Methods and systems for characterizing network energy amplitude and phase dynamics in three-phase AC systems

Abstract

This invention proposes a method and system for dynamically characterizing the amplitude and phase of network energy in a three-phase AC system, belonging to the field of power system analysis and control. The method includes: constructing a network energy vector by treating the energy storage of three-phase inductors or capacitors as a whole; defining the amplitude of the network energy vector to characterize the total stored energy of the three phases; defining the phase of the network energy vector to characterize the dynamic alternating characteristics within the three-phase energy; establishing a dynamic relationship between instantaneous power and the dynamic changes of the network energy vector, and standardizing it; wherein instantaneous active power affects the amplitude change of the network energy vector, and instantaneous reactive power affects the phase change of the network energy vector. This invention can intuitively reveal the physical essence of electromagnetic scale dynamics in novel power systems, providing theoretical support for system stability analysis and control.

Description

Technical Field

[0001] This invention belongs to the field of power system analysis and control technology, and particularly relates to a method and system for dynamic characterization of network energy amplitude and phase of a three-phase AC system. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Inductors and capacitors are the core components of power networks and the physical basis of the electromagnetic dynamics of power systems. The electromagnetic dynamics of a power system can essentially be viewed as the migration and changes in the states of inductors and capacitors in the network under the excitation of the power source.

[0004] In the circuit theory system, a complete characterization method has been established based on inductor current and capacitor voltage for the electromagnetic scale dynamic response mechanism of power networks with inductors and capacitors as the core.

[0005] However, due to the different characteristics of inductors and capacitors in circuit theory (the former stores magnetic field energy through current, while the latter stores electric field energy through voltage), the description of the dynamic response mechanism of the network needs to be developed separately for each component type, making the overall description quite complex. In traditional power systems, synchronous machines serve as the main excitation source, exhibiting voltage source characteristics on an electromagnetic scale. Based on the aforementioned circuit theory mechanism, a certain degree of intuitive physical description can still be provided for the electromagnetic scale transition evolution process of the power network from one quasi-steady state to another under this type of excitation.

[0006] However, with the development of new power systems, the proportion of new energy sources using power electronics has increased significantly. These new energy sources achieve rapid instantaneous power control through converters, and their output voltage and current characteristics are more complex than those of traditional synchronous machines. Against this backdrop, traditional network dynamic response mechanisms based on circuit theory exhibit significant complexity when analyzing electromagnetic scale transition evolution processes. They not only need to handle the coupling relationships of multiple types of components and multiple frequency components, but also struggle to provide intuitive explanations for the physical nature of related dynamic problems, such as the transients of new energy grid connection and voltage and current oscillations caused by power fluctuations. Therefore, they cannot meet the needs of electromagnetic scale dynamic analysis in new power systems.

[0007] Furthermore, although inductors and capacitors differ at the circuit parameter level, both are energy storage elements in power networks. The energy they store is a higher-dimensional and more fundamental unified description of circuit parameters such as current and voltage. Therefore, re-examining the multidimensional energy states of inductors and capacitors in a three-phase AC power network environment from an energy perspective, and exploring the interaction between instantaneous active power, instantaneous reactive power, and this network energy, is of fundamental and crucial significance for intuitively understanding the dynamic evolution of the network electromagnetic scale under the excitation of numerous new energy sources based on rapid instantaneous power control, and for revealing the physical mechanism of electromagnetic scale dynamic problems in new power systems. Summary of the Invention

[0008] To overcome the shortcomings of the prior art, this invention provides a method and system for characterizing the network energy amplitude and phase dynamics of a three-phase AC system. This method can uniformly describe the energy storage state of inductors and capacitors and establish a direct relationship between instantaneous power and network energy dynamics, providing an intuitive and unified physical basis for the electromagnetic scale dynamic analysis of new power systems.

[0009] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions: The first aspect of this invention provides a method for dynamically characterizing the network energy amplitude and phase of a three-phase AC system; A method for dynamically characterizing the network energy amplitude and phase of a three-phase AC system includes: The energy storage of three-phase inductors or three-phase capacitors is treated as a whole to construct a network energy vector; The magnitude of the network energy vector is defined to characterize the total energy of the three-phase storage. Define the phase of the network energy vector to characterize the dynamic alternation characteristics within the three-phase energy; A dynamic relationship is established between instantaneous power and the dynamic change of the network energy vector, and then normalized; wherein instantaneous active power affects the amplitude change of the network energy vector, and instantaneous reactive power affects the phase change of the network energy vector.

[0010] As a further technical solution, the network energy vector is:

[0011] The network energy vector transformation matrix C E equal:

[0012] In the formula, For network energy vectors; and These are the projection components of the network energy vector onto the two coordinate axes of the two-phase stationary coordinate system, respectively; , , Inductors or capacitors respectively The energy stored in each of the three phases; , , These are the three-phase currents flowing through the inductor or the three-phase voltages across the capacitor, respectively. Depending on whether it is an inductor or a capacitor, it represents the inductance value or the capacitance value, respectively.

[0013] As a further technical solution, the magnitude of the network energy vector characterizes the total energy of the three phases, and its relationship with the magnitude of the space vector of inductor current or capacitor voltage is as follows:

[0014] In the formula, The magnitude of the network energy vector. This represents the magnitude of the corresponding inductor current or capacitor voltage vector.

[0015] As a further technical solution, the phase of the network energy vector characterizes the alternating dynamics within the three-phase energy, and its relationship with the phase of the space vector of inductor current or capacitor voltage is as follows:

[0016] In the formula, The angle of the network energy vector in the two-phase stationary coordinate system. The angle of the inductor current or capacitor voltage vector in a two-phase stationary coordinate system; As a further technical solution, establishing the dynamic relationship between instantaneous power and the dynamic change of the network energy vector includes constructing the dynamic equations of energy-instantaneous power for a three-phase inductive network and energy-instantaneous power for a three-phase capacitor network.

[0017] As a further technical solution, the energy-instantaneous power dynamic equation of the per-unit three-phase inductor network is as follows:

[0018] In the formula, L * Indicates the per-unit value of inductance. This represents the per-unit value of the inductor current vector magnitude. This represents the energy amplitude of the three-phase inductor network after standardization. This represents the instantaneous active power injected into the three-phase inductor after standardization. The time is the standardized time. This refers to the energy phase of a three-phase inductor network. The rated angular velocity for rotation at a power frequency of 50Hz; The angular velocity of the rotating coordinate system at twice the power frequency after standardization; This refers to the normalized inductive instantaneous reactive power injected into the three-phase inductor.

[0019] As a further technical solution, the energy-instantaneous power dynamic equation of the per-unit three-phase capacitor network is:

[0020] In the formula, C * This indicates the per-unit value of the capacitor. This represents the per-unit value of the capacitor voltage vector magnitude. This represents the energy amplitude of the three-phase capacitor network after standardization. This represents the instantaneous active power injected into the three-phase capacitor after standardization. This refers to the energy phase of a three-phase capacitor network. This represents the capacitive instantaneous reactive power of the injected three-phase capacitor after standardization.

[0021] The second aspect of the present invention provides a network energy amplitude and phase dynamic characterization system for a three-phase AC system.

[0022] A network energy amplitude and phase dynamic characterization system for a three-phase AC system includes: The energy vector construction module is configured to construct a network energy vector by treating the energy storage of a three-phase inductor or a three-phase capacitor as a whole. The amplitude calculation module is configured to: define the amplitude of the network energy vector to characterize the total energy of the three-phase storage; The phase calculation module is configured to: define the phase of the network energy vector to characterize the dynamic alternation characteristics within the three-phase energy; The dynamic relationship modeling module is configured to: establish the dynamic relationship between instantaneous power and the dynamic change of the network energy vector, and perform per-unit scaling; wherein instantaneous active power affects the amplitude change of the network energy vector, and instantaneous reactive power affects the phase change of the network energy vector.

[0023] A third aspect of the present invention provides a computer-readable storage medium having a program stored thereon, which, when executed by a processor, implements the steps in the method for dynamic characterization of network energy amplitude and phase of a three-phase AC system as described in the first aspect of the present invention.

[0024] The fourth aspect of the present invention provides an electronic device, including a memory, a processor, and a program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps in the method for dynamic characterization of network energy amplitude and phase of a three-phase AC system as described in the first aspect of the present invention.

[0025] The above one or more technical solutions have the following beneficial effects: This invention defines a network energy vector, treating the energy of three-phase inductors or capacitors as a whole. By utilizing the vector magnitude and phase angle, it achieves a unified characterization of the energy state of both inductors and capacitors. There is no need to distinguish between component types; their electromagnetic scale dynamic characteristics can be fully described using only the same vector model. Furthermore, by adjusting the network energy vector transformation matrix... bc The sequence of two-phase energy adapts to the differences between energy phase sequence and current and voltage phase sequence, further simplifying the derivation process of the correlation between energy and electrical parameters, and significantly reducing the complexity of electromagnetic scale dynamic analysis of three-phase AC systems.

[0026] This invention establishes an instantaneous power drive mechanism, clarifying the quantitative impact of instantaneous active and reactive power on the network energy state. For example, instantaneous active power directly determines the rate of increase or decrease of the total energy of inductors or capacitors, while instantaneous reactive power directly determines the rotation speed of the energy vector. By adjusting the instantaneous active power of the renewable energy converter, the network energy amplitude can be precisely controlled to stabilize current and voltage amplitudes; by adjusting the instantaneous reactive power, the energy phase angle rotation speed can be precisely controlled to maintain system synchronization. Simultaneously, based on the dynamic model of the network energy vector, the impact of control measures on the system's electromagnetic dynamics can be quickly quantified and analyzed, providing a solid theoretical foundation for the stability assurance of new power systems and facilitating the safe and efficient grid connection of high-proportion renewable energy sources.

[0027] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0028] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0029] Figure 1 This is a flowchart of the method in the first embodiment.

[0030] Figure 2 This is a system structure diagram of the second embodiment. Detailed Implementation

[0031] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0032] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0033] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0034] The overall idea of ​​this invention is as follows: This invention provides a method and system for dynamic characterization of network energy amplitude and phase in a three-phase AC system. By defining a network energy vector, it achieves a unified characterization of inductor and capacitor energy, and establishes a dynamic mechanism for instantaneous power-driven changes in network energy state, thus solving the problems of complex descriptions and unintuitive physical essence in traditional methods.

[0035] Example 1 This embodiment discloses a method for dynamic characterization of network energy amplitude and phase of a three-phase AC system; like Figure 1 As shown, a method for dynamically characterizing the network energy amplitude and phase of a three-phase AC system includes: Step S1: Treat the energy storage of three-phase inductors or three-phase capacitors as a whole to construct a network energy vector; Step S2: Define the magnitude of the network energy vector to characterize the total energy of the three-phase storage. Step S3: Define the phase of the network energy vector to characterize the dynamic alternation characteristics within the three-phase energy. Step S4: Establish the dynamic relationship between instantaneous power and the dynamic change of the network energy vector, and standardize it; wherein instantaneous active power affects the amplitude change of the network energy vector, and instantaneous reactive power affects the phase change of the network energy vector.

[0036] Specifically, it also includes the following: Step S1: Treat the energy storage of three-phase inductors or three-phase capacitors as a whole to construct a network energy vector.

[0037] In a single-phase AC system, the energy stored in a single inductor and capacitor is related to its own current and voltage, respectively, as shown in equation (1): (1) in, The energy stored in a single inductor element; The energy stored in a single capacitor element; L and C are the inductance or capacitance values ​​of the single element, respectively. and These are the instantaneous values ​​of the inductor current or capacitor voltage on a single inductor or capacitor, respectively.

[0038] In a three-phase AC power system, inductors and capacitors generally exist in a three-phase form. That is, at a certain location, there are inductors and capacitors of the same size in all three phases (a, b, and c). At the same time, the energy stored in the three-phase inductors and capacitors in an AC power system is always in a dynamic state of flux.

[0039] When a three-phase AC power system is in a dynamic transition process on an electromagnetic scale, without considering the zero-sequence component, the current flowing through the three-phase inductors or the voltage across the three-phase capacitors can be expressed as equation (2). (2) in, and Depending on the inductance and capacitance, the instantaneous value of the current and the amplitude of the sinusoidal current, or the instantaneous value of the voltage and the amplitude of the sinusoidal voltage, are respectively represented. Depending on the type of inductance and capacitance, these represent inductance or capacitance values, respectively. , These are the rotational angular velocity and initial phase angle of the instantaneous inductor current or capacitor voltage in phase a, respectively. Represents the fundamental frequency component, and ,and Other values ​​do not represent the harmonic order, but rather the corresponding angular velocity. Sum of values It can be any value.

[0040] At this time, the energy stored in each of the three-phase inductors or capacitors is as shown in equation (3). (3) Where E and K represent the energy stored in an inductive element and its inductance value, or the energy stored in a capacitive element and its capacitance value, depending on the inductance and capacitance.

[0041] From the double-angle formula and the product-to-sum formula, we can further derive the energy expressions for each phase as shown in equation (4):

[0042]

[0043] (4) As can be seen from equation (4), the energy stored in each phase of a three-phase inductor or capacitor can be divided into two parts. The first part is completely consistent in the three phases abc, always changing in the same phase, which determines the overall energy level of the three-phase element; the second part has the same amplitude among the three phases abc, but the phases differ by 120°, which does not affect the total energy of the three phases, reflecting the dynamic characteristic of the energy of each phase constantly changing internally.

[0044] The energy of three-phase inductors or capacitors is considered as a whole, which is called network energy. To gain a more intuitive understanding of network energy under three-phase AC, a network energy vector is defined. The concept of is expressed as shown in equation (5): (5) The network energy vector transformation matrix As shown in the formula, (6) In the formula, For network energy vectors; and These are the projection components of the network energy vector onto the two coordinate axes of the two-phase stationary coordinate system, respectively; , , Inductors or capacitors respectively The energy stored in each of the three phases; , , These are the three-phase currents flowing through the inductor or the three-phase voltages across the capacitor, respectively. Depending on the type of inductance and capacitance, these represent inductance or capacitance values, respectively. bc The sequence of two-phase energy is commonly used in power systems. abc The phase sequence is different because it takes into account the difference between the energy phase sequence and the current or voltage phase sequence mentioned above. In order to more easily establish the connection between the two, the phase sequence is adjusted when establishing the energy vector.

[0045] Step S2: Define the amplitude of the network energy vector to characterize the total amount of three-phase stored energy. The amplitude of the network energy vector is the sum of the three-phase stored energy, used to characterize the total amount of three-phase stored energy, and corresponds to 3 / 4K times the square of the amplitude of the current and voltage space vectors.

[0046] The magnitude of the defined network energy vector is equal to the total energy of the three-phase inductor or capacitor, which is the sum of the first part of the energy of each phase in the three phases, and the magnitude of the energy vector is equal to 3 / 4K times the square of the magnitude of the corresponding current (for inductors) or voltage (for capacitors).

[0047] In defining the magnitude of the network energy vector, since the zero-sequence component in the three-phase current or voltage is not considered, equation (7) holds.

[0048] (7) The magnitude of the network energy vector is shown in equation (8): (8) In the formula, This represents the magnitude of the network energy vector.

[0049] Since expression (7) holds, the following relationship holds: (9) Therefore, the relationship shown in equation (10) can be derived. (10) Substituting equation (10) into equation (8), we obtain equation (11). (11) Equation (11) shows that, in the three-phase electromagnetic scale dynamic transition process without considering the zero-sequence component, the defined network energy vector amplitude is equal to the sum of the energy of the three-phase inductors or capacitors, which characterizes the numerical value of the stored energy.

[0050] Furthermore, the relationship between the magnitude of the network energy vector and the space vector of the three-phase inductor current or capacitor voltage can be derived. The three-phase inductor current or capacitor voltage and its vector projection in the two-phase stationary coordinate system follow the relationship shown in equation (12).

[0051] (12) Substituting equation (12) into equation (11), we can obtain equation (13).

[0052] (13) in, and These are the vector projections of inductor current or capacitor voltage in a two-phase stationary coordinate system, respectively. This represents the magnitude of the corresponding current or voltage vector.

[0053] Equation (13) shows that, during the electromagnetic scale dynamic process, the network energy vector amplitude is That is, the sum of the energy of the three-phase inductors or capacitors, which is numerically equal to the square of the corresponding current or voltage vector amplitude multiplied by 3 / 4 of the inductor or capacitor value.

[0054] Step S3 defines the phase of the network energy vector to characterize the dynamic alternation characteristics within the three-phase energy, corresponding to twice the phase of the current or voltage space vector.

[0055] The phase of the network energy vector is determined by the second part of the energy in each phase. Since this part has equal amplitude and a phase difference of 120° in all three phases, its scalar sum is always zero, so it does not affect the total energy of the three phases, but only reflects the dynamic alternation relationship within the energy. The angle of the rotation vector obtained by superimposing the second part of the energy in each phase on axes acb that are 120° apart in space is equal to the phase of the energy vector, which characterizes the dynamic alternation characteristics within the three-phase energy. Numerically, this angle is also equal to twice the phase of the corresponding inductor current or capacitor voltage space vector.

[0056] Based on the definition of network energy vector, and taking into account the relationship between the three phase energies, the dynamic changes of internal energy are described by the angle of the network energy vector. Thus, according to equation (5), the angle of the network energy vector can be derived as shown in equation (14).

[0057] (14) in, The angle of the network energy vector in the two-phase stationary coordinate system.

[0058] For the vector of inductor current or capacitor voltage, its angle Then it can be expressed by equation (15).

[0059] (15) in, It is the angle of the inductor current or capacitor voltage vector in a two-phase stationary coordinate system.

[0060] According to equation (7), the relationship shown in equation (16) holds. (16) Furthermore, from equations (14) and (15), we can obtain that... (17) Equation (17) shows that in electromagnetic scale dynamics, the phase angle of the network energy vector is equal to twice the phase angle of its corresponding inductor current or capacitor voltage space vector.

[0061] Therefore, considering the three-phase energy of a three-phase inductor or capacitor in a three-phase AC power network as a whole, namely the network element energy, this energy is constantly changing. The total stored energy and the dynamic relationship of the waxing and waning of the three phases within this energy are two indispensable states for describing this energy. It can be described using the network energy vector as a ball of energy in a state of rotation, the magnitude of which is equal to... It describes the total energy stored; its rotation angle is equal to twice the angle of the corresponding voltage and current space vectors, describing the dynamic alternation characteristics of the energy's internal three phases.

[0062] Step S4: Establish the dynamic relationship between instantaneous power and the dynamic change of the network energy vector, and standardize it; wherein instantaneous active power affects the amplitude change of the network energy vector, and instantaneous reactive power affects the phase change of the network energy vector.

[0063] By treating the energy of a three-phase inductor or capacitor in a three-phase AC power network as a whole, it is defined as network energy and represented by a network energy vector. This energy can be figuratively described as a ball of energy in a state of rotation, the amplitude of which reflects the amount of energy stored in the element, and its numerical value is equal to... The rotation angle corresponds to twice the phase angle of the voltage or current space vector.

[0064] Based on the aforementioned two-dimensional representation method of network energy vector, this study further reveals the dynamic relationship between instantaneous power components and network energy in a three-phase AC system, laying a theoretical foundation for subsequent analysis of electromagnetic scale dynamics in novel power systems.

[0065] The magnitude of the energy vector in a three-phase inductive network is proportional to the square of the magnitude of the current space vector. (18) in, This represents the energy vector amplitude of the three-phase inductor network. This corresponds to the magnitude of the inductor current vector.

[0066] The derivative of the energy vector magnitude of the three-phase inductor network is shown in equation (19). (19) in, and These are the vector projections of the inductor current in the two-phase stationary coordinate system.

[0067] Its value is equal to the instantaneous active power injected into the three-phase inductor. The expression: (20) in, The inductor voltage in a two-phase stationary coordinate system α Projection on the axis; The inductor voltage in a two-phase stationary coordinate system β Projection on the axis.

[0068] Equation (20) shows that the instantaneous active power on the three-phase inductor can replenish the energy of the inductor, which will affect the magnitude of its energy vector.

[0069] The relationship between instantaneous reactive power and the energy vector of the three-phase inductor network is shown in equation (21).

[0070] (twenty one) in, The angular velocity of the rotating coordinate system at a power frequency of 50Hz; The angular velocity of the rotating coordinate system is twice the power frequency. The phase angle is the inductor current vector. The phase angle is the inductor energy vector.

[0071] Equation (21) shows that the instantaneous reactive power on the three-phase inductor affects the rotation speed of its network energy vector. A certain amount of reactive power is required to maintain the network energy vector at its rated angular velocity for a certain three-phase inductor network amplitude.

[0072] Similarly, a similar relationship can be obtained for three-phase capacitors. (twenty two) in, The instantaneous active power injected into the three-phase capacitor, This represents the energy vector magnitude of the three-phase capacitor network. This corresponds to the magnitude of the capacitor voltage vector. and These are the vector projections of the capacitor voltage in the two-phase stationary coordinate system.

[0073] (twenty three) in, This represents the capacitive instantaneous reactive power injected into the three-phase capacitor after standardization. The phase angle of the capacitor voltage vector; The phase angle is the energy vector of the capacitor.

[0074] The instantaneous active power on a three-phase capacitor can replenish the capacitor's energy, which will affect its energy vector amplitude, i.e., the magnitude of the total three-phase energy. The instantaneous capacitive reactive power on the three-phase capacitor affects the rotation speed of its network energy vector. For a given three-phase capacitor network energy vector amplitude, a certain amount of capacitive reactive power is required to maintain the rated angular velocity of rotation.

[0075] The above network energy vector expression and the dynamic equation of network energy state change driven by instantaneous power are normalized and denoted as follows: This represents the per-unit value. The base values ​​for each parameter in the system are selected as follows: Power base value angular velocity base value Time base value Energy base value Voltage vector amplitude base value The energy vector magnitude expression for a three-phase inductive-capacitive network is standardized to per-unit value. (twenty four) The expressions for the energy amplitude and phase per unit of the three-phase inductor and three-phase capacitor networks are obtained.

[0076] The dynamic equations for energy-instantaneous power in a three-phase inductive network are shown in equation (25). (25) In the formula, This represents the energy amplitude of the three-phase inductor network after standardization. This represents the instantaneous active power injected into the three-phase inductor after standardization. The time is the standardized time. This refers to the energy phase of a three-phase inductor network. The rated angular velocity for rotation at a power frequency of 50Hz; This is the angular velocity of the 2x power frequency rotating coordinate system after standardization.

[0077] The dynamic equation for the energy-instantaneous power of a three-phase capacitor network is shown in equation (26). (26) In the formula, This represents the energy amplitude of the three-phase capacitor network after standardization. This represents the instantaneous active power injected into the three-phase capacitor after standardization. This refers to the phase of a three-phase capacitor network.

[0078] Thus, the concept of network energy, used to describe the energy storage properties of three-phase inductors and capacitors in a three-phase AC power network, and the dynamic mechanism of instantaneous power driving changes in network energy state at the electromagnetic scale, have been fully established. Example 2 This embodiment discloses a network energy amplitude and phase dynamic characterization system for a three-phase AC system; like Figure 2 As shown, a network energy amplitude and phase dynamic characterization system for a three-phase AC system includes: The energy vector construction module is configured to construct a network energy vector by treating the energy storage of a three-phase inductor or a three-phase capacitor as a whole. The amplitude calculation module is configured to: define the amplitude of the network energy vector to characterize the total energy of the three-phase storage; The phase calculation module is configured to: define the phase of the network energy vector to characterize the dynamic alternation characteristics within the three-phase energy; The dynamic relationship modeling module is configured to: establish the dynamic relationship between instantaneous power and the dynamic change of the network energy vector, and perform per-unit scaling; wherein instantaneous active power affects the amplitude change of the network energy vector, and instantaneous reactive power affects the phase change of the network energy vector.

[0079] Example 3 The purpose of this embodiment is to provide a computer-readable storage medium.

[0080] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the method for dynamic characterization of network energy amplitude and phase of a three-phase AC system as described in Example 1.

[0081] Example 4 The purpose of this embodiment is to provide an electronic device.

[0082] An electronic device includes a memory, a processor, and a program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps in the method for dynamic characterization of network energy amplitude and phase of a three-phase AC system as described in Embodiment 1.

[0083] The steps and methods involved in the apparatuses of Embodiments 2, 3, and 4 above correspond to those in Embodiment 1. For specific implementation details, please refer to the relevant description section of Embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media including one or more instruction sets; it should also be understood as including any medium capable of storing, encoding, or carrying an instruction set for execution by a processor and enabling the processor to perform any of the methods in this invention.

[0084] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0085] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for dynamically characterizing the network energy amplitude and phase of a three-phase AC system, characterized in that, include: The energy storage of a three-phase inductor or a three-phase capacitor is treated as a whole to construct a network energy vector; the network energy vector is: In the formula, For network energy vectors; and These are the projection components of the network energy vector onto the two coordinate axes of the two-phase stationary coordinate system, respectively; , , Inductors or capacitors respectively The energy stored in each of the three phases; , , These are the three-phase currents flowing through the inductor or the three-phase voltages across the capacitor, respectively. Depending on the type of inductance and capacitance, these represent inductance or capacitance values, respectively. The magnitude of the network energy vector is defined to characterize the total amount of three-phase stored energy, and its relationship with the magnitude of the space vector of inductor current or capacitor voltage is as follows: In the formula, The magnitude of the network energy vector. This represents the magnitude of the space vector corresponding to the inductor current or capacitor voltage; The phase of the network energy vector is defined to characterize the dynamic alternation characteristics within the three-phase energy, and its relationship with the phase of the space vector of inductor current or capacitor voltage is as follows: In the formula, The angle of the network energy vector in the two-phase stationary coordinate system. The angle of the space vector of inductor current or capacitor voltage in a two-phase stationary coordinate system; A dynamic relationship is established between instantaneous power and the dynamic change of the network energy vector, and then normalized; wherein instantaneous active power affects the amplitude change of the network energy vector, and instantaneous reactive power affects the phase change of the network energy vector.

2. The method for dynamically characterizing the network energy amplitude and phase of a three-phase AC system as described in claim 1, characterized in that, Establishing the dynamic relationship between instantaneous power and the dynamic change of the network energy vector includes constructing the energy-instantaneous power dynamic equations for a three-phase inductive network and the energy-instantaneous power dynamic equations for a three-phase capacitor network.

3. The method for dynamically characterizing the network energy amplitude and phase of a three-phase AC system as described in claim 2, characterized in that, The normalized three-phase inductive network energy-instantaneous power dynamic equation is as follows: In the formula, Indicates the per-unit value of inductance. This represents the per-unit value of the inductor current vector magnitude. This represents the energy amplitude of the three-phase inductor network after standardization. This represents the instantaneous active power injected into the three-phase inductor after standardization. The time is the standardized time. This refers to the energy phase of a three-phase inductor network. The rated angular velocity for rotation at a power frequency of 50Hz; The angular velocity of the rotating coordinate system at twice the power frequency after standardization; This refers to the normalized inductive instantaneous reactive power injected into the three-phase inductor.

4. The method for dynamically characterizing the network energy amplitude and phase of a three-phase AC system as described in claim 2, characterized in that, The energy-instantaneous power dynamic equation of the three-phase capacitor network after per-unit scaling is: In the formula, This indicates the per-unit value of the capacitor. This represents the per-unit value of the capacitor voltage vector magnitude. This represents the energy amplitude of the three-phase capacitor network after standardization. This represents the instantaneous active power injected into the three-phase capacitor after standardization. This refers to the energy phase of a three-phase capacitor network. The time is the standardized time. The rated angular velocity for rotation at a power frequency of 50Hz; The angular velocity of the rotating coordinate system at twice the power frequency after standardization; This represents the capacitive instantaneous reactive power of the injected three-phase capacitor after standardization.

5. A network energy amplitude and phase dynamic characterization system for a three-phase AC system, employing the network energy amplitude and phase dynamic characterization method for a three-phase AC system as described in any one of claims 1-4, characterized in that, include: The energy vector construction module is configured to construct a network energy vector by treating the energy storage of a three-phase inductor or a three-phase capacitor as a whole. The amplitude calculation module is configured to: define the amplitude of the network energy vector to characterize the total energy of the three-phase storage; The phase calculation module is configured to: define the phase of the network energy vector to characterize the dynamic alternation characteristics within the three-phase energy; The dynamic relationship modeling module is configured to: establish the dynamic relationship between instantaneous power and the dynamic changes of the network energy vector, and perform per-unit scaling; The instantaneous active power affects the amplitude change of the network energy vector, and the instantaneous reactive power affects the phase change of the network energy vector.

6. A computer-readable storage medium having a program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps in the method for dynamic characterization of network energy amplitude and phase of a three-phase AC system as described in any one of claims 1-4.

7. An electronic device comprising a memory, a processor, and a program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps in the method for dynamic characterization of network energy amplitude and phase of a three-phase AC system as described in any one of claims 1-4.

Images