by the outer loop control of the rotor-side converter.

16. The electromechanical transient simulation system according to claim 14, characterized in that: The specific link model includes: a coordination control model.

17. The electromechanical transient simulation system according to claim 11, characterized in that: The grid-connected interface of the detailed electromechanical transient model includes: a stator-side interface and a grid-side converter interface; Among them, the stator side interface is established through the asynchronous motor stator and rotor voltage equations; The current output by the grid-side converter control model is used as a controlled current source to establish a grid-side converter interface.

18. The electromechanical transient simulation system according to claim 11, characterized in that: A controlled current source or a controlled voltage source is used as the grid-connected interface of the simplified electromechanical transient model.

19. A computer device, characterized in that: include: one or more processors; a processor for executing one or more programs; When the one or more programs are executed by the one or more processors, the method according to any one of claims 1 to 9 is implemented.

20. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed, the method according to any one of claims 1 to 9 is implemented.

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