Electromagnetic transient simulation method and system containing synchronous generator

Abstract

The invention provides an electromagnetic transient simulation method and system containing a synchronous generator, and is applied to the technical field of electromagnetic transient simulation of a power system. The electromagnetic transient simulation method comprising the synchronous generator comprises the following steps: acquiring a simulation equation of a circuit system to be simulated comprising the synchronous generator and a value of an electromagnetic transient state quantity of the circuit system at an initial moment; based on the value of the electromagnetic transient state quantity at the initial moment, adopting a Runge-Kutta algorithm to simulate the simulation equation to obtain a simulation value of the electromagnetic transient state quantity of the circuit system at the target moment; wherein the simulation equation is a port Hamiltonian form equation constructed based on the structure of the circuit system to be simulated. The port Hamiltonian-form simulation equation can keep numerical stability for a long time, calculation errors are reduced, an accurate and stable numerical solution can be obtained, and the requirements for long-time operation accuracy and stability in electromagnetic transient simulation numerical calculation are met.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic transient simulation of power systems, and particularly relates to an electromagnetic transient simulation method and system including a synchronous generator. Background Art

[0002] A typical electromagnetic transient simulation model divides the entire system into three modules: a circuit, a generator, and a mechanical shaft system. Each module is independently modeled and operated, and the information interaction between the modules will cause a time step delay, resulting in a decrease in numerical accuracy and stability.

[0003] To solve the above technical problems, a unified equation writing form and modeling method for a power system including a synchronous generator have been proposed in the related art. Compared with the classical electromagnetic transient simulation model, although this modeling method can avoid the delay caused by the information interaction between modules, the electromagnetic transient simulation solution obtained by solving the equation using a conventional method still cannot meet the requirements of the reproduction analysis of phenomena such as power system oscillations and the accuracy and stability requirements of long-time simulations; therefore, how to obtain an electromagnetic transient simulation solution with higher accuracy and higher stability for application in an electromagnetic transient simulation system, so that it can further meet the requirements of the reproduction analysis of phenomena such as power system oscillations and the numerical accuracy and stability requirements of long-time simulations, remains a problem to be solved in this field. Summary of the Invention

[0004] To overcome the above defects that do not meet the requirements of numerical accuracy and stability for long-time simulations, the present invention provides an electromagnetic transient simulation method including a synchronous generator, and the method includes:

[0005] Obtain the simulation equation of the circuit system including a synchronous generator to be simulated and the values of the electromagnetic transient state variables of the circuit system at the initial moment;

[0006] Based on the values of the electromagnetic transient state variables at the initial moment, use the Runge-Kutta algorithm to simulate the simulation equation to obtain the simulation values of the electromagnetic transient state variables of the circuit system at the target moment;

[0007] Wherein, the simulation equation is a port Hamiltonian form equation constructed based on the structure of the circuit system to be simulated.

[0008] Optionally, the construction process of the simulation equation includes:

[0009] Based on the structure of the circuit system including a synchronous generator to be simulated, construct a system differential equation with the node magnetic flux linkage of the circuit system and the mechanical shaft system of the synchronous generator as generalized coordinates;

[0010] Convert the differential equation of the system into the port-Hamiltonian form equation to obtain the simulation equation.

[0011] Optionally, based on the values of the electromagnetic transient state variables at the initial time, use the Runge-Kutta algorithm to simulate the simulation equation to obtain the simulation values of the electromagnetic transient state variables of the circuit system at the target time, including:

[0012] Divide S time points on the interval between the initial time and the target time;

[0013] Calculate the weighted average slope and weight coefficient corresponding to each time point;

[0014] Based on the weighted average slope, weight coefficient corresponding to each time point, and the values of the electromagnetic transient state variables at the initial time, use the S-step Runge-Kutta algorithm to calculate the simulation values of the electromagnetic transient state variables at the target time.

[0015] Optionally, the electromagnetic transient state variables include: the voltage of the circuit system, the node magnetic flux linkage of the circuit system, the mechanical angular velocity of the synchronous generator, and the mechanical angular displacement of the synchronous generator.

[0016] Optionally, the expression of the S-step Runge-Kutta algorithm is as follows:

[0017]

[0018] where, x h is the simulation value of the electromagnetic transient state variable x at the target time, x0 is the value of the electromagnetic transient state variable x at the initial time, h is the time step, b j is the weight coefficient, k j is the weighted average slope, s is the number of steps corresponding to the number of time points, j = 1, 2,..., s; the x0 and h satisfy the following formula:

[0019]

[0020] where, M, P, Q, z, N, V are coefficient matrices, k i is the slope at each point, a ij is the weight coefficient, and u is the input vector.

[0021] Optionally, the expression of the coefficient matrix M is as follows:

[0022] where, diag is the diagonal matrix, is the coefficient matrix of the inductive branch of the circuit system, J is the inertia matrix of the mechanical shafting, and K is the stiffness matrix of the mechanical shafting;

[0023] The expression of the coefficient matrix N is as follows:

[0024] N = diag(I4, 0, I6, 0, 1), where I4 and I6 are node injection current source vectors;

[0025] The expression of the coefficient matrix V is as follows:

[0026] V = S = W = 0, where S and W are coefficient matrices;

[0027] The expression of the coefficient matrix P is as follows:

[0028] Where, is the coefficient matrix of the inductive branch of the circuit system, and K is the stiffness matrix of the mechanical shaft system;

[0029] The expression of the coefficient matrix z is as follows:

[0030] Where, is the magnetic flux value of the circuit system, is the coefficient matrix of the inductive branch of the circuit system, is the inverse matrix of the inductance coefficient for calculating the magnetic field energy stored in the synchronous generator, is the magnetic flux vector, is the first derivative of the mechanical angular displacement, K is the stiffness matrix of the mechanical shaft system, θ is the mechanical angular displacement, is the magnetic flux vector, is the electromagnetic torque of the synchronous generator;

[0031] The expression of the coefficient matrix Q is as follows:

[0032] Where, is the coefficient matrix of the resistive branch of the circuit system, and D is the coefficient matrix of the friction loss of the mechanical shaft system.

[0033] Optionally, the weight coefficient a ij has the following expression:

[0034]

[0035] The weight coefficient b j has the following expression:

[0036] Where, l j (τ) satisfies γ j 、γ l 、γ i are real numbers, s is the number of steps corresponding to the number of time points, and l = 1, 2, …, s;

[0037] The weighted average slope kj The expression is as follows:

[0038] Wherein, is the electromagnetic transient state quantity parameter, t0 is the initial moment, and γ j is a real number, and h is the time step. Optionally, after obtaining the simulation value of the electromagnetic transient state quantity of the circuit system at the target moment by simulating the simulation equation using the Runge-Kutta algorithm based on the value of the electromagnetic transient state quantity at the initial moment, it further includes:

[0039] Calculating whether the error between the simulation value and the theoretical value of the electromagnetic transient state quantity meets the set error range.

[0040] Optionally, the expression for the error between the simulation value and the theoretical value of the electromagnetic transient state quantity meeting the set error range is as follows:

[0041]

[0042]

[0043]

[0044]

[0045] Wherein, is the theoretical value of the magnetic flux linkage of the circuit system at time t n , is the simulation value of the magnetic flux linkage of the circuit system at time t n ; is the theoretical value of the mechanical angular velocity of the synchronous generator of the circuit system at time t n , is the simulation value of the mechanical angular velocity of the synchronous generator of the circuit system at time t n ; θ n is the theoretical value of the mechanical angular displacement of the synchronous generator of the circuit system at time t n , θ(t n ) is the simulation value of the mechanical angular displacement of the synchronous generator of the circuit system at time t n ; is the theoretical value of the voltage of the circuit system at time t n , is the simulation value of the voltage of the circuit system at time t n ; t n = nh ≤ T m , h is the time step, T m is a constant independent of h; is the error precision, is the set error range, and s is the number of steps corresponding to the number of time points.

[0046] On the other hand, the present invention also provides an electromagnetic transient simulation system including a synchronous generator, comprising:

[0047] An acquisition module, configured to acquire the simulation equation of the circuit system including the synchronous generator to be simulated and the values of the electromagnetic transient state variables of the circuit system at the initial moment; wherein, the simulation equation is a port Hamiltonian form equation constructed based on the structure of the circuit system to be simulated.

[0048] A simulation module, configured to simulate the simulation equation by using the Runge-Kutta algorithm based on the values of the electromagnetic transient state variables at the initial moment, and obtain the simulation values of the electromagnetic transient state variables of the circuit system at the target moment.

[0049] Optionally, the acquisition module is further configured to construct a system differential equation with the node magnetic flux linkage of the circuit system and the mechanical shaft system of the synchronous generator as the generalized coordinates based on the structure of the circuit system including the synchronous generator to be simulated; convert the system differential equation into the port Hamiltonian form equation to obtain the simulation equation.

[0050] Optionally, the simulation module is specifically configured to divide S time points in the interval between the initial moment and the target moment; calculate the weighted average slope and weight coefficient corresponding to each time point; and calculate the simulation values of the electromagnetic transient state variables at the target moment by using the S-step Runge-Kutta algorithm based on the weighted average slope, weight coefficient corresponding to each time point, and the values of the electromagnetic transient state variables at the initial moment.

[0051] Optionally, the electromagnetic transient state variables include: the voltage of the circuit system, the node magnetic flux linkage of the circuit system, the mechanical angular velocity of the synchronous generator, and the mechanical angular displacement of the synchronous generator.

[0052] Optionally, the expression of the S-step Runge-Kutta algorithm is as follows:

[0053]

[0054] where, x h is the simulation value of the electromagnetic transient state variable x at the target moment, x0 is the value of the electromagnetic transient state variable x at the initial moment, h is the time step, b j is the weight coefficient, k j is the weighted average slope, s is the number of steps corresponding to the number of time points, j = 1, 2,..., s; the x0 and h satisfy the following formula:

[0055]

[0056] Among them, M, P, Q, z, N, and V are coefficient matrices, and k i is the slope of each point, and a ij is the weight coefficient, and u is the input vector.

[0057] Optionally, the expression of the coefficient matrix M is as follows:

[0058] Among them, diag is a diagonal matrix, is the coefficient matrix of the inductor branch of the circuit system, J is the inertia matrix of the mechanical shaft system, and K is the stiffness matrix of the mechanical shaft system;

[0059] The expression of the coefficient matrix N is as follows:

[0060] N = diag(I4, 0, I6, 0, 1), where I4 and I6 are the node injection current source vectors;

[0061] The expression of the coefficient matrix V is as follows:

[0062] V = S = W = 0, where S and W are coefficient matrices;

[0063] The expression of the coefficient matrix P is as follows:

[0064] Among them, is the coefficient matrix of the inductor branch of the circuit system, and K is the stiffness matrix of the mechanical shaft system;

[0065] The expression of the coefficient matrix z is as follows:

[0066] Among them, is the magnetic flux value of the circuit system, is the coefficient matrix of the inductor branch of the circuit system, is the inverse matrix of the inductance coefficient used to calculate the magnetic field energy stored in the synchronous generator, is the magnetic flux vector, is the first derivative of the mechanical angular displacement, K is the stiffness matrix of the mechanical shaft system, θ is the mechanical angular displacement, is the magnetic flux vector, is the electromagnetic torque of the synchronous generator;

[0067] The expression of the coefficient matrix Q is as follows:

[0068] Among them, is the coefficient matrix of the resistance branch of the circuit system, and D is the coefficient matrix of the friction loss of the mechanical shaft system.

[0069] Optionally, the weight coefficient a ij has the following expression:

[0070]

[0071] The weight coefficient b j has the following expression:

[0072] where l j (τ) satisfies γ j , γ l , γ i are real numbers, s is the number of steps corresponding to the number of time points, and l = 1, 2, …, s;

[0073] The weighted average slope k j has the following expression:

[0074] where is the electromagnetic transient state quantity parameter, t0 is the initial time, and γ j is a real number, and h is the time step.

[0075] Optionally, it further includes:

[0076] An error calculation module for calculating whether the error between the simulation value and the theoretical value of the electromagnetic transient state quantity meets the set error range.

[0077] Optionally, the expression for the error between the simulation value and the theoretical value of the electromagnetic transient state quantity meeting the set error range is as follows:

[0078]

[0079]

[0080]

[0081]

[0082] where is the theoretical value of the magnetic flux linkage of the circuit system at time t n , is the simulation value of the magnetic flux linkage of the circuit system at time t n ; is the theoretical value of the mechanical angular velocity of the synchronous generator of the circuit system at time t n , is the simulation value of the mechanical angular velocity of the synchronous generator of the circuit system at time t n ; θ n is the theoretical value of the mechanical angular displacement of the synchronous generator of the circuit system at time t n , θ(t n) is t n The simulated value of the mechanical angular displacement of the synchronous generator in the moment circuit system; is t n The theoretical value of the voltage of the moment circuit system, is t n The simulated value of the voltage of the moment circuit system; t n = nh ≤ T m , h is the time step, T m is a constant independent of h; is the set error range, and s is the number of steps corresponding to the number of the time points.

[0083] On the other hand, the present invention also provides a computer device, which is characterized by including: one or more processors;

[0084] The processor is used for storing one or more programs;

[0085] When the one or more programs are executed by the one or more processors, the electromagnetic transient simulation method including a synchronous generator described in any one of the above is implemented.

[0086] On the other hand, the present invention also provides a computer-readable storage medium, which is characterized in that a computer program is stored thereon, and when the computer program is executed, the electromagnetic transient simulation method including a synchronous generator described in any one of the above is implemented.

[0087] Compared with the closest prior art, the beneficial effects of the present invention are as follows:

[0088] The present invention provides an electromagnetic transient simulation method including a synchronous generator, which includes: obtaining a simulation equation of a circuit system including a synchronous generator to be simulated and the value of an electromagnetic transient state quantity of the circuit system at an initial moment; based on the value of the electromagnetic transient state quantity at the initial moment, using the Runge-Kutta algorithm to simulate the simulation equation to obtain a simulated value of the electromagnetic transient state quantity of the circuit system at a target moment; wherein, the simulation equation is a port Hamiltonian form equation constructed based on the structure of the circuit system to be simulated. The present invention uses a port Hamiltonian form simulation equation constructed based on the structure of the circuit system to participate in the electromagnetic transient simulation. The port Hamiltonian form simulation equation can maintain numerical stability for a long time and reduce calculation errors. Therefore, accurate and stable numerical solutions can be obtained, meeting the requirements of long-term operation accuracy and stability in the numerical calculation of electromagnetic transient simulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0089] Figure 1 It is a schematic flow chart of the electromagnetic transient simulation method including a synchronous generator of the present invention;

[0090] Figure 2Schematic diagram of the stable single-machine infinite system of the present invention;

[0091] Figure 3 Schematic diagram for comparing the numerical simulation results of the generator rotor within 0 - 15 s of the present invention;

[0092] Figure 4 Comparison of the numerical simulation results of the generator rotor within 0 - 1000 s of the present invention;

[0093] Figure 5 Schematic diagram of the structure of the electromagnetic transient simulation system containing a synchronous generator of the present invention. Specific embodiments

[0094] The following further elaborates on the specific embodiments of the present invention with reference to the accompanying drawings.

[0095] Example 1:

[0096] Regarding the problems existing in classical electromagnetic transient simulation programs, there are currently literatures that use Euler - Lagrange equations with node magnetic flux and mechanical angular displacement as generalized coordinates to propose a unified equation writing form and modeling method for power systems containing synchronous generators. When solving this equation, conventional numerical solutions of differential equations are used, but there are problems with numerical accuracy and stability, and it cannot meet the requirements of accuracy and stability for the reproduction analysis of power system oscillations and long - time simulations. Therefore, it is necessary to explore numerical solution methods with higher accuracy and greater stability that can be applied in electromagnetic transient simulation systems.

[0097] Based on this, the present invention provides an electromagnetic transient simulation method for a power system containing a synchronous generator. The flow schematic diagram is as Figure 1 shown, including:

[0098] Step 101: Obtain the simulation equation of the circuit system containing a synchronous generator to be simulated and the values of the electromagnetic transient state variables of the circuit system at the initial moment. Among them, the simulation equation is a port - Hamiltonian - form equation constructed based on the structure of the circuit system to be simulated.

[0099] Step 102: Based on the values of the electromagnetic transient state variables at the initial moment, use the Runge - Kutta algorithm to simulate the simulation equation to obtain the simulation values of the electromagnetic transient state variables of the circuit system at the target moment.

[0100] The embodiment of the present invention uses a port - Hamiltonian - form simulation equation constructed based on the structure of the circuit system to participate in electromagnetic transient simulation. The port - Hamiltonian - form simulation equation can maintain numerical stability for a long time and reduce calculation errors. Therefore, accurate and stable numerical solutions can be obtained, meeting the requirements of accuracy and stability for long - time operation in electromagnetic transient simulation numerical calculations.

[0101] In one implementation, the construction process of the simulation equation in step 101 above includes: based on the structure of the circuit system including a synchronous generator to be simulated, constructing a system differential equation with the node magnetic flux linkage of the circuit system and the mechanical shaft system of the synchronous generator as generalized coordinates; converting the system differential equation into a port Hamiltonian form equation to obtain the simulation equation.

[0102] Exemplarily, the system differential equation with the node magnetic flux linkage of the circuit system and the mechanical shaft system of the synchronous generator as generalized coordinates, that is, the system calculus equation including the synchronous generator and its mechanical shaft system can satisfy the following formula (1):

[0103]

[0104] where J is the inertia matrix of the mechanical shaft system, K is the stiffness matrix of the mechanical shaft system; K C is the coefficient matrix of the capacitor branch in the circuit system, K L is the coefficient matrix of the inductor branch in the circuit system; Γ(θ) is the inverse matrix of the inductance coefficient used to calculate the magnetic field energy stored in the generator; K R is the coefficient matrix of the resistance branch in the circuit system, D is the coefficient matrix of the friction loss of the mechanical shaft system; is the electromagnetic torque of the generator; T represents the mechanical torque vector, I s (t) represents the node injection current source vector, Ψ is the node magnetic flux linkage in abc coordinates, and the abc coordinates are in the form of the normal abc three-phase; is the first derivative of the node magnetic flux linkage, is the second derivative of the node magnetic flux linkage, θ is the mechanical angular displacement, is the first derivative of the mechanical angular displacement, is the second derivative of the mechanical angular displacement.

[0105] By rewriting the above system calculus equation including the synchronous generator, the singularity of K R can be eliminated. Observation shows that the derivatives of Ψ 2α , Ψ 2β do not appear in the generator system equation. Therefore, we can naturally replace Ψ 2α , Ψ 2β with the remaining variables to obtain the following formula (1-1):

[0106] Ψ 2α =λ1Ψ 1α +λ2(-Ψ f cosθ5+Ψ q sinθ5),

[0107] Ψ 2β =λ1Ψ 1β +λ2(-Ψf sinθ5 - Ψ q cosθ5), (1 - 1)

[0108] If there are 2 three - phase nodes in the system, Ψ 2α , Ψ 2β is the node flux linkage of node 2 in the αβ coordinate system, Ψ 1α , Ψ 1β are the stator winding α - axis flux linkage and the stator winding β - axis flux linkage respectively, Ψ f is the field winding flux linkage, Ψ q is the rotor q - axis winding flux linkage, θ5 is the mechanical angular displacement parameter, where the coefficients λ1 and λ2 satisfy the following formula (1 - 2):

[0109]

[0110] where, L r is the self - inductance of the rotor winding, L s is the self - inductance of the stator winding, M s is the mutual inductance of the stator windings, M is the mutual inductance between the stator and rotor windings, and L is the leakage inductance.

[0111] Substituting the above formula (1 - 1) into the system calculus equation (1) of the system containing a synchronous generator, a new flux linkage vector can be obtained as shown in the following formula (1 - 3):

[0112]

[0113] where, Ψ 1α is the stator winding α - axis flux linkage, Ψ 1β is the stator winding β - axis flux linkage, Ψ f is the field winding flux linkage, Ψ q is the rotor q - axis winding flux linkage.

[0114] Another example is that the process of converting the system differential equation into the port - Hamiltonian form equation includes: The autonomous generalized port - Hamiltonian system equation rewritten from the above - mentioned system calculus equation (1) of the system containing a synchronous generator can satisfy the following formula (2):

[0115]

[0116] where, is the voltage value of the circuit system, is the flux linkage value of the circuit system, is the resistance matrix of the circuit system, is the inductance matrix of the circuit system, is the inverse matrix of the inductance coefficient for calculating the magnetic field energy stored in the synchronous generator in the αβ coordinate system, Denote the node injection current source vector parameter, J is the inertia matrix of the mechanical shafting, K is the stiffness matrix of the mechanical shafting, D is the coefficient matrix of the friction loss of the mechanical shafting, θ is the mechanical angular displacement, is the first derivative of the mechanical angular displacement, is the second derivative of the mechanical angular displacement, is the electromagnetic torque of the generator; T represents the mechanical torque vector.

[0117] Let the state quantity x(t), input vector u(x), and output vector y(x) in the above formula (2) satisfy the following formula (2-1):

[0118]

[0119] where, is the voltage value of the circuit system, is the magnetic flux linkage value of the circuit system, θ is the mechanical angular displacement, is the first derivative of the mechanical angular displacement, t represents the time t, T represents the mechanical torque vector, denotes the node injection current source vector parameter.

[0120] The above formula (2) can be rewritten as a port Hamiltonian form equation, that is, the above simulation equation, for example, satisfying the following formula (3):

[0121]

[0122]

[0123] where, u(x) is the input quantity of the system, for example, including ideal source current and / or mechanical torque, etc., M, P, Q, z(x), N, V, S, W are coefficient matrices, is the input quantity parameter, y is the output quantity parameter.

[0124] Considering that is the generalized displacement of the system, is the generalized velocity, so formula (3) has a Hamiltonian function. The coefficient matrices M, N, P, and Q therein satisfy the following formula (3-1):

[0125]

[0126]

[0127] where, diag is a diagonal matrix, is the coefficient matrix of the inductor branch of the circuit system, J is the inertia matrix of the mechanical shafting, K is the stiffness matrix of the mechanical shafting; I4, I6 are the node injection current source vectors; V, S, W are coefficient matrices; is the coefficient matrix of the inductance branch of the circuit system, and K is the stiffness matrix of the mechanical shafting; is the coefficient matrix of the resistance branch of the circuit system, and D is the coefficient matrix of the frictional loss of the mechanical shafting.

[0128] And there is z(x) satisfying the following formula (3-2):

[0129]

[0130] where, z(x) and z have the same physical meaning and are coefficient matrices, is the magnetic flux linkage value of the circuit system, is the coefficient matrix of the inductance branch of the circuit system, is the inverse matrix of the inductance coefficient used to calculate the magnetic field energy stored in the synchronous generator, is the magnetic flux linkage vector, is the first derivative of the mechanical angular displacement, K is the stiffness matrix of the mechanical shafting, and θ is the mechanical angular displacement, is the magnetic flux linkage vector, is the electromagnetic torque of the synchronous generator.

[0131] The structure-preserving algorithm is a numerical method constructed in the dynamic system by maintaining the inherent structure and characteristics of the system, which can maintain the long-term stability of numerical calculation. Therefore, in the embodiments of the present invention, a structure-preserving algorithm for a synchronous generator system based on the port Hamiltonian form is proposed. This algorithm can maintain numerical stability for a long time and has a small calculation error.

[0132] Exemplarily, the electromagnetic transient state variables include one or more of the following: the voltage of the circuit system, the node magnetic flux linkage of the circuit system, the mechanical angular velocity of the synchronous generator, and the mechanical angular displacement of the synchronous generator. That is, the voltage of the circuit system, the node magnetic flux linkage, the mechanical angular velocity of the synchronous generator, and the mechanical angular displacement can represent the electromagnetic transient state variables, which means that the simulation values of the electromagnetic transient state variables can be determined according to the simulation values of these variables.

[0133] In a possible implementation manner, in step 102 above, S time points can be divided in the interval between the initial time and the target time; calculate the weighted average slope and weight coefficient corresponding to each time point; based on the weighted average slope, weight coefficient corresponding to each time point, and the value of the electromagnetic transient state variable at the initial time, use the S-step Runge-Kutta algorithm to calculate the simulation value of the electromagnetic transient state variable at the target time. Where represents a positive integer.

[0134] Exemplarily, the S-step Runge-Kutta algorithm satisfies the following formula (4):

[0135]

[0136] where x h is the simulation value of the electromagnetic transient state quantity x at the target time, which is the simulation value to be solved, and is equivalent to obtaining x based on x0 and the above coefficient matrix h , x h is the solution of x at the time t = t0 + h. x0 is the value of the electromagnetic transient state quantity x at the initial time, which is the initial value of x at t = t0, h is the time step, and b j is the weight coefficient, k j is the weighted average slope, s is the number of steps corresponding to the number of time points, and j = 1, 2,..., s.

[0137] x0 and h satisfy the following formula:

[0138]

[0139] where M, P, Q, z, N, V are coefficient matrices, and k i is the slope at each point, k j is the weighted average slope, a ij is the weight coefficient, and u is the input vector. Each coefficient matrix in the formula satisfies the above formula (3-1), formula (3-2), and the weight coefficient in the formula where γ j , γ l are real numbers, s is the number of steps corresponding to the number of time points, and l = 1, 2,..., s; the weighted average slope in the formula where is the electromagnetic transient state quantity parameter, t0 is the initial time, γ i is a real number, h is the time step, and τ is the time variable.

[0140] The above formula (4) can be regarded as the expression for solving each step. When obtaining the simulation at the target time by substituting the corresponding system parameters and simulation time during the solution, using the S-step Runge-Kutta algorithm to calculate the simulation value of the electromagnetic transient state quantity can be regarded as using the above solution equation to obtain a discrete expression, and as time goes by, it is solved iteratively forward.

[0141] The following introduces the relevant steps of the S-step Runge-Kutta algorithm:

[0142] First, introduce the configuration polynomial. Consider the non-autonomous first-order ordinary differential equation, as shown in the following formula (5):

[0143]

[0144] Here f is a differentiable function with sufficient smoothness, t represents the time at t, and t0 is the initial time, is the derivative of the state variable, v is the state variable, and v0 is the initial value of the state variable. Let γ1, …, γ s be distinct real numbers in the interval [0, 1]. Then the s-th degree polynomial that satisfies the following conditions is the collocation polynomial of formula (5), and the numerical solution of the corresponding collocation method is given by . In fact, the collocation method can be equivalently transformed into an s-step Runge-Kutta algorithm. Among them, is the value of the state variable collocation polynomial, v0 is the initial value of the state variable, γ i is a real number, t0 is the initial time, h is the time step, and s is the polynomial degree.

[0145] The following introduces its specific steps:

[0146] Take the slope is the collocation polynomial of formula (3) with degree s. Therefore, is a polynomial of degree s - 1. According to the Lagrange interpolation formula, there is the following formula (6):

[0147]

[0148] Among them, is the Lagrange interpolation polynomial, is a polynomial of degree s - 1, t0 is the initial time, h is the time step, τ is a coefficient within one time step (0 ≤ τ ≤ 1), k j is the weighted average slope, γ j and γ l are distinct real numbers, s is the polynomial degree, j = 1, 2, …, s, and l = 1, 2, …, s.

[0149] Integrating formula (6) gives the following formula (7):

[0150]

[0151]

[0152] Among them, is the form of writing the sum of formula (6) as an integral, t0 is the initial time, h is the time step, γ i is a real number, v0 is the initial value of the state variable, k j is the weighted average slope, l j (τ) is the Lagrange interpolation polynomial, s is the polynomial degree, and j = 1, 2, …, s.

[0153] Thus, an s-step Runge-Kutta algorithm can be obtained:

[0154]

[0155]

[0156] where \(t_0\) is the initial time, \(\Delta t\) is the time step, \(x_0\) is the initial value of \(x\) at \(t = t_0\), and \(x\) h is the approximate solution of \(x\) at \(t = t_0+\Delta t\), \(M\), \(P\), \(Q\), \(z\), \(N\), \(V\) are coefficient matrices, and \(k\) i is the slope at each point, and \(a\) ij is the weight coefficient, \(u\) is the input vector, and \(k\) j is the weighted average slope, \(s\) represents the number of steps, \(j = 1,2,\cdots,s\), and \(b\) j is the weight coefficient.

[0157] where the \(a\) ij , \(b\) i The coefficient is specifically expressed as:

[0158]

[0159] where \(a\) ij is the weight coefficient, \(\gamma\) i is a real number, \(l\) j \((\tau)\) is the Lagrange interpolation polynomial, and \(b\) i is the weight coefficient.

[0160] In particular, when \(\gamma_1,\cdots,\gamma\) s is the \(s\) - th shifted Legendre polynomial:

[0161]

[0162] are the zeros of, the methods given by equations (4) and (8) are the \(s\) - step Gauss method, that is, the \(s\) - step Runge - Kutta algorithm. The \(s\) - step Gauss method obtained by the above method has the structure - preserving property and can maintain the long - term stability of numerical calculations. Here, \(s\) represents the number of steps, and \(x\) represents the unknown state variable.

[0163] In one implementation, after the above step 102, it is also possible to calculate whether the error between the simulation value and the theoretical value of the electromagnetic transient state quantity satisfies a set error range. For example, calculate whether the error between the magnetic - flux simulation value of the circuit system and the magnetic - flux theoretical value of the circuit system satisfies the magnetic - flux error range, or calculate whether the error between the mechanical angular - velocity simulation value of the synchronous generator and the mechanical angular - velocity theoretical value of the synchronous generator satisfies the mechanical angular - velocity error range, or calculate whether the error between the mechanical angular - displacement simulation value of the synchronous generator and the mechanical angular - displacement theoretical value of the synchronous generator satisfies the mechanical angular - displacement error range, or calculate whether the error between the voltage simulation value of the circuit system and the voltage theoretical value of the circuit system satisfies the voltage error range.

[0164] The s-step Gaussian method is applied to the generator system (3) in the port Hamiltonian form, and the corresponding specific form is formula (4). Assuming that the initial value of the generator system (3) is consistent, the global error of the numerical solution given by formula (4) satisfies the following formula, that is, the error between the simulation value and the theoretical value of the electromagnetic transient state quantity satisfies the set error range expression as follows:

[0165]

[0166]

[0167]

[0168]

[0169] in, t n The theoretical value of the magnetic flux of the circuit system at the moment, t n The magnetic flux simulation value of the circuit system at the moment; t n The theoretical value of the mechanical angular velocity of the synchronous generator of the circuit system at the moment, t n The mechanical angular velocity simulation value of the synchronous generator of the circuit system at the moment; θ n t n The theoretical value of the mechanical angular displacement of the synchronous generator of the circuit system at the moment, θ(t n ) is t n Mechanical angular displacement simulation value of the synchronous generator of the instantaneous circuit system; t n The theoretical voltage value of the circuit system at this moment, t n The voltage simulation value of the circuit system at time t n =nh≤T m ,h is the time step, T m is a constant that is independent of h; is the error accuracy, is the set error range / error accuracy, and s is the number of steps corresponding to the number of time points.

[0170] If the error of the simulation value is within the corresponding error range, it means that the error of the simulation value is small and the accuracy of the simulation value can be guaranteed. This method is used to numerically simulate a system containing a synchronous generator, and then the simulation result, i.e., the theoretical value, is compared with the numerical calculation results. The structure-preserving algorithm has outstanding advantages in terms of accuracy and long-term calculation stability.

[0171] The embodiments of the present invention will be described below with a specific example.

[0172] The embodiments of the present invention perform numerical simulation on Figure 2 the circuit system including a synchronous generator shown, using a simulation step size of h = 10 -4 s. Among them Figure 2 (a) in represents a schematic diagram of the circuit part of the circuit system, Figure 2 (b) in represents a schematic diagram of the generator of the circuit system, Figure 2 (c) in represents a schematic diagram of the mechanical shafting part of the circuit system.

[0173] Figure 3 is a schematic diagram of the comparison of the numerical simulation results of the generator rotor within 0 - 15 s, Figure 4 is a schematic diagram of the comparison of the numerical simulation results of the generator rotor within 0 - 1000 s. According to Figure 3 and Figure 4 the comparison schematic diagram of the simulation values of the method of this patent and the simulation results (i.e., theoretical values) of the PSCAD / EMTDC software (an electromagnetic transient simulation software) shown, it can be seen that the method provided by the embodiments of the present invention can maintain the accuracy of the numerical value stably for a long time, reflecting the superiority of the method of the present invention.

[0174] In the embodiments of the present invention, the generator system is re - expressed from the perspective of a structure - preserving dynamic system, and its structure - preserving algorithm is constructed. Since the energy dissipation in the generator system is caused by resistance loss and friction loss, it is not appropriate to use the symplectic structure of the Hamiltonian system to describe this system. Therefore, we need to turn to a more general framework, that is, introducing the generalized port - Hamiltonian system. In fact, the generalized port - Hamiltonian system can describe the energy dissipation phenomenon and is related to the Dirac structure. On this basis, we will prove that the generator system can be re - expressed as a generalized port - Hamiltonian system, and then a structure - preserving algorithm can be constructed for it.

[0175] To illustrate the structure - preserving property of the algorithm, the formula (1) of the synchronous generator system is rewritten as an autonomous generalized port - Hamiltonian system. For example, the coefficient matrix K C = 0 6×6 , and K R is also a singular matrix. Therefore, the voltage vector of the system cannot be directly expressed by the remaining variables through the first equation in formula (1), which prompts us to consider eliminating the singularity of the matrix K R by rewriting the generator system (1). Observation shows that the derivatives of Ψ 2α , Ψ 2β do not appear in the generator system equation. Therefore, we can naturally replace Ψ 2α , Ψ 2β with the remaining variables, that is, the above formula (1 - 1).

[0176] If there are two three-phase nodes in the system, Ψ 2α , Ψ 2β is the node flux linkage of node 2 in the αβ coordinate system, where λ1 and λ2 satisfy the above formula (1-2). Substituting the above formula (1-1) into the system calculus equation (1) of the synchronous generator system above, a new flux linkage vector can be obtained as shown in the above formula (1-3). Therefore, a new generator system equation (generalized port Hamiltonian equation) can be obtained, as shown in the above formula (2).

[0177] Among them, is the flux linkage vector, is the inverse matrix of the inductance coefficient used to calculate the magnetic field energy stored in the synchronous generator, θ is the mechanical angular displacement, and θ5 is the mechanical angular displacement parameter;

[0178] And

[0179]

[0180]

[0181]

[0182] is the coefficient matrix of the resistance branch of the circuit system, diag is the diagonal matrix, R is the resistance, is the resistance parameter of the field winding, is the resistance parameter of the rotor q-axis winding, represents the node injection current source vector parameter, U s U f is the voltage parameter, R f is the resistance parameter, ω s is the angular velocity parameter, t represents the moment of t, is the inductance matrix of the circuit system, L r is the self-inductance of the rotor winding, L s is the self-inductance of the stator winding, M s is the mutual inductance of the stator windings, M is the mutual inductance between the stator and rotor windings, L is the leakage inductance, and Γ(θ) is the matrix parameter of the inductance coefficient used to calculate the magnetic field energy stored in the synchronous generator in the αβ coordinate system;

[0183] Let

[0184]

[0185] The simulation equation as shown in the above formula (3) can be obtained, where x(t) represents the state quantity, u(x) represents the input vector, and y(x) represents the output vector, is the voltage value of the circuit system, is the magnetic flux linkage value of the circuit system, θ is the mechanical angular displacement, is the first derivative of the mechanical angular displacement, t represents the moment of t, T represents the mechanical torque vector, represents the node injection current source vector parameter.

[0186] The coefficient matrix therein is shown in the above formulas (3-1) to (3-2). In addition, considering that is the generalized displacement of the new system formula (3), and is the generalized velocity, so the new system formula (3) has a Hamiltonian function:

[0187]

[0188] Among them, represents the Hamiltonian function, represents the first derivative of the mechanical angular displacement, J represents the inertia matrix of the mechanical shafting, represents the voltage value of the circuit system, represents the inductance matrix of the circuit system, represents the inverse matrix of the inductance coefficient used to calculate the magnetic field energy stored in the synchronous generator in the αβ coordinate system, θ represents the mechanical angular displacement, K represents the stiffness matrix of the mechanical shafting.

[0189] The matrices Ξ and Λ can be verified:

[0190] where P, N, W, Q, V, S are coefficient matrices;

[0191] satisfy

[0192] Among them and represent the transpose matrix,

[0193] And

[0194] Among them is the Hamiltonian operator parameter, is the Hamiltonian function, M and z are coefficient matrices.

[0195] Therefore, the new system formula (3) is actually a generalized port Hamiltonian system and is related to the Dirac structure.

[0196] Embodiment 2:

[0197] Based on the same inventive concept, the present invention also provides an electromagnetic transient simulation system including a synchronous generator, and the structural schematic diagram is as Figure 5 shown, including:

[0198] An acquisition module, configured to acquire the simulation equations of a circuit system including a synchronous generator to be simulated and the values of the electromagnetic transient state variables of the circuit system at an initial moment; wherein, the simulation equations are port Hamiltonian form equations constructed based on the structure of the circuit system to be simulated.

[0199] A simulation module, configured to simulate the simulation equations by using the Runge-Kutta algorithm based on the values of the electromagnetic transient state variables at the initial moment, and obtain the simulation values of the electromagnetic transient state variables of the circuit system at a target moment.

[0200] In a possible implementation manner, the acquisition module is further configured to construct a system differential equation with the node magnetic flux linkage of the circuit system and the mechanical shaft system of the synchronous generator as generalized coordinates based on the structure of the circuit system including the synchronous generator to be simulated; convert the system differential equation into the port Hamiltonian form equation to obtain the simulation equations.

[0201] In a possible implementation manner, the simulation module is specifically configured to divide S time points in the interval between the initial moment and the target moment; calculate the weighted average slopes and weight coefficients corresponding to each time point; calculate the simulation values of the electromagnetic transient state variables at the target moment by using the S-step Runge-Kutta algorithm based on the weighted average slopes, weight coefficients corresponding to each time point, and the values of the electromagnetic transient state variables at the initial moment.

[0202] In a possible implementation manner, the electromagnetic transient state variables include: the voltage of the circuit system, the node magnetic flux linkage of the circuit system, the mechanical angular velocity of the synchronous generator, and the mechanical angular displacement of the synchronous generator.

[0203] In a possible implementation manner, the expression of the S-step Runge-Kutta algorithm is as follows:

[0204]

[0205] Wherein, x h is the simulation value of the electromagnetic transient state variable x at the target moment, x0 is the value of the electromagnetic transient state variable x at the initial moment, h is the time step, b j is the weight coefficient, k j is the weighted average slope, s is the number of steps corresponding to the number of time points, j = 1, 2,..., s; the x0 and h satisfy the following formula:

[0206]

[0207] Wherein, M, P, Q, z, N, V are coefficient matrices, k i is the slope at each point, k j is the weighted average slope, a ijis the weight coefficient, and u is the input vector.

[0208] In a possible implementation, the expression of the coefficient matrix M is as follows:

[0209] where diag is a diagonal matrix, is the coefficient matrix of the inductor branch of the circuit system, J is the inertia matrix of the mechanical shafting, and K is the stiffness matrix of the mechanical shafting;

[0210] The expression of the coefficient matrix N is as follows:

[0211] N = diag(I4, 0, I6, 0, 1), where I4 and I6 are the node injection current source vectors;

[0212] The expression of the coefficient matrix V is as follows:

[0213] V = S = W = 0, where S and W are coefficient matrices;

[0214] The expression of the coefficient matrix P is as follows:

[0215] where, is the coefficient matrix of the inductor branch of the circuit system, and K is the stiffness matrix of the mechanical shafting;

[0216] The expression of the coefficient matrix z is as follows:

[0217] where, is the magnetic flux value of the circuit system, is the coefficient matrix of the inductor branch of the circuit system, is the inverse matrix of the inductance coefficient for calculating the magnetic field energy stored in the synchronous generator, is the magnetic flux vector, is the first derivative of the mechanical angular displacement, K is the stiffness matrix of the mechanical shafting, θ is the mechanical angular displacement, is the magnetic flux vector, is the electromagnetic torque of the synchronous generator;

[0218] The expression of the coefficient matrix Q is as follows:

[0219] where, is the coefficient matrix of the resistor branch of the circuit system, and D is the coefficient matrix of the friction loss of the mechanical shafting.

[0220] In a possible implementation, the weight coefficient a ij has the following expression:

[0221]

[0222] The weight coefficient b j has the following expression:

[0223] where l j (τ) satisfies γ j , γ l , γ i are real numbers, s is the number of steps corresponding to the number of time points, and l = 1, 2, …, s;

[0224] The weighted average slope k j has the following expression:

[0225] where is the electromagnetic transient state quantity parameter, t0 is the initial time, and γ j is a real number, and h is the time step.

[0226] In a possible implementation, it further includes:

[0227] An error calculation module, configured to calculate whether the error between the simulation value and the theoretical value of the electromagnetic transient state quantity meets a set error range.

[0228] In a possible implementation, the expression for the error between the simulation value and the theoretical value of the electromagnetic transient state quantity meeting the set error range is as follows:

[0229]

[0230]

[0231]

[0232]

[0233] where is the theoretical value of the magnetic flux linkage of the circuit system at time t n , is the simulation value of the magnetic flux linkage of the circuit system at time t n ; is the theoretical value of the mechanical angular velocity of the synchronous generator of the circuit system at time t n , is the simulation value of the mechanical angular velocity of the synchronous generator of the circuit system at time t n ; θ n is the theoretical value of the mechanical angular displacement of the synchronous generator of the circuit system at time t n , and θ(t n ) is at time t nThe simulated mechanical angular displacement of the synchronous generator in the moment circuit system; is t n The theoretical voltage value of the moment circuit system, is t n The simulated voltage value of the moment circuit system; t n = nh ≤ T m , where h is the time step, T m is a constant independent of h; is the set error range, and s is the number of steps corresponding to the number of time points.

[0234] Embodiment 3:

[0235] Based on the same inventive concept, the present invention also provides a computer device, which includes a processor and a memory. The memory is used to store a computer program, and the computer program includes program instructions. 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 may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, and is suitable for implementing one or more instructions. Specifically, it is suitable for loading and executing one or more instructions in the computer storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of an electromagnetic transient simulation method including a synchronous generator in the above embodiment.

[0236] Embodiment 4:

[0237] Based on the same inventive concept, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory). A computer-readable storage medium is a memory device in a computer device, used to store programs and data. It can be understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and, of course, the extended storage medium supported by the computer device. The computer-readable storage medium provides a storage space, and this storage space stores the operating system of the terminal. Moreover, in this storage space, there is also stored one or more instructions suitable for being loaded and executed by a processor. 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 one or more instructions stored in the computer-readable storage medium can be loaded and executed by the processor to implement the steps of the electromagnetic transient simulation method with a synchronous generator in the above embodiments.

[0238] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0239] The present invention is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram can be implemented by computer program instructions, and the combination of the flows and / or blocks in the flowchart and / or block diagram can also be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the specified functions in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0240] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device, and the instruction device implements the specified functions in Figure 1 one flow or multiple flows and / or blocks Figure 1The functions specified in one or more boxes.

[0241] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide for implementing the steps of the functions specified in one Figure 1 one process or more processes and / or boxes Figure 1 step of the functions specified in one box or more boxes.

[0242] 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 the scope of its protection. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that after reading the present invention, various changes, modifications or equivalent replacements can still be made to the specific implementation manners of the application. However, these changes, modifications or equivalent replacements are all within the scope of the protection of the claims pending for approval of the application.

Claims

1. An electromagnetic transient simulation method including a synchronous generator, characterized in that, The method includes: Obtaining the simulation equation of a circuit system including a synchronous generator to be simulated and the values of the electromagnetic transient state variables of the circuit system at the initial moment; Based on the values of the electromagnetic transient state variables at the initial moment, using the Runge-Kutta algorithm to simulate the simulation equation to obtain the simulation values of the electromagnetic transient state variables of the circuit system at the target moment; Wherein, the simulation equation is a port Hamiltonian form equation constructed based on the structure of the circuit system to be simulated.

2. The method according to claim 1, wherein The construction process of the simulation equation includes: Based on the structure of the circuit system including a synchronous generator to be simulated, constructing a system differential equation with the node magnetic flux linkage of the circuit system and the mechanical shaft system of the synchronous generator as generalized coordinates; Converting the system differential equation into the port Hamiltonian form equation to obtain the simulation equation.

3. The method according to claim 2, wherein The step of using the Runge-Kutta algorithm to simulate the simulation equation based on the values of the electromagnetic transient state variables at the initial moment to obtain the simulation values of the electromagnetic transient state variables of the circuit system at the target moment includes: Dividing S time points in the interval between the initial moment and the target moment; Calculating the weighted average slope and weight coefficient corresponding to each time point; Based on the weighted average slope, weight coefficient corresponding to each time point and the values of the electromagnetic transient state variables at the initial moment, using the S-step Runge-Kutta algorithm to calculate the simulation values of the electromagnetic transient state variables at the target moment.

4. The method according to claim 1, characterized in that, The electromagnetic transient state variables include: the voltage of the circuit system, the node magnetic flux linkage of the circuit system, the mechanical angular velocity of the synchronous generator, and the mechanical angular displacement of the synchronous generator.

5. The method according to claim 3, characterized in that The expression of the S-step Runge-Kutta algorithm is as follows: where x h is the simulation value of the electromagnetic transient state variable x at the target time, x0 is the value of the electromagnetic transient state variable x at the initial time, h is the time step, and b j is the weight coefficient, k j is the weighted average slope, s is the number of steps corresponding to the number of time points, j = 1, 2,..., s; the x0 and h satisfy the following formula: where M, P, Q, z, N, V are coefficient matrices, and k i is the slope of each point, a ij is the weight coefficient, and u is the input vector.

6. The method according to claim 5, characterized in that, The expression of the coefficient matrix M is as follows: where diag is a diagonal matrix, is the coefficient matrix of the inductive branch of the circuit system, J is the inertia matrix of the mechanical shaft system, and K is the stiffness matrix of the mechanical shaft system; The expression of the coefficient matrix N is as follows: N = diag(I4, 0, I6, 0, 1), where I4 and I6 are node injection current source vectors; The expression of the coefficient matrix V is as follows: V = S = W = 0, where S and W are coefficient matrices; The expression of the coefficient matrix P is as follows: Among them, is the coefficient matrix of the inductive branch of the circuit system, and K is the stiffness matrix of the mechanical shafting; The expression of the coefficient matrix z is as follows: Among them, is the magnetic flux linkage value of the circuit system, is the coefficient matrix of the inductance branch of the circuit system, is the inverse matrix of the inductance coefficient used to calculate the magnetic field energy stored in the synchronous generator, is the magnetic flux linkage vector, is the first derivative of the mechanical angular displacement, K is the stiffness matrix of the mechanical shaft system, θ is the mechanical angular displacement, is the magnetic flux linkage vector, is the electromagnetic torque of the synchronous generator, x is the electromagnetic transient state variable; The expression of the coefficient matrix Q is as follows: Among them, is the coefficient matrix of the resistance branch of the circuit system, and D is the coefficient matrix of the frictional loss of the mechanical shafting.

7. The method according to claim 5 or 6, characterized in that The weight coefficient a ij has the following expression: The weight coefficient b j has the following expression: Among them, l j (τ) satisfies γ j , γ l , γ i are real numbers, s is the number of steps corresponding to the number of time points, l = 1, 2, …, s; The weighted average slope k j has the following expression: Among them, is the electromagnetic transient state quantity parameter, t0 is the initial moment, and γ j is a real number, and h is the time step.

8. The method according to claim 1, characterized in that, After using the Runge-Kutta algorithm to simulate the simulation equation based on the values of the electromagnetic transient state variables at the initial moment to obtain the simulation values of the electromagnetic transient state variables of the circuit system at the target moment, it further includes: Calculating whether the error between the simulation values and the theoretical values of the electromagnetic transient state variables meets the set error range.

9. The method according to claim 8, wherein The expression for the error between the simulation values and the theoretical values of the electromagnetic transient state variables meeting the set error range is as follows: in, t n The theoretical value of the magnetic flux of the circuit system at the moment, t n The magnetic flux simulation value of the circuit system at the moment; t n The theoretical value of the mechanical angular velocity of the synchronous generator of the circuit system at the moment, t n The mechanical angular velocity simulation value of the synchronous generator of the circuit system at the moment; θ n t n The theoretical value of the mechanical angular displacement of the synchronous generator of the circuit system at the moment, θ(t n ) is t n Mechanical angular displacement simulation value of the synchronous generator of the instantaneous circuit system; t n The theoretical voltage value of the circuit system at this moment, t n The voltage simulation value of the circuit system at time t n =nh≤T m ,h is the time step, T m is a constant that is independent of h; is the set error range, and s is the number of steps corresponding to the number of time points.

10. An electromagnetic transient simulation system including a synchronous generator, the system includes: An acquisition module for obtaining the simulation equation of a circuit system including a synchronous generator to be simulated and the values of the electromagnetic transient state variables of the circuit system at the initial moment; wherein, the simulation equation is a port Hamiltonian form equation constructed based on the structure of the circuit system to be simulated; A simulation module, configured to perform simulation on the simulation equation by using the Runge-Kutta algorithm based on the values of the electromagnetic transient state variables at the initial moment, so as to obtain the simulation values of the electromagnetic transient state variables of the circuit system at the target moment.

11. The system according to claim 10, wherein The obtaining module is further configured to construct a system differential equation with the node magnetic flux linkage of the circuit system and the mechanical shaft system of the synchronous generator as the generalized coordinates based on the structure of the circuit system including the synchronous generator to be simulated; and convert the system differential equation into the port Hamiltonian form equation to obtain the simulation equation.

12. The system according to claim 11, wherein Specifically, the simulation module is configured to divide S time points in the interval between the initial moment and the target moment; calculate the weighted average slope and the weight coefficient corresponding to each time point; and calculate the simulation values of the electromagnetic transient state variables at the target moment by using the S-step Runge-Kutta algorithm based on the weighted average slope, the weight coefficient corresponding to each time point, and the values of the electromagnetic transient state variables at the initial moment.

13. The system according to claim 10, wherein The electromagnetic transient state variables include: the voltage of the circuit system, the node magnetic flux linkage of the circuit system, the mechanical angular velocity of the synchronous generator, and the mechanical angular displacement of the synchronous generator.

14. The system according to claim 12, wherein The expression of the S-step Runge-Kutta algorithm is as follows: where x h is the simulated value of the electromagnetic transient state variable x at the target time, x0 is the value of the electromagnetic transient state variable x at the initial time, h is the time step, and b j is the weight coefficient, k j is the weighted average slope, s is the number of steps corresponding to the number of time points, j = 1, 2, …, s; the x0 and h satisfy the following formula: where M, P, Q, z, N, V are coefficient matrices, and k i is the slope a of each point ij is the weight coefficient, and u is the input vector.

15. The system according to claim 14, wherein The expression of the coefficient matrix M is as follows: where diag is a diagonal matrix, is the coefficient matrix of the inductor branch of the circuit system, J is the inertia matrix of the mechanical shaft system, and K is the stiffness matrix of the mechanical shaft system; The expression of the coefficient matrix N is as follows: N = diag(I4, 0, I6, 0, 1), where I4 and I6 are the node injection current source vectors; The expression of the coefficient matrix V is as follows: V = S = W = 0, where S and W are coefficient matrices; The expression of the coefficient matrix P is as follows: Among them, is the coefficient matrix of the inductive branch of the circuit system, and K is the stiffness matrix of the mechanical shafting; The expression of the coefficient matrix z is as follows: Among them, is the magnetic flux linkage value of the circuit system, is the coefficient matrix of the inductor branch of the circuit system, is the inverse matrix of the inductance coefficient used to calculate the magnetic field energy stored in the synchronous generator, is the magnetic flux linkage vector, is the first derivative of the mechanical angular displacement, K is the stiffness matrix of the mechanical shafting, and θ is the mechanical angular displacement, is the magnetic flux linkage vector, is the electromagnetic torque of the synchronous generator, and x is the electromagnetic transient state variable; The expression of the coefficient matrix Q is as follows: Among them, is the coefficient matrix of the resistance branch of the circuit system, and D is the coefficient matrix of the friction loss of the mechanical shafting.

16. The system according to claim 14 or 15, characterized in that The weight coefficient a ij has the following expression: The weight coefficient b j has the following expression: where l j (τ) satisfies γ j , γ l , γ i are real numbers, s is the number of steps corresponding to the number of time points, l = 1, 2, …, s; The weighted average slope k j has the following expression: Among them, is the electromagnetic transient state quantity parameter, t0 is the initial moment, and γ j is a real number, and h is the time step.

17. The system according to claim 10, wherein, It further includes: An error calculation module, configured to calculate whether the error between the simulation values and the theoretical values of the electromagnetic transient state variables meets the set error range.

18. The system according to claim 17, wherein The expression for the error between the simulation values and the theoretical values of the electromagnetic transient state variables meeting the set error range is as follows: in, t n The theoretical value of the magnetic flux of the circuit system at the moment, t n The magnetic flux simulation value of the circuit system at the moment; t n The theoretical value of the mechanical angular velocity of the synchronous generator of the circuit system at the moment, t n The mechanical angular velocity simulation value of the synchronous generator of the circuit system at the moment; θ n t n The theoretical value of the mechanical angular displacement of the synchronous generator of the circuit system at the moment, θ(t n ) is t n Mechanical angular displacement simulation value of the synchronous generator of the instantaneous circuit system; t n The theoretical voltage value of the circuit system at this moment, t n The voltage simulation value of the circuit system at time t n =nh≤T m ,h is the time step, T m is a constant that is independent of h; is the set error range, and s is the number of steps corresponding to the number of time points.

19. A computer device, characterized in that, It includes: One or more processors; The processor is configured to store one or more programs; When the one or more programs are executed by the one or more processors, the electromagnetic transient simulation method for a circuit system including a synchronous generator 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 electromagnetic transient simulation method for a circuit system including a synchronous generator according to any one of claims 1 to 9 is implemented.

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