Power electronization load modeling method, device and equipment considering converter and storage medium

Abstract

The invention relates to the technical field of power systems, and discloses a power electronization load modeling method, device and equipment considering a converter and a storage medium, and the method comprises the steps: obtaining a double-loop control strategy of a plurality of power electronization loads to be modeled; for each double-loop control strategy, determining a double-loop control structure of the converter based on the double-loop control strategy, and determining a critical voltage value based on the double-loop control structure; for each power electronic load, obtaining a preset protection delay and a preset protection voltage threshold value of a built-in converter; dividing load operation conditions of the power electronic load based on the preset protection delay, the preset protection voltage threshold and the critical voltage value, wherein the load operation conditions comprise a stable operation condition, a transient regulation condition and a protection condition; and constructing a total load model of the power electronic load based on the load operation condition and the common physical structure. A load model capable of accurately describing external performance of a load is established based on a load operation condition division mechanism in combination with a common physical structure.

Description

Technical Field

[0001] This disclosure relates to the field of power system technology, specifically to a power electronic load modeling method, apparatus, equipment, and storage medium considering converters. Background Technology

[0002] In the field of power system technology, power system stability analysis typically relies on simulation calculations, and the accuracy of these calculations is highly correlated with the accuracy of the load model used. Traditional load modeling usually employs a combined load model consisting of a static load model and an induction motor model, resulting in a fixed model structure.

[0003] However, with the widespread application of power electronic devices such as variable frequency air conditioners, LED lights, and electric vehicle charging facilities in production and daily life, the load on the distribution side of the power grid is showing a significant trend towards power electronics. Compared to traditional loads, when the power grid experiences voltage drops, phase angle changes, or frequency shifts, power electronic loads often undergo multi-stage mode changes from the linear control zone to the current-limiting control zone, and then to protection operation. If a traditional fixed-structure integrated load model is still used to simulate this type of power electronic load, it is difficult to reflect the nonlinear behavior of power electronic loads in the current-limiting control zone and protection operation mode, which can easily cause serious distortion of the load power response in the simulation, thereby affecting the reliability of power system stability analysis. Summary of the Invention

[0004] This disclosure addresses the problems existing in the prior art by providing a method, apparatus, device, and storage medium for power electronic load modeling that takes into account converters.

[0005] To achieve the above objectives, the technical solution adopted in this disclosure is as follows: A first aspect of this disclosure provides a method for modeling power electronic loads that takes into account a converter, comprising: acquiring dual-loop control strategies for multiple power electronic loads to be modeled, wherein the dual-loop control strategies are used to describe the dual-loop control structure of the converter; for each dual-loop control strategy, determining the dual-loop control structure of the converter based on the dual-loop control strategy, and determining a critical voltage value based on the dual-loop control structure; for each power electronic load, acquiring a preset protection delay and a preset protection voltage threshold of the converter built into it; classifying the load operating conditions of the power electronic load based on the preset protection delay, the preset protection voltage threshold, and the critical voltage value, wherein the load operating conditions include a stable operating condition, a transient regulation condition, and a protection condition; and constructing a total load model of the power electronic load based on the load operating conditions and common physical structures, wherein the common physical structures are the physical devices shared by the converters built into the multiple power electronic loads to be modeled, and the total load model includes sub-load models corresponding one-to-one with each operating condition.

[0006] In some embodiments of this disclosure, determining the critical voltage value based on the dual-loop control structure includes: obtaining engineering experience parameters corresponding to the dual-loop control structure, wherein the engineering experience parameters are used to represent the dynamic response boundary and stability margin of the power electronic load under stable operating conditions; and calculating the critical voltage value based on the engineering experience parameters and in combination with the rated electrical quantity of the power electronic load.

[0007] In some embodiments of this disclosure, the load operation conditions of the power electronic load are divided based on the preset protection delay, the preset protection voltage threshold, and the critical voltage value. These load operation conditions include stable operation conditions, transient regulation conditions, and protection conditions. Specifically, when the load terminal voltage is greater than the critical voltage value, the power electronic load is in the stable operation condition, indicating that the power electronic load is in a steady-state safe operation state under rated load. When the load terminal voltage is less than or equal to the critical voltage value and greater than the preset protection voltage threshold, or when the load terminal voltage is less than or equal to the preset protection voltage threshold... When the load terminal voltage is less than or equal to the preset protection voltage threshold, and the duration of the voltage at the load terminal being less than the preset protection delay is less than the preset protection delay, the power electronic load is in the transient regulation condition, which indicates that the power electronic load is in a state of dynamic response and regulation to external disturbances. When the load terminal voltage is less than or equal to the preset protection voltage threshold, and the duration of the voltage at the load terminal being less than or equal to the preset protection voltage threshold is greater than or equal to the preset protection delay, the power electronic load is in the protection condition, which indicates that the power electronic load is in a protection state with no ability to regulate external disturbances.

[0008] In some embodiments of this disclosure, constructing the total load model of the power electronic load based on the load operating conditions and the common physical structure includes: determining the common physical structure based on the converters built into the plurality of power electronic loads; obtaining the electrical quantity reference command equation set corresponding to the common physical structure; obtaining the load characteristic equation set corresponding to each operating condition in the load operating conditions, combined with the dual-loop control structure of the power electronic load, wherein the operating condition is any one of the stable operation condition, transient regulation condition, and protection condition; and constructing the total load model by combining the load characteristic equation set and the electrical quantity reference command equation set.

[0009] In some embodiments of this disclosure, obtaining the load characteristic equation set corresponding to the operating condition in conjunction with the dual-loop control structure of the power electronic load includes: if the operating condition is a transient regulation operating condition, then in conjunction with the dual-loop control structure of the power electronic load and based on the device type of the converter, obtaining the load characteristic equation set corresponding to the transient regulation operating condition, wherein the device type includes inverter, rectifier, DC-DC converter and AC-AC converter.

[0010] In some embodiments of this disclosure, the method further includes: for each power electronic load to be modeled, real-time monitoring of the real-time load terminal voltage of the power electronic load; counting the real-time duration of the real-time load terminal voltage that is continuously less than the preset protection voltage threshold; and determining the sub-load model corresponding to the power electronic load at the current moment from the total load model based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value.

[0011] In some embodiments of this disclosure, the method further includes: determining the real-time operating condition of the power electronic load based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value, wherein the real-time operating condition is any one of stable operation, transient regulation, and protection; and determining the sub-load model corresponding to the power electronic load at the next time moment from the total load model based on the real-time load terminal voltage, the real-time duration, the real-time operating condition, the preset protection delay, the preset protection voltage threshold, and the critical voltage value.

[0012] A second aspect of this disclosure discloses a power electronic load modeling device considering a converter, comprising: an acquisition unit for acquiring dual-loop control strategies of multiple power electronic loads to be modeled, wherein the dual-loop control strategies are used to describe the dual-loop control structure of the converter; a determination unit for determining the dual-loop control structure of the converter based on the dual-loop control strategies for each of the dual-loop control strategies, and determining a critical voltage value based on the dual-loop control structure; the acquisition unit is further configured to acquire, for each power electronic load, the preset protection delay and preset protection time of the converter built into it. The system includes: a protection voltage threshold; a division unit, used to divide the load operation conditions of the power electronic load based on the preset protection delay, the preset protection voltage threshold, and the critical voltage value, wherein the load operation conditions include stable operation conditions, transient regulation conditions, and protection conditions; and a construction unit, used to construct a total load model of the power electronic load based on the load operation conditions and common physical structures, wherein the common physical structures are the physical devices shared by the converters built into the multiple power electronic loads to be modeled, and the total load model includes sub-load models corresponding one-to-one with each operation condition.

[0013] This disclosure also provides an electronic device, comprising: a memory for storing at least one instruction; and a processor for invoking the instruction stored in the memory to execute the power electronic load modeling method considering the converter in the first aspect and any embodiment thereof.

[0014] This disclosure also provides a computer-readable storage medium storing at least one executable instruction, which is loaded and executed by a processor to implement the power electronic load modeling method for considering converters in the first aspect and any embodiment of the first aspect described above.

[0015] This disclosure also provides a computer program product, which includes: computer program code, which, when executed by a computer, causes the computer to perform the power electronic load modeling method considering the converter in the first aspect and any embodiment of the first aspect described above.

[0016] Compared with the prior art, this disclosure has the following beneficial effects: This scheme identifies the dual-loop control structure of electronically powered loads and scientifically determines the critical voltage value accordingly. Simultaneously, it combines the inherent preset protection delay and protection voltage threshold of the converter to construct a three-state operating condition classification mechanism (stable operation condition, transient regulation condition, and protection condition) based on voltage-time dual criteria. On this basis, it integrates the common physical structures of the converter (such as capacitors, filter inductors, power switches, etc.) with the dynamic characteristics of operating condition adaptation, establishing a load model with universality and operating condition adaptability. This load model can represent the true external performance of electronically powered loads under different operating conditions, effectively overcoming the distortion defects of traditional comprehensive load models under transient or protection conditions. It significantly improves the accuracy of the load model's external performance under different disturbance scenarios, thereby enhancing the accuracy and reliability of power system stability analysis based on this load model. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating a power electronic load modeling method considering converters according to an embodiment of this disclosure; Figure 2 This is a block diagram of a power electronic load modeling device for a converter, provided according to an embodiment of the present disclosure. Detailed Implementation

[0018] The present disclosure will now be further described with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present disclosure and should not be construed as limiting the scope of protection of the present disclosure. It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application.

[0019] The acquisition, transmission, storage, use, and processing of data in this disclosed technical solution comply with relevant national laws and regulations. In the embodiments of this disclosure, certain existing industry solutions such as software, components, and models may be mentioned. These should be considered exemplary, intended only to illustrate the feasibility of implementing the technical solution of this disclosure, and do not imply that the applicant has already used or necessarily used such solutions.

[0020] All terms used in this disclosure have the same meaning as understood by one of ordinary skill in the art to which this disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and not as idealized or highly formalized, unless expressly defined herein.

[0021] Example 1; The power electronic load modeling method considering converters in this embodiment can be applied to electronic devices with communication, computing, and data storage capabilities. Its specific process can be as follows: Figure 1As shown, it includes: Step 110: Obtain the dual-loop control strategy for multiple power electronic loads to be modeled, wherein the dual-loop control strategy is used to describe the dual-loop control structure of the converter.

[0022] In this context, "power electronic load" refers to electrical equipment connected to the power grid or power source via a converter, such as variable frequency air conditioners, LED lights, and electric vehicle charging facilities. A dual-loop control structure is a hierarchical feedback control architecture consisting of an outer loop controller (referred to as the outer loop) and an inner loop controller (referred to as the inner loop). The outer loop generates reference commands for the inner loop, while the inner loop enables rapid tracking of current or voltage. Specifically, the dual-loop control structure can be a voltage-current dual-loop, a power-current dual-loop, or a speed-current dual-loop. A converter is a power conversion device based on power electronic switching devices (such as IGBTs, MOSFETs, diodes, etc.) that can convert electrical energy from the power grid or power source into the electrical energy required by power electronic loads.

[0023] Step 120: For each of the dual-loop control strategies, determine the dual-loop control structure of the converter based on the dual-loop control strategy, and determine the critical voltage value based on the dual-loop control structure.

[0024] The converter in question is the built-in converter of the power electronic load corresponding to the dual-loop control strategy. The critical voltage value is a threshold value used to determine whether the converter or the power electronic load is in a steady-state safe operating state under rated load.

[0025] Specifically, in step 120 above, determining the critical voltage value based on the dual-loop control structure includes: obtaining the engineering experience parameters corresponding to the dual-loop control structure, wherein the engineering experience parameters are used to represent the dynamic response boundary and stability margin of the power electronic load under stable operating conditions; and calculating the critical voltage value based on the engineering experience parameters and in combination with the rated electrical quantity of the power electronic load.

[0026] Specifically, for the voltage-current dual-loop system, the engineering empirical parameters should at least include the ratio of the current saturation point to the rated current. For the power-current dual-loop system, the engineering empirical parameters should at least include the ratio of the power limit to the rated power. For the speed-current dual-loop system, the engineering empirical parameters should at least include the ratio of the current saturation point to the rated current and the ratio of the speed limit to the rated speed. Rated electrical quantities refer to the rated current, rated power, and rated speed of the power electronic load. It should be noted that the engineering empirical parameters here are for illustrative purposes only and are not specifically limited. Engineering empirical parameters can be added based on the actual situation where the critical voltage value can be calculated. For example, engineering empirical parameters may also include speed loop bandwidth, current loop bandwidth, voltage loop bandwidth, etc.

[0027] Furthermore, based on the engineering experience parameters and in conjunction with the rated electrical quantity of the power electronic load, the critical voltage value is calculated, including: using the product of the proportional coefficient in the engineering experience parameters and the rated electrical quantity as the limiting value; and using the ratio of the limiting value to the reference electrical quantity as the critical voltage value.

[0028] The limiting values ​​can be current limiting values, power limiting values, and speed limiting values. The reference electrical quantities refer to the reference current, reference power, and reference speed of the power electronic load.

[0029] For example, if the proportionality coefficient in the engineering experience parameter is the proportionality coefficient between the current saturation point and the rated current, then the rated electrical quantity is the rated current, the limiting value is the current limiting value, and the reference electrical quantity is the reference current; if the proportionality coefficient in the engineering experience parameter is the proportionality coefficient between the power limiting value and the rated power, then the rated electrical quantity is the rated power, the limiting value is the power limiting value, and the reference electrical quantity is the reference power; if the proportionality coefficient in the engineering experience parameter is the proportionality coefficient between the speed limiting value and the rated speed, then the rated electrical quantity is the rated speed, the limiting value is the speed limiting value, and the reference electrical quantity is the reference speed.

[0030] Therefore, based on engineering experience parameters, engineering experience parameters corresponding to the converter can be obtained. Furthermore, based on engineering experience parameters adapted to the converter, the critical voltage value matching the converter can be dynamically, specifically, and accurately determined. This makes the critical voltage value have equipment self-adaptive characteristics, greatly improving the accuracy of the critical voltage value. This further improves the accuracy of determining the load operating conditions of the converter or power electronic load, which is conducive to determining a more realistic load model.

[0031] Step 130: For each power electronic load, obtain the preset protection delay and preset protection voltage threshold of the built-in converter.

[0032] The preset protection delay and preset protection voltage threshold are used to determine whether the power electronic load is in a state where it cannot be adjusted for external disturbances. These preset protection delay and preset protection voltage threshold can be set by the manufacturer of the power electronic load or obtained from the load's equipment manual.

[0033] Step 140: Based on the preset protection delay, the preset protection voltage threshold, and the critical voltage value, classify the load operation conditions of the power electronic load. The load operation conditions include stable operation conditions, transient adjustment conditions, and protection conditions.

[0034] The term "load operation condition" indicates the operating state of the electronic load or converter. For example, "steady operation condition" indicates that the electronic load or converter is operating safely under rated load. "Transient regulation condition" indicates that the electronic load or converter is operating in a state of dynamic response and regulation to external disturbances. "Protection condition" indicates that the electronic load or converter is in a protection state where it has no ability to regulate external disturbances.

[0035] Specifically, in step 140 above, the division of the load operating conditions of the power electronic load based on the preset protection delay, the preset protection voltage threshold, and the critical voltage value includes a stable operating condition, a transient regulation condition, and a protection condition. Specifically, when the load terminal voltage is greater than the critical voltage value, the power electronic load is in the stable operating condition, which indicates that the power electronic load is in a steady-state safe operating state under rated load; when the load terminal voltage is less than or equal to the critical voltage value and greater than the preset protection voltage threshold, or when the load terminal voltage is less than or equal to the preset protection voltage threshold... When the voltage at the load terminal is less than the preset protection voltage threshold and the duration of the voltage at the load terminal is less than the preset protection delay, the power electronic load is in the transient regulation condition, which indicates that the power electronic load is in a state of dynamic response and regulation to external disturbances. When the voltage at the load terminal is less than or equal to the preset protection voltage threshold and the duration of the voltage at the load terminal is less than or equal to the preset protection voltage threshold is greater than or equal to the preset protection delay, the power electronic load is in the protection condition, which indicates that the power electronic load is in a protection state with no ability to regulate external disturbances.

[0036] Here, the load terminal voltage refers to the actual supply voltage sensed by the converter. Stable operation means the converter maintains stable output, and the load's static characteristics exhibit constant power characteristics. Transient regulation means the power electronic load is subjected to external disturbances (such as grid voltage drops, frequency shifts, load mutations, command switching, etc.). The converter, through its dual-loop controller, can dynamically adjust to these external disturbances to quickly restore the steady-state operating point within safe limits or provide auxiliary support functions. Protection mode means the power electronic load experiences severe external disturbances exceeding controllable limits (such as short-circuit faults, severe overvoltage, severe overcurrent, DC bus failure, etc.). The converter cannot regulate these severe external disturbances. To prevent damage to the power electronic load, the converter actively enters protection mode, stopping energy transmission and blocking the drive signals of power switching devices.

[0037] Therefore, based on the critical voltage value with equipment self-adaptive characteristics, combined with the preset protection delay and preset protection voltage threshold set by the equipment manufacturer or obtained from the equipment manual, the operating conditions of power electronic loads are refined and logically rigorously classified, significantly improving the accuracy and engineering applicability of load operating condition judgment for power electronic loads. This method effectively distinguishes three typical states—stable operation (normal steady-state operation), transient regulation (controllable dynamic response operation), and protection operation (uncontrollable fault isolation)—by dynamically comparing the load terminal voltage with the voltage critical value and the preset protection voltage threshold, and introducing a time dimension (preset protection delay) as a criterion. This avoids the coarse-grained assumption of "either stable or shut down" in traditional modeling. Thus, it not only provides a scientific and quantifiable basis for modeling the external characteristics of power electronic loads under different disturbance scenarios, but also enhances the realism of the load model's response to external disturbances (such as grid voltage fluctuations), thereby laying a more accurate and reliable technical foundation for applications such as power system stability analysis, fault ride-through capability assessment, and virtual power plant collaborative control.

[0038] Step 150: Based on the load operating conditions and the common physical structure, construct the total load model of the power electronic load. The common physical structure refers to the physical devices shared by the converters built into the multiple power electronic loads to be modeled. The total load model includes sub-load models that correspond one-to-one with each operating condition.

[0039] Among them, physical devices refer to electronic devices such as capacitors and inductors.

[0040] Specifically, in step 150 above, constructing the total load model of the power electronic load based on the load operating conditions and the common physical structure includes: determining the common physical structure based on the converters built into the multiple power electronic loads; obtaining the electrical quantity reference command equation set corresponding to the common physical structure; obtaining the load characteristic equation set corresponding to each operating condition in the load operating conditions, combined with the dual-loop control structure of the power electronic load, wherein the operating condition is any one of the stable operation condition, transient regulation condition, and protection condition; and constructing the total load model by combining the load characteristic equation set and the electrical quantity reference command equation set.

[0041] The electrical quantity reference command equation set can be either a voltage reference command equation set or a current reference command equation set. This set refers to the mathematical relationships that generate voltage or current reference commands in the converter control system based on the operating state of the power electronic load and external electrical quantities. The voltage / current reference command equations can be expressed in the form of d-axis and q-axis reference current in a synchronous rotating coordinate system, or in the form of equivalent current commands, power commands, or other equivalent control quantities; the specific form is not limited. The load characteristic equation set refers to a set of mathematical expressions describing the external performance (e.g., active power, reactive power, capacitor current) of the power electronic load under a specified load operating condition. The sub-load model is described by a new set of equations composed of the load characteristic equation set corresponding to the operating condition and the electrical quantity reference command equation set corresponding to that operating condition. The electrical quantity reference command equation set corresponding to the operating condition can be determined by judging the common judgment conditions of the operating condition and the electrical quantity reference command equation set. For example, these common judgment conditions can be the load terminal voltage and the critical voltage value, or other values; no specific restrictions are imposed here. The total load model is a general load model corresponding to a type of dual-loop control structure and a type of common physical structure. For example, the total load model is a general load model corresponding to a voltage-current dual-loop control structure and a capacitor.

[0042] For example, for a type of converter that includes capacitors, the corresponding current reference command equations can be found in the following set of equations: , in, This is the q-axis reference current; This is the voltage at the load terminal. This is the critical voltage value; This is the reactive power support ratio coefficient during the fault process.

[0043] It should be noted that the set of electrical quantity reference command equations is determined based on the common physical structure. This is only an example and is not a specific limitation. The set of electrical quantity reference command equations corresponding to the actual common physical structure can be determined.

[0044] For example, the load characteristic equations corresponding to stable operating conditions can be found in the following set of equations: , in, Represents the active power of electronically powered loads; Represents the reactive power of electronically powered loads; This indicates the initial active power of the power grid or power source to which the electronic load is connected; This indicates the initial reactive power of the power grid or power source to which the electronic load is connected.

[0045] For example, the load characteristic equations corresponding to the protection condition can be found in the following set of equations: , in, , The meaning of the symbol can be found in the preceding content.

[0046] Furthermore, the load characteristic equation set corresponding to the operating condition is obtained by combining the dual-loop control structure of the power electronic load, including: if the operating condition is a transient regulation operating condition, then the load characteristic equation set corresponding to the transient regulation operating condition is obtained by combining the dual-loop control structure of the power electronic load and based on the device type of the converter, wherein the device type includes inverter, rectifier, DC-DC converter and AC-AC converter.

[0047] For example, combining the dual-loop control structure of the power electronic load and based on the device type of the converter, the load characteristic equation set corresponding to the transient regulation condition is obtained, including: when the dual-loop control structure is a voltage-current dual-loop and the converter is a DC-DC converter or a rectifier, the first transient equation set is used as the load characteristic equation set corresponding to the transient regulation condition; when the dual-loop control structure is a voltage-current dual-loop and the converter is an AC-AC converter, the first transient equation set or the equivalent model equation set of the AC-AC converter is used as the load characteristic equation set corresponding to the transient regulation condition; when the dual-loop control structure is a voltage-current dual-loop and the converter is an inverter, the second transient equation set is used as the load characteristic equation set corresponding to the transient regulation condition.

[0048] The equivalent model equations of the AC-AC converter are determined based on the specific topology and control objectives of the AC-AC converter.

[0049] It should be noted that due to the different dual-loop control structures, the load characteristic equations for obtaining the external performance of the power electronic load are different. For ease of understanding, this scheme will take the voltage-current dual-loop control structure as an example for explanation.

[0050] For example, the first transient equation set is shown in the following equation set: , in, , , , , The meaning of the symbol can be found in the preceding content. Indicates capacitor current; This refers to the capacitors built into power electronic devices; The terminal voltage of the capacitor is represented by t; t is the differential operator with respect to the voltage. The voltage variation coefficient representing active power; The voltage variation coefficient representing reactive power; This represents the active power-frequency correlation coefficient; This represents the reactive power-frequency correlation coefficient; This indicates the change in frequency of the inverter compared to its current operating frequency and steady-state rated frequency. Indicates the power supply input current; This indicates the power input to the converter.

[0051] For example, the second transient equation set is shown in the following equation set: , in, , , , , , , ,t, , , , , , , , The meaning of the symbol can be found in the preceding content. This represents the reference value of the d-axis current output by the inverter; Indicates the proportionality coefficient of the outer ring, Indicates the integral coefficient of the outer ring; This indicates the reference voltage value for the capacitor.

[0052] Therefore, based on various load operating conditions (stable operation, transient regulation, and protection) and integrating the common physical structures of multiple power electronic loads' built-in converters (such as capacitors, filter inductors, and power switching devices), a total load model composed of general sub-load models adapted to different operating conditions is constructed. This achieves the abstraction from "individual equipment differences" to "common patterns of equipment groups," ensuring the physical consistency and response realism of the load model under different operating conditions, and significantly improving the modeling's universality, accuracy, and engineering practicality. It provides a reliable and accurate simulation load model for power system stability analysis.

[0053] In some examples, the method further includes: for each power electronic load to be modeled, real-time monitoring of the real-time load terminal voltage of the power electronic load; counting the real-time duration of the real-time load terminal voltage that is continuously lower than the preset protection voltage threshold; and determining the sub-load model corresponding to the power electronic load at the current moment from the total load model based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value.

[0054] Among them, the real-time load terminal voltage refers to the actual supply voltage sensed by the converter in real time, that is, the actual supply voltage sensed by the converter at the current moment.

[0055] Specifically, based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value, the sub-load model corresponding to the power electronic load at the current moment is determined from the total load model, including: determining the real-time operating condition corresponding to the power electronic load at the current moment based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value; and determining the sub-load model corresponding to the power electronic load at the current moment from the total load model based on the real-time operating condition.

[0056] The real-time operating condition refers to the load operating condition of the electronic load at the current moment. The real-time operating condition can be any one of the following: stable operation, transient regulation, or protection. Regarding how to determine the real-time operating condition of the electronic load at the current moment based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value, please refer to step 140 above, which details the classification of the electronic load's operating conditions based on the preset protection delay, the preset protection voltage threshold, and the critical voltage value. The detailed classification method for the load operating conditions, including stable operation, transient regulation, and protection, will not be elaborated further here. Here, the real-time duration refers to the duration during which the load terminal voltage is continuously lower than the preset protection voltage threshold in the detailed classification method for operating conditions in step 140 above.

[0057] Therefore, by obtaining the real-time load terminal voltage and real-time duration through real-time monitoring, and combining them with the total load model, the current load operating condition of the electronic load can be accurately determined. Based on the sub-load model corresponding to this load operating condition, the real-time external performance of the electronic load can be accurately represented, making the simulated electronic load sub-load model consistent with the actual electronic load, thus improving the accuracy of power system stability analysis based on the sub-load model.

[0058] In other examples, the method further includes: determining the real-time operating condition of the power electronic load based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value, wherein the real-time operating condition is any one of stable operation, transient regulation, and protection; and determining the sub-load model corresponding to the power electronic load at the next time moment from the total load model based on the real-time load terminal voltage, the real-time duration, the real-time operating condition, the preset protection delay, the preset protection voltage threshold, and the critical voltage value.

[0059] Among them, the real-time operating condition refers to the current operating condition of the power electronic load.

[0060] Specifically, based on the real-time load terminal voltage, the real-time duration, the real-time operating condition, the preset protection delay, the preset protection voltage threshold, and the critical voltage value, the sub-load model corresponding to the electronic load at the next moment from the current moment is determined from the total load model. This includes: when the real-time operating condition is a stable operating condition and the real-time load terminal voltage is less than or equal to the critical voltage value, it is predicted that the electronic load will be in a transient regulation condition at the next moment from the current moment, thereby determining that the sub-load model corresponding to the electronic load at the next moment from the current moment is the sub-load model corresponding to the transient regulation condition in the total load model; when the real-time operating condition is a transient regulation condition, the real-time load terminal voltage is less than or equal to the preset protection voltage threshold, and the real-time duration is greater than or equal to the preset protection delay, it is predicted that the electronic load will be in a transient regulation condition at the next moment from the current moment. At the next moment, if the load is in protection mode, then at the next moment, the sub-load model corresponding to the electronic load is determined to be the sub-load model corresponding to protection mode in the total load model. If the real-time operating condition is transient regulation mode or protection mode, and the real-time load terminal voltage is greater than or equal to the sum of the critical voltage value and the regression difference, then the electronic load is predicted to be in stable operation mode at the next moment, thus determining that at the next moment, the sub-load model corresponding to the electronic load is the sub-load model corresponding to stable operation mode in the total load model. If none of the above three conditions are met, then the electronic load is predicted to be in real-time mode at the next moment, thus determining that at the next moment, the sub-load model corresponding to the electronic load is the sub-load model corresponding to real-time mode in the total load model.

[0061] For example, the method described by the system of equations is as follows: based on the real-time load terminal voltage, the real-time duration, the real-time operating condition, the preset protection delay, the preset protection voltage threshold, and the critical voltage value, the sub-load model corresponding to the power electronic load at the next time moment is determined from the total load model. , in, For real-time operating conditions, This indicates that the real-time operating condition is a stable operating condition. This indicates that the real-time operating condition is a transient adjustment condition. M(1) represents the sub-load model corresponding to the stable operation condition; M(2) represents the sub-load model corresponding to the transient regulation condition; M(3) represents the sub-load model corresponding to the transient regulation condition. This is the critical voltage value; This refers to the real-time load terminal voltage. The preset protection voltage threshold; This refers to the real-time load terminal voltage. For real-time duration; Preset protection delay; The sum of the critical voltage value and the regression difference. This represents the sub-load model for the next time step from the current time step. The set recovery difference is used to filter out frequent model jumps caused by high-frequency noise, and at the same time ensures stability when the state switches from transient regulation or protection mode back to stable operation mode, preventing numerical oscillations.

[0062] Therefore, based on real-time load terminal voltage, duration, and current operating conditions, combined with preset protection delay, preset protection voltage threshold, and critical voltage value, the sub-load model for the next moment is dynamically predicted, achieving forward-looking, adaptive discrimination, and accurate modeling of the operating state of power electronic loads. This mechanism not only strictly adheres to the voltage-time dual criteria, effectively distinguishing the transition boundaries between stable operation, transient regulation, and protection conditions, but also introduces regression difference to avoid frequent oscillations of load operating conditions near the critical point, which would lead to frequent switching of sub-load models, significantly improving the robustness and engineering practicality of the sub-load model. Furthermore, by presetting the sub-load model for the next moment, the corresponding sub-load model can be activated in advance, allowing the converter to prepare for control in advance and shortening the transition time of operating condition switching. Furthermore, the converters of the power electronic loads inherently possess predictive or feedforward mechanisms. By pre-setting the sub-load model for the next moment, they also ensure seamless connection and high consistency between the external characteristics of the sub-load model and the actual control behavior of the power electronic load, thereby providing a high-fidelity, time-varying dynamic load model for power system stability analysis.

[0063] In summary, this solution obtains dual-loop control strategies for multiple power electronic loads to be modeled, wherein the dual-loop control strategies are used to describe the dual-loop control structure of the converter; for each dual-loop control strategy, the dual-loop control structure of the converter is determined based on the dual-loop control strategy, and the critical voltage value is determined based on the dual-loop control structure; for each power electronic load, the preset protection delay and preset protection voltage threshold of the converter built into it are obtained; based on the preset protection delay, the preset protection voltage threshold, and the critical voltage value, the load operating conditions of the power electronic load are divided, including stable operation condition, transient regulation condition, and protection condition; based on the load operating conditions and common physical structures, a total load model of the power electronic load is constructed, wherein the common physical structures are the physical devices shared by the converters built into the multiple power electronic loads to be modeled, and the total load model includes sub-load models corresponding one-to-one with each operating condition. This scheme identifies the dual-loop control structure of electronically powered loads and scientifically determines the critical voltage value accordingly. Simultaneously, it combines the inherent preset protection delay and protection voltage threshold of the converter to construct a three-state operating condition classification mechanism (stable operation condition, transient regulation condition, and protection condition) based on voltage-time dual criteria. On this basis, it integrates the common physical structures of the converter (such as capacitors, filter inductors, power switches, etc.) with the dynamic characteristics of operating condition adaptation, establishing a load model with universality and operating condition adaptability. This load model can represent the true external performance of electronically powered loads under different operating conditions, effectively overcoming the distortion defects of traditional comprehensive load models under transient or protection conditions. It significantly improves the accuracy of the load model's external performance under different disturbance scenarios, thereby enhancing the accuracy and reliability of power system stability analysis based on this load model.

[0064] Example 2: Another embodiment of this application relates to a power electronic load modeling device considering a converter. The implementation details of this embodiment's power electronic load modeling device are described below. The following details are provided for ease of understanding and are not essential for implementing this solution. A schematic diagram of the power electronic load modeling device 20 considering a converter in this embodiment can be seen as follows: Figure 2 As shown, it includes an acquisition unit 200, a determination unit 210, a division unit 220, and a construction unit 230.

[0065] The acquisition unit 200 is used to acquire the dual-loop control strategies of multiple power electronic loads to be modeled, wherein the dual-loop control strategies are used to describe the dual-loop control structure of the converter.

[0066] The determining unit 210 is used to determine the dual-loop control structure of the converter based on the dual-loop control strategy for each of the dual-loop control strategies, and to determine the critical voltage value based on the dual-loop control structure.

[0067] The acquisition unit 200 is also used to acquire the preset protection delay and preset protection voltage threshold of the built-in converter for each power electronic load.

[0068] The division unit 220 is used to divide the load operation conditions of the power electronic load based on the preset protection delay, the preset protection voltage threshold and the critical voltage value. The load operation conditions include stable operation conditions, transient adjustment conditions and protection conditions.

[0069] The construction unit 230 is used to construct the total load model of the power electronic load based on the load operating conditions and the common physical structure, wherein the common physical structure refers to the physical devices shared by the converters built into the multiple power electronic loads to be modeled, and the total load model includes sub-load models that correspond one-to-one with each operating condition.

[0070] In some examples, when the device is used to determine the critical voltage value based on the dual-loop control structure, it is specifically used to: obtain the engineering experience parameters corresponding to the dual-loop control structure, the engineering experience parameters being used to represent the dynamic response boundary and stability margin of the power electronic load under stable operating conditions; and calculate the critical voltage value based on the engineering experience parameters and in combination with the rated electrical quantity of the power electronic load.

[0071] In some examples, when the device is used to classify the load operating conditions of the power electronic load based on the preset protection delay, the preset protection voltage threshold, and the critical voltage value, and the load operating conditions include stable operating conditions, transient regulation conditions, and protection conditions, specifically: when the load terminal voltage is greater than the critical voltage value, the power electronic load is in the stable operating condition, which indicates that the power electronic load is in a steady-state safe operating state under rated load; when the load terminal voltage is less than or equal to the critical voltage value and greater than the preset protection voltage threshold, or when the load terminal voltage is less than or equal to the preset protection voltage threshold... When the load terminal voltage is less than the preset protection voltage threshold and the duration of the voltage being less than the preset protection delay is less than the preset protection delay, the power electronic load is in the transient regulation condition, which indicates that the power electronic load is in a state of dynamic response and regulation to external disturbances. When the load terminal voltage is less than or equal to the preset protection voltage threshold and the duration of the voltage being less than or equal to the preset protection voltage threshold is greater than or equal to the preset protection delay, the power electronic load is in the protection condition, which indicates that the power electronic load is in a protection state where it has no ability to regulate external disturbances.

[0072] In some examples, when the device is used to construct the total load model of the power electronic load based on the load operating conditions and the common physical structure, it is specifically used to: determine the common physical structure based on the converters built into the plurality of power electronic loads; obtain the electrical quantity reference command equation set corresponding to the common physical structure; for each operating condition in the load operating conditions, obtain the load characteristic equation set corresponding to the operating condition in combination with the dual-loop control structure of the power electronic load, wherein the operating condition is any one of the stable operating condition, transient regulation condition, and protection condition; and construct the total load model by combining the load characteristic equation set and the electrical quantity reference command equation set.

[0073] In some examples, when the device is used to obtain the load characteristic equation set corresponding to the operating condition in conjunction with the dual-loop control structure of the power electronic load, it is specifically used to: if the operating condition is a transient regulation operating condition, then in conjunction with the dual-loop control structure of the power electronic load and based on the device type of the converter, obtain the load characteristic equation set corresponding to the transient regulation operating condition, wherein the device type includes inverter, rectifier, DC-DC converter and AC-AC converter.

[0074] In some examples, the device is also used to: monitor the real-time load terminal voltage of each power electronic load to be modeled in real time; count the real-time duration of the load terminal voltage that is consistently lower than the preset protection voltage threshold; and determine the sub-load model corresponding to the power electronic load at the current moment from the total load model based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value.

[0075] In some examples, the device is also used to: determine the real-time operating condition of the power electronic load based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value, wherein the real-time operating condition is any one of stable operation, transient regulation, and protection; and determine the sub-load model corresponding to the power electronic load at the next time moment from the total load model based on the real-time load terminal voltage, the real-time duration, the real-time operating condition, the preset protection delay, the preset protection voltage threshold, and the critical voltage value.

[0076] It is worth mentioning that all modules involved in this embodiment are logical modules. In practical applications, a logical unit can be a physical unit, a part of a physical unit, or a combination of multiple physical units. Furthermore, to highlight the innovative aspects of this application, this embodiment does not introduce units that are not closely related to solving the technical problems proposed in this application; however, this does not mean that other units are absent in this embodiment.

[0077] Example 3: This disclosure also provides an electronic device, comprising: a memory for storing at least one instruction; and a processor for calling the instruction stored in the memory to execute the power electronic load modeling method considering the converter in any of the above embodiments.

[0078] Example 4: This disclosure also provides a computer-readable storage medium storing at least one executable instruction, which is loaded and executed by a processor to implement the power electronic load modeling method considering converters in any of the above embodiments.

[0079] Example 5: This disclosure also provides a computer program product, which includes computer program code that, when executed by a computer, causes the computer to perform the power electronic load modeling method considering the converter in any of the above embodiments.

[0080] Those skilled in the art will understand that embodiments of this disclosure can be provided as methods, systems, or computer program products. Therefore, this disclosure can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this disclosure can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0081] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0082] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0083] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0084] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0085] Memory may include non-persistent memory 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.

[0086] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that 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, magnetic magnetic disk storage 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.

[0087] It should be noted that the terms "first," "second," and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. Terms such as "including" or "contains" mean that the element preceding the word covers the element listed after the word, and do not exclude the possibility of covering other elements as well.

[0088] Although operations are described in a specific order in the accompanying drawings in this disclosure, it should not be construed as requiring these operations to be performed in the specific order or serial order shown, or requiring all of the shown operations to obtain the desired result. In certain environments, multitasking and parallel processing may be advantageous.

[0089] Finally, it should be noted that the above content is only used to illustrate the technical solution of this disclosure, and is not intended to limit the scope of protection of this disclosure. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of this disclosure do not depart from the substance and scope of the technical solution of this disclosure.

Claims

1. A method of modeling power electronicized loads taking into account a power converter, characterized in that, include: Obtain dual-loop control strategies for multiple power electronic loads to be modeled, wherein the dual-loop control strategies are used to describe the dual-loop control structure of the converter; For each of the aforementioned dual-loop control strategies, the dual-loop control structure of the converter is determined based on the dual-loop control strategy, and the critical voltage value is determined based on the dual-loop control structure; For each power electronic load, obtain the preset protection delay and preset protection voltage threshold of the built-in converter; The load operation conditions of the power electronic load are divided based on the preset protection delay, the preset protection voltage threshold, and the critical voltage value. The load operation conditions include stable operation conditions, transient regulation conditions, and protection conditions. Based on the load operating conditions and the common physical structure, a total load model of the power electronic load is constructed. The common physical structure refers to the physical devices shared by the converters built into the multiple power electronic loads to be modeled. The total load model includes sub-load models that correspond one-to-one with each operating condition.

2. The power electronic load modeling method considering converters according to claim 1, characterized in that, The determination of the critical voltage value based on the dual-loop control structure includes: Obtain the engineering experience parameters corresponding to the dual-loop control structure. The engineering experience parameters are used to represent the dynamic response boundary and stability margin of the power electronic load under stable operating conditions. Based on the engineering experience parameters and in combination with the rated electrical quantities of the power electronic load, the critical voltage value is calculated.

3. The power electronic load modeling method considering converters according to claim 1, characterized in that, The load operation conditions of the power electronic load are divided based on the preset protection delay, the preset protection voltage threshold, and the critical voltage value. These load operation conditions include stable operation conditions, transient regulation conditions, and protection conditions. When the load terminal voltage is greater than the critical voltage value, the power electronic load is in the stable operating condition, which means that the power electronic load is in a steady-state safe operating state under the rated load. When the load terminal voltage is less than or equal to the critical voltage value and greater than the preset protection voltage threshold, or when the load terminal voltage is less than or equal to the preset protection voltage threshold and the duration of the load terminal voltage being less than the preset protection voltage threshold is less than the preset protection delay, the power electronic load is in the transient regulation condition. The transient regulation condition indicates that the power electronic load is in a state of dynamic response and regulation to external disturbances. When the load terminal voltage is less than or equal to the preset protection voltage threshold, and the duration of the load terminal voltage being less than or equal to the preset protection voltage threshold is greater than or equal to the preset protection delay, the power electronic load is in the protection condition. The protection condition indicates that the power electronic load is in a protection state where it has no ability to regulate external disturbances.

4. The power electronic load modeling method considering converters according to claim 1, characterized in that, The total load model for the electronic load, constructed based on the load operating conditions and shared physical structure, includes: Based on the converters built into the multiple power electronic loads, a common physical structure is determined; Obtain the electrical quantity reference instruction equation set corresponding to the common physical structure; For each operating condition in the load operation, the load characteristic equation set corresponding to the operating condition is obtained by combining the dual-loop control structure of the power electronic load. The operating condition is any one of the stable operation condition, transient adjustment condition, and protection condition. The total load model is constructed by combining the load characteristic equation set and the electrical quantity reference command equation set.

5. The power electronic load modeling method considering converters according to claim 4, characterized in that, The load characteristic equations corresponding to the operating condition are obtained by combining the dual-loop control structure of the power electronic load, including: If the operating condition is a transient regulation condition, then, in combination with the dual-loop control structure of the power electronic load and based on the device type of the converter, a set of load characteristic equations corresponding to the transient regulation condition is obtained, wherein the device type includes inverter, rectifier, DC-DC converter and AC-AC converter.

6. The power electronic load modeling method considering converters according to claim 4, characterized in that, The method further includes: For each power electronic load to be modeled, the real-time load terminal voltage of the power electronic load is monitored in real time; The real-time duration of the load terminal that is consistently below the preset protection voltage threshold is recorded. Based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value, the sub-load model corresponding to the power electronic load at the current moment is determined from the total load model.

7. The power electronic load modeling method considering converters according to claim 6, characterized in that, The method further includes: Based on the real-time load terminal voltage, the real-time duration, the preset protection delay, the preset protection voltage threshold, and the critical voltage value, the real-time operating condition of the power electronic load is determined, wherein the real-time operating condition is any one of the following: stable operation condition, transient adjustment condition, and protection condition. Based on the real-time load terminal voltage, the real-time duration, the real-time operating conditions, the preset protection delay, the preset protection voltage threshold, and the critical voltage value, the sub-load model corresponding to the power electronic load at the next moment is determined from the total load model.

8. A power electronic load modeling device considering converters, characterized in that, include: An acquisition unit is used to acquire the dual-loop control strategies of multiple power electronic loads to be modeled, wherein the dual-loop control strategies are used to describe the dual-loop control structure of the converter. The determining unit is used to determine the dual-loop control structure of the converter based on the dual-loop control strategy for each of the dual-loop control strategies, and to determine the critical voltage value based on the dual-loop control structure. The acquisition unit is also used to acquire the preset protection delay and preset protection voltage threshold of the built-in converter for each power electronic load. The division unit is used to divide the load operation conditions of the power electronic load based on the preset protection delay, the preset protection voltage threshold and the critical voltage value. The load operation conditions include stable operation conditions, transient adjustment conditions and protection conditions. The construction unit is used to construct the total load model of the power electronic load based on the load operating conditions and the common physical structure, wherein the common physical structure refers to the physical devices shared by the converters built into the multiple power electronic loads to be modeled, and the total load model includes sub-load models corresponding one-to-one with each operating condition.

9. An electronic device, characterized in that, include: Memory, used to store at least one instruction; as well as A processor is configured to invoke instructions stored in the memory to execute the power electronic load modeling method for converters as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one executable instruction, which is loaded and executed by a processor to implement the power electronic load modeling method for converters as described in any one of claims 1-7.

Images