New energy power generation cluster and oscillation suppression method and device thereof

Abstract

The invention provides a new energy power generation cluster and an oscillation suppression method and device thereof. The oscillation suppression method comprises the steps of determining whether an overall oscillation condition at a power transmission convergence position meets a preset oscillation condition or not based on an electrical quantity at the power transmission convergence position of the new energy power generation cluster; in response to the condition that the preset oscillation condition is met, determining an active power compensation value of each new energy generator set based on an equivalent electrical distance from each new energy generator set in the new energy power generation cluster to the power transmission convergence and a current active power value; distributing respective active power compensation values to the new energy generator sets to control the new energy generator sets to realize optimal damping compensation of single-machine active power output; wherein the power transmission gathering position is connected to the alternating current side of a nearby flexible direct current sending-out device, and the direct current side of the flexible direct current sending-out device is used for sending out flexible direct current.

Description

Technical Field

[0001] The present disclosure generally relates to the field of renewable energy power generation technology, and more specifically, to a renewable energy power generation cluster and an oscillation suppression method and device thereof. Background Art

[0002] The large-scale access of power electronic equipment and new energy has led to significant changes in the structure and dynamic characteristics of the power grid, and the broadband oscillation problem caused by the interaction between power electronic equipment and the power grid has become increasingly prominent. At the same time, the large-scale commissioning of DC projects has also produced a typical operating scenario of large-capacity transmission of new energy via DC. In particular, in the scenario of large-scale transmission of new energy via flexible DC, the broadband oscillation problem of the system caused by the coupling of DC transmission technology and new energy power electronics technology cannot be ignored.

[0003] Existing broadband oscillation suppression methods can be divided into source-side suppression and grid-side suppression from the perspective of the control object. The strategy of source-side suppression can be designed mainly according to the control strategy, which is divided into: adjusting controller parameters and controller structure, additional damping control and control branch compensation; while the suppression strategy on the grid side is mainly implemented by two means: FACTS (Flexible Alternative Current Transmission Systems) and additional control of DC transmission. The FACTS device can quickly adjust the system flow at the power frequency and inject reverse oscillating current into the system to improve the transmission capacity and stability of the system. It can adapt to the oscillation problem of the system under different working conditions. It has flexible control and obvious suppression effect.

[0004] As for the grid-side suppression method, it mainly acts on lines that are prone to resonance and transmission lines that may cause broadband oscillations. By eliminating the resonance conditions or increasing the damping, the lines and nearby equipment that are prone to oscillations are protected. Comprehensive analysis of the suppression methods on the grid and source sides shows that source-side suppression can achieve active suppression from the source of oscillations, directly extract the electrical quantities related to oscillations, and damp the generation mechanism nearby to achieve a stronger damping effect. Grid-side suppression supports the bus voltage through reactive power adjustment, and achieves oscillation suppression by adjusting the bus voltage.

[0005] As the current system oscillation problem gradually presents a regional oscillation form of multiple machines and multiple networks, relying solely on the current independent suppression methods on the network side and the source side cannot effectively solve the system oscillation problem, and the oscillation suppression effect needs to be further improved. Summary of the invention

[0006] An exemplary embodiment of the present disclosure is to provide a new energy power generation cluster and an oscillation suppression method and device thereof, which can solve the current problems of insufficient coordination of oscillation suppression on the source and grid sides and non-optimal oscillation suppression of the regional system.

[0007] According to a first aspect of an embodiment of the present disclosure, there is provided an oscillation suppression method for a new energy power generation cluster, the oscillation suppression method comprising: determining whether the overall oscillation situation at the transmission collection point of the new energy power generation cluster meets a preset oscillation condition based on the electrical quantity at the transmission collection point of the new energy power generation cluster; in response to meeting the preset oscillation condition, determining the active power compensation value of each new energy power generation group in the new energy power generation cluster based on the equivalent electrical distance from the transmission collection point and the current active power value; distributing the respective active power compensation values ​​to each new energy power generation group to control each new energy power generation group to achieve the optimal damping compensation of the single-machine active power output; wherein the transmission collection point is connected to the AC side of a nearby flexible DC transmission device, and the DC side of the flexible DC transmission device is used to transmit flexible DC power.

[0008] Optionally, the active power compensation value of each new energy generator set is used to input into the damping compensation unit of the new energy generator set to obtain an additional active power control signal that needs to be added to the current control loop of the new energy generator set.

[0009] Optionally, the step of determining the active power compensation value of each new energy generator set based on the equivalent electrical distance between each new energy generator set and the power transmission collection point and the current active power value includes: determining the active power compensation value of each new energy generator set based on the equivalent electrical distance between each new energy generator set and the power transmission collection point and the current active power value through the compensation power target function; wherein the active power compensation value of each new energy generator set is the optimal solution for making the compensation power target function obtain the maximum value; wherein the compensation power target function is a function of weighted summation of the integral results corresponding to each new energy generator set, and the integral result corresponding to each new energy generator set is: obtained by time integrating the absolute value of the difference between the quantity to be solved of the new energy generator set and the current active power value, and the weight of the integral result corresponding to each new energy generator set is determined based on the equivalent electrical distance of the new energy generator set from the power transmission collection point.

[0010] Optionally, the shorter the equivalent electrical distance between the new energy generator set and the power transmission collector, the greater the weight of the integral result corresponding to the new energy generator set.

[0011] Optionally, the constraints of the compensation power objective function are: the quantity to be solved for each new energy generator set is greater than or equal to a first preset threshold corresponding to the new energy generator set, and is less than or equal to a second preset threshold corresponding to the new energy generator set; wherein the first preset threshold is determined based on the standby capacity of the new energy generator set, and the second preset threshold is determined based on the active output upper limit of the new energy generator set.

[0012] Optionally, the power transmission collection point includes a collection bus of the new energy power generation cluster or a transmission line after the convergence of the new energy power generation cluster.

[0013] Optionally, the step of determining whether the overall oscillation condition of the new energy power generation cluster meets the preset oscillation condition based on the electrical quantity at the transmission collection point where the new energy power generation cluster transmits electricity to the power grid includes: determining whether the oscillation amplitude and oscillation frequency of the active power value at the transmission collection point meet the preset wide-band oscillation condition.

[0014] According to a second aspect of an embodiment of the present disclosure, an oscillation suppression device for a new energy power generation cluster is provided, comprising: an electrical quantity monitoring module, a processor, and a communication module; the electrical quantity monitoring module is used to monitor the electrical quantity at the transmission collection point of the new energy power generation cluster; the processor is configured to perform the following processing: based on the electrical quantity at the transmission collection point of the new energy power generation cluster, determine whether the overall oscillation situation at the transmission collection point meets the preset oscillation condition; in response to meeting the preset oscillation condition, determine the active power compensation value of each new energy generator set in the new energy power generation cluster based on the equivalent electrical distance of each new energy generator set from the transmission collection point and the current active power value; control the communication module to distribute the respective active power compensation values ​​to each new energy generator set, so as to control each new energy generator set to achieve the optimal damping compensation of the single-machine active power output; wherein the transmission collection point is connected to the AC side of a nearby flexible DC transmission device, and the DC side of the flexible DC transmission device is used to transmit flexible DC power.

[0015] Optionally, the electrical quantity monitoring module is connected to the power transmission collection point.

[0016] Optionally, the active power compensation value of each new energy generator set is used to input into the damping compensation unit of the new energy generator set to obtain an additional active power control signal that needs to be added to the current control loop of the new energy generator set.

[0017] Optionally, the process of determining the active power compensation value of each new energy generator set based on the equivalent electrical distance of each new energy generator set from the transmission collection point and the current active power value includes: determining the active power compensation value of each new energy generator set based on the equivalent electrical distance of each new energy generator set from the transmission collection point and the current active power value through the compensation power target function; wherein the active power compensation value of each new energy generator set is the optimal solution for making the compensation power target function obtain the maximum value; wherein the compensation power target function is a function of weighted summation of the integral results corresponding to each new energy generator set, and the integral result corresponding to each new energy generator set is: obtained by time integrating the absolute value of the difference between the quantity to be solved of the new energy generator set and the current active power value, and the weight of the integral result corresponding to each new energy generator set is determined based on the equivalent electrical distance of the new energy generator set from the transmission collection point.

[0018] Optionally, the shorter the equivalent electrical distance between the new energy generator set and the power transmission collector, the greater the weight of the integral result corresponding to the new energy generator set.

[0019] Optionally, the constraints of the compensation power objective function are: the quantity to be solved for each new energy generator set is greater than or equal to a first preset threshold corresponding to the new energy generator set, and is less than or equal to a second preset threshold corresponding to the new energy generator set; wherein the first preset threshold is determined based on the standby capacity of the new energy generator set, and the second preset threshold is determined based on the active output upper limit of the new energy generator set.

[0020] Optionally, the power transmission collection point includes a collection bus of the new energy power generation cluster or a transmission line after the convergence of the new energy power generation cluster.

[0021] Optionally, the processing of determining whether the overall oscillation situation of the new energy power generation cluster meets the preset oscillation conditions based on the electrical quantity at the transmission collection point where the new energy power generation cluster transmits electricity to the power grid includes: determining whether the oscillation amplitude and oscillation frequency of the active power value at the transmission collection point meet the preset wide-band oscillation conditions.

[0022] According to a third aspect of an embodiment of the present disclosure, there is provided a new energy power generation cluster, comprising: a plurality of new energy power generation groups and the oscillation suppression device as described above.

[0023] According to the exemplary embodiments of the present invention, a new energy power generation cluster and its oscillation suppression method and device are proposed to identify the overall regional oscillation and uniformly distribute and manage the oscillation suppression active power flow of each unit in the source-side power generation cluster, so as to achieve optimal regional oscillation damping suppression, solve the current difficulties of insufficient coordination on the source-grid side and non-optimal regional system oscillation suppression, and solve and apply to the problem of insufficient broadband oscillation efficiency in typical power generation and transmission scenarios of new power systems.

[0024] Additional aspects and / or advantages of the present general inventive concept will be set forth in part in the following description and in part will be apparent from the description or may be learned through practice of the present general inventive concept. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and other objects and features of the exemplary embodiments of the present disclosure will become more apparent through the following description in conjunction with the accompanying drawings which exemplarily illustrate the embodiments, in which:

[0026] Figure 1 A flow chart showing an oscillation suppression method for a new energy power generation cluster according to an exemplary embodiment of the present disclosure;

[0027] Figure 2 The system access topology of the oscillation suppression device of the new energy power generation cluster according to the exemplary embodiment of the present disclosure is shown;

[0028] Figure 3 A schematic diagram of current control of a direct-drive wind turbine with additional power damping compensation according to an exemplary embodiment of the present disclosure is shown;

[0029] Figure 4 A structural block diagram of an oscillation suppression device for a new energy power generation cluster according to an exemplary embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0030] Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like parts throughout. The embodiments will be described below with reference to the drawings in order to explain the present disclosure.

[0031] It should be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0032] It should be noted that the phrase "at least one of the items" in the present disclosure includes three types of parallel situations: "any one of the items", "a combination of any number of the items", and "all of the items". For example, "including at least one of A and B" includes the following three parallel situations: (1) including A; (2) including B; (3) including A and B. Another example is "executing at least one of step 1 and step 2" which means the following three parallel situations: (1) executing step 1; (2) executing step 2; (3) executing step 1 and step 2.

[0033] The present disclosure takes into account that the current grid-side suppression relies on the built control equipment and fails to achieve oscillation suppression from the source, while the source-side suppression is more dependent on the nearby and local oscillating electrical quantities of the power source, and fails to accurately perceive the overall oscillation damping suppression needs of the network, and the source network has not formed an effective overall optimal suppression method. As the current broadband oscillation problem gradually presents a regionalized oscillation form of multiple machines and multiple networks, relying solely on the current independent suppression methods on the grid side and the source side will have limited vision for solving the problem locally. For networking forms such as large generator clusters and distributed power generation bases, there is still a low degree of coordination between the grid side and the source side, and the oscillation suppression effect is not optimal.

[0034] Therefore, the present disclosure provides an oscillation suppression method applied to the power collection end near the flexible direct current sending end, adopts regional overall oscillation identification, and optimizes the control of each unit based on the power flow optimization allocation method of active power suppression, globally solves the oscillation problem of the multi-machine system, and realizes the unified allocation and management of the active power flow for oscillation suppression of each unit in the source-side power generation cluster, solves the optimal problem of oscillation suppression in the near area of ​​each unit, solves the current difficulties of insufficient coordination on the source and grid side and non-optimal oscillation suppression of the regional system, and solves and is applicable to the problem of insufficient broadband oscillation efficiency in typical power generation and transmission scenarios of new power systems.

[0035] Figure 1 A flowchart of an oscillation suppression method for a new energy power generation cluster according to an exemplary embodiment of the present disclosure is shown. As an example, the oscillation suppression method for a new energy power generation cluster according to an exemplary embodiment of the present disclosure may be Figure 2 The oscillation suppression device of the renewable energy power generation cluster shown is executed, or may be executed by a controller of the renewable energy power generation cluster.

[0036] Reference Figure 1 In step S101, the electrical quantity at the transmission collection point of the new energy power generation cluster is monitored.

[0037] The transmission collection point of the new energy power generation cluster is connected to the AC side of the nearby flexible DC transmission device, and the DC side of the flexible DC transmission device is used to transmit flexible DC power. In other words, the AC power output by each new energy generator set in the new energy power generation cluster is collected at the transmission collection point and transmitted to the flexible DC transmission end, so that the flexible DC transmission end converts the AC power into DC power and transmits it to the DC receiving end.

[0038] The transmission gathering point of a renewable energy power generation cluster is the power output gathering point of the renewable energy power generation cluster. As an example, the transmission gathering point of a renewable energy power generation cluster may include but is not limited to: the gathering bus of the renewable energy power generation cluster or the transmission line after the convergence of the renewable energy power generation cluster.

[0039] As an example, the flexible DC transmission device may be a converter of a flexible DC transmission end system.

[0040] As an example, the types of electrical quantities monitored at the transmission sink may include, but are not limited to: active power value and / or voltage value.

[0041] As an example, the types of new energy power generation groups within the new energy power generation cluster may include, but are not limited to: photovoltaic power generation groups and / or wind power generation groups.

[0042] As an example, the type of new energy power generation cluster may include but is not limited to at least one of the following types: a large-scale power generation cluster, a site-based power generation cluster, and a distributed power generation cluster.

[0043] In step S102, based on the electrical quantity at the power transmission collection point of the new energy power generation cluster, it is determined whether the overall oscillation situation at the power transmission collection point meets the preset oscillation condition.

[0044] As an example, the overall oscillation condition may include, but is not limited to: oscillation amplitude and / or oscillation frequency.

[0045] As an example, the preset oscillation condition may include, but is not limited to: a preset broadband oscillation condition.

[0046] As an example, step S102 may include: determining whether the oscillation amplitude and oscillation frequency of the active power value at the power transmission sink meet a preset wide-band oscillation condition.

[0047] According to an exemplary embodiment of the present disclosure, the overall oscillation damping suppression requirements in the vicinity of the flexible direct current sending end can be identified.

[0048] In step S103, in response to satisfying the preset oscillation condition, the active power compensation value of each new energy generator set in the new energy power generation cluster is determined based on the equivalent electrical distance between each new energy generator set and the transmission collection point and the current active power value.

[0049] Here, the determined single-machine active power compensation value is used for single-machine suppression of system oscillation and system damping compensation.

[0050] As an example, the active power compensation value of each renewable energy generator set can be determined based on the equivalent electrical distance of each renewable energy generator set from the power transmission collection point and the current active power value through the compensation power objective function. The active power compensation value of each renewable energy generator set is the optimal solution that maximizes the compensation power objective function.

[0051] As an example, the compensation power objective function is a function of weighted summation of the integral results corresponding to each new energy generator set, and the integral result corresponding to each new energy generator set is obtained by time integration of the absolute value of the difference between the quantity to be solved and the current active power value of the new energy generator set. Here, the quantity to be solved is the variable of active power compensation.

[0052] As an example, the weight of the integral result corresponding to each new energy generator set is determined based on the equivalent electrical distance between the new energy generator set and the power transmission collection point. For example, the shorter the equivalent electrical distance between the new energy generator set and the power transmission collection point (that is, the electrical quantity monitoring point), the greater the weight of the integral result corresponding to the new energy generator set.

[0053] As an example, the compensation power objective function can be shown as formula (1):

[0054]

[0055] Among them, P n (t(n=1,2,3…n) is the active power compensation value of the nth new energy generator set in the new energy power generation cluster, P n (0 is the current active power value of the nth new energy generator set (that is, the initial value when the oscillation occurs), K n is the power compensation weight of the nth renewable energy generator set. Its setting takes into account that the renewable energy generator set with a relatively close electrical distance to the transmission collection point plays a leading role in suppressing the oscillation near the flexible direct current sending end. A is a constant, and L n is the equivalent electrical distance between the nth renewable energy generator set and the power transmission collection point. It should be understood that the upper limit of the integral interval may also be other time lengths set according to actual conditions and specific needs, and the present disclosure does not limit this.

[0056] As an example, the constraint condition of the compensation power objective function may be: the quantity to be solved for each new energy generator set is greater than or equal to the first preset threshold corresponding to the new energy generator set, and is less than or equal to the second preset threshold corresponding to the new energy generator set. For example, the first preset threshold corresponding to the new energy generator set is determined based on the spare capacity of the new energy generator set, and the second preset threshold corresponding to the new energy generator set is determined based on the upper limit of the active output of the new energy generator set. According to this embodiment, the active power constraint is introduced by considering the spare capacity and the upper limit of the active output of each new energy generator set.

[0057] Since the objective function has an absolute value, it is a nonlinear programming problem. We can use absolute value programming technology to introduce non-negative auxiliary variables, and then use linear programming optimization tools or improved algorithms to solve P. n (t). The present disclosure does not limit the specific solution method.

[0058] In step S104, each new energy generating set is distributed with its own active power compensation value, so as to control each new energy generating set to achieve the optimal damping compensation of the single-machine active power output.

[0059] As an example, an active power flow control instruction may be generated based on the active power compensation value of the new energy generator set, and the active power flow control instruction may be sent to the controller of the new energy generator set.

[0060] As an example, the active power compensation value of each new energy generator set is used to input the damping compensation unit of the new energy generator set to obtain the additional active power control signal that needs to be added to the current control loop of the new energy generator set. In other words, each new energy generator set inputs the received active power compensation value into the damping compensation unit to generate an additional active power control signal, and adds the additional active power control signal to its current control loop, so that the active power injected into the system by the new energy generator set has a positive damping characteristic, and realizes the optimal damping compensation of the active power output of a single machine.

[0061] As an example, the damping compensation unit may include but is not limited to the following links: a filtering link, a gain link, a phase shift link, and a limiting link.

[0062] Figure 3 A schematic diagram of current control of a direct-drive wind turbine with additional power damping compensation according to an exemplary embodiment of the present disclosure is shown.

[0063] The grid-side converter of the PMSG direct-drive wind turbine adopts the idea of ​​voltage decoupling vector control, in which the controller adopts a dual closed-loop control strategy to achieve decoupling control of the output power by adjusting the current in the dq rotating coordinate system. At the same time, the control loop can stably control the DC bus voltage, and then form the trigger switching pulse of the grid-side converter through PWM modulation to achieve active and reactive power control of the converter grid-connected point.

[0064] In the dq coordinate system, the converter voltage outer loop controller adopts proportional integral control. The mathematical expression of the controller is shown in Equation 2, where i d_ref 、i q_ref is the inner loop current component; P ref is the given active power; Q s_ref is the reactive power of the given grid-connected point; P s is the measured active power at the grid connection point; Q s is the measured reactive power at the grid connection point; K p , K I are the proportional and integral coefficients of the outer loop controller respectively.

[0065]

[0066] In the dq coordinate system, the grid-side converter current inner loop controller also adopts proportional integral control, and the mathematical expression is shown in Equation 3, where U sd , U sq is the grid side voltage in the dq coordinate system; ω s is the grid angular frequency; R and L are the equivalent resistance and reactance of the wind turbine grid side; i d 、i q is the grid-side current in the dq coordinate system; K p , K I are the proportional coefficient and integral coefficient of the inner loop controller respectively.

[0067]

[0068] Based on the above controller mathematical expression, the typical control block diagram of PMSG wind turbine grid-side converter can be obtained as follows: Figure 3 shown.

[0069] Figure 2 A system access topology of an oscillation suppression device for a new energy power generation cluster according to an exemplary embodiment of the present disclosure is shown.

[0070] Reference Figure 2 According to the exemplary embodiment of the present invention, the oscillation suppression device of the renewable energy power generation cluster can be connected to the collecting bus or the sending end feeder side of the collecting bus of the large-scale power generation cluster, can be connected to the collecting bus or the sending end feeder side of the collecting bus of the renewable energy power generation station, and can be connected to the sending line after the convergence of the distributed power generation cluster.

[0071] Figure 4 A structural block diagram of an oscillation suppression device for a new energy power generation cluster according to an exemplary embodiment of the present disclosure is shown.

[0072] like Figure 4 As shown, the oscillation suppression device of a new energy power generation cluster according to an exemplary embodiment of the present disclosure includes: an electrical quantity monitoring module 10 , a processor 20 and a communication module 30 .

[0073] Specifically, the electrical quantity monitoring module 10 is used to monitor the electrical quantity at the power transmission collection point of the new energy power generation cluster.

[0074] The transmission junction is connected to the AC side of a nearby flexible DC transmission device, and the DC side of the flexible DC transmission device is used to transmit flexible DC power.

[0075] As an example, the power transmission collection point may include a collection bus of a renewable energy power generation cluster or a transmission line after the convergence of the renewable energy power generation cluster.

[0076] As an example, the electrical quantity monitoring module 10 may be connected to a power transmission collection point.

[0077] The processor 20 is configured to perform the following processing: based on the electrical quantity at the transmission collection point of the new energy power generation cluster, determine whether the overall oscillation situation at the transmission collection point meets the preset oscillation condition; in response to meeting the preset oscillation condition, determine the active power compensation value of each new energy power generation group based on the equivalent electrical distance of each new energy power generation group in the new energy power generation cluster from the transmission collection point and the current active power value; control the communication module 30 to distribute the respective active power compensation values ​​to each new energy power generation group, so as to control each new energy power generation group to achieve the optimal damping compensation of the single-machine active power output.

[0078] As an example, the active power compensation value of each new energy generator set is used to input the damping compensation unit of the new energy generator set to obtain an additional active power control signal that needs to be added to the current control loop of the new energy generator set.

[0079] As an example, the process of determining the active power compensation value of each new energy generator set based on the equivalent electrical distance of each new energy generator set from the transmission collection point and the current active power value may include: determining the active power compensation value of each new energy generator set based on the equivalent electrical distance of each new energy generator set from the transmission collection point and the current active power value through the compensation power objective function; wherein the active power compensation value of each new energy generator set is the optimal solution for maximizing the compensation power objective function.

[0080] The compensation power objective function is a function that performs weighted summation of the integral results corresponding to each new energy generator set. The integral result corresponding to each new energy generator set is obtained by time integrating the absolute value of the difference between the quantity to be solved and the current active power value of the new energy generator set. The weight of the integral result corresponding to each new energy generator set is determined based on the equivalent electrical distance between the new energy generator set and the transmission collection point.

[0081] As an example, the shorter the equivalent electrical distance between the new energy generator set and the power transmission collection point, the greater the weight of the integral result corresponding to the new energy generator set.

[0082] As an example, the constraints of the compensation power objective function may be: the quantity to be solved for each new energy generator set is greater than or equal to the first preset threshold corresponding to the new energy generator set, and is less than or equal to the second preset threshold corresponding to the new energy generator set; for example, the first preset threshold is determined based on the standby capacity of the new energy generator set, and the second preset threshold is determined based on the active output upper limit of the new energy generator set.

[0083] As an example, based on the electrical quantity at the transmission junction where the new energy power generation cluster transmits electricity to the power grid, the process of determining whether the overall oscillation condition of the new energy power generation cluster meets the preset oscillation conditions may include: determining whether the oscillation amplitude and oscillation frequency of the active power value at the transmission junction meet the preset wide-band oscillation conditions.

[0084] It should be understood that the specific processing performed by the oscillation suppression device of the new energy power generation cluster according to the exemplary embodiment of the present disclosure has been referred to. Figures 1 to 3 The details have been described in detail and will not be repeated here.

[0085] An exemplary embodiment of the present disclosure provides a new energy power generation cluster, comprising: a plurality of new energy power generation groups and an oscillation suppression device as described in the above exemplary embodiment.

[0086] An exemplary embodiment of the present disclosure provides a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to execute the oscillation suppression method of a new energy power generation cluster as described in the above exemplary embodiment. The computer-readable storage medium is any data storage device that can store data read by a computer system. Examples of computer-readable storage media include: read-only memory, random access memory, read-only optical disk, magnetic tape, floppy disk, optical data storage device, and carrier wave (such as data transmission through the Internet via a wired or wireless transmission path).

[0087] An electronic device according to an exemplary embodiment of the present disclosure includes: a processor (not shown) and a memory (not shown), wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor is prompted to execute the oscillation suppression method of the new energy power generation cluster as described in the above exemplary embodiment. As an example, the electronic device may be a controller of the new energy power generation cluster.

[0088] Although some exemplary embodiments of the present disclosure have been shown and described, it will be appreciated by those skilled in the art that modifications may be made to these embodiments without departing from the principles and spirit of the present disclosure, the scope of which is defined by the claims and their equivalents.

Claims

1. A method for suppressing oscillation of a new energy power generation cluster, characterized in that: The oscillation suppression method comprises: Based on the electrical quantity at the power transmission collection point of the new energy power generation cluster, determining whether the overall oscillation condition at the power transmission collection point meets the preset oscillation condition; In response to satisfying the preset oscillation condition, determining the active power compensation value of each new energy generator set in the new energy power generation cluster based on the equivalent electrical distance between each new energy generator set and the power transmission collection point and the current active power value; Distributing respective active power compensation values ​​to each of the new energy generating sets to control each of the new energy generating sets to achieve optimal damping compensation for the active power output of a single machine; The power transmission junction is connected to the AC side of a nearby flexible DC transmission device, and the DC side of the flexible DC transmission device is used to transmit flexible DC power.

2. The oscillation suppression method according to claim 1, characterized in that: The active power compensation value of each new energy generator set is used to input the damping compensation unit of the new energy generator set to obtain an additional active power control signal that needs to be added to the current control loop of the new energy generator set.

3. The oscillation suppression method according to claim 1, characterized in that: The step of determining the active power compensation value of each of the new energy generator sets based on the equivalent electrical distance between each of the new energy generator sets and the power transmission collection point and the current active power value comprises: Determine the active power compensation value of each of the new energy generator sets through the compensation power objective function based on the equivalent electrical distance between each of the new energy generator sets and the power transmission collection point and the current active power value; The active power compensation value of each new energy generator set is the optimal solution that maximizes the compensation power objective function; Among them, the compensation power objective function is a function of weighted summation of the integral results corresponding to the each new energy generator set, and the integral result corresponding to each new energy generator set is: obtained by time integration of the absolute value of the difference between the quantity to be solved and the current active power value of the new energy generator set, and the weight of the integral result corresponding to each new energy generator set is determined based on the equivalent electrical distance of the new energy generator set from the transmission collection point.

4. The oscillation suppression method according to claim 3, characterized in that: The shorter the equivalent electrical distance between the new energy generator set and the power transmission collector, the greater the weight of the integral result corresponding to the new energy generator set.

5. The oscillation suppression method according to claim 3, characterized in that: The constraint condition of the compensation power objective function is: the amount to be solved for each new energy generator set is greater than or equal to the first preset threshold corresponding to the new energy generator set, and is less than or equal to the second preset threshold corresponding to the new energy generator set; The first preset threshold is determined based on the spare capacity of the new energy generator set, and the second preset threshold is determined based on the active output upper limit of the new energy generator set.

6. The oscillation suppression method according to claim 1, characterized in that: The power transmission collection point includes the collection bus of the new energy power generation cluster or the transmission line after the new energy power generation cluster converges.

7. The oscillation suppression method according to claim 1, characterized in that: The step of determining whether the overall oscillation condition of the new energy power generation cluster meets the preset oscillation condition based on the electrical quantity at the power transmission collection point where the new energy power generation cluster transmits power to the power grid comprises: Determine whether the oscillation amplitude and oscillation frequency of the active power value at the power transmission collection point meet the preset broadband oscillation conditions.

8. An oscillation suppression device for a new energy power generation cluster, characterized in that: include: Electrical quantity monitoring module, processor, communication module; An electrical quantity monitoring module, used to monitor the electrical quantity at the power transmission collection point of the new energy power generation cluster; A processor is configured to perform the following processing: Based on the electrical quantity at the power transmission collection point of the new energy power generation cluster, determining whether the overall oscillation condition at the power transmission collection point meets the preset oscillation condition; In response to satisfying the preset oscillation condition, determining the active power compensation value of each new energy generator set in the new energy power generation cluster based on the equivalent electrical distance between each new energy generator set and the power transmission collection point and the current active power value; Controlling the communication module to distribute respective active power compensation values ​​to each of the new energy generating sets, so as to control each of the new energy generating sets to achieve optimal damping compensation for the active power output of a single machine; The power transmission junction is connected to the AC side of a nearby flexible DC transmission device, and the DC side of the flexible DC transmission device is used to transmit flexible DC power.

9. The oscillation suppression device according to claim 8, characterized in that: The electrical quantity monitoring module is connected to the power transmission collection point.

10. A new energy power generation cluster, characterized in that: include: A plurality of new energy generating sets and an oscillation suppression device as claimed in claim 8 or 9.

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