Simulation modeling method for generator body and accessories thereof for transient calculation

Abstract

The invention relates to a simulation modeling method for a generator body and accessories thereof for transient calculation, which comprises the following steps of: constructing generator body models with different complexities, and simplifying the generator models; according to the construction result of the generator body model, constructing a generator accessory model matched with the generator body model, considering dynamic characteristics in a prime mover model, and simulating transient dynamic processes of the generator and accessories thereof; parameters of the generator body model and the accessory model are initialized, a swing angle is calculated according to generator terminal voltage and current, and the calculated swing angle serves as an input parameter and is stored in a parameter data structure of the generator model; and performing simultaneous solution on the generator body and the accessory model, performing transient simulation calculation, and dynamically adjusting the simulation precision by adjusting the orders of the generator body models and selecting the generator body models with different complexities. And real and reliable modeling and data preparation are provided for accurate and complete simulation of a complex power grid catastrophe and recovery process.

Description

Technical Field

[0001] The present invention belongs to the technical field of transient calculation of power systems, and more specifically, relates to a simulation modeling method of a generator body and its accessories for transient calculation. Background Art

[0002] With the continuous advancement of the construction of new power systems, various new types of grid-connected entities are connected and put into operation, making the characteristics and operating conditions of regional power grid systems increasingly complex. Once a large-scale power outage occurs, the power grid will be paralyzed, which will have a huge impact on normal production and life.

[0003] In order to avoid the above-mentioned hidden dangers, it is necessary to accurately and completely simulate the complex power grid disaster and recovery process, reproduce the power grid disaster and recovery process, and reveal the power grid disaster process. It is necessary to perform transient stability simulation calculations of complex power systems. This requires the construction of steady-state and electromechanical transient models of the generator body, control link model, prime mover (prime mover, turbine, steam turbine) and speed regulator model, and the input of model parameters required for power system transient calculation participates in the calculation.

[0004] In transient calculations, with the introduction of new equipment, there will be many PID (proportional integral differential) control models in the excitation link, prime mover, speed regulator, etc., which will affect the changes of transient variables in the time domain. In order to simulate the dynamic process of power grid disasters and recovery, and to simulate these models, in addition to writing simulation codes for these models in a targeted manner, it is also necessary to prepare respective data for these models in different links. Therefore, before performing transient calculations, data input must be done well so that data can be properly prepared for all models to realize the modeling process.

[0005] The existing modeling process of transient calculation of power system is relatively complicated, the data input rules are cumbersome, not intuitive enough, and cannot directly correspond to the actual physical meaning. It needs to be edited by referring to the operation manual, which is prone to errors. In addition, when new equipment is added, the modeling and data input links are not flexible enough. It is impossible to intuitively, comprehensively and flexibly organize the model data required for transient calculation of power system and input them into the system for simulation calculation. Summary of the invention

[0006] In order to solve the deficiencies in the prior art, the present invention provides a simulation modeling method for the generator body and its accessories for transient calculation, constructs three generator body models respectively, constructs the generator accessory model based on the transfer function, classifies the generator body and accessory models required for transient calculation, prepares the required data in different links, establishes a data input system for transient calculation of the power system, and prepares a stable and reliable data input stream for calculation. At the same time, a set of standardized equipment modeling system is formed so that new models can be added flexibly when new equipment is added, and provides real and reliable models and data preparation for accurate and complete simulation of complex power grid disasters and recovery processes.

[0007] The present invention adopts the following technical solution.

[0008] A first aspect of the present invention provides a simulation modeling method for a generator body and its accessories for transient calculation, comprising the following steps:

[0009] Construct generator models of different complexity and simplify the generator models according to simulation requirements;

[0010] According to the construction results of the generator body model, a generator accessory model matching the generator body model is constructed, taking into account the dynamic characteristics of the prime mover model, and simulating the transient dynamic process of the generator and its accessories;

[0011] Initialize the parameters of the generator body model and accessory model, calculate the swing angle through the terminal voltage and current, and input the parameter data structure;

[0012] The generator body and accessory models are solved jointly to perform transient simulation calculations. The simulation accuracy is dynamically adjusted by adjusting the order of the generator body model and selecting generator body models of different complexities.

[0013] Preferably, generator body models of different complexities are constructed, including a second-order classical generator model, a dual-axis fourth-order generator model without taking into account the damping winding, and a dual-axis sixth-order generator model taking into account the damping winding;

[0014] The second-order classical generator model only takes into account the rotor dynamics, ignoring the transient effects of the stator winding, and uses mechanical power input and electromagnetic power output to represent the dynamic behavior of the generator; the second-order classical generator model is as follows:

[0015]

[0016] Where:

[0017] u d and u q They represent the stator voltage components of the generator on the d-axis and q-axis, respectively, and are used to represent the transient response of the synchronous generator winding; E′d and E′ q Respectively represent the transient potential of the generator on the d-axis and q-axis; X′ q and X′ d are the transient reactances on the q-axis and d-axis, respectively, which are used to reflect the reactance characteristics of the stator winding of the generator during the transient process; r a It represents the resistance of the generator stator winding, which is used to reflect the power loss when the current flows through the stator winding; i d and i q The stator current components on the d-axis and q-axis are used to reflect the current changes of the stator winding during the transient process; T J represents the moment of inertia of the generator rotor; Indicates the rate of change of the rotor angular velocity; T m Represents the mechanical power input of the generator; T e represents the electromagnetic power output of the generator; D represents the damping coefficient of the generator; δ represents the rotor angle of the generator, which is used to describe the angular displacement of the generator rotor relative to the synchronous voltage; Δω represents the difference between the angular velocity of the rotor and the synchronous angular velocity; ω B represents the reference angular velocity of the generator;

[0018] The dual-axis fourth-order generator model without damping winding takes into account the rotor dynamics and rotor excitation winding, and does not take into account the transient effect of the stator winding; the rotor excitation winding includes the d-axis excitation winding on the rotor and the g-winding on the q-axis; the dual-axis fourth-order generator model without damping winding is as follows:

[0019]

[0020] Where:

[0021] T′ q0 and T′ d0 They represent the open circuit transient time constants of the q-axis and the d-axis respectively; E f Represents the excitation potential, which is used to control the output voltage and current of the generator;

[0022] The double-shaft sixth-order generator model including the damping winding is used to describe the subtransient behavior of the generator, including the subtransient reactance on the d-axis and q-axis; the double-shaft sixth-order generator model including the damping winding is as follows:

[0023]

[0024] Where:

[0025] E″ d and E″ q Respectively represent the sub-transient potential of the generator on the d-axis and q-axis; X″ q and X″ dare the subtransient reactances on the q-axis and d-axis respectively; T″ q and T″ d are the subtransient constants on the q-axis and d-axis respectively.

[0026] Preferably, according to the construction result of the generator body model, a generator accessory model matching the generator body model is constructed, taking into account the dynamic characteristics in the prime mover model, and simulating the transient dynamic process of the generator and its accessories; including:

[0027] According to the dynamic requirements of the generator, select the excitation model type that matches the generator body model, and define the input parameters of the excitation model, including the terminal voltage and reference voltage, to guide voltage regulation;

[0028] Construct and integrate the prime mover model to represent the output characteristics of the mechanical power of the generator in the transient dynamic process and simulate the dynamic conversion process between mechanical power and electrical power;

[0029] Based on the prime mover model, a speed regulator model is constructed to adjust the speed and load distribution of the generator set. The speed regulator model describes the dynamic changes of the prime mover speed through the transfer function and is closely integrated with the prime mover to make dynamic adjustments when the load changes.

[0030] The power system stabilizer PSS model is constructed to suppress frequency oscillation by providing additional excitation regulation signals when the frequency fluctuates, and the output signal for regulating the excitation potential is generated by using the slip and acceleration power as input voltages;

[0031] The excitation model, prime mover model, speed regulator model, power system stabilizer PSS model and generator body model are integrated to simulate the complete dynamic response of the generator and its accessories during transient processes.

[0032] Preferably, the excitation model types include continuous rotating DC excitation EA type and self-shunt static excitation FV type;

[0033] The continuous rotating DC excitation EA type generates excitation current through a mechanically driven DC generator. It is suitable for operating conditions where voltage is continuously regulated and meets the voltage regulation requirements caused by load changes and external conditions during generator operation.

[0034] The self-shunt static excitation FV type uses static power electronics to adjust the excitation current to cope with voltage changes.

[0035] Preferably, the prime mover includes a steam turbine and a water turbine;

[0036] The steam turbine drives the generator's prime mover by driving the turbine to rotate with steam. Taking into account the steam inertia, the relationship between steam flow and power output is expressed through the first-order inertia link, and the effect of the change in the valve opening on the speed and power is expressed to reflect the effect of the steam power of the steam turbine on the generator during the transient process.

[0037] The turbine drives the turbine blades to rotate through water flow. Taking into account the inertia of water flow, the relationship between the opening of the water guide vane and the power output is expressed through a dynamic equation, and the influence of the water hammer effect on the instantaneous pressure fluctuation is taken into account to reflect the change of water flow through the water guide vane adjustment to affect the power output of the generator;

[0038] The prime mover model and the generator body model are dynamically coupled to convert mechanical power and electrical power. During the integration process, the output power of the prime mover and the electromagnetic dynamic response of the generator run synchronously.

[0039] Preferably, the parameters of the generator body model and the accessory model are initialized, the swing angle is calculated by the terminal voltage and current, and the parameter data structure is input, as follows:

[0040] Before simulating the transient dynamic process of the generator and its accessories, the relevant parameters of the generator body model and the accessory model are initialized, including setting the initial states of the generator body model and the accessory model so that the parameters are consistent with the physical characteristics of the actual equipment;

[0041] Using the voltage and current data at the generator end, combined with the stator reactance, the initial swing angle of the generator is used to represent the relative angle of the generator rotor relative to the grid, and the swing angle δ is calculated as follows:

[0042]

[0043] Where:

[0044] i q and i d represents the current components on the q-axis and d-axis;

[0045] All initialized parameters and calculated swing angles are input into the parameter data structure that simulates the transient dynamics of the generator and its accessories, and all key parameters related to the generator and its accessories model are organized and stored, including rotor angle, speed, mechanical power, voltage, current and excitation potential.

[0046] Preferably, the initial swing angle is as follows:

[0047] In the initialization stage, the terminal voltage is Current and stator reactance x q , determine the virtual potential E QThe angle is used to represent the position of the q-axis in the dq coordinate system, and the virtual potential is calculated as follows:

[0048]

[0049] Where:

[0050] U x , U y ,I x ,I y is the voltage and current decomposed into x and y axes.

[0051] Preferably, the generator body and accessory models are solved jointly to perform transient simulation calculations. By adjusting the order of the generator body model and selecting generator body models of different complexities, the simulation accuracy is dynamically adjusted, as follows:

[0052] Solve the generator body model and accessory model simultaneously, and process the dynamic response of the generator and its accessories in the transient process, so that the electrical and mechanical parts can operate synchronously;

[0053] Transient simulation is performed through the combined generator body and accessory models. During the simulation process, the order of the generator body model is adjusted in real time to cope with transient response requirements of different complexities, taking into account the dynamic changes of simulated voltage, current and speed, so that the simulation results are consistent with the actual operating status.

[0054] Preferably, in transient simulation, the transfer functions of the generator body model and the accessory model are converted into differential equations, and all differential equations are converted into differential equations through difference processing to meet the needs of discretization simulation; the simultaneous solution equations are calculated as follows:

[0055] Δh g +Δh a =J k Δy g +Δy a

[0056] Where:

[0057] h g and h a Respectively represent the status of the generator body and accessory model;

[0058] J k is the Jacobian matrix, as follows:

[0059]

[0060] The numerical iteration method is used to solve and calculate the dynamic response of the generator, including the changing parameters of the swing angle, voltage and speed; at each iteration, the Jacobian matrix is ​​updated and the numerical value of the next step is calculated until the set simulation accuracy is reached.

[0061] A second aspect of the present invention provides a generator body for transient calculation, comprising: a generator rotor model, a stator winding, an excitation model interface, transient reactance and capacitance elements, and a data acquisition and control interface;

[0062] The generator rotor model is used to store and release mechanical energy in transient processes. The relative motion between the rotor and the stator generates electromotive force, and its characteristics reflect the dynamic response of the generator in the power grid.

[0063] The stator winding generates three-phase alternating current through interaction with the rotor magnetic field, and the winding reactance effect in transient state is not taken into account to simplify the electrical characteristics in transient simulation calculation;

[0064] The excitation model interface connects the generator body to the excitation model and controls the voltage output of the generator through the external excitation model;

[0065] Transient reactance and capacitance elements are used to represent the electrical characteristics of the generator during transient processes. They are used to adjust the dynamics of current and voltage to reflect the electromagnetic behavior of the generator in transient response;

[0066] The data acquisition and control interface is used to monitor the operating status of the generator in real time, including key parameters such as voltage, current and speed. Through the control interface, the generator is linked with external control for dynamic adjustment.

[0067] Compared with the prior art, the beneficial effects of the present invention include at least:

[0068] (1) By constructing generator models of different complexity, including second-order, fourth-order and sixth-order models, the simulation modeling process of complex systems is effectively simplified. According to different simulation requirements, selecting the appropriate model order can not only ensure the accuracy of the simulation, but also improve the efficiency of the simulation calculation;

[0069] (2) By dynamically adjusting the order of the generator model during the simulation process, from the second-order classical model to the more complex dual-axis sixth-order model, the simulation accuracy and computational efficiency are balanced. By adjusting the model order in real time, it can adapt to different transient response requirements and ensure that high simulation accuracy can be maintained under highly complex transient conditions.

[0070] (3) By initializing parameters and calculating the swing angle, it can respond quickly during the simulation startup phase. The input parameter data structure ensures efficient management and call of data during the simulation process, improves the real-time performance of the simulation, and enables the system to respond quickly to transient disturbances. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 is an initial swing angle δ diagram provided according to an embodiment of the present invention;

[0072] Figure 2 is a transfer function block diagram of an EA type excitation regulator provided according to an embodiment of the present invention;

[0073] Figure 3 is a transfer function diagram of a self-shunt excited static excitation system provided according to an embodiment of the present invention;

[0074] Figure 4 is a FU-type transfer function diagram of a rotating excitation system provided in accordance with an embodiment of the present invention;

[0075] Figure 5 It is a schematic diagram of a rotating excitation system (brush, brushless) FQ, FR type provided according to an embodiment of the present invention;

[0076] Figure 6 It is a schematic diagram of a rotating excitation system (brush, brushless) F0, FP type provided according to an embodiment of the present invention;

[0077] Figure 7 It is a schematic diagram of a rotating excitation system FM and FN type provided according to an embodiment of the present invention;

[0078] Figure 8 is a schematic diagram of FQ and FR type transfer functions of a rotating excitation system provided according to an embodiment of the present invention;

[0079] Fig. 9 It is a transfer function diagram of FS and FT type of the rotating excitation system provided according to the embodiment of the present invention;

[0080] Fig.10 It is a structural diagram of the IEEE-GH turbine and speed control system model provided according to an embodiment of the present invention;

[0081] Fig.11 It is a structural diagram of an IEEE GS+TB steam turbine and speed control system model provided according to an embodiment of the present invention;

[0082] Fig.12 It is a structural diagram of the IEEEGL+TB model provided according to an embodiment of the present invention;

[0083] Fig.13 It is a structural diagram of the GI+GA+TB model provided according to an embodiment of the present invention;

[0084] Fig.14 It is a diagram of an SS model and an SP model provided according to an embodiment of the present invention;

[0085] Fig.15 is a SH model diagram provided according to an embodiment of the present invention;

[0086] Fig.16 is a SI / SI+ model diagram provided according to an embodiment of the present invention;

[0087] Fig.17 is a flow chart of a data input method provided according to an embodiment of the present invention;

[0088] Fig.18 It is a structural diagram of a GW+TW model provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0089] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described in this application are only part of the embodiments of the present invention, not all of them. Based on the spirit of the present invention, other embodiments obtained by ordinary technicians in this field without creative work are all within the scope of protection of the present invention.

[0090] like Fig.17 As shown, Example 1 of the present invention provides a simulation modeling method for a generator body and its accessories for transient calculation, comprising the following steps:

[0091] Construct generator models of different complexity and simplify the generator models according to simulation requirements;

[0092] Preferably, generator body models of different complexities are constructed, including a second-order classical generator model, a dual-axis fourth-order generator model without taking into account the damping winding, and a dual-axis sixth-order generator model taking into account the damping winding;

[0093] The second-order classical generator model only takes into account the rotor dynamics, ignoring the transient effects of the stator winding, and uses mechanical power input and electromagnetic power output to represent the dynamic behavior of the generator; the second-order classical generator model is as follows:

[0094]

[0095] Where:

[0096] u d and u q They represent the stator voltage components of the generator on the d-axis and q-axis, respectively, and are used to represent the transient response of the synchronous generator winding; E′ d and E′ q Respectively represent the transient potential of the generator on the d-axis and q-axis; X′ q and X′ dare the transient reactances on the q-axis and d-axis, respectively, which are used to reflect the reactance characteristics of the stator winding of the generator during the transient process; r a It represents the resistance of the generator stator winding, which is used to reflect the power loss when the current flows through the stator winding; i q and i q The stator current components on the d-axis and q-axis are used to reflect the current changes of the stator winding during the transient process; T J represents the moment of inertia of the generator rotor; Indicates the rate of change of the rotor angular velocity; T m Represents the mechanical power input of the generator; T e represents the electromagnetic power output of the generator; D represents the damping coefficient of the generator; δ represents the rotor angle of the generator, which is used to describe the angular displacement of the generator rotor relative to the synchronous voltage; Δω represents the difference between the angular velocity of the rotor and the synchronous angular velocity; ω B represents the reference angular velocity of the generator;

[0097] Furthermore, this is a second-order model that only considers rotor dynamics. d '≠x q ', that is, the transient salient effect is still taken into account, but it is assumed that E q ′=const,E d '=const. This is consistent with the physical phenomenon that the rotor winding flux remains unchanged at the moment of short circuit. Therefore, this model is only applicable to short circuit current calculation.

[0098] The dual-axis fourth-order generator model without damping winding takes into account the rotor dynamics and rotor excitation winding, and does not take into account the transient effect of the stator winding; the rotor excitation winding includes the d-axis excitation winding on the rotor and the g-winding on the q-axis; the dual-axis fourth-order generator model without damping winding is as follows:

[0099]

[0100] Where:

[0101] T′ q0 and T′ d0 They represent the open circuit transient time constants of the q-axis and the d-axis respectively; E f Represents the excitation potential, which is used to control the output voltage and current of the generator;

[0102] Furthermore, in addition to ignoring stator transients and ω≈1, the derivation of this model also ignores the DQ damping winding on the rotor, whose effect can be approximated by adding the damping term to the rotor motion equation. However, the d-axis excitation winding and the q-axis g winding are considered.

[0103] The double-shaft sixth-order generator model including the damping winding is used to describe the subtransient behavior of the generator, including the subtransient reactance on the d-axis and q-axis; the double-shaft sixth-order generator model including the damping winding is as follows:

[0104]

[0105] Where:

[0106] E″ d and E″ q Respectively represent the sub-transient potential of the generator on the d-axis and q-axis; X″ q and X″ d are the subtransient reactances on the q-axis and d-axis respectively; T″ q and T″ d are the subtransient constants on the q-axis and d-axis respectively.

[0107] Furthermore, the sub-transient and transient electromagnetic processes of the excitation winding f and the damping winding D of the generator rotor d axis in the model are represented by E″ q and E′ q The q-axis considers the sub-transient and transient electromagnetic processes of the damping windings Q and g, which are represented by the potential changes of Ed” and Ed’ respectively. The electromagnetic transient process of the q-axis damping winding g only needs to be considered in the case of a hidden pole machine to describe the physical nature of the hidden pole rotor with large equivalent damping inductance and time constant and strong damping of the corresponding transient process.

[0108] The generator body data structure is as follows:

[0109] The key parameters of the generator in the simulation model and their meanings are described. ID is used to identify different generators, while XD and XQ represent the synchronous reactance of the generator in the direct and quadrature directions, respectively, reflecting the reactance characteristics of the generator in different axial directions. TDD and TQQ represent the transient time constants of the generator in the direct and quadrature directions, respectively, defining the speed at which the generator responds during transient processes. Similarly, TD and TQ represent the subtransient time constants of the direct and quadrature axes, respectively, and are used to describe the dynamic response characteristics of the subtransient stage. The D coefficient of the generator represents the damping coefficient, which is used to measure the damping effect during mechanical oscillation. In addition, XDP and XDPP represent the transient and subtransient reactances of the direct axis, respectively, and XQP represents the transient reactance of the quadrature axis. These parameters together define the reactance behavior of the generator in different transient and subtransient stages. Through these parameters, the electromagnetic characteristics and dynamic response of the generator under different operating conditions can be fully described.

[0110] Based on the above mathematical model, the data structure of the generator body is established as follows:

[0111] Table 1: Generator ontology data structure keyword correspondence table

[0112] Keywords meaning ID Generator ID XD Generator direct-axis synchronous reactance XQ Generator quadrature-axis synchronous reactance TDD Generator direct axis transient time constant TQQ Generator direct axis transient time constant TD Generator direct-axis subtransient time constant TQ Generator quadrature-axis subtransient time constant D Generator damping factor XDP Generator direct axis transient reactance XDPP Generator direct-axis subtransient reactance XQP Generator quadrature axis transient reactance QX Generator quadrature-axis subtransient reactance M Generator rotor inertia constant CODE Generator No. NAME Generator Name

[0113] According to the calculation accuracy requirements, the corresponding generator model can be selected to participate in the transient calculation.

[0114] According to Table 1, the generator body data structure is established, where " <dsync> ”、"< / dsync> " are the start and end identification codes of a record respectively:

[0115]

[0116] According to the construction results of the generator body model, a generator accessory model matching the generator body model is constructed, taking into account the dynamic characteristics of the prime mover model, and simulating the transient dynamic process of the generator and its accessories;

[0117] like Figures 1 to 9 As shown, preferably, according to the construction result of the generator body model, a generator accessory model matching the generator body model is constructed, the dynamic characteristics in the prime mover model are taken into account, and the transient dynamic process of the generator and its accessories is simulated; including:

[0118] According to the dynamic requirements of the generator, select the excitation model type that matches the generator body model, and define the input parameters of the excitation model, including the terminal voltage and reference voltage, to guide voltage regulation;

[0119] like Figures 10 to 16 As shown, a prime mover model is constructed and integrated to represent the output characteristics of the mechanical power of the generator in the transient dynamic process and simulate the dynamic conversion process between mechanical power and electrical power;

[0120] Based on the prime mover model, a speed regulator model is constructed to adjust the speed and load distribution of the generator set. The speed regulator model describes the dynamic changes of the prime mover speed through the transfer function and is closely integrated with the prime mover to make dynamic adjustments when the load changes.

[0121] The power system stabilizer PSS model is constructed to suppress frequency oscillation by providing additional excitation regulation signals when the frequency fluctuates, and the output signal for regulating the excitation potential is generated by using the slip and acceleration power as input voltages;

[0122] Preferably, the present invention is currently capable of simulating four PSS models: an SS model with shaft slip as an input signal, an SP model with acceleration power as an input signal, an SH model, and an SI / SI+ model.

[0123] like Fig.14As shown in the figure, the transfer function of the SS model is the same as that of the SP model, except that in the SP model, the reference capacity of the control gain KQS is the reference capacity of the motor per unit parameter of the generator. First, a signal is selected from the input signals such as shaft slip, frequency deviation or acceleration power for adjustment. Then, the signal is gradually smoothed through gain amplification and multiple time constant links to remove fluctuations in the signal. Finally, the adjusted signal passes through an output limiter to ensure that the output voltage regulation signal is between the set upper and lower limits. Through this process, the PSS can adjust the output voltage of the generator, maintain the stability of the power system, and avoid instability caused by load fluctuations or interference.

[0124] like Fig.15 As shown in the SH model, first, the system receives the input power signal P G and reference power P G0 The difference between the two is passed through the gain amplifier K P and time constant T D After adjustment, it enters the feedback control link. There are multiple time constant modules (T1, T2, T3) in the system, which are combined with gain coefficients K0, K1, K2, K3 respectively to gradually smooth and adjust the signal. Finally, the signal is adjusted through the amplifier KKK to adjust the power output, and the output signal is limited to the upper and lower limits V Smax and V Smin This process ensures smooth regulation of system power and stability of output.

[0125] like Fig.16 As shown in Figure 1, the input of the SI / SI+ PSS model includes the angular velocity deviation and power deviation of the generator and the reference power. The angular velocity signal passes through multiple time constant adjustment modules, is gradually processed, and enters the adjustment link after gain synthesis. The power deviation signal is also adjusted by multiple time constants and gain modules. Finally, the two signals converge, and after a series of phase shift links and gain adjustments, the voltage adjustment signal is output, and the output voltage is ensured to be within V by the limiter. Smax and V Smin This process ensures smooth regulation of system power and stability of output.

[0126] The generator accessory data structure is as follows:

[0127] The following uses PSS (power system stabilizer) as an example to illustrate the data structure of the generator accessory model data file, where ID represents the identification code of PSS, CODE is the number of PSS, TYPE and SUBTYPE represent the type and subtype of PSS respectively. TRW represents the time constant of speed measurement, while T5 to T6 are the time constants of the phase shift link, which are used for different phase shift adjustments respectively. T7 is the time constant of the speed isolation link. KR represents the amplification factor of the power deviation, and TRP is the time constant of the power measurement. TW, TW1 and TW2 are the time constants of the power isolation link, which are used to handle the dynamic response when the power changes. KS is the compensation coefficient of the power deviation, and T9 and T10 are the notch filter time constants, which are used to filter out fluctuations of specific frequencies. KW and KP are the amplification factors of the speed deviation and power deviation respectively, while T1 to T4 are the time constants of different phase shift links. VSMAX and VSMIN define the upper and lower limits of the PSS output, and finally, NOTE is used to record the note information. As shown in Table 2:

[0128] Table 2: PSS data structure keyword correspondence table

[0129]

[0130]

[0131] The generator accessory model data structure is established according to Table 2. The following is a detailed display of a record in a model parameter file of a PSS mentioned in the technical solution, where " <dpss> ”、"< / dpss> " are the start and end identification codes of a record respectively, and the remaining keywords correspond to the keywords according to the PSS model parameters listed in Table 4:

[0132]

[0133]

[0134] The matching method of the generator body and its accessories is as follows:

[0135] A data structure representing the association between the generator body and its accessory models is established. For each generator body, its basic information and the model type of each accessory device are first matched. If there are new generator accessory models, they are also added to this data structure.

[0136] The data structure of the association between the generator body and its accessory models is as follows in Table 3:

[0137] Table 3: Keyword correspondence table of the relationship between the generator body and its accessory models

[0138]

[0139]

[0140] In the above data structure, the accuracy of the mathematical model of the generator body can be adjusted by adjusting the parameters of "DYNMDL", and different types of generator accessories can be selected by adjusting parameters such as "EXCID", "PSSID", "GOVID", and "TURID" to achieve better transient calculation results.

[0141] According to Table 3, the relationship between the generator body and its accessory models is established. The following are the detailed parameters of a unit, where "<DUN_DYN> ","< / DUN_DYN> " are the start and end identification codes of a record respectively

[0142]

[0143] The excitation model, prime mover model, speed regulator model, power system stabilizer PSS model and generator body model are integrated to simulate the complete dynamic response of the generator and its accessories during transient processes.

[0144] Preferably, the excitation model types include but are not limited to the continuous rotating DC excitation EA type and the self-parallel excitation static excitation FV type;

[0145] The continuous rotating DC excitation EA type generates excitation current through a mechanically driven DC generator. It is suitable for operating conditions where voltage is continuously regulated and meets the voltage regulation requirements caused by load changes and external conditions during generator operation.

[0146] The self-shunt static excitation FV type uses static power electronics to adjust the excitation current to cope with voltage changes.

[0147] Preferably, the excitation model type also includes a rotating excitation model FU type which is a system for adjusting the excitation current by rotating the motor;

[0148] Rotating excitation model (brush or brushless) FQ and FR are brush and brushless rotating excitation models respectively, suitable for the design requirements of different generators;

[0149] The rotating excitation model F0 and FP are also a type of rotating excitation system, suitable for specific application scenarios;

[0150] Rotating excitation model FM and FN are another type of rotating excitation system, which can provide precise excitation control for the generator;

[0151] The rotating excitation models FQ and FR provide brushed or brushless rotating excitation modes, which can be flexibly applied to different designs of generators.

[0152] Rotating excitation system FS, FT type

[0153] FS and FT type rotating excitation systems have unique transfer functions and are applied to specific types of generators.

[0154] Preferably, the prime mover includes a steam turbine and a water turbine;

[0155] The dynamic characteristics of a steam turbine mainly consider the steam volume effect, that is, due to the steam inertia between the valve and the nozzle, the steam pressure will not change immediately, resulting in the input power of the steam turbine will not change immediately. Usually, this phenomenon can be simulated by the first-order inertia link. The mathematical model of a steam turbine describes the relationship between the valve opening and the output mechanical power.

[0156] Similarly, the dynamic characteristics of a turbine mainly consider the water hammer effect. The inertia of the water flow causes the change in the opening of the water guide vanes to cause the change in the instantaneous power of the turbine. When the water guide vanes are suddenly opened, the instantaneous power of the turbine will suddenly decrease and then increase, and vice versa. The mathematical model of the turbine is used to describe the relationship between the opening of the water guide vanes and the output mechanical power.

[0157] The speed control system is an important part of the prime mover. Its main function is to automatically maintain the speed of the unit and distribute the load between the units. The speed control system of the steam turbine includes a hydraulic speed governor and a power frequency electro-hydraulic speed governor. These two types of speed governors can be described by the same mathematical model. The speed control system of the water turbine includes a mechanical speed governor and an electrical hydraulic speed governor, which can also be simulated by the same mathematical model.

[0158] In the present invention, the speed control system model of the water turbine includes the GH model and the GW+TW model, while the speed control system model of the steam turbine includes the GS+TB model, the GL+TB model and the GI+GA+TB model. These models are used to simulate the power frequency regulation process of different types of steam turbines and water turbine speed regulators and prime mover combinations.

[0159] like Fig.10 As shown in the figure, the GH model is used to simulate the turbine governor of a hydropower plant, and the power and frequency are regulated by controlling the opening of the guide vanes.

[0160] like Fig.12 As shown in Figure 1, the GS+TB model is used to simulate the turbine governor of a thermal power plant and describes the relationship between the valve opening and the output mechanical power.

[0161] The GI+GA+TB model is a combination of turbine speed control systems, which is suitable for complex regulation requirements. Initialize the parameters of the generator body model and accessory model, calculate the swing angle through the terminal voltage and current, and input the parameter data structure;

[0162] Preferably, the parameters of the generator body model and the accessory model are initialized, the swing angle is calculated by the terminal voltage and current, and the parameter data structure is input, as follows:

[0163] Before simulating the transient dynamic process of the generator and its accessories, the relevant parameters of the generator body model and the accessory model are initialized, including setting the initial states of the generator body model and the accessory model so that the parameters are consistent with the physical characteristics of the actual equipment;

[0164] Using the voltage and current data at the generator end, combined with the stator reactance, the initial swing angle of the generator is used to represent the relative angle of the generator rotor relative to the grid, and the swing angle δ is calculated as follows:

[0165]

[0166] Where:

[0167] i q and i d represents the current components on the q-axis and d-axis;

[0168] All initialized parameters and calculated swing angles are input into the parameter data structure that simulates the transient dynamics of the generator and its accessories, and all key parameters related to the generator and its accessories model are organized and stored, including rotor angle, speed, mechanical power, voltage, current and excitation potential.

[0169] Preferably, if Figure 1 As shown, the initial swing angle is as follows:

[0170] In the initialization stage, the terminal voltage is Current and stator reactance x q , determine the virtual potential E Q The angle is used to represent the position of the q-axis in the dq coordinate system, and the virtual potential is calculated as follows:

[0171]

[0172] Where:

[0173] U x , U y ,I x ,I y is the voltage and current decomposed into x and y axes.

[0174] The generator body and accessory models are solved jointly to perform transient simulation calculations. The simulation accuracy is dynamically adjusted by adjusting the order of the generator body model and selecting generator body models of different complexities.

[0175] Preferably, the generator body and accessory models are solved jointly to perform transient simulation calculations. By adjusting the order of the generator body model and selecting generator body models of different complexities, the simulation accuracy is dynamically adjusted, as follows:

[0176] Solve the generator body model and accessory model simultaneously, and process the dynamic response of the generator and its accessories in the transient process, so that the electrical and mechanical parts can operate synchronously;

[0177] Transient simulation is performed through the combined generator body and accessory models. During the simulation process, the order of the generator body model is adjusted in real time to cope with transient response requirements of different complexities, taking into account the dynamic changes of simulated voltage, current and speed, so that the simulation results are consistent with the actual operating status.

[0178] Preferably, in transient simulation, the transfer functions of the generator body model and the accessory model are converted into differential equations, and all differential equations are converted into differential equations through difference processing to meet the needs of discretization simulation; the simultaneous solution equations are calculated as follows:

[0179] Δh g +Δh a =J k Δy g +Δy a

[0180] Where:

[0181] h g and h a Respectively represent the status of the generator body and accessory model;

[0182] J k is the Jacobian matrix, as follows:

[0183]

[0184] The numerical iteration method is used to solve and calculate the dynamic response of the generator, including the changing parameters of the swing angle, voltage and speed; at each iteration, the Jacobian matrix is ​​updated and the numerical value of the next step is calculated until the set simulation accuracy is reached.

[0185] Solve the model parameter equations and system equations simultaneously. If this generator is the kth generator, the unit body and accessories are represented by subscripts g and a respectively.

[0186]

[0187] Then the iterative equation can be written as:

[0188] in

[0189]

[0190] For the second-order generator model, there are 4 state variables and its Jacobian matrix is ​​4x4.

[0191] Some code implementations are as follows:

[0192]

[0193]

[0194]

[0195]

[0196]

[0197] Example 2 of the present invention provides a generator body for transient calculation, including: a generator rotor model, a stator winding, an excitation model interface, transient reactance and capacitance elements, and a data acquisition and control interface;

[0198] The generator rotor model is used to store and release mechanical energy in transient processes. The relative motion between the rotor and the stator generates electromotive force, and its characteristics reflect the dynamic response of the generator in the power grid.

[0199] The stator winding generates three-phase alternating current through interaction with the rotor magnetic field, and the winding reactance effect in transient state is not taken into account to simplify the electrical characteristics in transient simulation calculation;

[0200] The excitation model interface connects the generator body to the excitation model and controls the voltage output of the generator through the external excitation model;

[0201] The rotating excitation model F0 and FP are also a type of rotating excitation system, suitable for specific application scenarios;

[0202] Rotating excitation model FM and FN are another type of rotating excitation system, which can provide precise excitation control for the generator; The rotating excitation models FQ and FR provide brushed or brushless rotating excitation modes, which can be flexibly applied to different designs of generators. Rotating excitation system FS, FT type FS and FT type rotating excitation systems have unique transfer functions and are applied to specific types of generators. Preferably, the prime mover includes a steam turbine and a water turbine; The dynamic characteristics of a steam turbine mainly consider the steam volume effect, that is, due to the steam inertia between the valve and the nozzle, the steam pressure will not change immediately, resulting in the input power of the steam turbine will not change immediately. Usually, this phenomenon can be simulated by the first-order inertia link. The mathematical model of a steam turbine describes the relationship between the valve opening and the output mechanical power. Similarly, the dynamic characteristics of a turbine mainly consider the water hammer effect. The inertia of the water flow causes the change in the opening of the water guide vanes to cause the change in the instantaneous power of the turbine. When the water guide vanes are suddenly opened, the instantaneous power of the turbine will suddenly decrease and then increase, and vice versa. The mathematical model of the turbine is used to describe the relationship between the opening of the water guide vanes and the output mechanical power. The speed control system is an important part of the prime mover. Its main function is to automatically maintain the speed of the unit and distribute the load between the units. The speed control system of the steam turbine includes a hydraulic speed governor and a power frequency electro-hydraulic speed governor. These two types of speed governors can be described by the same mathematical model. The speed control system of the water turbine includes a mechanical speed governor and an electrical hydraulic speed governor, which can also be simulated by the same mathematical model. In the present invention, the speed control system model of the water turbine includes the GH model and the GW+TW model, while the speed control system model of the steam turbine includes the GS+TB model, the GL+TB model and the GI+GA+TB model. These models are used to simulate the power frequency regulation process of different types of steam turbines and water turbine speed regulators and prime mover combinations. The GH model is used to simulate the turbine governor of a hydropower plant, and adjusts the power and frequency by controlling the opening of the guide vanes. The GS+TB model is used to simulate the turbine governor of a thermal power plant and describes the relationship between the valve opening and the output mechanical power. The GI+GA+TB model is a combination of turbine speed control systems, which is suitable for complex regulation requirements. Initialize the parameters of the generator body model and accessory model, calculate the swing angle through the terminal voltage and current, and input the parameter data structure; Preferably, the parameters of the generator body model and the accessory model are initialized, the swing angle is calculated by the terminal voltage and current, and the parameter data structure is input, as follows: Before simulating the transient dynamic process of the generator and its accessories, the relevant parameters of the generator body model and the accessory model are initialized, including setting the initial states of the generator body model and the accessory model so that the parameters are consistent with the physical characteristics of the actual equipment; Using the voltage and current data at the generator end, combined with the stator reactance, the initial swing angle of the generator is used to represent the relative angle of the generator rotor relative to the grid, and the swing angle δ is calculated as follows: Where: i q and i d represents the current components on the q-axis and d-axis; All initialized parameters and calculated swing angles are input into the parameter data structure that simulates the transient dynamics of the generator and its accessories, and all key parameters related to the generator and its accessories model are organized and stored, including rotor angle, speed, mechanical power, voltage, current and excitation potential. Preferably, if Figure 2 As shown, the initial swing angle is as follows: In the initialization stage, the terminal voltage is Current and stator reactance x q , determine the virtual potential E Q The angle is used to represent the position of the q-axis in the dq coordinate system, and the virtual potential is calculated as follows: Where: U x , U y ,I x ,I y is the voltage and current decomposed into x and y axes. The generator body and accessory models are solved jointly to perform transient simulation calculations. The simulation accuracy is dynamically adjusted by adjusting the order of the generator body model and selecting generator body models of different complexities. Preferably, the generator body and accessory models are solved jointly to perform transient simulation calculations. By adjusting the order of the generator body model and selecting generator body models of different complexities, the simulation accuracy is dynamically adjusted, as follows: Solve the generator body model and accessory model simultaneously, and process the dynamic response of the generator and its accessories in the transient process, so that the electrical and mechanical parts can operate synchronously; Transient simulation is performed through the combined generator body and accessory models. During the simulation process, the order of the generator body model is adjusted in real time to cope with transient response requirements of different complexities, taking into account the dynamic changes of simulated voltage, current and speed, so that the simulation results are consistent with the actual operating status. Preferably, in transient simulation, the transfer functions of the generator body model and the accessory model are converted into differential equations, and all differential equations are converted into differential equations through difference processing to meet the needs of discretization simulation; the simultaneous solution equations are calculated as follows: Δh g +Δh a =J k Δy g +Δya Where: h g and h a Respectively represent the status of the generator body and accessory model; J k is the Jacobian matrix, as follows: The numerical iteration method is used to solve and calculate the dynamic response of the generator, including the changing parameters of the swing angle, voltage and speed; at each iteration, the Jacobian matrix is ​​updated and the numerical value of the next step is calculated until the set simulation accuracy is reached. Solve the model parameter equations and system equations simultaneously. If this generator is the kth generator, the unit body and accessories are represented by subscripts g and a respectively. Then the iterative equation can be written as: in For the second-order generator model, there are 4 state variables and its Jacobian matrix is ​​4x4. Some code implementations are as follows: Example 2 of the present invention provides a generator body for transient calculation, including: a generator rotor model, a stator winding, an excitation model interface, transient reactance and capacitance elements, and a data acquisition and control interface; The generator rotor model is used to store and release mechanical energy in transient processes. The relative motion between the rotor and the stator generates electromotive force, and its characteristics reflect the dynamic response of the generator in the power grid. The stator winding generates three-phase alternating current through interaction with the rotor magnetic field, and the winding reactance effect in transient state is not taken into account to simplify the electrical characteristics in transient simulation calculation; The excitation model interface connects the generator body to the excitation model and controls the voltage output of the generator through the external excitation model; Transient reactance and capacitance elements are used to represent the electrical characteristics of the generator during transient processes. They are used to adjust the dynamics of current and voltage to reflect the electromagnetic behavior of the generator in transient response; The data acquisition and control interface is used to monitor the operating status of the generator in real time, including key parameters such as voltage, current and speed. Through the control interface, the generator is linked with external control for dynamic adjustment.

[0203] The beneficial effects of the present invention include at least:

[0204] (1) By constructing generator models of different complexity, including second-order, fourth-order and sixth-order models, the simulation modeling process of complex systems is effectively simplified. According to different simulation requirements, selecting the appropriate model order can not only ensure the accuracy of the simulation, but also improve the efficiency of the simulation calculation;

[0205] (2) By dynamically adjusting the order of the generator model during the simulation process, from the second-order classical model to the more complex dual-axis sixth-order model, the simulation accuracy and computational efficiency are balanced. By adjusting the model order in real time, it can adapt to different transient response requirements and ensure that high simulation accuracy can be maintained under highly complex transient conditions.

[0206] (3) By initializing parameters and calculating the swing angle, it can respond quickly during the simulation startup phase. The input parameter data structure ensures efficient management and call of data during the simulation process, improves the real-time performance of the simulation, and enables the system to respond quickly to transient disturbances.

[0207] The present disclosure may be a system, a method and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for causing a processor to implement various aspects of the present disclosure.

[0208] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A simulation modeling method for a generator body and its accessories for transient calculation, characterized in that: The following steps are involved: Construct generator models of different complexity and simplify the generator models according to simulation requirements; Based on the simplified generator model, a generator accessory model matching the generator body model is constructed, taking into account the dynamic characteristics of the prime mover model, and simulating the transient dynamic process of the generator and its accessories; Initialize the parameters of the generator body model and the accessory model, calculate the swing angle according to the terminal voltage and current, use the calculated swing angle as an input parameter and store it in the parameter data structure of the generator model; The generator body and accessory models are solved jointly to perform transient simulation calculations. The simulation accuracy is dynamically adjusted by adjusting the order of the generator body model and selecting generator body models of different complexities.

2. A simulation modeling method for transient calculation according to claim 1, characterized in that: Construct generator models of different complexity, including a second-order classical generator model, a dual-axis fourth-order generator model without damping winding, and a dual-axis sixth-order generator model with damping winding; The second-order classical generator model only takes into account the rotor dynamics, ignoring the transient effects of the stator winding, and uses mechanical power input and electromagnetic power output to represent the dynamic behavior of the generator; the second-order classical generator model is as follows: Where: u d and u q They represent the stator voltage components of the generator on the d-axis and q-axis, respectively, and are used to represent the transient response of the synchronous generator winding; E′ d and E′ q Respectively represent the transient potential of the generator on the d-axis and q-axis; X′ q and X′ d are the transient reactances on the q-axis and d-axis, respectively, which are used to reflect the reactance characteristics of the stator winding of the generator during the transient process; r a It represents the resistance of the generator stator winding, which is used to reflect the power loss when the current flows through the stator winding; i d and i q The stator current components on the d-axis and q-axis are used to reflect the current changes of the stator winding during the transient process; T J represents the moment of inertia of the generator rotor; Indicates the rate of change of the rotor angular velocity; T m Represents the mechanical power input of the generator; T e represents the electromagnetic power output of the generator; D represents the damping coefficient of the generator; δ represents the rotor angle of the generator, which is used to describe the angular displacement of the generator rotor relative to the synchronous voltage; Δω represents the difference between the angular velocity of the rotor and the synchronous angular velocity; ω B represents the reference angular velocity of the generator; The dual-axis fourth-order generator model without damping winding takes into account the rotor dynamics and rotor excitation winding, and does not take into account the transient effect of the stator winding; the rotor excitation winding includes the d-axis excitation winding on the rotor and the g-winding on the q-axis; the dual-axis fourth-order generator model without damping winding is as follows: Where: T′ q0 and T′ d0 They represent the open circuit transient time constants of the q-axis and the d-axis respectively; E f Represents the excitation potential, which is used to control the output voltage and current of the generator; The double-shaft sixth-order generator model including the damping winding is used to describe the subtransient behavior of the generator, including the subtransient reactance on the d-axis and q-axis; the double-shaft sixth-order generator model including the damping winding is as follows: Where: E″ d and E″ q Respectively represent the sub-transient potential of the generator on the d-axis and q-axis; X″ d and X″ d are the subtransient reactances on the q-axis and d-axis respectively; T″ q and T″ d are the subtransient constants on the q-axis and d-axis respectively.

3. The simulation modeling method for transient calculation according to claim 1, characterized in that: According to the construction results of the generator body model, a generator accessory model matching the generator body model is constructed, taking into account the dynamic characteristics of the prime mover model, and simulating the transient dynamic process of the generator and its accessories; including: According to the dynamic requirements of the generator, select the excitation model type that matches the generator body model, and define the input parameters of the excitation model, including the terminal voltage and reference voltage, to guide voltage regulation; Construct and integrate the prime mover model to represent the output characteristics of the mechanical power of the generator in the transient dynamic process and simulate the dynamic conversion process between mechanical power and electrical power; Based on the prime mover model, a speed regulator model is constructed to adjust the speed and load distribution of the generator set. The speed regulator model describes the dynamic changes of the prime mover speed through the transfer function and is closely integrated with the prime mover to make dynamic adjustments when the load changes. The power system stabilizer PSS model is constructed to suppress frequency oscillation by providing additional excitation regulation signals when the frequency fluctuates, and the output signal for regulating the excitation potential is generated by using the slip and acceleration power as input voltages; The excitation model, prime mover model, speed regulator model, power system stabilizer PSS model and generator body model are integrated to simulate the complete dynamic response of the generator and its accessories during transient processes.

4. A simulation modeling method for transient calculation according to claim 3, characterized in that: Excitation model types include continuous rotating DC excitation EA type and self-shunt static excitation FV type; The continuous rotating DC excitation EA type generates excitation current through a mechanically driven DC generator. It is suitable for operating conditions where voltage is continuously regulated and meets the voltage regulation requirements caused by load changes and external conditions during generator operation. The self-shunt static excitation FV type uses static power electronics to adjust the excitation current to cope with voltage changes.

5. The simulation modeling method for transient calculation according to claim 3, characterized in that: The prime movers include steam turbines and water turbines; The steam turbine drives the generator's prime mover by driving the turbine to rotate with steam. Taking into account the steam inertia, the relationship between steam flow and power output is expressed through the first-order inertia link, and the effect of the change in the valve opening on the speed and power is expressed to reflect the effect of the steam power of the steam turbine on the generator during the transient process. The turbine drives the turbine blades to rotate through water flow. Taking into account the inertia of water flow, the relationship between the opening of the water guide vane and the power output is expressed through a dynamic equation, and the influence of the water hammer effect on the instantaneous pressure fluctuation is taken into account to reflect the change of water flow through the water guide vane adjustment to affect the power output of the generator; The prime mover model and the generator body model are dynamically coupled to convert mechanical power and electrical power. During the integration process, the output power of the prime mover and the electromagnetic dynamic response of the generator run synchronously.

6. The simulation modeling method for transient calculation according to claim 1, characterized in that: Initialize the parameters of the generator body model and accessory model, calculate the swing angle through the terminal voltage and current, and input the parameter data structure, as follows: Before simulating the transient dynamic process of the generator and its accessories, the relevant parameters of the generator body model and the accessory model are initialized, including setting the initial states of the generator body model and the accessory model so that the parameters are consistent with the physical characteristics of the actual equipment; Using the voltage and current data at the generator end, combined with the stator reactance, the initial swing angle of the generator is used to represent the relative angle of the generator rotor relative to the grid, and the swing angle δ is calculated as follows: Where: i q and i d represents the current components on the q-axis and d-axis; All initialized parameters and calculated swing angles are input into the parameter data structure that simulates the transient dynamics of the generator and its accessories, and all key parameters related to the generator and its accessories model are organized and stored, including rotor angle, speed, mechanical power, voltage, current and excitation potential.

7. A simulation modeling method for transient calculation according to claim 6, characterized in that: The initial swing angle is as follows: In the initialization stage, the terminal voltage is Current and stator reactance x q , determine the virtual potential E Q The angle is used to represent the position of the q-axis in the dq coordinate system, and the virtual potential is calculated as follows: Where: U x , U y ,I x ,I y is the voltage and current decomposed into x and y axes.

8. The simulation modeling method for transient calculation according to claim 1, characterized in that: The generator body and accessory models are solved jointly to perform transient simulation calculations. By adjusting the order of the generator body model and selecting generator body models of different complexities, the simulation accuracy is dynamically adjusted as follows: Solve the generator body model and accessory model simultaneously, and process the dynamic response of the generator and its accessories in the transient process, so that the electrical and mechanical parts can operate synchronously; Transient simulation is performed through the combined generator body and accessory models. During the simulation process, the order of the generator body model is adjusted in real time to cope with transient response requirements of different complexities, taking into account the dynamic changes of simulated voltage, current and speed, so that the simulation results are consistent with the actual operating status.

9. A simulation modeling method for transient calculation according to claim 1 or 8, characterized in that: In transient simulation, the transfer functions of the generator body model and accessory model are converted into differential equations, and all differential equations are converted into differential equations through difference processing to meet the needs of discretization simulation; the simultaneous solution equations are calculated as follows: Δh g +Δh a =J k Δy g +Δy a Where: h g and h a Respectively represent the status of the generator body and accessory model; J k is the Jacobian matrix, as follows: The numerical iteration method is used to solve and calculate the dynamic response of the generator, including the changing parameters of the swing angle, voltage and speed; at each iteration, the Jacobian matrix is ​​updated and the numerical value of the next step is calculated until the set simulation accuracy is reached.

10. A generator body for transient calculation, comprising: Generator rotor model, stator winding, excitation model interface, transient reactance and capacitance elements, and data acquisition and control interface; characterized by: The generator rotor model is used to store and release mechanical energy in transient processes. The relative motion between the rotor and the stator generates electromotive force, and its characteristics reflect the dynamic response of the generator in the power grid. The stator winding generates three-phase alternating current through interaction with the rotor magnetic field, and the winding reactance effect in transient state is not taken into account to simplify the electrical characteristics in transient simulation calculation; The excitation model interface connects the generator body to the excitation model and controls the voltage output of the generator through the external excitation model; Transient reactance and capacitance elements are used to represent the electrical characteristics of the generator during transient processes. Used to adjust the dynamics of current and voltage to reflect the electromagnetic behavior of the generator in transient response; The data acquisition and control interface is used to monitor the operating status of the generator in real time, including key parameters such as voltage, current and speed. Through the control interface, the generator is linked with external control for dynamic adjustment.

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