Power oscillation suppression method, system, controller and storage medium

Abstract

The present application discloses a power oscillation suppression method, system, controller and storage medium. The method comprises obtaining a voltage signal u of a power system. abc , and the voltage signal u abc Converted into the voltage signal u of the two-phase coordinate system dq . The voltage signal u dq After processing, the #imgabs0# signal of the oscillation frequency is obtained, and the #imgabs1# signal is subjected to phase correction and gain to be superimposed on the #imgabs2# signal to form a dq axis current instruction; determine whether the oscillation amplitude of the #imgabs3# signal decreases; if the oscillation amplitude of the #imgabs4# signal decreases, adjust the angle and gain of the phase correction; if the oscillation amplitude of the #imgabs5# signal does not decrease, adjust the angle and gain of the phase correction in the opposite direction, and finally find a set of parameters that can minimize the oscillation amplitude of the #imgabs6# signal. Using the embodiments of the present application, the power converter can be optimized through the control algorithm, can intelligently adjust its own output impedance, and can effectively suppress the power oscillation of the power system.

Description

Technical Field

[0001] The present application relates to the field of power electronics and new energy power generation technology, and in particular to a power oscillation suppression method, system, controller and storage medium. Background Art

[0002] As the energy crisis and environmental pollution problems become increasingly prominent around the world, renewable energy generation represented by photovoltaic power generation, wind power generation and hydropower generation is developing rapidly and will occupy an important position in the future energy composition. With the widespread application of new energy power electronic equipment in power systems, stability problems such as low-frequency oscillation and subsynchronous oscillation in power systems are becoming more and more serious.

[0003] At present, the traditional power system adopts the method of installing a power system stabilizer (PSS) on a synchronous generator to provide the power oscillation damping (POD) capability. However, the above method is limited by the physical characteristics of the synchronous generator and cannot effectively suppress the wide-band oscillation phenomenon. In addition, the effect of the device is closely related to the local power grid structure and surrounding electrical equipment, making it difficult to debug the equipment. At the same time, the effect will also change with the actual working conditions.

[0004] Therefore, it is necessary to find a universal power oscillation suppression solution. When power oscillation occurs in the power system, new energy power electronic equipment can optimize the control algorithm and intelligently adjust its own output impedance to suppress the power oscillation of the power system without the need for debugging for specific scenarios. Summary of the invention

[0005] The embodiments of the present application provide a power oscillation suppression method, system, controller and storage medium. When power oscillation occurs in the power system, the power converter can be optimized through a control algorithm and can intelligently adjust its own output impedance, thereby effectively suppressing the power oscillation of the power system.

[0006] In a first aspect, an embodiment of the present application provides a power oscillation suppression method, which is applied to a power system. The method comprises: obtaining a voltage signal u of the power system abc , and the voltage signal u abc Converted into the voltage signal u of the two-phase coordinate system dq , and extract the oscillation frequency oh os c . The voltage signal u dq After the filter processing, the oscillation frequency is obtained Signal, will After the phase correction link and the proportional link to adjust the phase and gain, it is then added to The signal forms a new dq axis current command and is sent to the current loop for control; the phase correction angle and gain are adjusted, and the The change of the oscillation amplitude of the signal, if the oscillation amplitude decreases, adjust it in the same phase and gain adjustment direction; if the oscillation amplitude remains unchanged, stop parameter adjustment and maintain the current parameters unchanged; if the oscillation amplitude increases, adjust the phase correction angle and gain in the opposite direction.

[0007] By adopting the embodiments of the present application, when power oscillation occurs in the power system, the power converter can be optimized through the control algorithm and can intelligently adjust its own output impedance, thereby effectively suppressing the power oscillation of the power system.

[0008] In one possible design, the method further includes: abc Perform fast Fourier transform analysis to obtain the oscillation frequency and oscillation amplitude of the power system. Through Fourier analysis of the voltage signal, the oscillation frequency and oscillation amplitude of the power system can be obtained, and then the output impedance can be intelligently adjusted through control algorithm optimization.

[0009] In one possible design, the method further includes: determining whether the oscillation amplitude is greater than or equal to a first threshold; if the oscillation amplitude is greater than or equal to the first threshold, controlling the power oscillation suppression system to enter an impedance adjustment mode. Based on such a design, the embodiment of the present application can control whether the power oscillation suppression system enters an impedance adjustment mode by determining the relationship between the oscillation amplitude and the first threshold, thereby suppressing power oscillations of the power system.

[0010] In a possible design, after adjusting the phase correction angle and gain, it also includes: determining whether the oscillation amplitude is less than or equal to a second threshold; if the oscillation amplitude is less than or equal to the second threshold, gradually reducing the loop gain of the additional signal, and gradually removing the superimposed dq axis current command to restore the normal working state of the power oscillation suppression system. The embodiment of the present application can restore the normal working state of the power oscillation suppression system according to the judgment result by determining whether the oscillation amplitude is less than or equal to the second threshold.

[0011] In one possible design, the method further includes: obtaining an oscillation frequency provided by a power grid company and an oscillation amplitude to be suppressed.

[0012] In one possible design, the method further includes: if the power grid company requires the power converter to provide a power oscillation suppression function, continuing to adjust the phase correction angle and gain according to the above adjustment method.

[0013] In one possible design, after adjusting the phase correction angle and gain, it also includes: determining whether the power grid company needs to provide a power oscillation suppression function; if the power grid company does not need to provide a power oscillation suppression function, removing the superimposed dq-axis current instructions to restore the normal working state of the power oscillation suppression system.

[0014] In a second aspect, an embodiment of the present application also provides a controller electrically connected to a power converter for controlling the switching state in the power converter, the controller comprising: a memory for storing a computer program; a processor for executing the computer program stored in the memory, when the computer program is executed, the processor is used to execute the power oscillation suppression method as described above.

[0015] In a third aspect, an embodiment of the present application further provides a storage medium, wherein the storage medium includes computer instructions. When the computer instructions are executed on a controller, the controller executes the power oscillation suppression method as described above.

[0016] In a fourth aspect, an embodiment of the present application also provides a power oscillation suppression system, which includes a power converter and a controller as described above; the controller is electrically connected to the power converter, and the controller is used to control the switching state in the power converter.

[0017] The power oscillation suppression method, system, controller and storage medium provided in the embodiments of the present application. Using the embodiments of the present application, when power oscillation occurs in the power system, the power converter can be optimized through the control algorithm, and its output impedance can be intelligently adjusted, thereby effectively suppressing the power oscillation of the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the application environment of the power oscillation suppression system according to an embodiment of the present application.

[0019] Figure 2 Schematic diagram of the structure of the power oscillation suppression system according to an embodiment of the present application.

[0020] Figure 3 Flow chart of a power oscillation suppression method according to an embodiment of the present application.

[0021] Figure 4 It is a simulation diagram of the power oscillation suppression system according to an embodiment of the present application.

[0022] Figure 5 This is another application simulation diagram of the power oscillation suppression system provided in the embodiment of the present application.

[0023] Figure 6This is an application simulation diagram of the power oscillation suppression device provided in an embodiment of the present application.

[0024] Figure 7 A schematic diagram of the structure of a controller according to an embodiment of the present application.

[0025] Main component symbols

[0026] Power Oscillation Suppression System 100

[0027] Power System 200

[0028] Grid 210

[0029] Filter circuit 30

[0030] Transformer 230

[0031] Controller 10

[0032] Memory 101

[0033] Processor 102

[0034] Voltage and current acquisition module 12

[0035] Phase-locked loop module 14

[0036] Processing module 16

[0037] Three-phase coordinate system and two-phase coordinate system conversion unit 161, 162

[0038] Bandpass filter 163

[0039] Phase correction unit 164

[0040] Gain unit 165

[0041] Analysis Unit 166

[0042] Current adjustment unit 167

[0043] Two-phase coordinate system and three-phase coordinate system conversion unit 168

[0044] Pulse Width Modulation Unit 169

[0045] Power converter 20

[0046] Power control unit 40

[0047] Inductor L1, Lg

[0048] The following specific implementation methods will further illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0050] It should be noted that when an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be a centrally disposed element at the same time. When an element is considered to be "disposed on" another element, it may be directly disposed on the other element or there may be a centrally disposed element at the same time.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0052] See also Figure 1 , Figure 1 The block diagram of a power oscillation suppression system 100 provided by an embodiment of the present application is shown. The power oscillation suppression system 100 in this embodiment can be electrically connected to a power system 200, and the power oscillation suppression system 100 can change the output impedance of the power electronic device according to the grid demand, thereby suppressing the power oscillation in the power system 200.

[0053] In a possible application scenario, Figure 1 As shown, the power system 200 may include a power grid 210, an inductor Lg, and a transformer 230. The power grid 210 may be electrically connected to the inductor Lg, the inductor Lg may be electrically connected to the transformer 230, and the transformer 230 may be electrically connected to the power oscillation suppression system 100. It can be understood that the two ends of the inductor Lg are electrically connected to the power grid 210 and the transformer 230, respectively. It can be understood that the power oscillation suppression system 100 can be used as a power electronic device to output power to the power system 200.

[0054] In one embodiment, the transformer 230 is used to receive the power output by the power oscillation suppression system 100, convert the voltage of the power, and transmit the converted power to the power grid 210. Thus, the power grid 210 can supply power to the load.

[0055] It can be understood that the power oscillation suppression system 100 in the embodiment of the present application may include a controller 10 , a power converter 20 and a filter circuit 30 .

[0056] Specifically in the implementation process of the present application, the controller 10 can be coupled to the power converter 20, and the filter circuit 30 can be coupled between the power converter 20 and the transformer 230. The controller 10 can be coupled to the node between the transformer 230 and the filter circuit 30. It can be understood that the filter circuit 30 in this embodiment can include an inductor L1, one end of the inductor L1 can be coupled to the power converter 20, and the other end of the inductor L1 can be electrically connected to the controller 10 and the transformer 230. It can be understood that in one embodiment, the controller 10 can be used to collect the working parameters of the power system 200. For example, in a specific scenario, the controller 10 can collect electrical quantities such as voltage and current of the power system 200. Therefore, the controller 10 can analyze and process according to the collected parameters to obtain a control signal for controlling the on and off of the switch in the power converter 20.

[0057] See also Figure 2 The power oscillation suppression system 100 provided in the embodiment of the present application will be described below with reference to the accompanying drawings and actual application scenarios.

[0058] Figure 2 1 is a schematic diagram of a controller disclosed in an embodiment of the present application. The controller 10 can be used to execute Figure 3 or Figure 6 For details, please refer to the power oscillation suppression method described in part or all of the steps. Figure 3 or Figure 6 The relevant description in will not be repeated here.

[0059] In the embodiment of the present application, the controller 10 may include a voltage and current acquisition module 12 , a phase-locked loop module 14 and a processing module 16 .

[0060] The voltage and current acquisition module 12 is used to acquire the operating parameters of the power system 200. For example, the voltage and current acquisition module 12 can acquire the voltage and current of the power grid 210. In one embodiment, the voltage and current acquisition module 12 can acquire the current and voltage output by the power system 200.

[0061] In this embodiment, the voltage and current acquisition module 12 can transmit the collected voltage and current of the power grid 210 to the processing module 16, and the processing module 16 can perform fast Fourier transform (FFT) analysis on the voltage and current to obtain the oscillation frequency and oscillation component amplitude of the power system 200.

[0062] It can be understood that in some possible implementations, the oscillation frequency and the oscillation component amplitude can also be obtained by sampling other node data or provided by a power grid company.

[0063] The phase-locked loop module 14 may be used to extract the phase angle of the voltage output by the filter circuit 30 , and transmit the extracted phase angle to the processing module 16 .

[0064] It can be understood that in a possible embodiment, the processing module 16 may include a three-phase coordinate system and two-phase coordinate system conversion unit 161, a three-phase coordinate system and two-phase coordinate system conversion unit 162, a bandpass filter 163, a phase correction unit 164, a gain unit 165, an analysis unit 166, a current adjustment unit 167, a two-phase coordinate system and three-phase coordinate system conversion unit 168, and a pulse width modulation unit 169.

[0065] The analysis unit 166 may perform a fast Fourier transform analysis on the voltage and current collected by the voltage and current collection module 12 to obtain the oscillation frequency and oscillation component amplitude of the power system 200 .

[0066] The three-phase coordinate system and two-phase coordinate system conversion unit 161 can be used to convert the collected voltage signal u abc Convert the three-phase coordinate system to the two-phase coordinate system to obtain the voltage signal u of the two-phase coordinate system dq .

[0067] The bandpass filter 163 can be used to dq Filtering is performed to obtain the oscillation frequency Signal. Oscillation frequency The signal can be a voltage signal u dq The signal retained at the oscillation frequency. It is understood that in one embodiment, the Signals can include Signal and Signal.

[0068] The phase correction unit 164 and the gain unit 165 are respectively Signal and The signal is phase corrected and amplified to add to and The phase correction unit 164 is used to correct the Signal and The signal is phase corrected and the phase corrected Signal and The signal is transmitted to the gain unit 165, and the gain unit 165 can adjust the phase-corrected u d osc Signal and The signal is amplified to output Signal. The signal is output according to the power control unit 40. The signals are superimposed to obtain Signal.

[0069] The three-phase coordinate system and two-phase coordinate system conversion unit 162 can be used to convert the collected current i abc Convert the three-phase coordinate system to the two-phase coordinate system to obtain the current i in the two-phase coordinate system dq .

[0070] The current adjustment unit 167 can adjust the current signal i dq and current command signal, forming the dq axis modulation voltage command e dq .

[0071] The two-phase coordinate system and three-phase coordinate system conversion unit 168 can be used to convert the modulation voltage instruction e dq Convert the current command e into the three-phase coordinate system abc The pulse width modulation unit 169 is based on the current instruction e abc The control signal for controlling the on and off of the switch in the power converter 20 is output.

[0072] The embodiments of the present application can achieve the best tracking of the power oscillation suppression effect, and further can achieve the goal of providing the power oscillation suppression function with maximum capability by the power electronic equipment according to the adaptive grid conditions.

[0073] It is to be understood that the division of the modules in the controller 10 is only for illustration. In other embodiments, the controller 10 may be divided into different modules as needed to complete all or part of the functions of the controller 10. The implementation of the modules in the controller 10 provided in the embodiment of the present application may be in the form of a computer program. The specific implementation of the modules in the embodiment of the present application may also correspond to the reference Figure 3 or Figure 6 The corresponding description of the method embodiment shown in the figure. For specific contents, please refer to the specific embodiment of the power oscillation suppression method described below, which will not be described in detail here.

[0074] See also Figure 3 , which is a flow chart of a power oscillation suppression method provided in an embodiment of the present application. The power oscillation suppression method of this embodiment can be applied to control Figure 1 as well as Figure 2 The power oscillation suppression system 100 shown. The power oscillation suppression method of this embodiment may include the following steps:

[0075] Step S31, obtaining the oscillation frequency and oscillation amplitude of the power system.

[0076] It can be understood that in the embodiment of the present application, the power oscillation suppression system 100 can obtain the operating parameters of the power grid 210. For example, the voltage and current acquisition module 12 in the power oscillation suppression system 100 can acquire parameter data such as the voltage and current of the power grid 210. The voltage and current acquisition module 12 can acquire the current and voltage output by the power system 200.

[0077] The processing module 16 in the power oscillation suppression system 100 can also perform fast Fourier transform analysis on the collected voltage and current. Based on such a design, the power oscillation suppression system 100 can obtain the oscillation frequency and oscillation component amplitude of the power system 200.

[0078] It can be understood that in some other possible implementations, the frequency and amplitude of the oscillation component can also be obtained by sampling data from other nodes or provided by a power grid company.

[0079] Step S32, determining whether the oscillation amplitude is greater than or equal to a first threshold value. If the oscillation amplitude is greater than or equal to the first threshold value, proceed to step S33, otherwise, proceed to step S32 again.

[0080] In this embodiment, after acquiring the oscillation frequency and the amplitude of the oscillation component in the power system 200 , the processing module 16 may further determine whether the amplitude of the oscillation component is greater than or equal to a first threshold.

[0081] Step S33: the power oscillation suppression system enters an impedance adjustment mode.

[0082] If the amplitude of the oscillation component is greater than the first threshold, the power oscillation suppression system 100 enters an impedance adjustment mode.

[0083] Specifically, when the amplitude of the oscillation component is greater than the first threshold, the processing module 16 can be used to collect the voltage u abc Convert the three-phase coordinate system to the two-phase coordinate system to obtain the voltage signal u of the two-phase coordinate system dq .

[0084] The bandpass filter 163 can be used to dq Filtering is performed to obtain the oscillation frequency signal. Among them, the oscillation frequency The signal can be a voltage signal u dq The signal retained at the oscillation frequency. It can be understood that Signals can include Signal and Signal.

[0085] Step S34: dq The signal is processed by a filter to obtain the oscillation frequency. signal, u dq Signal phase correction and gain to add to i dq ref The signals form new dq axis current instructions.

[0086] Specifically, the phase correction unit 164 performs Signal and The signal is phase corrected and the phase corrected Signal and The signal is transmitted to the gain unit 165, and the gain unit 165 performs the phase correction on the Signal and The signal is amplified to output Signal. The signal is output according to the power control unit 40. The signals are superimposed to obtain Signal.

[0087] It can be understood that in one embodiment, the Signals can include Signal and Based on this design, the phase correction unit 164 and the gain unit 165 can respectively Signal and The signal is phase corrected and amplified to add to Thus, the dq axis modulation voltage command e can be formed by the current adjustment unit 167. dq .

[0088] In some possible implementations, the power converter 20 may operate in a normal operating mode of maximum power point tracking or power scheduling, or may operate in a current control mode of a given current command.

[0089] Step S35, adjusting the angle and gain of phase correction.

[0090] In this embodiment, the processing module 16 can adjust the filter parameters to adjust the angle and gain of the phase correction. Specifically, the processing module 16 can adjust the phase angle first, and then adjust the gain.

[0091] Step S36, determining whether the oscillation amplitude decreases. If the oscillation amplitude decreases, return to step S35, otherwise proceed to step S37.

[0092] The processing module 16 can also detect the attenuation degree of the oscillation component. Thus, the processing module 16 can determine whether the oscillation component increases or decreases after the parameter modification according to the attenuation degree of the oscillation component.

[0093] For example, if the oscillation component decreases, the processing module 16 changes the parameters in the same direction, that is, adjusts the angle and gain of the phase correction in the same direction.

[0094] Step S37, adjusting the phase correction angle and gain in the opposite direction.

[0095] It can be understood that if the oscillation component increases, the processing module 16 changes the parameters in the opposite direction, that is, adjusts the angle and gain of the phase correction in the opposite direction.

[0096] Step S38, determining whether the oscillation amplitude is less than or equal to a second threshold value. If the oscillation amplitude is less than or equal to the second threshold value, proceed to step S39, otherwise return to step S37.

[0097] In this embodiment, when adjusting the phase correction angle and gain in opposite directions, the processing module 16 will also compare the oscillation amplitudes.

[0098] It can be understood that, due to the limitations of factors such as the grid operation condition and sampling accuracy, the oscillation component will fluctuate within a range around the minimum value that can be achieved, thereby achieving tracking with the best power oscillation suppression effect.

[0099] Step S39, gradually reducing the loop gain of the additional signal, gradually removing the additional dq axis current instructions, and restoring the normal working state of the power oscillation suppression system.

[0100] It can be understood that in the embodiment of the present application, when the power oscillation of the power grid 210 disappears, that is, the oscillation amplitude is less than or equal to the second threshold, or the power grid company issues an instruction to the new energy power station not to participate in power oscillation suppression, the power oscillation suppression system will exit the impedance adjustment mode and return to normal working state.

[0101] like Figure 4 and Figure 5As shown, by adopting the power oscillation suppression method of the embodiment of the present application, the output impedance of the power electronic device can be changed according to the actual grid scenario and demand, and the function of suppressing the power oscillation of the power system can be realized. Furthermore, the embodiment of the present application overcomes the problem of needing to debug according to the local grid conditions and equipment operating conditions. The power oscillation suppression method in the embodiment of the present application is a universal control method for suppressing grid power oscillation, which can avoid the obstacle of not being able to exert the maximum capacity of the power electronic device due to the construction of a fixed virtual impedance. At the same time, the technical solution of the embodiment of the present application does not need to detect and identify the grid impedance, and is practical.

[0102] See also Figure 6 , which is a flow chart of a power oscillation suppression method provided by another embodiment of the present application. The power oscillation suppression method of this embodiment can be applied to control Figure 1 as well as Figure 2 The power oscillation suppression system 100 shown. The power oscillation suppression method of this embodiment may include the following steps:

[0103] Step S61, obtaining the oscillation frequency provided by the power grid company and the oscillation amplitude to be suppressed.

[0104] Understandably, Figure 6 The embodiment of the power oscillation suppression method shown is Figure 3 The difference between the illustrated embodiment of the power oscillation suppression method is that, in this embodiment, the oscillation frequency and the oscillation amplitude to be suppressed are provided by the power grid company.

[0105] Step S62: the power oscillation suppression system enters an impedance adjustment mode.

[0106] Step S63: dq The signal is processed by a filter to obtain the oscillation frequency. signal, u dq After phase correction and gain, it is superimposed on Form new dq axis current instructions.

[0107] It can be understood that in one embodiment, the Signals can include Signal and Based on this design, the phase correction unit 164 and the gain unit 165 can respectively Signal and The signal is phase corrected and amplified to add to Signal and Thus, a new dq axis current command can be formed by the current adjustment unit 167.

[0108] In some possible implementations, the power converter 20 may operate in a normal operating mode of maximum power point tracking or power scheduling, or may operate in a current control mode of a given current command.

[0109] Step S64, adjusting the angle and gain of phase correction.

[0110] In this embodiment, the processing module 16 can adjust the filter parameters to adjust the angle and gain of the phase correction. Specifically, the processing module 16 can adjust the phase angle first, and then adjust the gain.

[0111] Step S65, determining whether the oscillation amplitude decreases. If the oscillation amplitude decreases, the process returns to step S35, otherwise, the process proceeds to step S66.

[0112] Step S66, adjusting the phase correction angle and gain in the opposite direction.

[0113] It can be understood that if the oscillation component increases, the processing module 16 changes the parameters in the opposite direction, that is, adjusts the angle and gain of the phase correction in the opposite direction.

[0114] Step S67, determine whether the power grid company still needs to provide POD capabilities. If yes, return to step S66, otherwise go to step S68.

[0115] Step S68, removing the additional dq-axis current instructions and restoring the normal working state of the power oscillation suppression system.

[0116] The power oscillation suppression method proposed in this application can exit the impedance adjustment mode and resume normal working state if the power oscillation suppression system does not need to provide POD capability. By adopting the embodiments of this application, it can be realized that the power electronic equipment can be optimized through the control algorithm, intelligently adjust its own output impedance, and actively suppress the power oscillation of the power system without debugging for specific scenarios, thereby improving the stability of system operation and saving system costs.

[0117] See also Figure 7 FIG. 1 is another schematic diagram of the structure of the controller 10 provided in an embodiment of the present application. In one embodiment, the controller 10 includes a memory 101 and at least one processor 102. Those skilled in the art should understand that Figure 7 The structure of the controller 10 shown does not constitute a limitation of the embodiments of the present application. The controller 10 may also include more or less other hardware or software than shown in the figure, or a different component arrangement.

[0118] In some embodiments, the controller 10 includes a terminal that can automatically perform numerical calculations and / or information processing according to pre-set or stored instructions, and its hardware includes but is not limited to a microprocessor, an application-specific integrated circuit, a programmable gate array, a digital processor, and an embedded device. In some embodiments, the memory 101 is used to store program codes and various data. The memory 101 may include a read-only memory (ROM), a random access memory (RAM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), a one-time programmable read-only memory (OTPROM), an electronically erasable rewritable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, magnetic disk storage, magnetic tape storage, or any other computer-readable medium that can be used to carry or store data.

[0119] In some embodiments, the at least one processor 102 may include an integrated circuit, for example, a single packaged integrated circuit, or a plurality of integrated circuits with the same or different functions, including a combination of a microprocessor, a digital processing chip, a graphics processor, and various control chips, etc. The at least one processor 102 is the control core (Control Unit) of the controller, and executes or executes the program or module stored in the memory 101, and calls the data stored in the memory 101 to execute various functions of the controller 10 and process data, such as executing the control function of the resonant power supply.

[0120] The above-mentioned integrated unit implemented in the form of a software function module can be stored in a computer-readable storage medium. The above-mentioned software function module is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, terminal, or network device, etc.) or a processor to execute part of the method described in each embodiment of the present application.

[0121] The memory 101 stores program codes, and the at least one processor 102 can call the program codes stored in the memory 101 to execute related functions. In one embodiment of the present application, the memory 101 stores multiple instructions, and the multiple instructions are executed by the at least one processor 102 to implement the power oscillation suppression method. Specifically, the specific implementation method of the at least one processor 102 for the above instructions can refer to Figure 3 or Figure 6 The description of the relevant steps in the corresponding embodiments will not be repeated here.

[0122] By using the power oscillation suppression system and suppression method in the embodiments of the present application, it is possible to achieve optimal tracking of the power oscillation suppression effect, and it is possible to enable power electronic equipment to provide power oscillation suppression function with maximum capacity according to adaptive grid conditions, thereby improving system operation stability.

[0123] The embodiment of the present application further provides a storage medium, wherein the storage medium stores computer instructions, and when the instructions are executed on a computing device, the computing device executes the power oscillation suppression method provided in the above embodiment.

[0124] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present application and are not intended to be limiting of the present application. As long as they are within the spirit and scope of the present application, appropriate changes and modifications to the above embodiments are within the scope of protection claimed in the present application.

Claims

1. A power oscillation suppression method, applied to a power oscillation suppression system, characterized in that: The method comprises: Obtain the oscillation frequency and oscillation amplitude of the power system; When the first condition is met, the voltage signal u of the power system abc Converted into the voltage signal u of the two-phase coordinate system dq ; The first condition includes that the oscillation amplitude is greater than or equal to a first threshold; The voltage signal u dq After the filter processing, the oscillation frequency is obtained signal, the The signal is phase corrected and amplified to adjust the phase and gain and then added to The signal forms the dq axis current command; Based on the The signal is phase corrected and gain adjusted to adjust the phase and gain, and the detection is performed. The change of the oscillation amplitude of the signal; if the u dq osc If the oscillation amplitude of the signal decreases, the phase correction angle and gain are adjusted to adjust the output impedance of the power converter; if the If the oscillation amplitude of the signal remains unchanged, stop adjusting the parameters; if the The oscillation amplitude of the signal increases, and the phase correction angle and gain are adjusted inversely to adjust the output impedance of the power converter.

2. The power oscillation suppression method according to claim 1, characterized in that: The obtaining of the oscillation frequency and oscillation amplitude of the power system comprises: Get the voltage signal u of the power system abc ; For the voltage signal u abc Fast Fourier transform analysis is performed to obtain the oscillation frequency and oscillation amplitude of the power system.

3. The power oscillation suppression method according to claim 1 or 2, characterized in that: Also includes: Determine whether the oscillation amplitude is greater than or equal to a first threshold.

4. The power oscillation suppression method according to claim 1 or 3, characterized in that: After adjusting the phase correction angle and gain, also include: Determining whether the oscillation amplitude is less than or equal to a second threshold; If the oscillation amplitude is less than or equal to the second threshold, the loop gain of the additional signal is gradually reduced, and the additional dq-axis current instructions are gradually removed to restore the normal working state of the power converter.

5. The power oscillation suppression method according to claim 1 or 4, characterized in that: The obtaining of the oscillation frequency and oscillation amplitude of the power system comprises: Obtain the oscillation frequency and the oscillation amplitude that needs to be suppressed provided by the power grid company.

6. The power oscillation suppression method according to claim 5, characterized in that: The first condition also includes that the power grid company needs to provide a power oscillation suppression function; the method also includes: If the power grid company needs to provide a power oscillation suppression function, it is determined that the first condition is met.

7. The power oscillation suppression method according to claim 6, characterized in that: After adjusting the phase correction angle and gain, also include: Determine whether the grid company needs to provide power oscillation suppression function; If the power grid company does not need to provide a power oscillation suppression function, the dq-axis current command is removed to restore the normal working state of the power converter.

8. A controller connected to a power converter for controlling a switch state in the power converter, characterized in that: The controller comprises: Memory for storing computer programs; A processor is used to execute the computer program stored in the memory. When the computer program is executed, the processor is used to execute the power oscillation suppression method according to any one of claims 1 to 7.

9. A storage medium, characterized in that: The storage medium comprises computer instructions, and when the computer instructions are executed on the controller, the controller is caused to execute the power oscillation suppression method according to any one of claims 1 to 7.

10. A power oscillation suppression system, characterized in that: The power oscillation suppression system comprises a power converter and a controller as claimed in claim 8, wherein the controller is electrically connected to the power converter and is used to control a switch state in the power converter.

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