A simulation method, device and equipment of a flexible excitation device and a storage medium

Abstract

The application belongs to the field of electric power, and discloses a simulation method, device and equipment of a flexible excitation device and a storage medium, which comprises the following steps: constructing a flexible excitation simulation model, wherein the flexible excitation simulation model at least comprises a voltage transmission and load compensation unit, a series correction unit, a voltage regulation and amplification unit, a limiting amplitude unit and a parallel correction unit connected in series, and the parallel correction unit is connected in parallel with the voltage regulation and amplification unit; in a voltage regulator limiting amplitude module of the limiting amplitude unit, the upper limit and the lower limit of the output of the voltage regulator contained in the limiting amplitude unit are adjusted according to the comparison result of the terminal voltage and the preset inflection point voltage, so as to simulate the strong excitation capability of the flexible excitation device under low voltage working conditions and the peak voltage decoupling characteristics under overvoltage working conditions; in an excitation current over-limit limiting amplitude module of the limiting amplitude unit, the excitation current over-limit limiting amplitude value is calculated according to the terminal voltage and the excitation current, so as to simulate the overcurrent limiting function of the power device in the flexible excitation device.

Description

Technical Field

[0001] This invention belongs to the field of electric power, and particularly relates to a simulation method, apparatus, equipment and storage medium for a flexible excitation device. Background Technology

[0002] Synchronous generators are the cornerstone of stable power system operation. With the large-scale grid connection of new energy sources such as wind power and photovoltaics, their weak support and disturbance immunity pose challenges to grid stability, thus placing higher demands on the dynamic performance of synchronous generators. Flexible excitation systems using IGBTs (Insulated Gate Bipolar Transistors) as power unit carriers have broken through the output limitation of traditional thyristor-based excitation systems, where the peak voltage is proportional to the terminal voltage. This effectively improves the excitation capability of synchronous generators under low-voltage conditions and their ability to suppress overvoltage after faults, leading to their increasingly widespread application in new power systems.

[0003] In related technologies, excitation system simulation models are all based on conventional thyristor excitation systems. Their model structures (such as the IEEE standard model) and parameter characteristics cannot accurately simulate the core operational characteristics of flexible excitation systems, especially the decoupling characteristics between the peak voltage and the terminal voltage, as well as the rapid overcurrent limiting characteristics. This results in the inability to correctly assess the positive impact of flexible excitation devices on system stability in power grid simulation calculations, increasing power grid operation risks and construction investment. Summary of the Invention

[0004] In view of this, the present invention discloses a simulation method, apparatus, equipment and storage medium for a flexible excitation device, which can solve the shortcomings of related technologies.

[0005] To achieve the above objectives, the present invention discloses the following technical solution:

[0006] According to a first aspect of the present invention, a simulation method for a flexible excitation device is provided, the method comprising:

[0007] A flexible excitation simulation model is constructed to simulate the operation of a flexible excitation device. The flexible excitation simulation model includes at least a voltage transmitter and load compensation unit, a series correction unit, a voltage regulating amplifier unit, a limiting unit, and a parallel correction unit connected in parallel with the voltage regulating amplifier unit, which are connected in series in sequence. The inputs of the flexible excitation simulation model are the terminal voltage and the terminal current.

[0008] In the voltage regulator limiting module of the limiting unit, the upper and lower limits of the output of the voltage regulator included in the limiting unit are adjusted according to the comparison result between the terminal voltage and the preset inflection point voltage, so as to simulate the strong excitation capability of the flexible excitation device under low voltage conditions and the peak voltage decoupling characteristics under overvoltage conditions.

[0009] In the excitation current over-limiting module of the limiting unit, the excitation current over-limiting value is calculated based on the terminal voltage and excitation current to simulate the overcurrent limiting function of power devices in the flexible excitation device.

[0010] As a preferred embodiment, adjusting the upper and lower limits of the output of the voltage regulator included in the limiting unit based on the comparison result between the terminal voltage and the preset inflection point voltage includes:

[0011] Determine the gain coefficient corresponding to the preset inflection point voltage;

[0012] When the terminal voltage is not higher than the inflection point voltage, the product of the maximum output of the voltage regulator and the gain coefficient is determined as the upper limit of the voltage regulator, and the product of the minimum output of the voltage regulator and the gain coefficient is determined as the lower limit of the voltage regulator.

[0013] When the terminal voltage is higher than the inflection point voltage, the upper and lower limits of the voltage regulator are maintained at the maximum and minimum outputs of the voltage regulator, respectively.

[0014] As a preferred embodiment, the calculation of the excitation current over-limit value based on the terminal voltage and excitation current includes:

[0015] Determine the excitation current and the excitation current over-limit factor;

[0016] The excitation current over-limit value is determined by calculating the ratio of the product of the terminal voltage and the excitation current over-limit factor to the excitation current, and the output of the voltage regulating amplifier unit is constrained by the excitation current over-limit value.

[0017] As a preferred embodiment, the execution process of the voltage transmitter and load compensation unit includes:

[0018] The internal output voltage is calculated based on the generator terminal voltage vector, the generator terminal current vector, the droop resistor, and the droop reactance.

[0019] The internal output voltage is processed through a first-order inertial measurement circuit, and the measured voltage value is output to the series correction unit.

[0020] As a preferred embodiment, the series correction unit is implemented using a series PID controller or a parallel PID controller;

[0021] When a series PID controller is used, its transfer function includes the regulator gain, proportional-integral selection factor and multiple voltage regulator time constants, and is limited by the regulator's maximum / minimum internal voltage.

[0022] When a parallel PID controller is used, its output is the sum of the proportional, integral, and derivative outputs; the integral output is limited by the upper / lower integral limit, and the derivative output is limited by the upper / lower derivative limit.

[0023] As a preferred embodiment, the method further includes:

[0024] In the solution steps of the differential equations of each unit in the flexible excitation simulation model, the trapezoidal integral method is used to discretize and solve the differential equations describing the dynamic characteristics of each unit.

[0025] As a preferred embodiment, the method for obtaining the operating parameters of each unit in the flexible excitation simulation model includes on-site measurement and system identification, including:

[0026] To keep the excitation regulator of the flexible excitation device in a static working state;

[0027] A series of step voltage disturbance signals of different amplitudes are applied to the input terminal of the excitation regulator;

[0028] The output response of each unit in the flexible excitation simulation model under the step voltage disturbance was measured and recorded simultaneously.

[0029] The measurement data is analyzed and verified using a combination of segmented identification and overall verification.

[0030] For linear dynamic elements in the model, the frequency domain measurement method or the time domain measurement method is used for parameter identification.

[0031] For the nonlinear components in the model, the least squares method is used to fit the parameters based on the test curves recorded in the output response to determine the operating parameters of each limiting module in the limiting unit.

[0032] According to a second aspect of the present invention, a simulation device for a flexible excitation device is provided, the system comprising:

[0033] Construction Unit: Constructs a flexible excitation simulation model for simulating the operation of a flexible excitation device. The flexible excitation simulation model includes at least a voltage transmitter and load compensation unit, a series correction unit, a voltage regulating amplifier unit, a limiting unit, and a parallel correction unit connected in parallel with the voltage regulating amplifier unit, all connected in series. The inputs of the flexible excitation simulation model are the terminal voltage and the terminal current.

[0034] Adjustment unit: In the voltage regulator limiting module of the limiting unit, the upper and lower limits of the output of the voltage regulator included in the limiting unit are adjusted according to the comparison result between the terminal voltage and the preset inflection point voltage, so as to simulate the strong excitation capability of the flexible excitation device under low voltage conditions and the peak voltage decoupling characteristics under overvoltage conditions.

[0035] First calculation unit: In the excitation current over-limiting module of the limiting unit, the excitation current over-limiting value is calculated based on the terminal voltage and excitation current to simulate the overcurrent limiting function of power devices in the flexible excitation device.

[0036] As a preferred embodiment, the adjustment unit is specifically used for:

[0037] Determine the gain coefficient corresponding to the preset inflection point voltage;

[0038] When the terminal voltage is not higher than the inflection point voltage, the product of the maximum output of the voltage regulator and the gain coefficient is determined as the upper limit of the voltage regulator, and the product of the minimum output of the voltage regulator and the gain coefficient is determined as the lower limit of the voltage regulator.

[0039] When the terminal voltage is higher than the inflection point voltage, the upper and lower limits of the voltage regulator are maintained at the maximum and minimum outputs of the voltage regulator, respectively.

[0040] As a preferred embodiment, the first computing unit is specifically used for:

[0041] Determine the excitation current and the excitation current over-limit factor;

[0042] The excitation current over-limit value is determined by calculating the ratio of the product of the terminal voltage and the excitation current over-limit factor to the excitation current, and the output of the voltage regulating amplifier unit is constrained by the excitation current over-limit value.

[0043] As a preferred embodiment, the execution process of the voltage transmitter and load compensation unit includes:

[0044] The second calculation unit calculates the internal output voltage based on the generator terminal voltage vector, the generator terminal current vector, the droop resistor, and the droop reactance.

[0045] Processing unit: The internal output voltage is processed through a first-order inertial measurement circuit, and the measured voltage value is output to the series correction unit.

[0046] As a preferred embodiment, the series correction unit is implemented using a series PID controller or a parallel PID controller;

[0047] When a series PID controller is used, its transfer function includes the regulator gain, proportional-integral selection factor and multiple voltage regulator time constants, and is limited by the regulator's maximum / minimum internal voltage.

[0048] When a parallel PID controller is used, its output is the sum of the proportional, integral, and derivative outputs; the integral output is limited by the upper / lower integral limit, and the derivative output is limited by the upper / lower derivative limit.

[0049] As a preferred embodiment, the device further includes:

[0050] Solution Unit: In the solution steps of the differential equations of each unit in the flexible excitation simulation model, the trapezoidal integral method is used to discretize and solve the differential equations describing the dynamic characteristics of each unit.

[0051] As a preferred embodiment, the method for obtaining the operating parameters of each unit in the flexible excitation simulation model includes on-site measurement and system identification, including:

[0052] To keep the excitation regulator of the flexible excitation device in a static working state;

[0053] A series of step voltage disturbance signals of different amplitudes are applied to the input terminal of the excitation regulator;

[0054] The output response of each unit in the flexible excitation simulation model under the step voltage disturbance was measured and recorded simultaneously.

[0055] The measurement data is analyzed and verified using a combination of segmented identification and overall verification.

[0056] For linear dynamic elements in the model, the frequency domain measurement method or the time domain measurement method is used for parameter identification.

[0057] For the nonlinear components in the model, the least squares method is used to fit the parameters based on the test curves recorded in the output response to determine the operating parameters of each limiting module in the limiting unit.

[0058] According to a third aspect of the present invention, an electronic device is provided, comprising:

[0059] processor;

[0060] Memory used to store processor-executable instructions;

[0061] The processor implements the steps of the method as described in the first aspect by running the executable instructions.

[0062] According to a fourth aspect of the invention, a computer-readable storage medium is provided having computer instructions stored thereon that, when executed by a processor, implement the steps of the method as described in the first aspect.

[0063] As can be seen from the above technical solutions, the simulation method of the flexible excitation device disclosed in this invention is as follows:

[0064] On the one hand, it can accurately simulate the operating characteristics of flexible excitation devices in electromechanical transient and medium-to-long-term dynamic processes, especially the dynamic characteristics of the peak voltage, effectively improving the credibility of the simulation and providing a guarantee for the construction of a new power system based on new energy sources. On the other hand, it can correctly reflect the strong excitation capability of the excitation voltage of the flexible excitation device under low-voltage conditions, as well as the decoupling characteristics of the excitation voltage and the generator terminal voltage when the generator terminal voltage is higher than the inflection point voltage. The comparison of the generator terminal voltage also shows that the generator terminal voltage simulated by this method can output a higher voltage under the strong excitation of the excitation device under low-voltage conditions, while improving the overvoltage suppression capability. Attached Figure Description

[0065] Figure 1 This is a flowchart illustrating a simulation method for a flexible excitation device, provided in an exemplary embodiment.

[0066] Figure 2 This is an exemplary embodiment of a simulation system for a flexible excitation device.

[0067] Figure 3 This is a block diagram of a voltage transmitter and load compensation unit provided in an exemplary embodiment;

[0068] Figure 4 This is an exemplary embodiment of a cascaded PID block diagram;

[0069] Figure 5 This is an exemplary embodiment of a parallel PID block diagram;

[0070] Figure 6 This is a block diagram of a voltage regulating amplifier unit provided in an exemplary embodiment;

[0071] Figure 7 This is a block diagram of a parallel correction unit provided in an exemplary embodiment;

[0072] Figure 8 This is an exemplary embodiment of a low-excitation limiting block diagram;

[0073] Figure 9 This is an exemplary embodiment of an overexcitation limiting block diagram;

[0074] Figure 10 This is a schematic structural diagram of a device provided in an exemplary embodiment;

[0075] Figure 11 This is a block diagram of a simulation device for a flexible excitation device provided in an exemplary embodiment. Detailed Implementation

[0076] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with one or more embodiments of the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of one or more embodiments of the present invention as detailed in the appended claims.

[0077] It should be noted that the steps of the corresponding methods in other embodiments are not necessarily performed in the order shown and described in this invention. In some other embodiments, the methods may include more or fewer steps than those described in this invention. Furthermore, a single step described in this invention may be broken down into multiple steps in other embodiments; and multiple steps described in this invention may be combined into a single step in other embodiments.

[0078] To further illustrate the present invention, the following embodiments are provided:

[0079] Synchronous generators are the cornerstone of stable power system operation. With the large-scale grid connection of new energy sources such as wind power and photovoltaics, their weak support and disturbance immunity pose challenges to grid stability, thus placing higher demands on the dynamic performance of synchronous generators. Flexible excitation systems using IGBTs (Insulated Gate Bipolar Transistors) as power unit carriers have broken through the output limitation of traditional thyristor-based excitation systems, where the peak voltage is proportional to the terminal voltage. This effectively improves the excitation capability of synchronous generators under low-voltage conditions and their ability to suppress overvoltage after faults, leading to their increasingly widespread application in new power systems.

[0080] In related technologies, excitation system simulation models are all based on conventional thyristor excitation systems. Their model structures (such as the IEEE standard model) and parameter characteristics cannot accurately simulate the core operational characteristics of flexible excitation systems, especially the decoupling characteristics between the peak voltage and the terminal voltage, as well as the rapid overcurrent limiting characteristics. This results in the inability to correctly assess the positive impact of flexible excitation devices on system stability in power grid simulation calculations, increasing power grid operation risks and construction investment.

[0081] To address the shortcomings in related technologies, this invention proposes a simulation method for a flexible excitation device.

[0082] Figure 1 This is a flowchart illustrating a simulation method for a flexible excitation device, as provided in an exemplary embodiment. Figure 1 As shown, the method may include the following steps:

[0083] Step 101: Construct a flexible excitation simulation model for simulating the operation of a flexible excitation device. The flexible excitation simulation model includes at least a voltage transmitter and load compensation unit, a series correction unit, a voltage regulating amplifier unit, a limiting unit, and a parallel correction unit connected in parallel with the voltage regulating amplifier unit, all connected in series. The inputs of the flexible excitation simulation model are the terminal voltage and the terminal current.

[0084] Step 102: In the voltage regulator limiting module of the limiting unit, the upper and lower limits of the output of the voltage regulator included in the limiting unit are adjusted according to the comparison result between the terminal voltage and the preset inflection point voltage, so as to simulate the strong excitation capability of the flexible excitation device under low voltage conditions and the peak voltage decoupling characteristics under overvoltage conditions.

[0085] Step 103: In the excitation current over-limiting module of the limiting unit, the excitation current over-limiting value is calculated based on the terminal voltage and excitation current to simulate the overcurrent limiting function of the power device in the flexible excitation device.

[0086] In this embodiment, on the one hand, the operating characteristics of the flexible excitation device in electromechanical transient and medium-to-long-term dynamic processes can be accurately simulated, especially the dynamic characteristics of the peak voltage, effectively improving the credibility of the simulation and providing a guarantee for the construction of a new power system based on new energy sources. On the other hand, it can correctly reflect the strong excitation capability of the excitation voltage of the flexible excitation device under low-voltage conditions, and the decoupling characteristics of the excitation voltage and the generator terminal voltage when the generator terminal voltage is higher than the inflection point voltage. The comparison of the generator terminal voltage also shows that the generator terminal voltage simulated by this method can output a higher voltage under the strong excitation of the excitation device under low-voltage conditions, while improving the overvoltage suppression capability.

[0087] Figure 2 This is an exemplary embodiment of a simulation system for a flexible excitation device. (See diagram below.) Figure 2 As shown, the system includes: a voltage transmitter and load compensation unit, a series correction unit, a voltage regulating amplifier unit, a parallel correction unit, and a limiting unit.

[0088] In one embodiment, the execution process of the voltage transmitter and load compensation unit includes: calculating the internal output voltage based on the generator terminal voltage vector, the generator terminal current vector, the droop resistor, and the droop reactance; processing the internal output voltage through a first-order inertial measurement circuit, and outputting the measured voltage value to the series correction unit.

[0089] The voltage transmitter and load compensation unit is used to calculate the compensation voltage based on the generator terminal voltage vector and terminal current vector, and performs delay smoothing processing through a first-order inertial element.

[0090] The compensation voltage can be calculated as follows:

[0091] ;

[0092] in, For terminal voltage vector, R is the terminal current vector. C For the differential resistor, X C For differential reactance, This is the internal output of the voltage transmitter and load compensation unit.

[0093] The measurement process uses V C As the input, its delay and smoothing effect can be simulated using a first-order inertial approximation, with typical values ​​of 0.01s or 0.02s. The overall process is as follows: Figure 3 As shown, in Figure 3 In the middle, T R To measure the time constant of the inertial element, S is the integration factor, and V REF V is the excitation reference voltage. ERR This is the output for the deviation.

[0094] The series correction unit is used to perform PID correction on the compensation voltage.

[0095] The series correction unit can correct the compensation voltage output by the voltage transmitter and load compensation unit to improve the stability of the overall control. Specifically, it can be simulated by series PID or parallel PID.

[0096] The block diagram of the series PID control is as follows Figure 4 As shown, Figure 4 In the middle, V S K is the output of the power system stabilizer, and K is the regulator gain. V For proportional-integral or pure-integral adjustment selection factor (when K) V When the value is 0, it switches to parallel PI control. T1, T2, T3, T4 are the voltage regulator time constants, V. PIDO This is the PID output.

[0097] The block diagram of parallel PID control is as follows: Figure 5 As shown, Figure 5 In the middle, K P For proportional gain, K I For integral gain, K D T is the differential coefficient. D V is the differential time constant. INVMAX V is the upper limit of integration. INVMIN V is the lower limit of integration. DEVMAX V is the upper limit of the differential. DEVMIN This is the lower limit of the differential.

[0098] The voltage-regulating amplification unit is used to extract the AC component of the voltage-regulating amplification output.

[0099] Based on the output control of series and parallel correction units, a single-stage differential amplification is used, typically a pure proportional element. In practical engineering, a first-order inertial element can be added to improve control stability. The control block diagram is shown below. Figure 6 As shown, Figure 6 In the middle, V F For the output of the parallel correction unit, K A For the voltage regulator gain, T A V is the time constant of the voltage regulator amplifier. AMAX V is the upper limit of the voltage regulator's internal output. AMIN This is the lower limit of the voltage regulator's internal output.

[0100] The parallel correction unit is used to provide feedback excitation voltage based on the DC blocking link.

[0101] In one embodiment, the series correction unit is implemented using a series PID controller or a parallel PID controller. When a series PID controller is used, its transfer function includes the regulator gain, proportional-integral selection factor, and multiple voltage regulator time constants, and is limited by the regulator's maximum / minimum internal voltage. When a parallel PID controller is used, its output is the sum of the proportional, integral, and derivative channel outputs. The integral channel output is limited by the integral upper / lower limit, and the derivative channel output is limited by the derivative upper / lower limit.

[0102] The parallel correction unit uses the output of the voltage regulating amplifier unit as input and takes the AC quantity therein as feedback to improve control stability. It is typically simulated using a DC blocking element, and the control block diagram is shown below. Figure 7 As shown, Figure 7 In the middle, K F Parallel correction circuit gain, T F The time constant of the parallel correction circuit.

[0103] The limiting unit is used to limit the output of the feedback excitation voltage. The limiting includes: under-excitation limiting, over-excitation limiting, voltage regulator limiting, and excitation current over-limit limiting.

[0104] When using full-process simulation, the medium- and long-term dynamic characteristics of the generator must be considered, and under-excitation and over-excitation control must be taken into account. Therefore, the limiting unit consists of four parts: under-excitation limiting, over-excitation limiting, excitation current over-limit limiting, and voltage regulator limiting.

[0105] Low excitation limiting control block diagram as follows Figure 8 As shown, Figure 8 In this context, P represents the generator's active power output, Q represents the generator's reactive power output, and K... H1 For the low excitation limiting circuit gain, T H1 T H2 V is the time constant of the low-excitation limiting circuit. H This is for low-excitation, limited-amplitude output.

[0106] The overexcitation limiting control block diagram is as follows: Figure 9 As shown, Figure 9 In the figure, B represents the allowable over-excitation heat generation value, and T represents the heat generation value. L1 T L2 V is the time constant of the low-excitation limiting circuit. L For overexcitation limiting output, I FDN This refers to the long-term allowable current for the generator's magnetic field.

[0107] Voltage regulator limiting: Flexible excitation utilizes the self-excited boosting capability of the voltage source converter to overcome the output limitation that the peak voltage of the thyristor excitation system is proportional to the terminal voltage.

[0108] In one embodiment, adjusting the upper and lower limits of the output of the voltage regulator included in the limiting unit based on the comparison result between the terminal voltage and the preset inflection point voltage includes: determining the gain coefficient corresponding to the preset inflection point voltage; when the terminal voltage is not higher than the inflection point voltage, determining the product of the maximum output of the voltage regulator and the gain coefficient as the upper limit of the voltage regulator, and determining the product of the minimum output of the voltage regulator and the gain coefficient as the lower limit of the voltage regulator; when the terminal voltage is higher than the inflection point voltage, the upper and lower limits of the voltage regulator are maintained as the maximum and minimum outputs of the voltage regulator, respectively.

[0109] When the terminal voltage is lower than the set value, it has better excitation capability; when it is higher than this value, the peak voltage remains unchanged, and the following formula is used for simulation:

[0110] ;

[0111] Among them, K FLEX V represents the gain corresponding to the flexible excitation inflection point voltage. RMAX V is the maximum output value of the voltage regulator. RMIN V is the minimum output value of the voltage regulator. KEEN E is the preset inflection point voltage. FDLH E is the upper limit of the voltage regulator. FDLL This is the lower limit of the voltage regulator's limit.

[0112] Excitation current over-limit limiting: When the excitation current exceeds the limit, the output limit is directly changed to ensure that the IGBT does not overcurrent.

[0113] In one embodiment, calculating the excitation current over-limit value based on the terminal voltage and excitation current includes: determining the excitation current and the excitation current over-limit coefficient; determining the excitation current over-limit value by calculating the ratio of the product of the terminal voltage and the excitation current over-limit coefficient to the excitation current; and constraining the output of the voltage regulating amplifier unit by the excitation current over-limit value.

[0114] The limiting is directly proportional to the terminal voltage and inversely proportional to the excitation current, and is simulated using the following formula.

[0115] ;

[0116] Among them, E FDL To limit the excitation current beyond the limit, K LIMIT I is the excitation current over-limit limiting factor. FD This is the excitation current.

[0117] The output of the voltage regulating amplifier unit is compared with: (1) the under-excitation limit and the larger one is selected; (2) the over-excitation limit and the smaller one is selected; (3) the voltage regulating amplifier output limit EFDLH and EFDLL must not be exceeded; (4) the excitation current limit must not be exceeded.

[0118] In one embodiment, the method further includes: in the step of solving the differential equations of each unit in the flexible excitation simulation model, using the trapezoidal integral method to discretize and solve the differential equations describing the dynamic characteristics of each unit.

[0119] In one embodiment, the method for obtaining the operating parameters of each unit in the flexible excitation simulation model includes on-site measurement and system identification, including: putting the excitation regulator of the flexible excitation device in a static working state; applying a series of step voltage disturbance signals of different amplitudes to the input terminal of the excitation regulator; synchronously measuring and recording the output response of each unit in the flexible excitation simulation model under the step voltage disturbance; and analyzing and verifying the measurement data by combining segment identification and overall verification: for linear dynamic links in the model, parameter identification is performed using frequency domain measurement or time domain measurement; for nonlinear links in the model, parameter fitting is performed using the least squares method based on the test curves recorded in the output response to determine the operating parameters of each limiting module in the limiting unit.

[0120] Figure 10 This is a schematic structural diagram of a device provided in an exemplary embodiment. Please refer to... Figure 10At the hardware level, the device includes a processor 1002, an internal bus 1004, a network interface 1006, memory 1008, and non-volatile memory 1010, and may also include other hardware required for its functions. One or more embodiments of the present invention can be implemented in software, for example, the processor 1002 reads the corresponding computer program from the non-volatile memory 1010 into the memory 1008 and then runs it. Of course, in addition to software implementation, one or more embodiments of the present invention do not exclude other implementation methods, such as logic devices or a combination of hardware and software, etc. That is to say, the execution subject of the following processing flow is not limited to each logic unit, but can also be hardware or logic devices.

[0121] Please refer to Figure 11 A simulation device for a flexible excitation device can be applied to, for example... Figure 11 The device shown, in order to implement the technical solution of the present invention, includes:

[0122] The construction unit 1101 is used to construct a flexible excitation simulation model for simulating the operation of a flexible excitation device. The flexible excitation simulation model includes at least a voltage transmitter and load compensation unit, a series correction unit, a voltage regulating amplifier unit, a limiting unit, and a parallel correction unit connected in parallel with the voltage regulating amplifier unit, which are connected in series in sequence. The inputs of the flexible excitation simulation model are the terminal voltage and the terminal current.

[0123] The adjustment unit 1102 is used to adjust the upper and lower limits of the output of the voltage regulator included in the limiting unit according to the comparison result between the terminal voltage and the preset inflection point voltage in the voltage regulator limiting module of the limiting unit, so as to simulate the strong excitation capability of the flexible excitation device under low voltage conditions and the peak voltage decoupling characteristics under overvoltage conditions.

[0124] The first calculation unit 1103 is used to calculate the excitation current over-limit value based on the terminal voltage and excitation current in the excitation current over-limit module of the limiting unit, so as to simulate the overcurrent limiting function of the power device in the flexible excitation device.

[0125] Optionally, the adjustment unit 1102 is specifically used for:

[0126] Determine the gain coefficient corresponding to the preset inflection point voltage;

[0127] When the terminal voltage is not higher than the inflection point voltage, the product of the maximum output of the voltage regulator and the gain coefficient is determined as the upper limit of the voltage regulator, and the product of the minimum output of the voltage regulator and the gain coefficient is determined as the lower limit of the voltage regulator.

[0128] When the terminal voltage is higher than the inflection point voltage, the upper and lower limits of the voltage regulator are maintained at the maximum and minimum outputs of the voltage regulator, respectively.

[0129] Optionally, the first computing unit 1103 is specifically used for:

[0130] Determine the excitation current and the excitation current over-limit factor;

[0131] The excitation current over-limit value is determined by calculating the ratio of the product of the terminal voltage and the excitation current over-limit factor to the excitation current, and the output of the voltage regulating amplifier unit is constrained by the excitation current over-limit value.

[0132] Optionally, the execution process of the voltage transmitter and load compensation unit includes:

[0133] The second calculation unit 1104 is used to calculate the internal output voltage based on the generator terminal voltage vector, the generator terminal current vector, the droop resistor, and the droop reactance.

[0134] The processing unit 1105 is used to process the internal output voltage through a first-order inertial measurement circuit and output the measured voltage value to the series correction unit.

[0135] Optionally, the series correction unit is implemented using a series PID controller or a parallel PID controller;

[0136] When a series PID controller is used, its transfer function includes the regulator gain, proportional-integral selection factor and multiple voltage regulator time constants, and is limited by the regulator's maximum / minimum internal voltage.

[0137] When a parallel PID controller is used, its output is the sum of the proportional, integral, and derivative outputs; the integral output is limited by the upper / lower integral limit, and the derivative output is limited by the upper / lower derivative limit.

[0138] Optionally, the device further includes:

[0139] The solver unit 1106 is used to discretize and solve the differential equations describing the dynamic characteristics of each unit in the solution steps of the differential equations of each unit in the flexible excitation simulation model by using the trapezoidal integral method.

[0140] Optionally, the method for obtaining the operating parameters of each unit in the flexible excitation simulation model includes on-site measurement and system identification, including:

[0141] To keep the excitation regulator of the flexible excitation device in a static working state;

[0142] A series of step voltage disturbance signals of different amplitudes are applied to the input terminal of the excitation regulator;

[0143] The output response of each unit in the flexible excitation simulation model under the step voltage disturbance was measured and recorded simultaneously.

[0144] The measurement data is analyzed and verified using a combination of segmented identification and overall verification.

[0145] For linear dynamic elements in the model, the frequency domain measurement method or the time domain measurement method is used for parameter identification.

[0146] For the nonlinear components in the model, the least squares method is used to fit the parameters based on the test curves recorded in the output response to determine the operating parameters of each limiting module in the limiting unit.

[0147] The systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer, which can take the form of a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email sending and receiving device, game console, tablet computer, wearable device, or any combination of these devices.

[0148] In a typical configuration, a computer includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0149] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0150] Computer-readable media, including both permanent and non-permanent, removable and non-removable media, can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, disk storage, quantum memory, graphene-based storage media or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0151] For any other form of computer-readable medium (or computer-readable storage medium) as described above, computer instructions may be stored thereon, which, when executed by a processor, implement one or more of the above embodiments, thereby realizing the technical solution of the present invention.

[0152] The present invention also proposes a computer program that, when executed by a processor, implements one or more of the embodiments described above, thereby realizing the technical solution of the present invention. This computer program may be specifically recorded on the above-described or other computer-readable media, and the present invention does not impose any limitations on this.

[0153] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0154] The foregoing has described specific embodiments of the invention. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired results. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0155] The terminology used in one or more embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” used in one or more embodiments of the invention and in the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0156] It should be understood that although the terms first, second, third, etc., may be used to describe various information in one or more embodiments of the present invention, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first information may also be referred to as second information without departing from the scope of one or more embodiments of the present invention, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to a determination."

[0157] The above description is merely a preferred embodiment of one or more embodiments of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments of the present invention should be included within the protection scope of one or more embodiments of the present invention.

Claims

1. A simulation method for a flexible excitation device, characterized in that, The method includes: A flexible excitation simulation model is constructed to simulate the operation of a flexible excitation device. The flexible excitation simulation model includes at least a voltage transmitter and load compensation unit, a series correction unit, a voltage regulating amplifier unit, a limiting unit, and a parallel correction unit connected in parallel with the voltage regulating amplifier unit, which are connected in series in sequence. The inputs of the flexible excitation simulation model are the terminal voltage and the terminal current. In the voltage regulator limiting module of the limiting unit, the upper and lower limits of the output of the voltage regulator included in the limiting unit are adjusted according to the comparison result between the terminal voltage and the preset inflection point voltage, so as to simulate the strong excitation capability of the flexible excitation device under low voltage conditions and the peak voltage decoupling characteristics under overvoltage conditions. In the excitation current over-limiting module of the limiting unit, the excitation current over-limiting value is calculated based on the terminal voltage and excitation current to simulate the overcurrent limiting function of power devices in the flexible excitation device.

2. The method according to claim 1, characterized in that, The step of adjusting the upper and lower limits of the output of the voltage regulator included in the limiting unit based on the comparison result between the terminal voltage and the preset inflection point voltage includes: Determine the gain coefficient corresponding to the preset inflection point voltage; When the terminal voltage is not higher than the inflection point voltage, the product of the maximum output of the voltage regulator and the gain coefficient is determined as the upper limit of the voltage regulator, and the product of the minimum output of the voltage regulator and the gain coefficient is determined as the lower limit of the voltage regulator. When the terminal voltage is higher than the inflection point voltage, the upper and lower limits of the voltage regulator are maintained at the maximum and minimum outputs of the voltage regulator, respectively.

3. The method according to claim 1, characterized in that, The calculation of the excitation current over-limit value based on the terminal voltage and excitation current includes: Determine the excitation current and the excitation current over-limit factor; The excitation current over-limit value is determined by calculating the ratio of the product of the terminal voltage and the excitation current over-limit factor to the excitation current, and the output of the voltage regulating amplifier unit is constrained by the excitation current over-limit value.

4. The method according to claim 1, characterized in that, The execution process of the voltage transmission and load compensation unit includes: The internal output voltage is calculated based on the generator terminal voltage vector, the generator terminal current vector, the droop resistor, and the droop reactance. The internal output voltage is processed through a first-order inertial measurement circuit, and the measured voltage value is output to the series correction unit.

5. The method according to claim 1, characterized in that, The series correction unit is implemented using a series PID controller or a parallel PID controller; When a series PID controller is used, its transfer function includes the regulator gain, proportional-integral selection factor and multiple voltage regulator time constants, and is limited by the regulator's maximum / minimum internal voltage. When a parallel PID controller is used, its output is the sum of the proportional, integral, and derivative outputs; the integral output is limited by the upper / lower integral limit, and the derivative output is limited by the upper / lower derivative limit.

6. The method according to claim 1, characterized in that, The method further includes: In the solution steps of the differential equations of each unit in the flexible excitation simulation model, the trapezoidal integral method is used to discretize and solve the differential equations describing the dynamic characteristics of each unit.

7. The method according to claim 1, characterized in that, The methods for obtaining the operating parameters of each unit in the flexible excitation simulation model include on-site measurement and system identification, including: To keep the excitation regulator of the flexible excitation device in a static working state; A series of step voltage disturbance signals of different amplitudes are applied to the input terminal of the excitation regulator; The output response of each unit in the flexible excitation simulation model under the step voltage disturbance was measured and recorded simultaneously. The measurement data is analyzed and verified using a combination of segmented identification and overall verification. For linear dynamic elements in the model, the frequency domain measurement method or the time domain measurement method is used for parameter identification. For the nonlinear components in the model, the least squares method is used to fit the parameters based on the test curves recorded in the output response to determine the operating parameters of each limiting module in the limiting unit.

8. A simulation device for a flexible excitation device, characterized in that, The device includes: Construction Unit: Constructs a flexible excitation simulation model for simulating the operation of a flexible excitation device. The flexible excitation simulation model includes at least a voltage transmitter and load compensation unit, a series correction unit, a voltage regulating amplifier unit, a limiting unit, and a parallel correction unit connected in parallel with the voltage regulating amplifier unit, all connected in series. The inputs of the flexible excitation simulation model are the terminal voltage and the terminal current. Adjustment unit: In the voltage regulator limiting module of the limiting unit, the upper and lower limits of the output of the voltage regulator included in the limiting unit are adjusted according to the comparison result between the terminal voltage and the preset inflection point voltage, so as to simulate the strong excitation capability of the flexible excitation device under low voltage conditions and the peak voltage decoupling characteristics under overvoltage conditions. First calculation unit: In the excitation current over-limiting module of the limiting unit, the excitation current over-limiting value is calculated based on the terminal voltage and excitation current to simulate the overcurrent limiting function of power devices in the flexible excitation device.

9. An electronic device, characterized in that, include: processor; Memory used to store processor-executable instructions; The processor implements the steps of the method as described in any one of claims 1-7 by running the executable instructions.

10. A computer-readable storage medium storing computer instructions thereon, characterized in that, When executed by the processor, this instruction implements the steps of the method as described in any one of claims 1-7.

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