A method and apparatus for controlling a rectifier

Abstract

The embodiment of the present application provides a method and device for rectifier control. The method comprises the following steps: determining reactive power and active power according to the sampling voltage and the sampling current of a three-phase alternating current signal; determining given active power according to the given voltage and the sampling voltage of a direct current signal; determining a target voltage vector for model predictive control according to the active power, the reactive power, the given active power and a Hamilton dissipation model with injection damping; performing model predictive control according to the target voltage vector to obtain a control signal of the rectifier; and controlling the rectifier according to the control signal. The method can weaken the impedance of a power transmission line and enhance system stability, thereby effectively controlling the stable current output by the rectifier.

Description

Technical Field

[0001] This application relates to the field of power electronics, and more specifically, to a method and apparatus for rectifier control. Background Technology

[0002] An ideal power system continuously provides users with stable and reliable electrical energy at rated voltage and a constant frequency (50Hz or 60Hz) using a standard sine wave. However, with the development of industrial technology and production needs, especially the advancements in power electronics technology in recent decades, most of the electrical energy provided by the power system undergoes secondary conversion using power electronics technology before being supplied to electrical equipment.

[0003] Due to the impedance on the transmission line, a weak grid phenomenon may occur, which may cause the rectifier to be unable to output a stable current when connected to the weak grid. Summary of the Invention

[0004] This application provides a method and apparatus for rectifier control, which enables the rectifier to output a stable current when connected to a weak power grid.

[0005] The first aspect of this application provides a method for controlling a rectifier, the rectifier being used to convert a three-phase AC signal into a DC signal, the method comprising: determining active power and reactive power based on sampled voltage and sampled current of the three-phase AC signal; determining a given active power based on a given voltage and sampled voltage of the DC signal; determining a target voltage vector for model predictive control based on the active power, the reactive power, the given active power, and an injected damped Hamiltonian dissipation model; performing model predictive control based on the target voltage vector to obtain a control signal for the rectifier; and controlling the rectifier based on the control signal.

[0006] In the embodiments of this application, a damped Hamiltonian dissipation model is combined with model predictive control to control the rectifier. Due to the damping, the Hamiltonian dissipation model can weaken the transmission line impedance, thereby enhancing system stability. At the same time, model predictive control can compensate for the slightly slower dynamic response of the Hamiltonian dissipation model, accelerating the system response time. Therefore, the above scheme can effectively control the rectifier to output a stable current.

[0007] In some possible embodiments, determining the target voltage vector for model predictive control based on the active power, the reactive power, the given active power, and the Hamiltonian dissipation model with injection damping includes: determining the d-axis and q-axis components of the target voltage vector based on the active power, the reactive power, the given active power, and the Hamiltonian dissipation model with injection damping; and converting the d-axis and q-axis components of the target voltage vector into the α-axis and β-axis components of the target voltage vector through an inverse Parker transformation.

[0008] In this embodiment, the target voltage vector for model predictive control is determined by injecting a damped Hamiltonian dissipation model, which can be used to accelerate the system response through rolling optimization of model predictive control.

[0009] In some possible embodiments, the d-axis component V of the target voltage vector d and q-axis component V q They are respectively:

[0010]

[0011]

[0012] in, E α E β For the voltage in an orthogonal stationary coordinate system, R i For damping injection, P* is the given active power, P is the active power, Q* is the given reactive power, Q is the reactive power, ω is the angular frequency of the three-phase AC signal, and L g R is the inductance value of the three-phase AC reactor for the three-phase AC signal. g The resistance value of the three-phase AC reactor for the three-phase AC signal.

[0013] In this embodiment, the line impedance can be weakened and the system stability enhanced by injecting damping into the state equation after the common access point.

[0014] In some possible embodiments, the step of performing model predictive control based on the target voltage vector to obtain the control signal of the rectifier includes: determining the voltage vector closest to the target voltage vector; and using the control signal corresponding to the voltage vector closest to the target voltage vector as the control signal of the rectifier.

[0015] In this embodiment of the application, after obtaining the target voltage vector, the voltage vector closest to the target voltage vector is found within a specified range, and the control signal corresponding to this voltage vector is applied to the rectifier without the need for other modulation strategies. It is not sensitive to the grid frequency and can remain stable under operating conditions with large frequency variations.

[0016] In some possible embodiments, the control signals of the rectifier satisfy:

[0017]

[0018] Where S represents the control signal. A function of S, S x ∈{0,1},x={a,b,c},V α V β Let α and β be the α-axis components and β-axis components of the target voltage vector.

[0019] Based on the above scheme, the voltage vector closest to the target voltage vector can be determined, and thus the control signal of the rectifier can be obtained.

[0020] In some possible embodiments, determining the active power and reactive power based on the sampled voltage and sampled current of the three-phase AC signal includes: converting the sampled voltage and sampled current of the three-phase AC signal into an orthogonal stationary coordinate system voltage and an orthogonal stationary coordinate system current through a Clarke transform; and determining the active power and the reactive power based on the orthogonal stationary coordinate system voltage and the orthogonal stationary coordinate system current.

[0021] In the embodiments of this application, the voltage and current values ​​of the three-phase AC signal and the voltage and current values ​​of the orthogonal stationary coordinate system can be converted to each other through Clarke transformation.

[0022] In some possible embodiments, the active power P and reactive power Q are respectively:

[0023] P = E α *I α +E β *I β Q = E β *I α -E α *I β

[0024] Among them, E α and E β The voltage of the orthogonal stationary coordinate system; I α and I β Let be the current in the orthogonal stationary coordinate system.

[0025] In the embodiments of this application, the active power P and reactive power Q are further obtained from the voltage and current values ​​in the orthogonal stationary coordinate system obtained after Clark transformation, so as to be introduced into the Hamiltonian dissipation model with injection damping to obtain the target voltage vector.

[0026] In some possible embodiments, determining the given active power based on the given voltage and the sampled voltage of the DC signal includes: determining the given active power based on the given voltage and the sampled voltage of the DC signal, and a proportional-integral controller.

[0027] In this embodiment of the application, a given active power is calculated based on the system voltage outer loop proportional-integral controller. The given active power value is the stable value of active power after a period of time.

[0028] In some possible embodiments, the given active power is the output of the proportional-integral controller, and the proportional-integral transfer function of the proportional-integral controller is:

[0029]

[0030] The input of the proportional-integral controller is... and V dc The given voltage and sampling voltage of the DC signal are respectively; K p K i These are the proportional gain and integral gain, respectively.

[0031] A second aspect of this application provides a rectifier control apparatus, wherein the rectifier is used to convert a three-phase AC signal into a DC signal. The apparatus includes: an acquisition module for acquiring sampled voltages and sampled currents of the three-phase AC signal and a given voltage and sampled voltage of the DC signal; a processing module for determining active power and reactive power based on the sampled voltages and sampled currents of the three-phase AC signal; determining a given active power based on the given voltage and sampled voltage of the DC signal; determining a target voltage vector for model predictive control based on the active power, the reactive power, the given active power, and an injected damped Hamiltonian dissipation model; performing model predictive control based on the target voltage vector to obtain a control signal for the rectifier; and a control module for controlling the rectifier according to the control signal.

[0032] In some possible embodiments, the processing module is configured to: determine the d-axis and q-axis components of the target voltage vector based on the active power, the reactive power, the given active power, and the Hamiltonian dissipation model of the injected damping; and convert the d-axis and q-axis components of the target voltage vector into the α-axis and β-axis components of the target voltage vector according to the inverse Park transformation.

[0033] In some possible embodiments, the α-axis component and β-axis component of the target voltage vector are respectively:

[0034]

[0035]

[0036] in, E α E β For the voltage in an orthogonal stationary coordinate system, R i For damping injection, P* is the given active power, P is the active power, Q* is the given reactive power, Q is the reactive power, ω is the angular frequency of the three-phase AC signal, and L g R is the inductance value of the three-phase AC reactor for the three-phase AC signal. g The resistance value of the three-phase AC reactor for the three-phase AC signal.

[0037] In some possible embodiments, the processing module is configured to: determine the voltage vector closest to the target voltage vector; and use the control signal corresponding to the voltage vector closest to the target voltage vector as the control signal of the rectifier.

[0038] In some possible embodiments, the control signals of the rectifier satisfy:

[0039]

[0040] Where S represents the control signal. A function of S, S x ∈{0,1},x={a,b,c},V α V β Let α and β be the α-axis components and β-axis components of the target voltage vector.

[0041] In some possible embodiments, the processing module is configured to: convert the sampled voltage and sampled current of the three-phase AC signal into orthogonal stationary coordinate system voltage and orthogonal stationary coordinate system current through Clarke transform; and determine the active power and the reactive power based on the orthogonal stationary coordinate system voltage and the orthogonal stationary coordinate system current.

[0042] In some possible embodiments, the active power P and reactive power Q are respectively:

[0043] P = E α *I α +E β *I β Q = E β *I α -E α *I β

[0044] Among them, E α and E β The voltage of the orthogonal stationary coordinate system; I α and I β Let be the current in the orthogonal stationary coordinate system.

[0045] In some possible embodiments, the processing module is configured to: determine the given active power based on the given voltage and sampled voltage of the DC signal, and the proportional-integral controller.

[0046] In some possible embodiments, the given active power is the output of the proportional-integral controller, and the proportional-integral transfer function of the proportional-integral controller is:

[0047]

[0048] The input of the proportional-integral controller is... and V dc The given voltage and sampling voltage of the DC signal are respectively; K p K i These are the proportional gain and integral gain, respectively.

[0049] A third aspect of this application provides a rectifier control apparatus, including a processor and a memory, the memory for storing a computer program, and the processor for calling the computer program to execute the methods described in the first aspect and any possible implementation thereof.

[0050] A fourth aspect of this application provides a computer-readable storage medium for storing a computer program for performing the methods of the first aspect and any possible implementation thereof. Attached Figure Description

[0051] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0052] Figure 1 This is a schematic diagram illustrating an application scenario of the rectifier control method disclosed in an embodiment of this application;

[0053] Figure 2 This is a schematic flowchart of a rectifier control method disclosed in an embodiment of this application;

[0054] Figure 3 This is an architecture diagram of a rectifier control method disclosed in an embodiment of this application;

[0055] Figure 4 This is a schematic flowchart of a rectifier control method disclosed in an embodiment of this application;

[0056] Figure 5 This is a schematic block diagram of a rectifier control device disclosed in an embodiment of this application.

[0057] The accompanying drawings are not drawn to scale. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0059] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0060] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0061] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "attachment," and "installation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0062] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0063] Due to the impedance of transmission lines, weak power grids frequently occur in remote areas and rural areas. Therefore, when the rectifier is running, the voltage at its grid connection port is not equal to the actual grid voltage, leading to phenomena such as resonance and frequency instability. Currently, there are two main methods to address this phenomenon: one is to modify the rectifier itself, which generates harmonics and reactive power. However, traditional rectifiers cannot suppress grid harmonics caused by other loads in the power grid. The other method is to add harmonic filtering and reactive power compensation devices to the power system. However, existing methods, which involve adding repetitive controllers, are extremely sensitive to the grid frequency. Once the grid frequency is not 50Hz, the control performance deteriorates significantly. Furthermore, repetitive control requires specific data allocation, resulting in significant memory consumption and considerable control difficulty.

[0064] Therefore, this application provides a rectifier control method that combines a damped Hamiltonian dissipation model with model predictive control to control the rectifier. Due to damping injection, the Hamiltonian dissipation model can weaken the transmission line impedance, thereby enhancing system stability. At the same time, model predictive control can compensate for the slow dynamic response of the Hamiltonian dissipation model, accelerating the system response time, thus effectively controlling the rectifier to output a stable current.

[0065] Model predictive control is a special type of control. Its current control action is obtained by solving a finite-time open-loop optimal control problem at each sampling instant. The current state of the process serves as the initial state of the optimal control problem, and the optimal control sequence obtained only implements the first control action. Generally speaking, model prediction has the following advantages: (1) It does not require high model accuracy, is easy to model, and the process description can be obtained from simple experiments; (2) It uses a non-minimization model, resulting in better system robustness and stability; (3) It adopts a rolling optimization strategy instead of global one-time optimization, which can promptly compensate for uncertainties caused by model mismatch, distortion, interference, etc., resulting in better dynamic performance.

[0066] Damping is the ability of a vibrating system to convert a portion of the energy generated during each vibration cycle into another form of energy; simply put, it reduces the amplitude of oscillations in the system. High damping accelerates the decrease in system amplitude, leading to a return to steady state. Specifically, this manifests as smaller vibrations, faster cessation of vibration, and more stable cessation of vibration.

[0067] Hamilton's principle states that when the system q I Evolved to q F Its true trajectory is always the condition under which the action I takes an extreme value. Specifically, when the generalized coordinates and velocity are given an infinitesimal perturbation... δ (dqi / dt The action is very stable and undisturbed, i.e., δ I =0. Therefore, Hamilton's principle is essentially the principle of orbital stability; the particle moves from q... I Exercise to q F The Hamiltonian principle always chooses the most stable path. It applies not only to point systems with finite degrees of freedom but also to point systems with infinite degrees of freedom. In dissipative systems, the Hamiltonian principle can be used to construct Hamiltonian dissipative models to solve complex problems within these systems.

[0068] Figure 1 This is a schematic diagram illustrating an application scenario of a technical solution according to an embodiment of this application. For example... Figure 1 As shown, the rectifier includes six switches Q1-Q6 for converting three-phase AC signals into DC signals. This rectifier is also known as a Pulse Width Modulation (PWM) rectifier. In this embodiment, the control signal for the rectifier is obtained based on the injected damped Hamiltonian dissipation model combined with model predictive control, so as to make the rectifier output a stable current and overcome the influence of a weak power grid.

[0069] Figure 2 This is a schematic flowchart of a rectifier control method disclosed in an embodiment of this application. This method can be used to control... Figure 1 The rectifier in the middle.

[0070] 201. Based on the sampling voltage and sampling current of the three-phase AC signal, determine the active power and reactive power.

[0071] Three-phase AC signal refers to the AC electrical signal provided by the power grid. The sampling voltage and sampling current of three-phase AC signal refer to the sampled values ​​of the voltage and current of the three-phase AC signal.

[0072] Active power refers to the alternating current energy actually generated or consumed per unit time; it is the average power over the cycle. Reactive power, on the other hand, refers to the maximum energy exchange rate between the power source and reactive components (such as capacitors and inductors) in an AC circuit with reactance, even though the average power of the electric or magnetic field is zero throughout the entire cycle.

[0073] 202. Determine the given active power based on the given voltage and sampling voltage of the DC signal.

[0074] The given voltage of a DC signal refers to the target value of the voltage of the DC signal converted from the three-phase AC signal by the rectifier, that is, the value at which the circuit voltage stabilizes after a period of time, which can also be called the voltage setpoint.

[0075] The sampling voltage of a DC signal refers to the sampled value of the DC signal voltage converted from the three-phase AC signal by the rectifier.

[0076] Given active power refers to the stable value of active power after a period of time, that is, the target value of active power, which can also be called the given active power.

[0077] 203. Based on the active power, reactive power, and given active power, as well as the Hamiltonian dissipation model with injected damping, determine the target voltage vector for model predictive control.

[0078] A Hamiltonian dissipation model with injection damping is constructed using Hamilton's principle. The target voltage vector is obtained from the aforementioned active power, reactive power, and given active power. The given reactive power involved in the calculation can be a set value, such as 0. This given reactive power is the value at which the reactive power stabilizes after a period of time, i.e., the target value of the reactive power, which can also be called the reactive power setpoint.

[0079] The target voltage vector, also known as the optimal voltage vector, is the voltage vector corresponding to the optimal control in model predictive control.

[0080] 204. Based on the target voltage vector, model predictive control is performed to obtain the control signal for the rectifier.

[0081] 205, control the rectifier according to the control signal.

[0082] In this embodiment, a damped Hamiltonian dissipation model is combined with model predictive control to control the rectifier. Due to the damping, the Hamiltonian dissipation model can weaken the transmission line impedance, thereby enhancing system stability. At the same time, model predictive control can compensate for the slightly slower dynamic response of the Hamiltonian dissipation model, accelerating the system response time, thus effectively controlling the rectifier to output a stable current.

[0083] Figure 3 This is an architecture diagram of a rectifier control method disclosed in an embodiment of this application. Figure 4 This is a schematic flowchart of a rectifier control method disclosed in an embodiment of this application. Refer to the following... Figure 3 and Figure 4 The rectifier control method of the present application embodiments will be further described.

[0084] 401, sampling voltage E of three-phase AC signal acquisition. a E b E c The sampling current I of the three-phase AC signal a I b I c and the sampling voltage V of the DC signal dc .

[0085] 402, the sampling voltage E of the three-phase AC signal a E b E c and sampling current I a I b I c Converted to voltage E in an orthogonal stationary coordinate system via Clarke transformation α E β Current I in orthogonal stationary coordinate system α I β .

[0086] In the embodiments of this application, the Clarke transform converts the time-domain components of a three-phase system (in the abc coordinate system) into two components in an orthogonal stationary coordinate system (αβ). The αβ and abc components of the vector can be converted to each other through the Clarke transform and the inverse Clarke transform. The difference is that the αβ and abc components are orthogonal to each other and are 90° out of phase, while the abc components are 220° out of phase. Both of these components are still AC quantities.

[0087] Alternatively, the Clarke transform of current and voltage is:

[0088]

[0089]

[0090] 403, based on the given voltage of the DC signal and sampling voltage V dc Determine the given active power P*.

[0091] Optionally, it can be based on the given voltage of the DC signal. Sampling voltage V dc And a proportional integral controller (PI) is used to determine the given active power P*.

[0092] Proportional-integral control (PIC) uses the given value and the actual output value to form the control deviation. The deviation is then linearly combined according to the proportion, integral and derivative to form the control quantity, which controls the controlled object.

[0093] Based on the given voltage of the DC signal Sampling voltage V dc The proportional-integral controller determines the given active power P*. This method has a simple algorithm, good robustness, and high reliability.

[0094] For example, given the active power P* as the output of the proportional-integral (PI) controller, the PI transfer function of the PI controller is:

[0095]

[0096] Proportional Gain K p and integral gain K i The two parameters constitute the time constant of the closed-loop controller. This time constant is equivalent to the time constant of the output load, and they cancel each other out in the structural transfer function of the closed-loop automatic control system, causing its automatic load adjustment process to converge in steady state. If the proportional gain K p and integral gain K i If the time constant of the regulator does not match the time constant of the output load, the steady-state process of the regulating system will oscillate or diverge, and it will not be able to work properly.

[0097] 404, according to the voltage E in the orthogonal stationary coordinate system α E β Current I in orthogonal stationary coordinate system α I β Determine the active power P and reactive power Q.

[0098] Optionally, the active power P and reactive power Q are respectively:

[0099] P = E α *I α +E β *I β Q = E β *I α -Eα *I β

[0100] In the above scheme, the voltage value E in the orthogonal stationary coordinate system is obtained according to the Clark transformation. α E β and current value I α I β This allows us to obtain the active power P and reactive power Q, which can then be incorporated into the injected damping R. i The Hamiltonian dissipation model.

[0101] 405, based on active power P, reactive power Q, and a given active power P*, and the injected damping R i The Hamiltonian dissipation model is used to determine the d-axis component V of the target voltage vector. d and q-axis component V q .

[0102] For this rectifier, the injection damping R is constructed using Hamilton's principle. i The Hamiltonian dissipation model yields the state equations. Substituting the active power P, reactive power Q, given active power P*, and given reactive power Q* into the state equations, we obtain the d-axis component V of the target voltage vector. d and q-axis component V q .

[0103] For example, the d-axis component V of the target voltage vector d and q-axis component V q They are respectively:

[0104]

[0105]

[0106] in, ω is the angular frequency of the three-phase AC signal, used to represent how fast the three-phase AC signal changes. L g R is the inductance value of a three-phase AC reactor for a three-phase AC signal. g The resistance value of the three-phase AC reactor is for a three-phase AC signal.

[0107] In the above scheme, the line impedance can be weakened and the system stability enhanced by injecting damping into the state equation after the common access point.

[0108] 406, the d-axis component V of the target voltage vector d and q-axis component V q The α-axis component V of the target voltage vector is transformed by the inverse Park transformation. α and β-axis component V β .

[0109] The d-axis component V of the vector d and q-axis component V q It is the voltage vector α-axis component V α and β-axis component V β The rotational transformations of the two can be performed using the Parker transformation and inverse Parker transformation, requiring the current grid voltage angle θ. The difference lies in the d-axis component V of the vector. d and q-axis component V q It is DC, and the voltage vector α-axis component V α and β-axis component V β It's communication.

[0110] The Parker transformation is a commonly used coordinate transformation for analyzing the operation of synchronous motors. It projects the three-phase currents abc of the stator substrate onto the direct axis (d-axis), the quadrature axis (q-axis), and the zero axis (0-axis) perpendicular to the dq plane as the rotor rotates, thereby achieving the diagonalization of the electronic inductance matrix, that is, transforming the abc coordinate system to the dq coordinate system.

[0111] Alternatively, the inverse Park transformation formula for the voltage vector is:

[0112]

[0113] 407, determine the voltage vector closest to the target voltage vector, and output the control signal S of the rectifier.

[0114] The control signal S of the output rectifier is the control signal S corresponding to the voltage vector that is closest to the target voltage vector.

[0115] Optionally, the control signal S of the rectifier satisfies:

[0116]

[0117]

[0118]

[0119] There are eight states S, corresponding to eight voltage vectors. Based on this, model predictive control can be performed by finding the voltage vector among the eight that is closest to the target voltage vector, thus obtaining its corresponding control signal S. opt Output the control signal S opt This is directed to the rectifier, thereby controlling the rectifier to output a stable current.

[0120] The control method used in this application is passive control. Due to its damping injection, passive control can counteract the effects of imbalances from the source and load ends, such as constant power loads and weak power grids. The object model used in model prediction focuses on accurate prediction of the controlled object. The control signal is obtained by combining a damped Hamiltonian dissipation model with model predictive control. This control signal acts directly on the rectifier without requiring a modulation strategy, thus improving response speed. Only one damping coefficient needs to be tuned, making control parameter adjustment easy. Furthermore, it does not require grid frequency information throughout the process, is insensitive to grid frequency, and can maintain stability under conditions of large frequency variations.

[0121] The rectifier control method of the present application embodiment has been described above. The rectifier control device of the present application embodiment is described below. For the parts not described in detail, please refer to the foregoing embodiments.

[0122] Figure 5 This is a schematic diagram of a rectifier control device disclosed in an embodiment of this application. In the embodiments of this application, the rectifier control device may include an acquisition module 501, a processing module 502, and a control module 503.

[0123] The acquisition module 501 is used to acquire the sampled voltage and sampled current of the three-phase AC signal and the given voltage and sampled voltage of the DC signal;

[0124] The processing module 502 can be used to determine the active power and reactive power based on the sampled voltage and sampled current of the three-phase AC signal; determine the given active power based on the given voltage and sampled voltage of the DC signal; determine the target voltage vector for model predictive control based on the active power, reactive power, and given active power, as well as the Hamiltonian dissipation model with injected damping; and perform model predictive control based on the target voltage vector to obtain the control signal for the rectifier.

[0125] The control module 503 can be used to control the rectifier according to the control signal.

[0126] In one embodiment of this application, the processing module 502 is used to determine a given active power based on the given voltage and sampled voltage of the DC signal, as well as the proportional-integral controller.

[0127] In one embodiment of this application, the processing module 502 is used to convert the sampled voltage and sampled current of the three-phase AC signal into orthogonal stationary coordinate system voltage and orthogonal stationary coordinate system current through Clark transformation; and to determine the active power and reactive power based on the orthogonal stationary coordinate system voltage and orthogonal stationary coordinate system current.

[0128] In one embodiment of this application, the processing module 502 is used to determine the d-axis component and q-axis component of the target voltage vector based on the active power, reactive power, and given active power, as well as the Hamiltonian dissipation model with injected damping; and to convert the d-axis component and q-axis component of the target voltage vector into the α-axis component and β-axis component of the target voltage vector according to the inverse Park transformation.

[0129] In one embodiment of this application, the processing module 502 is further configured to determine the voltage vector closest to the target voltage vector; and use the control signal corresponding to the voltage vector closest to the target voltage vector as the control signal of the rectifier.

[0130] This application also provides another rectifier control device, which includes a memory and a processor, wherein the memory is used to store instructions, and the processor is used to read the instructions and execute the methods of the aforementioned embodiments of this application based on the instructions.

[0131] This application also provides a readable storage medium for storing a computer program for executing the methods described in the foregoing embodiments of this application.

[0132] In this embodiment, by combining the injected damped Hamiltonian dissipation model with model predictive control, the rectifier can be controlled, which can weaken the transmission line impedance, enhance system stability, and accelerate the system response time, thereby effectively controlling the rectifier to output a stable current.

[0133] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for rectifier control, characterized in that, The rectifier is used to convert a three-phase AC signal into a DC signal, and the method includes: Based on the sampling voltage and sampling current of the three-phase AC signal, determine the active power and reactive power; The given active power is determined based on the given voltage and the sampled voltage of the DC signal; Based on the active power, the reactive power, and the given active power, as well as the Hamiltonian dissipation model with injected damping, the target voltage vector for model predictive control is determined. Model predictive control is performed based on the target voltage vector to obtain the control signal for the rectifier; The rectifier is controlled according to the control signal; The step of performing model predictive control based on the target voltage vector to obtain the control signal for the rectifier includes: Determine the voltage vector that is closest to the target voltage vector; The control signal corresponding to the voltage vector closest to the target voltage vector is used as the control signal for the rectifier; The control signal of the rectifier satisfies: in, S Indicates control signal, for S The function, , , Let α and β be the α-axis components and β-axis components of the target voltage vector.

2. The method according to claim 1, characterized in that, The step of determining the target voltage vector for model predictive control based on the active power, the reactive power, the given active power, and the Hamiltonian dissipation model with injected damping includes: Based on the active power, the reactive power, and the given active power, as well as the Hamiltonian dissipation model of the injected damping, determine the d-axis component and q-axis component of the target voltage vector; The d-axis and q-axis components of the target voltage vector are converted into the α-axis and β-axis components of the target voltage vector through an inverse Parker transformation.

3. The method according to claim 2, characterized in that, The d-axis component of the target voltage vector V d and q-axis components V q They are respectively: in, , , Voltage in an orthogonal stationary coordinate system R i To inject damping, P* Given the active power, P The active power is... Q* Given reactive power, Q The reactive power is... The angular frequency of the three-phase AC signal ，L g The inductance value of the three-phase AC reactor for the three-phase AC signal. ，R g The resistance value of the three-phase AC reactor for the three-phase AC signal.

4. The method according to claim 1, characterized in that, The step of determining active power and reactive power based on the sampled voltage and sampled current of the three-phase AC signal includes: The sampled voltage and sampled current of the three-phase AC signal are converted into orthogonal stationary coordinate system voltage and orthogonal stationary coordinate system current through Clarke transformation; The active power and the reactive power are determined based on the voltage and current in the orthogonal stationary coordinate system.

5. The method according to claim 4, characterized in that, The active power and the reactive power They are respectively: in, and The voltage in the orthogonal stationary coordinate system; and Let be the current in the orthogonal stationary coordinate system.

6. The method according to claim 1, characterized in that, The step of determining the given active power based on the given voltage and the sampled voltage of the DC signal includes: The given active power is determined based on the given voltage and sampling voltage of the DC signal, and the proportional-integral controller.

7. The method according to claim 6, characterized in that, The given active power is the output of the proportional-integral controller, and the proportional-integral transfer function of the proportional-integral controller is: The input of the proportional-integral controller is... and These are the given voltage and the sampling voltage of the DC signal, respectively; , These are the proportional gain and integral gain, respectively.

8. A rectifier control device, characterized in that, The rectifier is used to convert a three-phase AC signal into a DC signal, and the device includes: The acquisition module is used to acquire the sampling voltage and sampling current of the three-phase AC signal and the given voltage and sampling voltage of the DC signal; The processing module determines the active power and reactive power based on the sampled voltage and sampled current of the three-phase AC signal; determines the given active power based on the given voltage and sampled voltage of the DC signal; determines the target voltage vector for model predictive control based on the active power, the reactive power, the given active power, and the Hamiltonian dissipation model with injected damping; and performs model predictive control based on the target voltage vector to obtain the control signal for the rectifier. The control module is used to control the rectifier according to the control signal; The processing module is used for: Determine the voltage vector that is closest to the target voltage vector; The control signal corresponding to the voltage vector closest to the target voltage vector is used as the control signal for the rectifier; The control signal of the rectifier satisfies: in, S Indicates control signal, for S The function, , , Let α and β be the α-axis components and β-axis components of the target voltage vector.

9. The apparatus according to claim 8, characterized in that, The processing module is used for: Based on the active power, the reactive power, and the given active power, as well as the Hamiltonian dissipation model of the injected damping, determine the d-axis component and q-axis component of the target voltage vector; According to the inverse Parker transformation, the d-axis and q-axis components of the target voltage vector are converted into the α-axis and β-axis components of the target voltage vector.

10. The apparatus according to claim 9, characterized in that, The d-axis component of the target voltage vector V d and q-axis components V q They are respectively: in, , , Voltage in an orthogonal stationary coordinate system R i To inject damping, P* For the given active power, P The active power is... Q* Given reactive power, Q The reactive power is... The angular frequency of the three-phase AC signal ，L g The inductance value of the three-phase AC reactor for the three-phase AC signal. ，R g The resistance value of the three-phase AC reactor for the three-phase AC signal.

11. The apparatus according to claim 8, characterized in that, The processing module is used for: The sampled voltage and sampled current of the three-phase AC signal are converted into orthogonal stationary coordinate system voltage and orthogonal stationary coordinate system current through Clarke transformation; The active power and the reactive power are determined based on the voltage and current in the orthogonal stationary coordinate system.

12. The apparatus according to claim 11, characterized in that, The active power and reactive power They are respectively: in, and The voltage in the orthogonal stationary coordinate system; and Let be the current in the orthogonal stationary coordinate system.

13. The apparatus according to claim 8, characterized in that, The processing module is used for: The given active power is determined based on the given voltage and sampling voltage of the DC signal, and the proportional-integral controller.

14. The apparatus according to claim 13, characterized in that, The given active power is the output of the proportional-integral controller, and the proportional-integral transfer function of the proportional-integral controller is: The input of the proportional-integral controller is... and These are the given voltage and the sampling voltage of the DC signal, respectively; , These are the proportional gain and integral gain, respectively.

15. A rectifier control device, characterized in that, It includes a processor and a memory, the memory being used to store a computer program, and the processor being used to invoke the computer program to execute the method of any one of claims 1 to 7.

16. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program for performing the method according to any one of claims 1 to 7.

Images