Control methods and devices for grid-connected wind turbine generators

Abstract

A control method and apparatus for a grid-connected wind turbine generator set are provided. The control method includes: acquiring the positive-sequence components of the three-phase voltage of the grid-connected wind turbine generator set; calculating the AC voltage amplitude of the grid-connected wind turbine generator set based on the positive-sequence components of the three-phase voltage; determining the effective value of the positive-sequence internal potential of the grid-connected wind turbine generator set based on the reactive power command reference value, the AC voltage amplitude, and the rated AC voltage effective value; acquiring the positive-sequence phase angle of the grid-connected wind turbine generator set; calculating the positive-sequence internal potential of the grid-connected wind turbine generator set based on the effective value of the positive-sequence internal potential and the positive-sequence phase angle; and using the positive-sequence internal potential as a modulation reference wave for the power module of the grid-connected wind turbine generator set to control the grid-connected wind turbine generator set.

Description

Technical Field

[0001] This disclosure relates to the field of wind power generation technology. More specifically, this disclosure relates to a control method and apparatus for a grid-connected wind turbine generator set. Background Technology

[0002] With the continuous growth of wind power installed capacity, the proportion of wind power generation in the power system is constantly increasing. Traditional wind power generation based on power control strategies lacks the ability to build and support the power grid. Moreover, the lack of rotational inertia and limited reserve capacity in power electronic renewable energy systems leads to a decline in grid stability. The new grid characterized by "high proportion of renewable energy and high proportion of power electronic equipment" places higher demands on the support of wind power. To address this issue, grid-based renewable energy control technology has been proposed, enabling power electronic devices to possess the inertia and damping characteristics of synchronous generators operating in grid, as well as steady-state characteristics such as active power frequency regulation and reactive power voltage regulation. Grid-based renewable energy control technology typically introduces synchronous machine simulation algorithms into the power control stage of the converter, simulating the rotor motion equations of the synchronous generator to characterize the droop characteristics of active power and frequency. Therefore, the detection and calculation of the power stage are particularly important, directly affecting the system control stability.

[0003] Most current power synchronization loops do not consider the impact of active power detection instability on power-frequency droop characteristics under unbalanced operating conditions, and do not use first-order low-pass filters to filter the active power detection stage. However, first-order low-pass filters have problems such as slow response speed, poor stability, and inability to eliminate secondary ripple under unbalanced operating conditions. Summary of the Invention

[0004] An exemplary embodiment of this disclosure provides a control method and apparatus for a grid-connected wind turbine generator set, which avoids system power oscillation caused by secondary pulsations introduced by negative sequence components under unbalanced voltage conditions through the control of unbalanced voltage.

[0005] According to an exemplary embodiment of this disclosure, a control method for a grid-connected wind turbine generator set is provided, comprising: acquiring the positive-sequence components of the three-phase voltage of the grid-connected wind turbine generator set; calculating the AC voltage amplitude of the grid-connected wind turbine generator set based on the positive-sequence components of the three-phase voltage; determining the effective value of the positive-sequence internal potential of the grid-connected wind turbine generator set based on the reactive power command reference value, the AC voltage amplitude, and the effective value of the rated AC voltage of the grid-connected wind turbine generator set; acquiring the positive-sequence phase angle of the grid-connected wind turbine generator set; calculating the positive-sequence internal potential of the grid-connected wind turbine generator set based on the effective value of the positive-sequence internal potential and the positive-sequence phase angle; and using the positive-sequence internal potential as a modulation reference wave for the power module of the grid-connected wind turbine generator set to control the grid-connected wind turbine generator set.

[0006] Optionally, the control method may further include: acquiring the positive-sequence components of the three-phase current of the grid-connected wind turbine generator set; updating the theoretical value of the positive-sequence active power of the grid-connected wind turbine generator set based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase current of the grid-connected wind turbine generator set; and performing virtual control of the synchronous generator rotor motion equation of the grid-connected wind turbine generator set based on the updated theoretical value of the positive-sequence active power of the grid-connected wind turbine generator set.

[0007] Optionally, the control method may further include: acquiring the positive-sequence components of the three-phase current of the grid-connected wind turbine generator set; updating the theoretical value of the positive-sequence reactive power of the grid-connected wind turbine generator set based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase current; and performing excitation simulation control of the synchronous generator of the grid-connected wind turbine generator set based on the updated theoretical value of the positive-sequence reactive power and the positive-sequence components of the three-phase voltage.

[0008] Optionally, calculating the positive-sequence internal potential of the grid-connected wind turbine generator based on its effective value and positive-sequence phase angle may include: based on the formula Calculate the positive-sequence internal potential of the grid-connected wind turbine generator set, where e abc+ =[e a+ e b+ e c+ ] T This represents the positive-sequence internal potential. θ represents the effective value of the positive sequence potential. + The positive sequence phase angle is represented by T, which represents the transpose.

[0009] Optionally, updating the theoretical value of the positive-sequence active power of the grid-connected wind turbine generator based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase current can include: based on the formula Calculate the updated theoretical value of the positive-sequence active power of the grid-connected wind turbine generator set, where i a+ i b+ i c+ The positive sequence component of each phase current in the three-phase current is represented by T, which represents the transpose, and P is the positive sequence component of each phase current. + = <e abc+ i abc+ > represents the theoretical value of the positive-sequence active power. <e abc+ i abc+ > indicates e abc+ and i abc+ The inner product, e abc+i represents the positive-sequence internal potential. abc+ θ represents the positive sequence component of the three-phase current. + This represents the positive sequence phase angle.

[0010] Optionally, updating the theoretical value of the positive-sequence reactive power of the grid-connected wind turbine generator based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase currents can include: based on the formula Calculate the theoretical value of the updated positive-sequence reactive power of the grid-connected wind turbine generator set, where Q+= <e abc+⊥ i abc+ > represents the theoretical value of the positive-sequence reactive power. θ represents the effective value of the positive sequence potential. + i represents the positive sequence phase angle. a+ i b+ i c+ This represents the positive sequence component of each phase current in the three-phase current, where T represents the transpose, and i abc+ This represents the positive sequence component of the three-phase current. <e abc+⊥ i abc+ > indicates e abc+⊥ and i abc+ The inner product, e abc+⊥ This represents the orthogonal quantity that indicates a 90-degree phase shift in the positive sequence potential.

[0011] Optionally, obtaining the positive-sequence components of the three-phase voltage of the grid-connected wind turbine generator may include: obtaining the positive-sequence components of the three-phase voltage based on a Kalman filter.

[0012] Optionally, determining the positive-sequence internal potential effective value of the grid-type wind turbine generator based on the reactive power command reference value, AC voltage amplitude, and rated AC voltage effective value of the grid-type wind turbine generator may include: calculating the positive-sequence internal potential effective value of the grid-type wind turbine generator based on the AC voltage amplitude, rated AC voltage effective value, voltage droop coefficient, reactive power command reference value, and theoretical value of positive-sequence reactive power of the grid-type wind turbine generator.

[0013] According to an exemplary embodiment of this disclosure, a control device for a voltage source type wind turbine generator set is provided, comprising: a positive sequence component acquisition unit configured to acquire the positive sequence component of the three-phase voltage of the grid-type wind turbine generator set; a voltage amplitude calculation unit configured to calculate the AC voltage amplitude of the grid-type wind turbine generator set based on the positive sequence component of the three-phase voltage; an internal potential effective value determination unit configured to determine the positive sequence internal potential effective value of the grid-type wind turbine generator set based on the reactive power command reference value, the AC voltage amplitude, and the rated AC voltage effective value of the grid-type wind turbine generator set; a phase angle acquisition unit configured to acquire the positive sequence phase angle of the grid-type wind turbine generator set; an internal potential calculation unit configured to calculate the positive sequence internal potential of the grid-type wind turbine generator set based on the positive sequence internal potential effective value and the positive sequence phase angle; and a first control unit configured to use the positive sequence internal potential as a modulation reference wave for the power module of the grid-type wind turbine generator set to control the grid-type wind turbine generator set.

[0014] Optionally, the control device may be installed in the converter of the grid-type wind turbine generator set.

[0015] Optionally, the control device may further include a second control unit configured to: acquire the positive-sequence components of the three-phase current of the grid-connected wind turbine generator set; update the theoretical value of the positive-sequence active power of the grid-connected wind turbine generator set based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase current of the grid-connected wind turbine generator set; and perform virtual control of the synchronous generator rotor motion equation of the grid-connected wind turbine generator set based on the updated theoretical value of the positive-sequence active power of the grid-connected wind turbine generator set.

[0016] Optionally, the control device may further include a third control unit configured to: acquire the positive-sequence components of the three-phase current of the grid-connected wind turbine generator set; update the theoretical value of the positive-sequence reactive power of the grid-connected wind turbine generator set based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase current of the grid-connected wind turbine generator set; and perform excitation simulation control of the synchronous generator of the grid-connected wind turbine generator set based on the updated theoretical value of the positive-sequence reactive power of the grid-connected wind turbine generator set and the positive-sequence components of the three-phase voltage.

[0017] Optionally, the internal potential calculation unit can be configured to: calculate based on the formula Calculate the positive-sequence internal potential of the grid-connected wind turbine generator set, where e abc+ =[e a+ e b+ e c+ ] T This represents the positive-sequence internal potential. θ represents the effective value of the positive sequence potential. + The positive sequence phase angle is represented by T, which represents the transpose.

[0018] Optionally, the second control unit can be configured to: based on the formula Calculate the updated theoretical value of the positive-sequence active power of the grid-connected wind turbine generator set, where i a+ i b+ i c+ The positive sequence component of each phase current in the three-phase current is represented by T, which represents the transpose, and P is the positive sequence component of each phase current. + = <e abc+ i abc+ > represents the theoretical value of the positive-sequence active power. <e abc+ i abc+ > indicates e abc+ and i abc+ The inner product, e abc+ i represents the positive-sequence internal potential. abc+ θ represents the positive sequence component of the three-phase current. + This represents the positive sequence phase angle.

[0019] Optionally, the third control unit may be configured to: based on the formula Calculate the theoretical value of the updated positive-sequence reactive power of the grid-connected wind turbine generator set, where Q + = <e abc+⊥ i abc+ > represents the theoretical value of the positive-sequence reactive power. θ represents the effective value of the positive sequence potential. + i represents the positive sequence phase angle. a+ i b+ i c+ This represents the positive sequence component of each phase current in the three-phase current, where T represents the transpose, and i abc+ This represents the positive sequence component of the three-phase current. <e abc+⊥ i abc+ > indicates e abc+⊥ and i abc+ The inner product, e abc+⊥ This represents the orthogonal quantity that indicates a 90-degree phase shift in the positive sequence potential.

[0020] Optionally, the positive sequence component acquisition unit can be configured to acquire the positive sequence components of the three-phase voltage based on a Kalman filter.

[0021] Optionally, the internal potential effective value determination unit can be configured to: calculate the positive sequence internal potential effective value of the grid-type wind turbine generator based on the AC voltage amplitude, rated AC voltage effective value, voltage droop coefficient, reactive power command reference value, and theoretical value of positive sequence reactive power of the grid-type wind turbine generator.

[0022] According to exemplary embodiments of the present disclosure, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements a control method for a grid-connected wind turbine generator according to exemplary embodiments of the present disclosure.

[0023] According to an exemplary embodiment of the present disclosure, a computing device is provided, comprising: at least one processor; and at least one memory storing a computer program, wherein when the computer program is executed by the at least one processor, a control method for a grid-connected wind turbine generator according to an exemplary embodiment of the present disclosure is implemented.

[0024] Optionally, the computing device may be located in the converter of the grid-type wind turbine generator set.

[0025] According to exemplary embodiments of the present disclosure, a grid-connected wind turbine generator set is provided, including a control device for the grid-connected wind turbine generator set according to exemplary embodiments of the present disclosure or a computing device according to exemplary embodiments of the present disclosure.

[0026] According to an exemplary embodiment of the present disclosure, a computer program product is provided, wherein the instructions in the computer program product are executable by a processor of a computer device to perform a control method for a grid-connected wind turbine generator according to an exemplary embodiment of the present disclosure.

[0027] According to the exemplary embodiments of the present disclosure, a control method and apparatus for a grid-type wind turbine generator set involves acquiring the positive-sequence components of the three-phase voltage of the grid-type wind turbine generator set, calculating the AC voltage amplitude of the grid-type wind turbine generator set based on the positive-sequence components of the three-phase voltage, determining the effective value of the positive-sequence internal potential of the grid-type wind turbine generator set based on the reactive power command reference value, AC voltage amplitude, and rated AC voltage effective value of the grid-type wind turbine generator set, acquiring the positive-sequence phase angle of the grid-type wind turbine generator set, calculating the positive-sequence internal potential of the grid-type wind turbine generator set based on the effective value of the positive-sequence internal potential and the positive-sequence phase angle, and using the positive-sequence internal potential as the modulation reference wave of the power module of the grid-type wind turbine generator set to control the grid-type wind turbine generator set. This control of the unbalanced voltage avoids system power oscillation caused by secondary pulsations introduced by the negative-sequence components under unbalanced voltage conditions.

[0028] Furthermore, according to the exemplary embodiments of the present disclosure, the control method and apparatus for a grid-type wind turbine generator set can first obtain the positive sequence components of the three-phase current of the grid-type wind turbine generator set, update the theoretical value of the positive sequence active power of the grid-type wind turbine generator set based on the effective value of the positive sequence internal potential, the positive sequence phase angle, and the positive sequence components of the three-phase current of the grid-type wind turbine generator set, and then perform virtual control of the synchronous generator rotor motion equation of the grid-type wind turbine generator set based on the updated theoretical value of the positive sequence active power of the grid-type wind turbine generator set.

[0029] Furthermore, according to the control method and apparatus for a grid-type wind turbine generator set according to the exemplary embodiments of this disclosure, the positive sequence components of the three-phase current of the grid-type wind turbine generator set can be obtained first. Based on the effective value of the positive sequence internal potential, the positive sequence phase angle, and the positive sequence components of the three-phase current of the grid-type wind turbine generator set, the theoretical value of the positive sequence reactive power of the grid-type wind turbine generator set is updated. Then, based on the updated theoretical value of the positive sequence reactive power of the grid-type wind turbine generator set and the positive sequence components of the three-phase voltage, the excitation simulation control of the synchronous generator of the grid-type wind turbine generator set is performed.

[0030] Further aspects and / or advantages of the general concept of this disclosure will be set forth in part in the description which follows, and in part will be clear from the description or may be learned by practice of the general concept of this disclosure. Attached Figure Description

[0031] The above and other objects and features of exemplary embodiments of this disclosure will become clearer from the following description taken in conjunction with the accompanying drawings, which exemplarily illustrate the embodiments, wherein:

[0032] Figure 1 A flowchart illustrating a control method for a grid-connected wind turbine generator according to an exemplary embodiment of the present disclosure;

[0033] Figure 2 A schematic diagram of a control system for a grid-connected wind turbine generator according to an exemplary embodiment of the present disclosure is shown.

[0034] Figure 3 A block diagram of a control device for a grid-connected wind turbine generator set according to an exemplary embodiment of the present disclosure is shown.

[0035] Figure 4 A block diagram showing a control device for a grid-connected wind turbine generator according to another exemplary embodiment of the present disclosure; and

[0036] Figure 5 A schematic diagram of a computing device according to an exemplary embodiment of the present disclosure is shown. Detailed Implementation

[0037] Exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings, examples of which are illustrated in the drawings, wherein the same reference numerals always refer to the same components. The embodiments will now be described with reference to the accompanying drawings in order to explain the present disclosure.

[0038] This disclosure proposes a method for controlling unbalanced voltage by extracting positive and negative sequence components based on a Kalman filter. By extracting the positive sequence active power, virtual control of the synchronous generator rotor motion equation is performed. By extracting the positive sequence reactive power and positive sequence voltage, excitation simulation control of the synchronous generator is performed, thereby improving the stability control capability of grid-connected new energy sources under unbalanced operating conditions.

[0039] Figure 1 A flowchart illustrating a control method for a grid-connected wind turbine generator according to an exemplary embodiment of the present disclosure is shown. Figure 2 A schematic diagram of a grid-connected wind turbine generator control system according to exemplary embodiments of the present disclosure is shown. Figure 2 In the middle, v abc+ i represents the positive sequence component of the three-phase voltage of a grid-connected wind turbine generator. abc+ V+ represents the positive sequence component of the three-phase current of a grid-connected wind turbine generator, and V+ represents the amplitude of the AC voltage of the grid-connected wind turbine generator. n This represents the effective value of the rated AC voltage of a grid-connected wind turbine generator set. (D) q P represents the voltage droop factor. set Q represents the active power instruction reference value. set This represents the reactive power command reference value, and Ks represents the reactive power closed-loop integral time constant. e represents the effective value of the positive sequence internal potential of a grid-connected wind turbine generator. abc+ e represents the positive sequence internal potential of a grid-connected wind turbine generator. abc+⊥ P represents the quadrature quantity that indicates a 90-degree phase shift in the positive-sequence potential. + Q represents the positive-sequence component of the active power of a grid-connected wind turbine generator calculated based on instantaneous power theory (i.e., the theoretical value of the positive-sequence active power of the grid-connected wind turbine generator). + This represents the positive-sequence component of the reactive power of a grid-connected wind turbine generator, calculated based on instantaneous power theory (i.e., the theoretical value of the positive-sequence reactive power of a grid-connected wind turbine generator). ω n D represents the rated angular frequency of a grid-connected wind turbine generator. p Js represents the virtual damping coefficient, ω represents the virtual moment of inertia, ω represents the angular frequency of the grid-type wind turbine generator, and θ represents the virtual damping coefficient. + This represents the positive sequence phase angle of a grid-connected wind turbine generator. Q + The initial value of is 0, and the initial value of ω is ω. n P +Its initial value is 0.

[0040] Reference Figure 1 In step S101, the positive sequence components of the three-phase voltage of the grid-type wind turbine generator set are obtained.

[0041] In an exemplary embodiment of this disclosure, when obtaining the positive sequence components of the three-phase voltage of a grid-connected wind turbine generator, the positive sequence components of the three-phase voltage can be obtained based on a Kalman filter.

[0042] Specifically, the Kalman filter incorporates the state space into the recursive process, performs calculations in the time domain, and is easily implemented using a microprocessor. It executes the filtering process by updating the mean and covariance in real time, and uses the least squares method in a recursive manner to obtain the current state estimate of the system using the current measurement value and the observed state variables from the previous time step. Therefore, the Kalman filter is a linear optimal estimator, which has advantages such as high detection accuracy and fast detection speed compared to traditional positive and negative order detection methods.

[0043] In step S102, the AC voltage amplitude of the grid-connected wind turbine generator is calculated based on the positive sequence components of the three-phase voltage, such as... Figure 2 As shown.

[0044] In an exemplary embodiment of this disclosure, when calculating the AC voltage amplitude of the grid-type wind turbine generator based on the positive sequence components of the three-phase voltages, the AC voltage amplitude can be calculated based on the product of the positive sequence components of every two phases of the three-phase voltages.

[0045] For example, through formula Calculate the AC voltage amplitude of the grid-connected wind turbine generator set. Here, the subscript "+" indicates the positive sequence component, V+ indicates the AC voltage amplitude, and the subscripts a, b, and c each represent one of the three-phase voltages.

[0046] In progress Figure 2 When calculating the amplitude, the formula can be used. The AC voltage amplitude of the grid-type wind turbine generator can be calculated using other amplitude calculation formulas, and this disclosure does not limit this.

[0047] In step S103, based on the reactive power command reference value, AC voltage amplitude, and rated AC voltage effective value of the grid-type wind turbine generator set, the effective value of the positive sequence internal potential of the grid-type wind turbine generator set is determined.

[0048] In an exemplary embodiment of this disclosure, when determining the effective value of the positive sequence internal potential of the grid-type wind turbine generator based on the reactive power command reference value, the AC voltage amplitude, and the effective value of the rated AC voltage of the grid-type wind turbine generator, as follows: Figure 2As shown, the effective value of the positive sequence internal potential of the grid-type wind turbine generator set can be calculated based on the AC voltage amplitude, the rated AC voltage effective value and voltage droop coefficient of the grid-type wind turbine generator set, the reactive power command reference value, and the theoretical value of the positive sequence reactive power of the grid-type wind turbine generator set.

[0049] In step S104, the positive sequence phase angle of the grid-connected wind turbine generator is obtained. For example, this can be achieved through... Figure 2 The calculation method in the figure is used to calculate the positive sequence phase angle θ of the grid-type wind turbine generator. + .

[0050] In step S105, based on the effective value of the positive sequence internal potential and the positive sequence phase angle of the grid-type wind turbine generator set, the positive sequence internal potential of the grid-type wind turbine generator set is calculated, such as... Figure 2 As shown.

[0051] In an exemplary embodiment of this disclosure, when calculating the positive-sequence internal potential of the grid-connected wind turbine generator based on the effective value of the positive-sequence internal potential and the positive-sequence phase angle, it can be based on the formula... Calculate the positive-sequence internal potential of the grid-connected wind turbine generator set. Here, e abc+ =[e a+ e b+ e c+ ] T This represents the positive-sequence internal potential. θ represents the effective value of the positive sequence potential. + The positive sequence phase angle is represented by T, which represents the transpose.

[0052] In step S106, the positive sequence internal potential is used as the modulation reference wave of the power module of the grid-type wind turbine generator set to control the grid-type wind turbine generator set.

[0053] In an exemplary embodiment of this disclosure, an insulated gate bipolar transistor (IGBT) pulse wave can be generated, for example, by using the positive sequence internal potential as a modulation reference wave for the power module of the grid-type wind turbine generator.

[0054] like Figure 2 As shown, in addition to controlling the modulation reference wave of the power module of the grid-type wind turbine generator set, other controls can also be performed, such as virtual control of the synchronous generator rotor motion equation and excitation simulation control of the synchronous generator.

[0055] In an exemplary embodiment of this disclosure, during the virtual control of the synchronous generator rotor motion equation, the positive sequence components of the three-phase current of the grid-connected wind turbine generator set can be obtained first. Based on the positive sequence internal potential effective value, positive sequence phase angle, and positive sequence components of the three-phase current of the grid-connected wind turbine generator set, the theoretical value of the positive sequence active power of the grid-connected wind turbine generator set is updated. Then, based on the updated theoretical value of the positive sequence active power of the grid-connected wind turbine generator set, the virtual control of the synchronous generator rotor motion equation of the grid-connected wind turbine generator set is performed.

[0056] In an exemplary embodiment of this disclosure, when updating the theoretical value of the positive-sequence active power of the grid-connected wind turbine based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase current of the grid-connected wind turbine, the formula can be used. Calculate the updated theoretical value of the positive-sequence active power of the grid-connected wind turbine generator set. Here, i a+ i b+ i c+ The positive sequence component of each phase current in the three-phase current is represented by T, which represents the transpose, and P is the positive sequence component of each phase current. + = <e abc+ i abc+ > represents the theoretical value of the positive-sequence active power. <e abc+ i abc+ > indicates e abc+ and i abc+ The inner product, e abc+ i represents the positive-sequence internal potential. abc+ θ represents the positive sequence component of the three-phase current. + This represents the positive sequence phase angle.

[0057] In an exemplary embodiment of this disclosure, during the excitation simulation control of the synchronous generator, the positive-sequence components of the three-phase current of the grid-type wind turbine generator set can be obtained first. Based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase current of the grid-type wind turbine generator set, the theoretical value of the positive-sequence reactive power of the grid-type wind turbine generator set is updated. Then, based on the updated theoretical value of the positive-sequence reactive power of the grid-type wind turbine generator set and the positive-sequence components of the three-phase voltage, the excitation simulation control of the synchronous generator of the grid-type wind turbine generator set is performed.

[0058] In an exemplary embodiment of this disclosure, when updating the theoretical value of the positive-sequence reactive power of the grid-connected wind turbine based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase current, the formula can be used. Calculate the updated theoretical value of the positive-sequence reactive power of the grid-connected wind turbine generator set. Here, Q += <e abc+⊥ i abc+ > represents the theoretical value of the positive-sequence reactive power. θ represents the effective value of the positive sequence potential. + i represents the positive sequence phase angle. a+ i b+ i c+ This represents the positive sequence component of each phase current in the three-phase current, where T represents the transpose, and i abc+ This represents the positive sequence component of the three-phase current. <e abc+⊥ i abc+ > indicates e abc+⊥ and i abc+ The inner product, e abc+⊥ This represents the orthogonal quantity that indicates a 90-degree phase shift in the positive sequence potential.

[0059] In progress Figure 2 During the core calculations, the following formulas can be used to calculate the positive-sequence internal potential, the updated theoretical value of positive-sequence active power, and the updated theoretical value of positive-sequence reactive power of the grid-type wind turbine generator set.

[0060]

[0061]

[0062]

[0063] The control method for grid-connected wind turbine generators according to exemplary embodiments of the present disclosure uses positive and negative sequence components extracted based on a Kalman filter to perform unbalanced control of the grid-connected wind turbines, which can avoid the secondary pulsation introduced by the negative sequence component causing system power oscillation under unbalanced voltage conditions.

[0064] Furthermore, according to exemplary embodiments of the present disclosure, a computer-readable storage medium is also provided, on which a computer program is stored, which, when executed, implements a control method for a grid-connected wind turbine generator according to exemplary embodiments of the present disclosure.

[0065] In an exemplary embodiment of this disclosure, the computer-readable storage medium may carry one or more programs that, when executed, perform the following steps: acquiring the positive-sequence components of the three-phase voltage of a grid-connected wind turbine generator set; calculating the AC voltage amplitude of the grid-connected wind turbine generator set based on the positive-sequence components of the three-phase voltage; determining the effective value of the positive-sequence internal potential of the grid-connected wind turbine generator set based on the reactive power command reference value, the AC voltage amplitude, and the effective value of the rated AC voltage of the grid-connected wind turbine generator set; acquiring the positive-sequence phase angle of the grid-connected wind turbine generator set; calculating the positive-sequence internal potential of the grid-connected wind turbine generator set based on the effective value of the positive-sequence internal potential and the positive-sequence phase angle; and using the positive-sequence internal potential as a modulation reference wave for the power module of the grid-connected wind turbine generator set to control the grid-connected wind turbine generator set.

[0066] Computer-readable storage media can be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In embodiments of this disclosure, a computer-readable storage medium can be any tangible medium that contains or stores a computer program that can be used by or in conjunction with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable storage medium can be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (radio frequency), etc., or any suitable combination thereof. A computer-readable storage medium can be included in any apparatus; it can also exist independently without being assembled into that apparatus.

[0067] Furthermore, according to exemplary embodiments of the present disclosure, a computer program product is also provided, wherein the instructions in the computer program product are executable by a processor of a computer device to perform a method for controlling a grid-connected wind turbine generator according to exemplary embodiments of the present disclosure.

[0068] The above has been combined Figure 1 and Figure 2 A control method for a grid-connected wind turbine generator according to exemplary embodiments of the present disclosure has been described. Hereinafter, reference will be made to... Figure 3 A control device and its units for a grid-type wind turbine generator set according to exemplary embodiments of the present disclosure will be described.

[0069] Figure 3A block diagram of a control device for a grid-connected wind turbine generator set according to an exemplary embodiment of the present disclosure is shown. Figure 4 A block diagram of a control device for a grid-connected wind turbine generator set according to another exemplary embodiment of the present disclosure is shown.

[0070] Reference Figure 3 The control device for a grid-type wind turbine generator set includes a positive sequence component acquisition unit 31, a voltage amplitude calculation unit 32, an internal potential effective value determination unit 33, a phase angle acquisition unit 34, an internal potential calculation unit 35, and a first control unit 36.

[0071] In an exemplary embodiment of this disclosure, the control device for the grid-type wind turbine generator set may be disposed in the converter of the grid-type wind turbine generator set.

[0072] The positive sequence component acquisition unit 31 is configured to acquire the positive sequence component of the three-phase voltage of the grid-connected wind turbine generator set.

[0073] In an exemplary embodiment of this disclosure, the positive sequence component acquisition unit 31 may be configured to acquire the positive sequence component of the three-phase voltage based on a Kalman filter.

[0074] The voltage amplitude calculation unit 32 is configured to calculate the AC voltage amplitude of the grid-type wind turbine generator based on the positive sequence component of the three-phase voltage.

[0075] The internal potential effective value determination unit 33 is configured to determine the positive sequence internal potential effective value of the grid-type wind turbine generator set based on the reactive power command reference value, AC voltage amplitude, and rated AC voltage effective value of the grid-type wind turbine generator set.

[0076] In an exemplary embodiment of this disclosure, the internal potential effective value determination unit 33 may be configured to: calculate the positive sequence internal potential effective value of the grid-type wind turbine generator based on the AC voltage amplitude, the rated AC voltage effective value voltage droop coefficient of the grid-type wind turbine generator, the reactive power command reference value, and the theoretical value of the positive sequence reactive power of the grid-type wind turbine generator.

[0077] Phase angle acquisition unit 34 is configured to acquire the positive sequence phase angle of the grid-type wind turbine generator set;

[0078] The internal potential calculation unit 35 is configured to calculate the positive sequence internal potential of the grid-type wind turbine generator set based on the effective value of the positive sequence internal potential and the positive sequence phase angle.

[0079] In an exemplary embodiment of this disclosure, the internal potential calculation unit 35 may be configured to: calculate based on the formula Calculate the positive-sequence internal potential of the grid-connected wind turbine generator set, where eabc+ =[e a+ e b+ e c+ ] T This represents the positive-sequence internal potential. θ represents the effective value of the positive sequence potential. + The positive sequence phase angle is represented by T, which represents the transpose.

[0080] The first control unit 36 ​​is configured to use the positive sequence internal potential as a modulation reference wave for the power module of the grid-type wind turbine generator set to control the grid-type wind turbine generator set.

[0081] In addition to the positive sequence component acquisition unit 31, voltage amplitude calculation unit 32, internal potential effective value determination unit 33, phase angle acquisition unit 34, internal potential calculation unit 35, and first control unit 36, the control device of the grid-connected wind turbine generator may also include a second control unit 37 and / or a third control unit 38. (Refer to...) Figure 4 In addition to the positive sequence component acquisition unit 31, voltage amplitude calculation unit 32, internal potential effective value determination unit 33, phase angle acquisition unit 34, internal potential calculation unit 35, and first control unit 36, the control device of the grid-type wind turbine generator also includes a second control unit 37 and a third control unit 38.

[0082] The second control unit 37 is configured to: acquire the positive-sequence components of the three-phase current of the grid-type wind turbine generator set; update the theoretical value of the positive-sequence active power of the grid-type wind turbine generator set based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase current of the grid-type wind turbine generator set; and perform virtual control of the synchronous generator rotor motion equation of the grid-type wind turbine generator set based on the updated theoretical value of the positive-sequence active power of the grid-type wind turbine generator set.

[0083] In an exemplary embodiment of this disclosure, the second control unit 37 may be configured to: based on the formula Calculate the updated theoretical value of the positive-sequence active power of the grid-connected wind turbine generator set, where i a+ i b+ i c+ The positive sequence component of each phase current in the three-phase current is represented by T, which represents the transpose, and P is the positive sequence component of each phase current. + = <e abc+ i abc+ > represents the theoretical value of the positive-sequence active power. <e abc+ i abc+ > indicates e abc+ and i abc+ The inner product, e abc+ i represents the positive-sequence internal potential.abc+ θ represents the positive sequence component of the three-phase current. + This represents the positive sequence phase angle.

[0084] The third control unit 38 is configured to: acquire the positive-sequence components of the three-phase current of the grid-type wind turbine generator set; update the theoretical value of the positive-sequence reactive power of the grid-type wind turbine generator set based on the effective value of the positive-sequence internal potential, the positive-sequence phase angle, and the positive-sequence components of the three-phase current of the grid-type wind turbine generator set; and perform excitation simulation control of the synchronous generator of the grid-type wind turbine generator set based on the updated theoretical value of the positive-sequence reactive power of the grid-type wind turbine generator set and the positive-sequence components of the three-phase voltage.

[0085] In an exemplary embodiment of this disclosure, the third control unit 38 may be configured to: based on the formula Calculate the theoretical value of the updated positive-sequence reactive power of the grid-connected wind turbine generator set, where Q + = <e abc+⊥ i abc+ > represents the theoretical value of the positive-sequence reactive power. θ represents the effective value of the positive sequence potential. + i represents the positive sequence phase angle. a+ i b+ i c+ This represents the positive sequence component of each phase current in the three-phase current, where T represents the transpose, and i abc+ This represents the positive sequence component of the three-phase current. <e abc+⊥ i abc+ > indicates e abc+⊥ and i abc+ The inner product, e abc+⊥ This represents the orthogonal quantity that indicates a 90-degree phase shift in the positive sequence potential.

[0086] Regarding the apparatus in the above embodiments, the specific manner in which each unit performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0087] The above has been combined Figures 3 to 4 A control device for a grid-connected wind turbine generator according to exemplary embodiments of the present disclosure has been described. Next, in conjunction with... Figure 5 A computing device according to exemplary embodiments of the present disclosure will be described.

[0088] Figure 5 A schematic diagram of a computing device according to an exemplary embodiment of the present disclosure is shown.

[0089] Reference Figure 5The computing device 5 according to an exemplary embodiment of the present disclosure includes a memory 51 and a processor 52. The memory 51 stores a computer program, which, when executed by the processor 52, implements a control method for a grid-type wind turbine generator according to an exemplary embodiment of the present disclosure.

[0090] In an exemplary embodiment of this disclosure, when the computer program is executed by the processor 52, the following steps can be implemented: acquiring the positive-sequence components of the three-phase voltage of the grid-connected wind turbine generator set; calculating the AC voltage amplitude of the grid-connected wind turbine generator set based on the positive-sequence components of the three-phase voltage; determining the effective value of the positive-sequence internal potential of the grid-connected wind turbine generator set based on the reactive power command reference value, the AC voltage amplitude, and the effective value of the rated AC voltage of the grid-connected wind turbine generator set; acquiring the positive-sequence phase angle of the grid-connected wind turbine generator set; calculating the positive-sequence internal potential of the grid-connected wind turbine generator set based on the effective value of the positive-sequence internal potential and the positive-sequence phase angle; and using the positive-sequence internal potential as a modulation reference wave for the power module of the grid-connected wind turbine generator set to control the grid-connected wind turbine generator set.

[0091] In an exemplary embodiment of this disclosure, the computing device may be disposed in the converter of the grid-type wind turbine generator set.

[0092] According to exemplary embodiments of the present disclosure, a grid-connected wind turbine generator set is provided. The grid-connected wind turbine generator set includes a control device for a grid-connected wind turbine generator set according to exemplary embodiments of the present disclosure, or a computing device according to exemplary embodiments of the present disclosure.

[0093] Figure 5 The computing device shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments disclosed herein.

[0094] The above has been referred to Figures 1 to 5 A control method and apparatus for a grid-connected wind turbine generator set according to exemplary embodiments of the present disclosure are described. However, it should be understood that: Figures 3 to 4 The control device and its units of the grid-connected wind turbine generator shown can be configured as software, hardware, firmware, or any combination thereof to perform specific functions. Figure 5 The computing device shown is not limited to the components shown above, but some components may be added or removed as needed, and the above components may also be combined.

[0095] According to the exemplary embodiments of the present disclosure, a control method and apparatus for a grid-type wind turbine generator set involves acquiring the positive-sequence components of the three-phase voltage of the grid-type wind turbine generator set, calculating the AC voltage amplitude of the grid-type wind turbine generator set based on the positive-sequence components of the three-phase voltage, determining the effective value of the positive-sequence internal potential of the grid-type wind turbine generator set based on the reactive power command reference value, AC voltage amplitude, and rated AC voltage effective value of the grid-type wind turbine generator set, acquiring the positive-sequence phase angle of the grid-type wind turbine generator set, calculating the positive-sequence internal potential of the grid-type wind turbine generator set based on the effective value of the positive-sequence internal potential and the positive-sequence phase angle, and using the positive-sequence internal potential as the modulation reference wave of the power module of the grid-type wind turbine generator set to control the grid-type wind turbine generator set. This control of the unbalanced voltage avoids system power oscillation caused by secondary pulsations introduced by the negative-sequence components under unbalanced voltage conditions.

[0096] Furthermore, according to the exemplary embodiments of the present disclosure, the control method and apparatus for a grid-type wind turbine generator set can first obtain the positive sequence components of the three-phase current of the grid-type wind turbine generator set, update the theoretical value of the positive sequence active power of the grid-type wind turbine generator set based on the effective value of the positive sequence internal potential, the positive sequence phase angle, and the positive sequence components of the three-phase current of the grid-type wind turbine generator set, and then perform virtual control of the synchronous generator rotor motion equation of the grid-type wind turbine generator set based on the updated theoretical value of the positive sequence active power of the grid-type wind turbine generator set.

[0097] Furthermore, according to the control method and apparatus for a grid-type wind turbine generator set according to the exemplary embodiments of this disclosure, the positive sequence components of the three-phase current of the grid-type wind turbine generator set can be obtained first. Based on the effective value of the positive sequence internal potential, the positive sequence phase angle, and the positive sequence components of the three-phase current of the grid-type wind turbine generator set, the theoretical value of the positive sequence reactive power of the grid-type wind turbine generator set is updated. Then, based on the updated theoretical value of the positive sequence reactive power of the grid-type wind turbine generator set and the positive sequence components of the three-phase voltage, the excitation simulation control of the synchronous generator of the grid-type wind turbine generator set is performed.

[0098] Although this disclosure has been specifically shown and described with reference to exemplary embodiments thereof, those skilled in the art should understand that various changes in form and detail may be made therein without departing from the spirit and scope of this disclosure as defined by the claims.

Claims

1. A control method for a grid-connected wind turbine generator set, characterized in that, include: Obtain the positive sequence components of the three-phase voltage of a grid-connected wind turbine generator set; The AC voltage amplitude of the grid-type wind turbine generator set is calculated based on the positive sequence components of the three-phase voltage. Based on the reactive power command reference value, AC voltage amplitude, and rated AC voltage effective value of the grid-type wind turbine generator set, the positive sequence internal potential effective value of the grid-type wind turbine generator set is determined. Obtain the positive sequence phase angle of the grid-connected wind turbine generator set; The positive sequence internal potential of the grid-type wind turbine generator set is calculated based on the effective value of the positive sequence internal potential and the positive sequence phase angle. The positive sequence internal potential is used as the modulation reference wave of the power module of the grid-type wind turbine generator set to control the grid-type wind turbine generator set.

2. The control method according to claim 1, characterized in that, The control method further includes: Obtain the positive sequence components of the three-phase current of the grid-connected wind turbine generator set; Based on the positive-sequence internal potential RMS value, positive-sequence phase angle, and positive-sequence components of the three-phase current of the grid-type wind turbine generator set, update the theoretical value of the positive-sequence active power of the grid-type wind turbine generator set. Virtual control of the synchronous generator rotor motion equation of the grid-type wind turbine is performed based on the updated theoretical value of the positive sequence active power of the grid-type wind turbine.

3. The control method according to claim 1, characterized in that, The control method further includes: Obtain the positive sequence components of the three-phase current of the grid-connected wind turbine generator set; Based on the positive sequence internal potential RMS value, positive sequence phase angle, and positive sequence components of the three-phase current of the grid-type wind turbine generator set, update the theoretical value of the positive sequence reactive power of the grid-type wind turbine generator set. The excitation simulation control of the synchronous generator of the grid-type wind turbine is performed based on the updated theoretical value of the positive sequence reactive power and the positive sequence component of the three-phase voltage.

4. The control method according to claim 1, characterized in that, Based on the effective value of the positive sequence internal potential and the positive sequence phase angle of the grid-type wind turbine generator set, the positive sequence internal potential of the grid-type wind turbine generator set is calculated, including: Based on formula Calculate the positive sequence internal potential of the grid-type wind turbine generator set. Among them, e abc+ =[e a+ e b+ e c+ ] T This represents the positive-sequence internal potential. θ represents the effective value of the positive sequence potential. + The positive sequence phase angle is represented by T, which represents the transpose.

5. The control method according to claim 2, characterized in that, Based on the positive-sequence internal potential RMS value, positive-sequence phase angle, and positive-sequence components of the three-phase current of the grid-connected wind turbine generator set, the theoretical value of the positive-sequence active power of the grid-connected wind turbine generator set is updated, including: Based on formula Calculate the theoretical value of the updated positive-sequence active power of the grid-connected wind turbine generator set. Among them, i a+ i b+ i c+ The positive sequence component of each phase current in the three-phase current is represented by T, which represents the transpose, and P is the positive sequence component of each phase current. + = <e abc+ i abc+ > represents the theoretical value of the positive-sequence active power. <e abc+ i abc+ > indicates e abc+ and i abc+ The inner product, e abc+ i represents the positive-sequence internal potential. abc+ θ represents the positive sequence component of the three-phase current. + This represents the positive sequence phase angle.

6. The control method according to claim 3, characterized in that, Based on the positive-sequence internal potential RMS value, positive-sequence phase angle, and positive-sequence components of the three-phase current of the grid-connected wind turbine generator set, the theoretical value of the positive-sequence reactive power of the grid-connected wind turbine generator set is updated, including: Based on formula Calculate the theoretical value of the updated positive-sequence reactive power of the grid-connected wind turbine generator set. Among them, Q + = <e abc+⊥ i abc+ > represents the theoretical value of the positive-sequence reactive power. θ represents the effective value of the positive sequence potential. + i represents the positive sequence phase angle. a+ i b+ i c+ This represents the positive sequence component of each phase current in the three-phase current, where T represents the transpose, and i abc+ This represents the positive sequence component of the three-phase current. <e abc+⊥ i abc+ > indicates e abc+⊥ and i abc+ The inner product, e abc+⊥ This represents the orthogonal quantity that indicates a 90-degree phase shift in the positive sequence potential.

7. The control method according to claim 1, characterized in that, Obtain the positive-sequence components of the three-phase voltage of a grid-connected wind turbine generator set, including: The positive sequence components of the three-phase voltages are obtained based on a Kalman filter.

8. The control method according to claim 1, characterized in that, Based on the reactive power command reference value, AC voltage amplitude, and rated AC voltage RMS value of the grid-connected wind turbine generator set, the positive sequence internal potential RMS value of the grid-connected wind turbine generator set is determined, including: Based on the AC voltage amplitude, rated AC voltage RMS value, voltage droop coefficient, reactive power command reference value, and theoretical value of positive sequence reactive power of the grid-type wind turbine generator set, the RMS value of the positive sequence internal potential of the grid-type wind turbine generator set is calculated.

9. A control device for a grid-connected wind turbine generator set, characterized in that, include: The positive sequence component acquisition unit is configured to acquire the positive sequence components of the three-phase voltage of the grid-connected wind turbine generator set; The voltage amplitude calculation unit is configured to calculate the AC voltage amplitude of the grid-type wind turbine generator based on the positive sequence component of the three-phase voltage; The internal potential effective value determination unit is configured to determine the positive sequence internal potential effective value of the grid-type wind turbine generator set based on the reactive power command reference value, AC voltage amplitude, and rated AC voltage effective value of the grid-type wind turbine generator set. The phase angle acquisition unit is configured to acquire the positive sequence phase angle of the grid-type wind turbine generator set; The internal potential calculation unit is configured to calculate the positive sequence internal potential of the grid-type wind turbine generator set based on the effective value of the positive sequence internal potential and the positive sequence phase angle. and The first control unit is configured to use the positive sequence internal potential as a modulation reference wave for the power module of the grid-type wind turbine generator set to control the grid-type wind turbine generator set.

10. The control device according to claim 9, characterized in that, The control device is located in the converter of the grid-type wind turbine generator set.

11. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the control method for the grid-type wind turbine generator set as described in any one of claims 1 to 8.

12. A computing device, characterized in that, include: processor; A memory storing a computer program, which, when executed by the processor, implements the control method for a grid-connected wind turbine generator set as described in any one of claims 1 to 8.

13. The computing device according to claim 12, characterized in that, The computing device is located in the converter of the grid-type wind turbine generator set.

14. A grid-connected wind turbine generator set, characterized in that, It includes the control device for a grid-type wind turbine generator as described in claim 9 or 10, or the computing device as described in claim 12 or 13.

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