A virtual damping winding control method and system for a grid-type converter

Abstract

This application belongs to the field of new energy power generation technology, specifically disclosing a virtual damping winding control method and system for a grid-type converter. This method is applied to a grid-type converter and includes: acquiring instantaneous voltage information at the common junction point of the rotor damping winding branch, rotor excitation winding branch, armature winding branch, and stator winding branch of the synchronous machine simulated by the grid-type converter; determining the target potential amplitude information based on the instantaneous voltage information, the leakage reactance information of the rotor damping winding branch, the leakage reactance information of the rotor excitation winding branch, and the armature reaction reactance information of the armature winding branch; and adjusting the internal potential information of the grid-type converter based on the target potential amplitude information. Through this application, the grid-type converter can simulate the reactive power support characteristics of a synchronous machine with damping windings during transient periods, effectively improving the spontaneous reactive power response capability of existing grid-type converters and suppressing rapid fluctuations in grid voltage.

Description

Technical Field

[0001] This application belongs to the field of new energy power generation technology, and more specifically, relates to a virtual damping winding control method and system for a grid-type converter. Background Technology

[0002] With the rapid development of new power systems based on new energy sources, power electronic equipment, represented by wind and solar converters, has been introduced into the power grid on a large scale. This has led to the power system exhibiting characteristics of low inertia support and low short-circuit capacity, highlighting the challenges of safe and stable operation. In recent years, to improve the active voltage / frequency support capability of new energy power generation equipment for the power grid, control methods for grid-forming (GFM) converters, represented by Virtual Synchronous Generator (VSG) control, have received widespread attention. Regarding voltage support, when the external voltage drops or rises, similar to a synchronous machine, VSG control can maintain the voltage amplitude of the converter's internal potential without sudden changes, thereby spontaneously outputting or absorbing reactive power to support the grid voltage.

[0003] In power systems, due to the presence of some reactive loads (such as electric arc furnaces in steel plants, start-up and shutdown of large asynchronous motors, etc.) and abnormal operating conditions such as high-voltage DC transmission blocking, the power grid may experience rapid reactive disturbances on a time scale of 100ms or even shorter. Therefore, this severely tests the spontaneous reactive response capability of the GFM converter.

[0004] However, the reactive power loop of existing VSG control is relatively simple, and usually adopts a virtual excitation control scheme. That is, the existing GFM converter only simulates the rotor excitation winding of the traditional synchronous machine, while ignoring the reactive power support of other internal factors. As a result, the spontaneous reactive power response capability of the GFM converter is limited, and its ability to suppress rapid fluctuations in grid voltage needs to be further improved.

[0005] Therefore, how to further improve the spontaneous reactive power response capability of GFM converters has become a technical problem that the industry urgently needs to solve. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of this application is to improve the spontaneous reactive power response capability of the existing GFM converter in order to suppress the rapid fluctuation of grid voltage.

[0007] To achieve the above objectives, in a first aspect, this application provides a virtual damping winding control method for a grid-type converter, applied to a grid-type converter. The equivalent circuit of the synchronous machine simulated by the grid-type converter includes a stator winding branch, a rotor excitation winding branch, and an armature winding branch. The equivalent circuit also includes a rotor damping winding branch. The method includes:

[0008] The instantaneous voltage information at the common junction point of the rotor damping winding branch, the rotor excitation winding branch, the armature winding branch, and the stator winding branch of the synchronous machine simulated by the grid-type converter is obtained.

[0009] Based on the instantaneous voltage information, the leakage reactance information of the rotor damping winding branch, the leakage reactance information of the rotor excitation winding branch, and the armature reaction reactance information of the armature winding branch, the target potential amplitude information introduced by the rotor damping winding branch is determined.

[0010] The internal potential information of the grid-type converter is adjusted based on the target potential amplitude information.

[0011] Optionally, adjusting the internal potential information of the grid-type converter based on the target potential amplitude information includes:

[0012] Obtain the reference information of the first internal potential amplitude of the grid-type converter in the virtual excitation control mode;

[0013] Based on the target potential amplitude information and the first internal potential amplitude reference information, the second internal potential amplitude reference information is determined;

[0014] The internal potential information of the grid-type converter is adjusted based on the second internal potential amplitude reference information.

[0015] Optionally, adjusting the internal potential information of the grid-type converter based on the second internal potential amplitude reference information includes:

[0016] Obtain internal potential phase reference information; the internal potential phase reference information is determined based on the output active power information of the grid-type converter;

[0017] Based on the second internal potential amplitude reference information and the internal potential phase reference information, the target internal potential reference information is determined;

[0018] A target PWM modulation signal is generated based on the target internal potential reference information;

[0019] Based on the target PWM modulation signal, the switching transistors of the grid converter are controlled to operate to the target switching transistor state, so that the grid converter can generate internal potential information under the target switching transistor state.

[0020] Optionally, before obtaining the first internal potential amplitude reference information of the grid-type converter in virtual excitation control mode, the method further includes:

[0021] Obtain the output voltage amplitude information and output reactive power information of the grid-type converter;

[0022] Based on the output voltage amplitude information, the output reactive power information, the preset reference voltage amplitude information, and the preset reference reactive power information, the first internal potential amplitude reference information is determined.

[0023] Optionally, before acquiring the internal potential phase reference information, the method further includes:

[0024] Obtain the output active power information of the grid-type converter;

[0025] Based on the output active power information, the preset converter reference angular velocity information, and the preset reference active power information, the internal potential phase reference information is determined.

[0026] Optionally, determining the target potential amplitude information introduced by the rotor damping winding branch based on the instantaneous voltage information, the leakage reactance information of the rotor damping winding branch, the leakage reactance information of the rotor excitation winding branch, and the armature reaction reactance information of the armature winding branch includes:

[0027] Determine the first product of the armature reaction reactance information and the leakage reactance information of the rotor excitation winding branch, and determine the summation result of the armature reaction reactance information and the leakage reactance information of the rotor excitation winding branch;

[0028] Determine the second product of the summation result and the leakage reactance information of the rotor damping winding branch;

[0029] The ratio of the first product to the second product is multiplied by the instantaneous voltage information to obtain the target potential amplitude information.

[0030] Secondly, this application provides a virtual damping winding control system for a grid-type converter, applied to a grid-type converter. The equivalent circuit of the synchronous machine simulated by the grid-type converter includes a stator winding branch, a rotor excitation winding branch, and an armature winding branch. The equivalent circuit also includes a rotor damping winding branch. The system includes:

[0031] The acquisition module is used to acquire instantaneous voltage information at the common intersection point of the rotor damping winding branch, the rotor excitation winding branch, the armature winding branch, and the stator winding branch;

[0032] The processing module is used to determine the target potential amplitude information introduced by the rotor damping winding branch based on the instantaneous voltage information, the leakage reactance information of the rotor damping winding branch, the leakage reactance information of the rotor excitation winding branch, and the armature reaction reactance information of the armature winding branch.

[0033] The control module is used to adjust the internal potential information of the grid-type converter based on the target potential amplitude information.

[0034] Thirdly, this application provides an electronic device, comprising: at least one memory for storing a program; and at least one processor for executing the program stored in the memory, wherein when the program stored in the memory is executed, the processor is configured to execute the method described in the first aspect or any possible implementation thereof.

[0035] Fourthly, this application provides a computer-readable storage medium storing a computer program that, when run on a processor, causes the processor to perform the method described in the first aspect or any possible implementation thereof.

[0036] Fifthly, this application provides a computer program product that, when run on a processor, causes the processor to perform the method described in the first aspect or any possible implementation thereof.

[0037] It is understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here.

[0038] Overall, the technical solutions conceived in this application have the following beneficial effects compared with the prior art:

[0039] This application provides a virtual damping winding control method and system for a grid-type converter. By retaining the existing virtual excitation loop of VSG control, an additional potential circuit is introduced to simulate the reactive power support effect of the rotor damping winding branch in a traditional synchronous machine. That is, equivalent circuit analysis is performed on the synchronous machine with damping winding during transients to solve for the potential amplitude information reflecting the voltage support effect of the rotor damping winding. Then, the internal potential information of the GFM converter is dynamically adjusted in real time using this potential amplitude information. This allows the grid-type converter to simulate the reactive power support characteristics of a synchronous machine with damping winding during transients, effectively improving the spontaneous reactive power response capability of the GFM converter and suppressing rapid fluctuations in grid voltage. Attached Figure Description

[0040] Figure 1 This is a flowchart illustrating the virtual damping winding control method for a GFM converter provided in an embodiment of this application.

[0041] Figure 2 This is a schematic diagram showing the correspondence between a GFM converter using traditional virtual synchronous control and a traditional synchronous machine with undamped windings.

[0042] Figure 3 This is a schematic diagram showing the correspondence between a GFM converter with virtual damping windings and a conventional synchronous machine with damping windings provided in the embodiments of this application;

[0043] Figure 4 This is a schematic diagram of the main circuit topology of the GFM converter with virtual damping winding provided in the embodiments of this application;

[0044] Figure 5 This is a schematic diagram of the control structure of a GFM converter with a virtual damping winding provided in an embodiment of this application;

[0045] Figure 6 (a) is a schematic diagram comparing the disturbance changes of the grid connection point voltage between the control method provided in this application embodiment and the traditional virtual synchronous control method; (b) is a schematic diagram comparing the disturbance changes of the converter output reactive power between the control method provided in this application embodiment and the traditional virtual synchronous control method; (c) is a schematic diagram comparing the disturbance changes of the converter internal potential between the control method provided in this application embodiment and the traditional virtual synchronous control method.

[0046] Figure 7 This is a schematic diagram of the structure of the GFM converter virtual damping winding control system provided in the embodiments of this application;

[0047] Figure 8 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0049] The terms "first" and "second," etc., used in the specification and claims of this application are used to distinguish different objects, not to describe a specific order of objects. For example, "first internal potential amplitude reference information" and "second internal potential amplitude reference information" are used to distinguish converter internal potential amplitude reference information under different modes, not to describe a specific order of converter internal potential amplitude reference information.

[0050] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0051] In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more, for example, multiple computer instructions means two or more computer instructions, etc.

[0052] The embodiments of this application are described below with reference to the accompanying drawings.

[0053] Figure 1 This is a flowchart illustrating the virtual damping winding control method for a GFM converter provided in this application embodiment. This control method can be applied to GFM converters. The equivalent circuit of the synchronous machine simulated by the GFM converter includes a stator winding branch, a rotor excitation winding branch, and an armature winding branch. Furthermore, the equivalent circuit also includes a rotor damping winding branch, such as... Figure 1 As shown, the method includes:

[0054] Step S1: Obtain the instantaneous voltage information at the common junction point of the rotor damping winding branch, rotor excitation winding branch, armature winding branch and stator winding branch of the synchronous machine simulated by the GFM converter.

[0055] Step S2: Based on the instantaneous voltage information, the leakage reactance information of the rotor damping winding branch, the leakage reactance information of the rotor excitation winding branch, and the armature reaction reactance information of the armature winding branch, determine the target potential amplitude information introduced by the rotor damping winding branch.

[0056] Step S3: Adjust the internal potential information of the GFM converter based on the target potential amplitude information.

[0057] Specifically, the target potential amplitude information described in the embodiments of this application refers to the additional potential amplitude information that reflects the voltage support effect of the rotor damping winding after the rotor damping winding branch is introduced into the equivalent circuit of the synchronous machine simulated by the GFM converter. It can be expressed as follows: .

[0058] In the embodiments of this application, while retaining the existing virtual excitation loop controlled by VSG, an additional potential loop is introduced to simulate the reactive power support effect of the rotor damping winding branch in a traditional synchronous machine.

[0059] Figure 2 This is a schematic diagram showing the correspondence between a GFM converter using traditional virtual synchronous control and a traditional synchronous machine with undamped windings, as shown below. Figure 2 As shown, in the traditional virtual excitation control mode, the GFM converter only simulates the rotor excitation winding of a traditional synchronous machine. Its reactive power support capability is equivalent to that of a synchronous machine without damping windings. The equivalent circuit of the synchronous machine simulated by the converter includes the stator winding branch (…). Branch circuit), rotor excitation winding branch circuit ( - Branch circuits) and armature winding branches ( (Side road).

[0060] here, This represents the actual filter inductance of the converter. EThis indicates the reference information for the internal potential amplitude of the converter. This indicates the flux linkage information of the excitation winding of the simulated synchronous machine. 、 、 These represent the leakage reactance information of the stator winding branch, the rotor excitation winding branch, and the armature winding branch of the simulated synchronous machine, respectively. d Armature reaction reactance information in the axial direction; This indicates the instantaneous voltage amplitude at the intersection of the three branches during a system transient (when the grid voltage changes abruptly). This indicates the instantaneous voltage amplitude at the grid connection point during system transients; This represents the line impedance on the power grid side, including line resistance. and line reactance ; This indicates the voltage amplitude information on the grid side during system transients.

[0061] The above information has the following correspondence: ; .

[0062] Figure 3 This is a schematic diagram showing the correspondence between a GFM converter with a virtual damping winding and a conventional synchronous machine with a damping winding, as provided in the embodiments of this application. Figure 3 As shown, in the embodiments of this application, a rotor damping winding branch is further introduced based on the existing VSG control. - (Branch), as shown in the figure, has a damping winding synchronous machine equivalent circuit during the transient period, in which, This indicates the damping winding flux linkage information of the simulated synchronous machine. This indicates the leakage reactance information of the rotor damping winding branch of the simulated synchronous machine. The symbol "-" indicates series connection.

[0063] In the embodiments of this application, the equivalent circuit of the synchronizer is transformed through circuit equivalence transformation. branch road and - Branch equivalent conversion - Branch roads, among which, .

[0064] Furthermore, by treating the output reactive current as equivalent to a single feeder... - Side road, take ,in, This indicates the steady-state voltage amplitude at the intersection of the four branches during normal steady-state operation of the system.

[0065] in, .

[0066] Consequently, in the corresponding GFM converter grid-connected circuit with virtual damping windings, the reference information for the converter's internal potential amplitude becomes... Converter filter reactance constant.

[0067] In practical applications, this involves measuring the instantaneous voltage amplitude at the intersection of each branch. At this time, the converter filter reactance can be... Divided into and The two parts, the voltage amplitude information at the node is the dividing point. ,Right now Voltage amplitude information at grid connection point The impedance between them is The internal potential output at the converter bridge arm port is... The impedance between them is . steady-state value It can be regarded as the damping winding flux of the simulated synchronous machine, that is .

[0068] Furthermore, continue to refer to Figure 3 In step S1, during the operation of the GFM converter, the equivalent circuit data can be acquired in real time. - Side roads - Side roads branch road and Instantaneous voltage information at the common junction of branches .

[0069] In the embodiments of this application, in step S2, based on instantaneous voltage information , - Leakage reactance information of branch , - Leakage reactance information of branch and armature reaction reactance information of the branch Substituting these values ​​into the preset calculation formula, the target potential amplitude introduced by the rotor damping winding branch can be determined. .

[0070] More specifically, target potential amplitude information The calculation formula can be expressed as follows:

[0071] .

[0072] More specifically, the calculation method for determining the target potential amplitude information is as follows:

[0073] Determine armature reaction reactance information and leakage resistance information The first product, i.e. And determine armature reaction reactance information. With leakage resistance information The summation result, i.e. ;

[0074] The second product of the summation result and the leakage reactance information of the rotor damping winding branch is obtained. .

[0075] The ratio of the first product to the second product With instantaneous voltage information Perform multiplication to obtain the target potential amplitude information. .

[0076] Furthermore, in the embodiments of this application, in step S3, based on the target potential amplitude information according to the preset control strategy... Adjust the internal potential information of the GFM converter.

[0077] Figure 4 This is a schematic diagram of the main circuit topology of the GFM converter with virtual damping winding provided in the embodiments of this application, as shown below. Figure 4 As shown in the embodiments of this application, the GFM converter control structure specifically includes two types of control loops: an active-frequency loop and a reactive-voltage loop. The active-frequency loop control loop is used to determine the phase reference information of the internal potential of the GFM converter. The reactive power-voltage loop control is used to determine the amplitude reference information of the internal potential of the GFM converter. .

[0078] Based on the above embodiments, as an optional embodiment, step S3, adjusting the internal potential information of the GFM converter based on the target potential amplitude information, includes:

[0079] Obtain the reference information of the first internal potential amplitude of the GFM converter in virtual excitation control mode;

[0080] Based on the target potential amplitude information and the first internal potential amplitude reference information, the second internal potential amplitude reference information is determined;

[0081] The internal potential information of the GFM converter is adjusted based on the second internal potential amplitude reference information.

[0082] Specifically, the first internal potential amplitude reference information described in the embodiments of this application refers to the internal potential amplitude reference information of the GFM converter in the virtual excitation control mode, i.e., the parameter. E .

[0083] The second internal potential amplitude reference information described in the embodiments of this application refers to the information introduced... - After the branch, the internal potential amplitude reference information of the GFM converter, i.e., the parameters .

[0084] In the embodiments of this application, the first internal potential amplitude reference information is pre-calculated. E， Therefore, the reference information of the first internal potential amplitude can be used. E Proceed to the next calculation.

[0085] Based on the above embodiments, as an optional embodiment, before obtaining the first internal potential amplitude reference information of the GFM converter in virtual excitation control mode, the method further includes:

[0086] Obtain the output voltage amplitude information and output reactive power information of the GFM converter;

[0087] Based on the output voltage amplitude information, output reactive power information, preset reference voltage amplitude information, and preset reference reactive power information, the first internal potential amplitude reference information is determined.

[0088] Figure 5 This is a schematic diagram of the control structure of a GFM converter with a virtual damping winding provided in an embodiment of this application, as shown below. Figure 5 As shown in the embodiments of this application, in the reactive power-voltage loop control loop, the output voltage amplitude information of the GFM converter is obtained. and output reactive power information and preset reference voltage amplitude information and preset reference reactive power information Determine the reference information for the amplitude of the first internal potential. E Among them, the preset reference voltage amplitude information and preset reference reactive power information All settings can be configured according to user instructions.

[0089] Specifically, in the embodiments of this application, the original amplitude reference signal output by the GFM converter under virtual excitation control mode, i.e., the first internal potential amplitude reference information, is... E Satisfy the following expression:

[0090] ;

[0091] In the formula, This represents the reactive power-voltage droop coefficient; This represents the reactive power loop integral coefficient.

[0092] Furthermore, in the embodiments of this application, based on the target potential amplitude information and first internal potential amplitude reference information E The reference information for the amplitude of the second internal potential can be determined. The calculation formula is as follows:

[0093] ;

[0094] The improved mathematical model of the reactive power-voltage loop can be expressed as:

[0095] ;

[0096] Furthermore, based on the second internal potential amplitude reference information Adjust the internal potential information of the GFM converter.

[0097] Based on the above embodiments, as an optional embodiment, adjusting the internal potential information of the GFM converter based on the second internal potential amplitude reference information includes:

[0098] Obtain internal potential phase reference information; the internal potential phase reference information is determined based on the output active power information of the GFM converter;

[0099] Based on the second internal potential amplitude reference information and internal potential phase reference information, the target internal potential reference information is determined.

[0100] Generate the target PWM modulation signal based on the target internal potential reference information;

[0101] The switching transistors of the GFM converter are controlled to operate to the target switching transistor state based on the target PWM modulation signal, so that the GFM converter can generate internal potential information under the target switching transistor state.

[0102] Specifically, in the embodiments of this application, in the implementation of adjusting the internal potential information of the GFM converter, the internal potential phase reference information is first obtained. .

[0103] Continue to refer to Figure 5 In embodiments of this application, before obtaining the internal potential phase reference information, the method further includes:

[0104] Obtain the output active power information of the GFM converter;

[0105] Based on the output active power information, the preset converter reference angular velocity information, and the preset reference active power information, the internal potential phase reference information is determined.

[0106] Specifically, in the embodiments of this application, in the active-frequency loop control loop, the output active power information of the GFM converter is obtained. and preset converter reference angular velocity information and preset reference active power information The phase reference information of the internal potential of the GFM converter is determined. Among them, the preset converter reference angular velocity information and preset reference active power information All settings can be configured according to user instructions.

[0107] More specifically, in the embodiments of this application, internal potential phase reference information The solution can be obtained through the following mathematical model of the active-frequency loop:

[0108] ;

[0109] In the formula, Indicates the angular velocity of the converter. Indicates the system damping coefficient; J This represents the system's virtual inertia.

[0110] Furthermore, continue to refer to Figure 4 Reference information based on the internal potential amplitude of the converter and internal potential phase reference information Once the target internal potential reference information is determined, the complete parameter information that the converter's internal potential needs to satisfy can be obtained.

[0111] Furthermore, by using the PWM modulation method, a target PWM modulation signal is generated using the target internal potential reference information calculated above. Then, the target PWM modulation signal can be used to control the switching transistor of the GFM converter to operate to the target switching transistor state. The GFM converter then generates the internal potential information under the target switching transistor state, thereby realizing real-time dynamic adjustment of the internal potential information of the GFM converter.

[0112] In the embodiments of this application, during normal steady-state operation, the voltage amplitude within the GFM converter satisfies ,in Information on the instantaneous voltage amplitude at the intersection of each branch. steady-state value, for The steady-state value. During the dynamic process of a sudden drop / increase in grid voltage, due to the output under virtual excitation control mode. EThe voltage remains constant, therefore, the voltage inside the converter remains constant during voltage surges. satisfy:

[0113]

[0114] ;

[0115] It can be seen that, That is, in a dynamic process The change in voltage is negative during sudden drops and positive during sudden increases, effectively suppressing rapid fluctuations in grid voltage.

[0116] Among them, the change in internal potential This refers to the role of the virtual damping winding in reactive power support.

[0117] For example, taking the grid voltage sudden drop condition as an example, the internal potential amplitude of the GFM converter can suddenly increase, and the sudden increase is: In contrast, existing grid-type control strategies for converters can only maintain a constant internal potential amplitude during voltage dips. Therefore, the virtual damping winding control method provided in this application can enable the converter to have a stronger self-generated reactive power support capability than converters using existing grid-type control strategies.

[0118] The virtual damping winding control method for GFM converters in this application introduces an additional potential circuit to simulate the reactive power support of the rotor damping winding branch in a traditional synchronous machine, while retaining the existing virtual excitation loop of VSG control. Specifically, it performs equivalent circuit analysis on a synchronous machine with damping windings during transient periods, solves for the potential amplitude information reflecting the voltage support effect of the rotor damping winding, and then uses this potential amplitude information to dynamically adjust the internal potential information of the GFM converter in real time. This allows the grid-type converter to simulate the reactive power support characteristics of a synchronous machine with damping windings during transient periods, effectively improving the spontaneous reactive power response capability of the GFM converter and suppressing rapid fluctuations in grid voltage.

[0119] In one specific embodiment of this application, in order to verify the effectiveness of the virtual damping winding control method of the GFM converter in this application, a simulation study was carried out using a GFM converter as an example. The system parameters used are shown in Table 1, and the control parameters are shown in Table 2.

[0120] Table 1

[0121]

[0122] Table 2

[0123]

[0124] Build a simulation platform in Matlab / Simulink Figure 4 The circuit model shown is used for simulation under the following conditions: t At 5s, a reactive load of 0.5pu is applied at the grid connection point, and the load is disconnected 100ms later to simulate a rapid voltage fluctuation event in the system.

[0125] The results of using the virtual damping winding control method provided in the embodiments of this application for GFM converters are as follows: Figure 6 As shown.

[0126] Figure 6 (a) is a schematic diagram comparing the disturbance changes of the grid connection point voltage between the control method provided in this application embodiment and the traditional virtual synchronous control method; (b) is a schematic diagram comparing the disturbance changes of the converter output reactive power between the control method provided in this application embodiment and the traditional virtual synchronous control method; (c) is a schematic diagram comparing the disturbance changes of the converter internal potential between the control method provided in this application embodiment and the traditional virtual synchronous control method. Figure 6 As shown in (a), the voltage amplitude at the grid connection point drops significantly under traditional virtual synchronous control, while the minimum voltage amplitude and rate of change at the grid connection point are significantly improved under the virtual damping winding control provided in this application embodiment.

[0127] like Figure 6 As shown in (b) of the paper, under traditional virtual synchronous control, the converter's spontaneous reactive power response is relatively small after a disturbance occurs. However, under the virtual damping winding control provided in this application embodiment, the converter generates a stronger spontaneous reactive power response to support grid voltage stability after the grid connection point is lowered.

[0128] like Figure 6 As shown in (c), under traditional virtual synchronous control, the internal voltage of the bridge arm output of the converter can only remain unchanged momentarily after a disturbance occurs. However, under the virtual damping winding control provided in this application embodiment, the internal voltage of the bridge arm output of the converter can spontaneously and instantaneously increase momentarily after a disturbance occurs, thus achieving a stronger voltage support effect.

[0129] The virtual damping winding control system for the GFM converter provided in this application is described below. The virtual damping winding control system for the GFM converter described below can be referred to in correspondence with the virtual damping winding control method for the GFM converter described above.

[0130] Figure 7 This is a schematic diagram of the virtual damping winding control system for a GFM converter provided in an embodiment of this application. This system can be applied to GFM converters. The equivalent circuit of the synchronous machine simulated by the GFM converter includes stator winding branches, rotor excitation winding branches, and armature winding branches. The equivalent circuit also includes a rotor damping winding branch, such as... Figure 7 As shown, the system includes:

[0131] The acquisition module 10 is used to acquire the instantaneous voltage information at the common junction point of the rotor damping winding branch, rotor excitation winding branch, armature winding branch and stator winding branch of the synchronous machine simulated by the GFM converter.

[0132] The processing module 20 is used to determine the target potential amplitude information introduced by the rotor damping winding branch based on the instantaneous voltage information, the leakage reactance information of the rotor damping winding branch, the leakage reactance information of the rotor excitation winding branch, and the armature reaction reactance information of the armature winding branch.

[0133] The control module 30 is used to adjust the internal potential information of the GFM converter based on the target potential amplitude information.

[0134] It is understood that the detailed functional implementation of each of the above units / modules can be found in the description in the aforementioned method embodiments, and will not be repeated here.

[0135] It should be understood that the above-described device is used to execute the methods in the above embodiments. The implementation principle and technical effect of the corresponding program modules in the device are similar to those described in the above methods. The working process of the device can be referred to the corresponding process in the above methods, and will not be repeated here.

[0136] The virtual damping winding control system of the GFM converter in this application introduces an additional potential circuit to simulate the reactive power support of the rotor damping winding branch in a traditional synchronous machine, while retaining the virtual excitation loop of the existing VSG control. That is, it performs equivalent circuit analysis on the synchronous machine with damping winding during transients, solves for the potential amplitude information reflecting the voltage support effect of the rotor damping winding, and then uses this potential amplitude information to dynamically adjust the internal potential information of the GFM converter in real time. This allows the grid-type converter to simulate the reactive power support characteristics of a synchronous machine with damping winding during transients, effectively improving the spontaneous reactive power response capability of the GFM converter and suppressing rapid fluctuations in grid voltage.

[0137] Based on the methods in the above embodiments, this application provides an electronic device, such as... Figure 8 As shown, the electronic device may include a processor 810, a communications interface 820, a memory 830, and a communication bus 840, wherein the processor 810, the communications interface 820, and the memory 830 communicate with each other via the communication bus 840. The processor 810 can call logical instructions in the memory 830 to execute the methods in the above embodiments.

[0138] Furthermore, the logical instructions in the aforementioned memory 830 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.

[0139] Based on the methods in the above embodiments, this application provides a computer-readable storage medium storing a computer program that, when run on a processor, causes the processor to execute the methods in the above embodiments.

[0140] Based on the methods in the above embodiments, this application provides a computer program product that, when run on a processor, causes the processor to execute the methods in the above embodiments.

[0141] It is understood that the processor in the embodiments of this application can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. A general-purpose processor can be a microprocessor or any conventional processor.

[0142] The method steps in this application embodiment can be implemented in hardware or by a processor executing software instructions. The software instructions can consist of corresponding software modules, which can be stored in random access memory (RAM), flash memory, read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, hard disks, portable hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can reside in an ASIC.

[0143] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted through the computer-readable storage medium. The computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid-state disk (SSD)).

[0144] It is understood that the various numerical designations used in the embodiments of this application are merely for the convenience of description and are not intended to limit the scope of the embodiments of this application.

[0145] It should be understood that expressions such as “comprising” and “may include” used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as “comprising” and / or “having” are to be interpreted as indicating a particular characteristic, number, operation, constituent element, component, or combination thereof, but not to exclude the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0146] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A virtual damping winding control method for a grid-type converter, applied to a grid-type converter, wherein the equivalent circuit of the synchronous machine simulated by the grid-type converter includes a stator winding branch, a rotor excitation winding branch, and an armature winding branch, characterized in that, The equivalent circuit further includes a rotor damping winding branch, and the method includes: The instantaneous voltage information at the common junction point of the rotor damping winding branch, the rotor excitation winding branch, the armature winding branch, and the stator winding branch of the synchronous machine simulated by the grid-type converter is obtained. Based on the instantaneous voltage information, the leakage reactance information of the rotor damping winding branch, the leakage reactance information of the rotor excitation winding branch, and the armature reaction reactance information of the armature winding branch, the target potential amplitude information introduced by the rotor damping winding branch is determined. The internal potential information of the grid-type converter is adjusted based on the target potential amplitude information; The step of determining the target potential amplitude information introduced by the rotor damping winding branch based on the instantaneous voltage information, the leakage reactance information of the rotor damping winding branch, the leakage reactance information of the rotor excitation winding branch, and the armature reaction reactance information of the armature winding branch includes: Determine the first product of the armature reaction reactance information and the leakage reactance information of the rotor excitation winding branch, and determine the summation result of the armature reaction reactance information and the leakage reactance information of the rotor excitation winding branch; Determine the second product of the summation result and the leakage reactance information of the rotor damping winding branch; The ratio of the first product to the second product is multiplied by the instantaneous voltage information to obtain the target potential amplitude information.

2. The virtual damping winding control method for a grid-type converter according to claim 1, characterized in that, The adjustment of the internal potential information of the grid-type converter based on the target potential amplitude information includes: Obtain the reference information of the first internal potential amplitude of the grid-type converter in the virtual excitation control mode; Based on the target potential amplitude information and the first internal potential amplitude reference information, the second internal potential amplitude reference information is determined; The internal potential information of the grid-type converter is adjusted based on the second internal potential amplitude reference information.

3. The virtual damping winding control method for a grid-type converter according to claim 2, characterized in that, The adjustment of the internal potential information of the grid-type converter based on the second internal potential amplitude reference information includes: Obtain internal potential phase reference information; the internal potential phase reference information is determined based on the output active power information of the grid-type converter; Based on the second internal potential amplitude reference information and the internal potential phase reference information, the target internal potential reference information is determined; A target PWM modulation signal is generated based on the target internal potential reference information; Based on the target PWM modulation signal, the switching transistors of the grid converter are controlled to operate to the target switching transistor state, so that the grid converter can generate internal potential information under the target switching transistor state.

4. The virtual damping winding control method for a grid-type converter according to claim 2, characterized in that, Before obtaining the first internal potential amplitude reference information of the grid-type converter in virtual excitation control mode, the method further includes: Obtain the output voltage amplitude information and output reactive power information of the grid-type converter; Based on the output voltage amplitude information, the output reactive power information, the preset reference voltage amplitude information, and the preset reference reactive power information, the first internal potential amplitude reference information is determined.

5. The virtual damping winding control method for a grid-type converter according to claim 3, characterized in that, Before acquiring the internal potential phase reference information, the method further includes: Obtain the output active power information of the grid-type converter; Based on the output active power information, the preset converter reference angular velocity information, and the preset reference active power information, the internal potential phase reference information is determined.

6. A virtual damping winding control system for a grid-type converter, applied to a grid-type converter, wherein the equivalent circuit of the synchronous machine simulated by the grid-type converter includes a stator winding branch, a rotor excitation winding branch, and an armature winding branch, characterized in that, The equivalent circuit further includes a rotor damping winding branch, and the system includes: The acquisition module is used to acquire instantaneous voltage information at the common intersection point of the rotor damping winding branch, the rotor excitation winding branch, the armature winding branch, and the stator winding branch; The processing module is used to determine the target potential amplitude information introduced by the rotor damping winding branch based on the instantaneous voltage information, the leakage reactance information of the rotor damping winding branch, the leakage reactance information of the rotor excitation winding branch, and the armature reaction reactance information of the armature winding branch. The control module is used to adjust the internal potential information of the grid-type converter based on the target potential amplitude information; Specifically, the processing module is used for: Determine the first product of the armature reaction reactance information and the leakage reactance information of the rotor excitation winding branch, and determine the summation result of the armature reaction reactance information and the leakage reactance information of the rotor excitation winding branch; Determine the second product of the summation result and the leakage reactance information of the rotor damping winding branch; The ratio of the first product to the second product is multiplied by the instantaneous voltage information to obtain the target potential amplitude information.

7. An electronic device, characterized in that, include: At least one memory for storing computer programs; At least one processor is configured to execute a program stored in the memory, wherein when the program stored in the memory is executed, the processor is configured to perform the method as described in any one of claims 1-5.

8. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is run on the processor, it causes the processor to perform the method as described in any one of claims 1-5.

9. A computer program product, characterized in that, When the computer program product is run on a processor, the processor causes the processor to perform the method as described in any one of claims 1-5.

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