Method and system for controlling virtual damping winding of network construction type converter

Abstract

The invention belongs to the technical field of new energy power generation, and particularly discloses a virtual damping winding control method and system for a grid-forming converter. The method is applied to a network-forming converter, and comprises the following steps: acquiring instantaneous voltage information at a common connection intersection point of a rotor damping winding branch, a rotor excitation winding branch, an armature winding branch and a stator winding branch of a synchronous machine simulated by the network-forming converter; target potential amplitude information is determined 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 network-forming converter based on the target potential amplitude information. According to the method and the device, the reactive support characteristic of the synchronous machine with the damping winding can be simulated by the network construction type converter in the transient state period, the spontaneous reactive response capability of the existing network construction type converter is effectively improved, and the suppression of the rapid fluctuation of the power grid voltage is realized.

Description

Technical Field

[0001] The present application belongs to the field of renewable energy power generation technology, and more specifically, to a virtual damping winding control method and system for a grid-connected converter. Background Art

[0002] With the rapid development of new power systems dominated by renewable energy, power electronic equipment represented by wind and solar converters have been introduced into the power grid on a large scale. The power system has shown the characteristics of low inertia support and low short-circuit capacity, and the problem of safe and stable operation has become prominent. In recent years, in order to improve the active voltage / frequency support capability of renewable energy power generation equipment for the power grid, the control method of grid-forming (GFM) converter represented by virtual synchronous generator (VSG) control has received widespread attention. In terms of voltage support, when the external voltage drops or rises, similar to the synchronous machine, VSG control can maintain the voltage amplitude of the potential inside the converter without sudden changes, and then spontaneously output or absorb reactive power to support the grid voltage.

[0003] In the power system, due to the existence of abnormal operating conditions such as some reactive loads (such as steel plant arc furnaces, start and stop of large asynchronous motors, etc.) and high-voltage DC transmission interlocks, the power grid may experience rapid reactive disturbances of 100ms or even shorter time scales. Therefore, this is a great test of the spontaneous reactive response capability of the GFM converter.

[0004] However, the reactive loop of existing VSG control is relatively simple, and a virtual excitation control scheme is usually adopted. That is, the existing GFM converter only simulates the rotor excitation winding of the traditional synchronous machine, while ignoring the reactive support effect of other internal factors. As a result, the spontaneous reactive response capability of the GFM converter is limited, and the 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 the GFM converter has become a technical problem that needs to be solved urgently in the industry. Summary of the invention

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

[0007] To achieve the above-mentioned purpose, in a first aspect, the present application provides a virtual damping winding control method for a grid-type converter, which is applied to a grid-type converter, wherein the equivalent circuit of a synchronous machine simulated by the grid-type converter includes a stator winding branch, a rotor excitation winding branch and an armature winding branch, and the equivalent circuit also includes a rotor damping winding branch, and the method includes: Acquire instantaneous voltage information at a common intersection of a rotor damping winding branch, a rotor excitation winding branch, an armature winding branch and a stator winding branch of a synchronous machine simulated by the grid-type converter; Determining 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 internal potential information of the grid-connected converter is adjusted based on the target potential amplitude information.

[0008] Optionally, adjusting the internal potential information of the grid-connected converter based on the target potential amplitude information includes: Acquiring first internal potential amplitude reference information of the grid-connected converter in a virtual excitation control mode; determining second internal potential amplitude reference information based on the target potential amplitude information and the first internal potential amplitude reference information; The internal potential information of the grid-connected converter is adjusted based on the second internal potential amplitude reference information.

[0009] Optionally, adjusting the internal potential information of the grid-connected converter based on the second internal potential amplitude reference information includes: Acquiring 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; determining target internal potential reference information based on the second internal potential amplitude reference information and the internal potential phase reference information; generating a target PWM modulation signal based on the target internal potential reference information; Based on the target PWM modulation signal, the switch tube of the grid-type converter is controlled to operate to a target switch tube state, so that the grid-type converter generates internal potential information under the target switch tube state.

[0010] Optionally, before obtaining the first internal potential amplitude reference information of the grid-connected converter in the virtual excitation control mode, the method further includes: Obtaining output voltage amplitude information and output reactive power information of the grid-connected converter; The first internal potential amplitude reference information is determined 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.

[0011] Optionally, before acquiring the internal potential phase reference information, the method further includes: Obtaining output active power information of the grid-connected converter; The internal potential phase reference information is determined based on the output active power information, the preset converter reference angular velocity information and the preset reference active power information.

[0012] 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: Determine a first product of the armature reaction reactance information and the leakage reactance information of the rotor excitation winding branch, and determine a summation result of the armature reaction reactance information and the leakage reactance information of the rotor excitation winding branch; Determine a second product of the summation result and the leakage reactance information of the rotor damping winding branch; The target potential amplitude information is obtained by multiplying the ratio of the first product to the second product by the instantaneous voltage information.

[0013] In a second aspect, the present application provides a virtual damping winding control system for a grid-type converter, which is 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, and the equivalent circuit also includes a rotor damping winding branch. The system includes: An acquisition module, used to acquire instantaneous voltage information at a common intersection of the rotor damping winding branch, the rotor excitation winding branch, the armature winding branch and the stator winding branch; a processing module, configured to determine 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; A control module is used to adjust the internal potential information of the grid-connected converter based on the target potential amplitude information.

[0014] In a third aspect, the present application provides an electronic device comprising: at least one memory for storing programs; and at least one processor for executing the programs stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method described in the first aspect or any possible implementation of the first aspect.

[0015] In a fourth aspect, the present application provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method described in the first aspect or any possible implementation of the first aspect.

[0016] In a fifth aspect, the present application provides a computer program product. When the computer program product runs on a processor, the processor executes the method described in the first aspect or any possible implementation of the first aspect.

[0017] It can be understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here.

[0018] In general, the above technical solutions conceived by this application have the following beneficial effects compared with the prior art: The present application provides a virtual damping winding control method and system for a grid-forming converter. On the basis of retaining the virtual excitation loop of the existing VSG control, an additional potential loop is introduced to simulate the reactive support function of the rotor damping winding branch in a traditional synchronous machine, that is, an equivalent circuit analysis is performed on the synchronous machine with a damping winding during a transient period, and the potential amplitude information reflecting the voltage support function of the rotor damping winding is solved, and then the internal potential information of the GFM converter is dynamically adjusted in real time using the potential amplitude information. This allows the grid-forming converter to simulate the reactive support characteristics of the synchronous machine with a damping winding during a transient period, effectively improving the spontaneous reactive response capability of the GFM converter and achieving suppression of rapid fluctuations in grid voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flow chart of a virtual damping winding control method of a GFM converter provided in an embodiment of the present application; Figure 2 It is a schematic diagram of the corresponding relationship between the GFM converter using traditional virtual synchronous control and the traditional synchronous machine without damping winding; Figure 3 It is a schematic diagram of the corresponding relationship between the GFM converter with a virtual damping winding and the traditional synchronous machine with a damping winding provided in an embodiment of the present application; Figure 4 It is a schematic diagram of the main circuit topology structure of a GFM converter with a virtual damping winding provided in an embodiment of the present application; Figure 5 It is a schematic diagram of the control structure of a GFM converter with a virtual damping winding provided in an embodiment of the present application; Figure 6 (a) is a schematic diagram comparing the disturbance change of the grid connection point voltage between the control method provided in the embodiment of the present application and the traditional virtual synchronous control method, (b) is a schematic diagram comparing the disturbance change of the reactive power output by the converter between the control method provided in the embodiment of the present application and the traditional virtual synchronous control method; (c) is a schematic diagram comparing the disturbance change of the potential inside the converter between the control method provided in the embodiment of the present application and the traditional virtual synchronous control method; Figure 7 It is a structural schematic diagram of a virtual damping winding control system of a GFM converter provided in an embodiment of the present application; Figure 8 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0021] The terms "first" and "second" in the specification and claims of this application are used to distinguish different objects rather than to describe a specific order of the objects. For example, the first internal potential amplitude reference information and the second internal potential amplitude reference information are used to distinguish the internal potential amplitude reference information of the converter in different modes rather than to describe a specific order of the internal potential amplitude reference information of the converter.

[0022] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0023] In the description of the embodiments of the present application, unless otherwise specified, the meaning of "plurality" refers to two or more than two. For example, a plurality of computer instructions refers to two or more than two computer instructions, etc.

[0024] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0025] Figure 1 is a flow chart of a virtual damping winding control method for a GFM converter provided in an embodiment of the present application. The control method can be applied to a GFM converter. The equivalent circuit of a synchronous machine simulated by the GFM converter includes a stator winding branch, a rotor excitation winding branch and an armature winding branch. In addition, the equivalent circuit also includes a rotor damping winding branch, such as Figure 1 As shown, the method includes: Step S1, obtaining instantaneous voltage information at the intersection 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 GFM converter; Step S2, determining target potential amplitude information introduced by the rotor damping winding branch based on instantaneous voltage information, leakage reactance information of the rotor damping winding branch, leakage reactance information of the rotor excitation winding branch, and armature reaction reactance information of the armature winding branch; Step S3: adjusting the internal potential information of the GFM converter based on the target potential amplitude information.

[0026] Specifically, the target potential amplitude information described in the embodiment of the present application refers to the additional potential amplitude information that can reflect the voltage support effect of the rotor damping winding after the rotor damping winding branch is introduced into the synchronous machine equivalent circuit simulated by the GFM converter, which can be expressed as .

[0027] In the embodiment of the present application, on the basis of retaining the virtual excitation loop of the existing VSG control, an additional potential loop is introduced to simulate the reactive support effect of the rotor damping winding branch in the traditional synchronous machine.

[0028] Figure 2 This is a schematic diagram of the correspondence between the GFM converter using traditional virtual synchronous control and the traditional synchronous machine without damping winding, as shown in Figure 2 As shown in the figure, in the traditional virtual excitation control mode, the GFM converter only simulates the rotor excitation winding of the traditional synchronous machine, and the reactive power support capacity is equivalent to that of a synchronous machine without a damping winding. The equivalent circuit of the synchronous machine simulated by the converter includes the stator winding branch ( Branch), rotor excitation winding branch ( - branch) and armature winding branch ( branch road).

[0029] here, represents the actual filter inductance of the converter, E Indicates the reference information of the internal potential amplitude of the converter, Indicates the excitation winding flux information of the simulated synchronous machine, 、 、 They respectively 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. d Armature reaction reactance information in the axial direction; It indicates the instantaneous voltage amplitude information at the intersection of three branches during the transient period of the system (when the grid voltage suddenly changes). Indicates the instantaneous voltage amplitude information at the grid connection point during the system transient period; Indicates the grid-side line impedance, including line resistance and line reactance ; Indicates the grid-side voltage amplitude information during system transients.

[0030] The above information has the following corresponding relationship: ; .

[0031] Figure 3 Schematic diagram of the corresponding relationship between the GFM converter with a virtual damping winding and the traditional synchronous machine with a damping winding provided in the embodiment of the present application, such as Figure 3 As shown, in the embodiment of the present application, based on the existing VSG control, a rotor damping winding branch ( - Branch), as shown in the figure, there is a damping winding synchronous machine equivalent circuit during the transient period, where, Indicates the damping winding flux information of the simulated synchronous machine, It represents the leakage reactance information of the rotor damping winding branch of the simulated synchronous machine. The symbol “-” indicates series connection.

[0032] In the embodiment of the present application, the equivalent circuit of the synchronous machine is transformed into Branch and - The branch equivalent is converted to - Branch, where .

[0033] Furthermore, by equalizing the output reactive current to that of a single feeder - Branch, take ,in, It indicates the steady-state voltage amplitude information at the intersection of the four branches when the system is operating normally and steadily.

[0034] in, .

[0035] Then, in the corresponding GFM converter grid-connected circuit with virtual damping winding, the internal potential amplitude reference information of the converter becomes , converter filter reactance constant.

[0036] Here, in practical applications, the instantaneous voltage amplitude information at the intersection of each branch is measured When the converter filter reactance Divide into and The voltage amplitude information at the divided node is ,Right now Voltage amplitude information to the grid connection point The impedance between , the output internal potential at the converter bridge arm port is The impedance between . The steady-state value can be regarded as the damping winding flux of the simulated synchronous machine, that is, .

[0037] Further, continue to refer to Figure 3 In step S1, during the operation of the GFM converter, the equivalent circuit can be obtained in real time. - Branch Road, - Branch Road, Branch and Instantaneous voltage information at the branch common junction .

[0038] In the embodiment of the present application, in step S2, based on the instantaneous voltage information , - Branch leakage reactance information , - Branch leakage reactance information and Armature reaction reactance information of the branch , substituted into the preset calculation formula, the target potential amplitude information introduced by the rotor damping winding branch can be determined .

[0039] More specifically, the target potential amplitude information The calculation formula can be expressed as follows: .

[0040] More specifically, the calculation method for determining the target potential amplitude information is as follows: Determine armature reaction reactance information and leakage reactance information The first product of , and determine the armature reaction reactance information Leakage reactance information The summation result is ; Determine the second product of the summation result and the leakage reactance information of the rotor damping winding branch, and get .

[0041] The ratio of the first product to the second product With instantaneous voltage information Perform multiplication to obtain the target potential amplitude information .

[0042] Further, in the embodiment of the present application, in step S3, according to the preset control strategy, based on the target potential amplitude information Adjust the internal potential information of the GFM converter.

[0043] Figure 4 is a schematic diagram of the main circuit topology structure of a GFM converter with a virtual damping winding provided in an embodiment of the present application, such as Figure 4 As shown, in the embodiment of the present application, the GFM converter control structure specifically includes two types of control links: active-frequency loop and reactive-voltage loop, wherein the active-frequency loop control link is used to determine the phase reference information of the potential inside the GFM converter. The reactive-voltage loop control link is used to determine the amplitude reference information of the potential in the GFM converter .

[0044] Based on the content of the above embodiment, as an optional embodiment, step S3, adjusting the internal potential information of the GFM converter based on the target potential amplitude information, includes: Acquire first internal potential amplitude reference information of the GFM converter in a virtual excitation control mode; determining second internal potential amplitude reference information based on the target potential amplitude information and the first internal potential amplitude reference information; The internal potential information of the GFM converter is adjusted based on the second internal potential amplitude reference information.

[0045] Specifically, the first internal potential amplitude reference information described in the embodiment of the present application refers to the internal potential amplitude reference information of the GFM converter in the virtual excitation control mode, that is, the parameter E .

[0046] The second internal potential amplitude reference information described in the embodiment of the present application refers to the - After the branch, the internal potential amplitude reference information of the GFM converter, that is, the parameter .

[0047] In the embodiment of the present application, the first internal potential amplitude reference information is pre-calculated E， Then, the first internal potential amplitude reference information can be used E Proceed to the next step of calculation.

[0048] Based on the content of the above embodiment, as an optional embodiment, before obtaining the first internal potential amplitude reference information of the GFM converter in the virtual excitation control mode, the method further includes: Obtain output voltage amplitude information and output reactive power information of the GFM 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.

[0049] Figure 5 is a schematic diagram of a control structure of a GFM converter with a virtual damping winding provided in an embodiment of the present application, such as Figure 5 As shown, in the embodiment of the present application, in the reactive-voltage loop control link, according to obtaining the output voltage amplitude information of the GFM converter and output reactive power information , and preset reference voltage amplitude information and preset reference reactive power information , determine the first internal potential amplitude reference information E Among them, the preset reference voltage amplitude information and preset reference reactive power information All can be set according to user instructions.

[0050] Specifically, in the embodiment of the present application, the original amplitude reference signal output by the GFM converter in the virtual excitation control mode, that is, the first internal potential amplitude reference information E Satisfies the following expression: ; In the formula, Indicates reactive power-voltage droop coefficient; Represents the reactive loop integral coefficient.

[0051] Further, in an embodiment of the present application, based on the target potential amplitude information and the first internal potential amplitude reference information E , the second internal potential amplitude reference information can be determined , the calculation formula is as follows: ; That is, the improved mathematical model of the reactive power-voltage loop can be expressed as: ; Further, based on the second internal potential amplitude reference information Adjust the internal potential information of the GFM converter.

[0052] Based on the content of the above embodiment, as an optional embodiment, adjusting the internal potential information of the GFM converter based on the second internal potential amplitude reference information includes: Acquire internal potential phase reference information; the internal potential phase reference information is determined based on the output active power information of the GFM converter; determining target internal potential reference information based on the second internal potential amplitude reference information and the internal potential phase reference information; generating a target PWM modulation signal based on target internal potential reference information; Based on the target PWM modulation signal, the switch tube of the GFM converter is controlled to operate to the target switch tube state, so that the GFM converter generates internal potential information under the target switch tube state.

[0053] Specifically, in the embodiment of the present application, in the implementation method of adjusting the internal potential information of the GFM converter, firstly, the internal potential phase reference information is obtained. .

[0054] Continue to refer to Figure 5 In an embodiment of the present application, before obtaining the internal potential phase reference information, the method further includes: Obtain output active power information of GFM 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.

[0055] Specifically, in the embodiment of the present application, in the active-frequency loop control link, according to obtaining the output active power information of the GFM converter , and preset converter reference angular velocity information and preset reference active power information , determine the phase reference information of the potential inside the GFM converter Among them, the preset converter reference angular velocity information and preset reference active power information All can be set according to user instructions.

[0056] More specifically, in an embodiment of the present application, the internal potential phase reference information It can be solved by the following mathematical model of active power-frequency loop, namely: ; In the formula, represents the angular velocity of the converter, represents the system damping coefficient; J Represents the system virtual inertia.

[0057] Further, continue to refer to Figure 4 , based on the internal potential amplitude reference information of the converter and internal potential phase reference information , by determining the target internal potential reference information, the complete parameter information that the internal potential of the converter needs to meet can be obtained.

[0058] Furthermore, by using the PWM modulation method, the target internal potential reference information calculated above is used to generate a target PWM modulation signal, and then the target PWM modulation signal can be used to control the switch tube of the GFM converter to operate to the target switch tube state, and the GFM converter generates internal potential information under the target switch tube state, thereby realizing real-time dynamic adjustment of the internal potential information of the GFM converter.

[0059] In the embodiment of the present application, during the normal steady-state operation of the GFM converter, the potential amplitude in the converter satisfies ,in is the instantaneous voltage amplitude information at each branch intersection The steady-state value of for In the dynamic process of grid voltage sudden drop / surge, due to the output in virtual excitation control mode, E remains unchanged, so the potential inside the converter during the voltage jump satisfy: ; It can be seen that That is, in the dynamic process The change is negative when there is a sudden drop and positive when there is a sudden increase, which can effectively suppress the rapid fluctuation of the grid voltage.

[0061] Among them, the change of internal potential That is the role of the virtual damping winding in reactive support.

[0062] For example, taking the grid voltage sudden drop condition as an example, at this time, the internal potential amplitude of the GFM converter can suddenly increase, and the sudden increase is: , while the potential amplitude of the converter with the existing grid-type control strategy can only remain unchanged at the moment of voltage drop. Therefore, the virtual damping winding control method provided in the embodiment of the present application can make the converter's spontaneous reactive power support capability stronger than that of the converter with the existing grid-type control strategy.

[0063] The virtual damping winding control method of the GFM converter of the embodiment of the present application introduces an additional potential loop to simulate the reactive support function of the rotor damping winding branch in the traditional synchronous machine on the basis of retaining the virtual excitation loop of the existing VSG control, that is, an equivalent circuit analysis is performed on the synchronous machine with the damping winding during the transient period, and the potential amplitude information reflecting the voltage support function of the rotor damping winding is solved, and then the internal potential information of the GFM converter is dynamically adjusted in real time using the potential amplitude information, so that the grid-type converter can simulate the reactive support characteristics of the synchronous machine with the damping winding during the transient period, effectively improve the spontaneous reactive response capability of the GFM converter, and realize the suppression of rapid fluctuations in the grid voltage.

[0064] In a specific embodiment of the present application, in order to verify the effectiveness of the virtual damping winding control method of the GFM converter of the embodiment of the present 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.

[0065] Table 1

[0066] Table 2

[0067] Build in Matlab / Simulink simulation platform Figure 4 For the circuit model shown, the simulation conditions are: t =5s, 0.5pu reactive load is put into the grid connection point, and the load is cut out after 100ms to simulate the rapid voltage fluctuation event in the system.

[0068] The results of the GFM converter without and with the virtual damping winding control method provided in the embodiment of the present application are compared. Figure 6 shown.

[0069] Figure 6 (a) is a schematic diagram comparing the disturbance change of the grid connection point voltage between the control method provided in the embodiment of the present application and the traditional virtual synchronous control method, (b) is a schematic diagram comparing the disturbance change of the converter output reactive power between the control method provided in the embodiment of the present application and the traditional virtual synchronous control method; (c) is a schematic diagram comparing the disturbance change of the converter internal potential between the control method provided in the embodiment of the present application and the traditional virtual synchronous control method, as shown in FIG. Figure 6 As shown in (a), the voltage amplitude of the grid connection point drops greatly under the traditional virtual synchronous control, while the lowest point of the voltage amplitude and the rate of change of the grid connection point are significantly improved under the control of the virtual damping winding provided by the embodiment of the present application. like Figure 6 As shown in (b), under the traditional virtual synchronous control, the spontaneous reactive response of the converter after the disturbance occurs is small, while under the virtual damping winding control provided by the embodiment of the present application, the converter generates a stronger spontaneous reactive response to support the grid voltage stability after the grid connection point is lowered. like Figure 6 As shown in (c), under the traditional virtual synchronous control, the internal potential of the bridge arm output of the converter can only remain unchanged instantly after the disturbance occurs. However, under the virtual damping winding control provided by the embodiment of the present application, the internal potential of the bridge arm output of the converter can spontaneously increase instantly after the disturbance occurs, thereby achieving a stronger voltage support effect.

[0070] The virtual damping winding control system of the GFM converter provided in the present application is described below. The virtual damping winding control system of the GFM converter described below and the virtual damping winding control method of the GFM converter described above can be referred to each other.

[0071] Figure 7 is a structural schematic diagram of a virtual damping winding control system of a GFM converter provided in an embodiment of the present application. The system can be applied to a GFM converter. The equivalent circuit of a synchronous machine simulated by the GFM 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. Figure 7 As shown, the system includes: An acquisition module 10 is used to acquire instantaneous voltage information at a common intersection of a rotor damping winding branch, a rotor excitation winding branch, an armature winding branch and a stator winding branch of a synchronous machine simulated by a GFM converter; 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; The control module 30 is used to adjust the internal potential information of the GFM converter based on the target potential amplitude information.

[0072] It can be understood that the detailed functional implementation of each of the above-mentioned units / modules can be found in the introduction of the aforementioned method embodiment, and will not be repeated here.

[0073] It should be understood that the above-mentioned device is used to execute the method in the above-mentioned embodiment. The implementation principle and technical effect of the corresponding program module in the device are similar to those described in the above-mentioned method. The working process of the device can refer to the corresponding process in the above-mentioned method, which will not be repeated here.

[0074] The virtual damping winding control system of the GFM converter of the embodiment of the present application introduces an additional potential loop to simulate the reactive support function of the rotor damping winding branch in the traditional synchronous machine on the basis of retaining the virtual excitation loop of the existing VSG control, that is, an equivalent circuit analysis is performed on the synchronous machine with the damping winding during the transient period, and the potential amplitude information reflecting the voltage support function of the rotor damping winding is solved, and then the internal potential information of the GFM converter is adjusted dynamically in real time using the potential amplitude information, so that the grid-type converter can simulate the reactive support characteristics of the synchronous machine with the damping winding during the transient period, effectively improve the spontaneous reactive response capability of the GFM converter, and realize the suppression of rapid fluctuations in the grid voltage.

[0075] Based on the method in the above embodiment, the embodiment of the present application provides an electronic device, such as Figure 8As shown, the electronic device may include: a processor (Processor) 810, a communication interface (Communications Interface) 820, a memory (Memory) 830 and a communication bus 840, wherein the processor 810, the communication interface 820, and the memory 830 communicate with each other through the communication bus 840. The processor 810 can call the logic instructions in the memory 830 to execute the method in the above embodiment.

[0076] In addition, the logic instructions in the above-mentioned memory 830 can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application.

[0077] Based on the method in the above embodiment, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method in the above embodiment.

[0078] Based on the method in the above embodiment, an embodiment of the present application provides a computer program product. When the computer program product runs on a processor, the processor executes the method in the above embodiment.

[0079] It is understandable that the processor in the embodiment of the present application may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0080] The method steps in the embodiments of the present application can be implemented by hardware or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules 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, mobile hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium 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 be located in an ASIC.

[0081] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of 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, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted through the computer-readable storage medium. The computer instructions may be transmitted from a website site, computer, server or data center to another website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)), etc.

[0082] It should be understood that the various numerical numbers involved in the embodiments of the present application are only used for the convenience of description and are not used to limit the scope of the embodiments of the present application.

[0083] It should be understood that expressions such as "including" and "may include" that may be used in the present 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 the present application, terms such as "including" and / or "having" may be interpreted as indicating specific characteristics, numbers, operations, constituent elements, components, or combinations thereof, but may not be interpreted as excluding the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0084] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application shall be included in the scope of protection of the present 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 a synchronous machine simulated by the grid-type converter comprises a stator winding branch, a rotor excitation winding branch and an armature winding branch, and is characterized in that: The equivalent circuit further includes a rotor damping winding branch, and the method includes: Acquire instantaneous voltage information at a common intersection of a rotor damping winding branch, a rotor excitation winding branch, an armature winding branch and a stator winding branch of a synchronous machine simulated by the grid-type converter; Determining 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 internal potential information of the grid-connected converter is adjusted based on the target potential amplitude information.

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

3. The virtual damping winding control method of a grid-connected converter according to claim 2, characterized in that: The adjusting the internal potential information of the grid-connected converter based on the second internal potential amplitude reference information includes: Acquiring 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; determining target internal potential reference information based on the second internal potential amplitude reference information and the internal potential phase reference information; generating a target PWM modulation signal based on the target internal potential reference information; Based on the target PWM modulation signal, the switch tube of the grid-type converter is controlled to operate to a target switch tube state, so that the grid-type converter generates internal potential information under the target switch tube state.

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

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

6. The virtual damping winding control method of a grid-connected converter according to any one of claims 1 to 5, characterized in that: 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 comprises: Determine a first product of the armature reaction reactance information and the leakage reactance information of the rotor excitation winding branch, and determine a summation result of the armature reaction reactance information and the leakage reactance information of the rotor excitation winding branch; Determine a second product of the summation result and the leakage reactance information of the rotor damping winding branch; The target potential amplitude information is obtained by multiplying the ratio of the first product to the second product by the instantaneous voltage information.

7. A virtual damping winding control system for a grid-type converter, applied to a grid-type converter, wherein the equivalent circuit of a synchronous machine simulated by the grid-type converter comprises a stator winding branch, a rotor excitation winding branch and an armature winding branch, and is characterized in that: The equivalent circuit further includes a rotor damping winding branch, and the system includes: An acquisition module, used to acquire instantaneous voltage information at a common intersection of the rotor damping winding branch, the rotor excitation winding branch, the armature winding branch and the stator winding branch; a processing module, configured to determine 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; A control module is used to adjust the internal potential information of the grid-connected converter based on the target potential amplitude information.

8. An electronic device, characterized in that: include: at least one memory for storing a computer program; At least one processor is used to execute the program stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method according to any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program runs on a processor, the processor is caused to execute the method according to any one of claims 1 to 6.

10. A computer program product, characterized in that When the computer program product runs on a processor, the processor is caused to execute the method according to any one of claims 1 to 6.

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