A power distribution network customer side loop resonance active suppression method and system

Abstract

The present application relates to a kind of distribution network user side loop resonance active suppression method and system, by real-time monitoring and calculating harmonic distortion rate and key frequency point amplitude, whether the system is in resonance state is intelligently judged.When potential resonance risk is detected, actively start resonance suppression device work, actively destroy resonance occurrence condition, the resonance suppression device has two control modes: damping enhancement mode is by input resistor to improve system damping, effectively suppress resonance energy accumulation;Damping enhancement and frequency offset collaborative mode, in combination with damping enhancement mode, then by adjusting capacitor switching capacity, change system inherent resonance frequency, make it deviate from current harmonic frequency, to avoid resonance, the control algorithm of resonance active suppression device is realized by PID algorithm.The present application is suitable for the low-frequency harmonic resonance problem caused by nonlinear load in user side low-voltage distribution network, and is suitable for the comprehensive treatment of resonance problem in industrial, commercial and civil power system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power quality of power supply and distribution of power systems, and in particular to a power distribution network user side loop resonance active suppression method and system. BACKGROUND

[0002] In the user side low-voltage power distribution network, the widespread application of nonlinear loads (such as frequency converters, LED lighting, charging piles, etc.) leads to increasingly serious harmonic pollution problems. When the harmonic frequency is close to the inherent resonance frequency of the power distribution system, series resonance or parallel resonance may be triggered, which may cause bus voltage distortion, equipment overheating, relay protection misoperation and other safety hazards. Traditional resonance suppression techniques absorb specific harmonics through LC tuning circuits, but are only suitable for fixed frequency scenarios and may introduce new resonance points. Dynamic compensation of harmonics based on power electronic devices (such as insulated gate bipolar transistors) is costly and highly dependent on control algorithms. Artificial adjustment of system capacitance or reactance parameters to avoid resonance points is slow in response and cannot adapt to dynamic load changes.

[0003] Chinese patent application No. CN202310297157.4 provides a device and method for realizing resonance suppression and impedance measurement of a power distribution network. The device injects current into the power grid to achieve harmonic suppression of the power distribution network, i.e., active suppression of resonance. Current resonance suppression schemes mainly target the power grid side or transmission lines. The impedance characteristics on the power grid side or transmission lines are mainly reactance, with a small resistance component, making it prone to high-frequency resonance. This is different from the user side loop in the present application, which has a larger resistance component, resulting in resonance peak attenuation and generally low-frequency resonance. Therefore, the harmonic source of the user side loop is mainly low-order harmonics, and the power grid side or transmission line scheme has limited effect on low-order harmonic suppression.

[0004] In summary, there is currently a lack of a resonance active suppression method for the user side loop. SUMMARY

[0005] The purpose of the present application is to overcome the shortcomings of the prior art and provide a power distribution network user side loop resonance active suppression method and system to solve or partially solve the harmonic resonance problem caused by nonlinear loads in the user side power distribution system.

[0006] The purpose of the present application can be achieved by the following technical solutions:

[0007] In one aspect of the present application, a power distribution network user side loop resonance active suppression method is provided, comprising the following steps:

[0008] Obtain user side loop resistance range mapping information and available capacitor bank switching combinations;

[0009] Obtaining user side loop voltage and / or current signal, extracting harmonic spectrum through Hanning Window, obtaining dominant harmonic frequency and amplitude, calculating harmonic energy;

[0010] Based on the dominant harmonic frequency and amplitude, determining whether resonance occurs, and in response to the occurrence of resonance, entering a damping priority control mode or a cooperative control mode based on the resonance duration;

[0011] In the damping priority control mode, based on the resistance gear mapping information, the resistance switching value corresponding to the harmonic energy is obtained, the pulse width modulation is performed on the Insulate-Gate Bipolar Transistor (IGBT) device to realize resistance switching, and in response to the fact that the harmonic is not eliminated after the preset time threshold, the cooperative control mode is entered.

[0012] In the cooperative control mode, the capacitor group switching value is calculated based on the dominant harmonic frequency and the available capacitor groups are switched, the resistance switching value is calculated and switched, and the frequency offset and resistance input are closed-loop optimized based on the harmonic amplitude decay rate.

[0013] As a preferred technical solution, the resistance gear mapping information is used to obtain the resistance switching value corresponding to the harmonic energy, which is realized by the following formula:

[0014]

[0015]

[0016] wherein, is the harmonic energy, is the harmonic amplitude, is the harmonic occurrence time, is the current time, is the resistance switching value.

[0017] As a preferred technical solution, the damping priority control mode or the cooperative control mode is entered based on the resonance duration, which includes the following steps:

[0018] If the resonance duration is less than 50ms or the harmonic energy is less than , the damping priority control mode is entered, otherwise the cooperative control mode is entered.

[0019] As a preferred technical solution, the determination of whether resonance occurs based on the dominant harmonic frequency and amplitude includes the following steps:

[0020] If the dominant harmonic frequency is within the range of resonance frequency ±5Hz, and the dominant harmonic amplitude is greater than the preset value.

[0021] As a preferred technical scheme, the capacitor bank switching value based on the dominant harmonic frequency is calculated by using the following formula:

[0022]

[0023]

[0024] wherein, is a frequency offset, and the capacitor bank switching is triggered only when the frequency offset is greater than or equal to 10 Hz, is a current detected dominant harmonic frequency, is a resonant frequency, is a normal working frequency of the power distribution network, is an equivalent inductance of the power distribution network, is an existing capacitance of the power distribution network, is a capacitor bank switching value.

[0025] As a preferred technical scheme, the frequency offset and resistance input are closed-loop optimized based on the harmonic amplitude decay rate by using the following formula:

[0026]

[0027]

[0028] wherein, is a frequency offset and resistance input adjustment amount, , , is a coefficient, is a target harmonic amplitude, is a target harmonic, is a target harmonic.

[0029] As a preferred technical scheme, in the process of judging whether resonance occurs based on the dominant harmonic frequency and amplitude, the following steps are further included:

[0030] It is judged whether the phase angle change degree of the harmonic phase in a preset time is greater than a preset value, and if yes, it is determined that the transient interference is temporary, and the suppression action is blocked.

[0031] In another aspect of the present application, a power distribution network user side loop resonance active suppression system is provided, comprising:

[0032] A resonance detection module is used to collect user side loop bus voltage and / or current signals in real time, analyze the harmonic frequency spectrum through Fourier transform, extract the dominant harmonic frequency and amplitude, and calculate the harmonic energy.

[0033] A capacitor reactive power compensation module includes a plurality of groups of parallel capacitors arranged for grouping switching, and the grouping switching is realized through thyristor switches.

[0034] An electronic dynamic adjustment module, including a multi-stage segmented series resistor, is controlled to be connected by an IGBT driving circuit;

[0035] A coordination controller is used to implement the power distribution network user side loop resonance active suppression method, and resonance suppression is achieved by dynamically adjusting the capacitor reactive power compensation module and the electronic dynamic adjustment module.

[0036] In another aspect of the present application, an electronic device is provided, comprising one or more processors and a memory, the memory having stored therein one or more programs, the one or more programs including instructions for implementing the foregoing power distribution network user side loop resonance active suppression method.

[0037] In another aspect of the present application, a computer-readable storage medium is provided, comprising one or more programs for execution by one or more processors of an electronic device, the one or more programs including instructions for implementing the foregoing power distribution network user side loop resonance active suppression method.

[0038] Compared with the prior art, the present application has at least one of the following beneficial effects:

[0039] Improve the real-time and adaptability of resonance suppression: The present application provides a dual-mode cooperative control mechanism of damping priority control mode and cooperative control mode to solve the problem that the existing resonance suppression method has insufficient dynamic response capability and cannot quickly and adaptively process different degrees of harmonic resonance caused by nonlinear load on the user side. The harmonic frequency and amplitude are collected in real time by a resonance detection module, and the coordination controller automatically switches modes according to the resonance duration and harmonic energy, quickly puts in the segmented resistance or cooperatively adjusts the resistance and capacitor, realizes targeted suppression of different types of resonance, and the response time is much faster than traditional passive filtering. It can dynamically adapt to load changes, avoid the limitations of a single mode, and significantly improve the real-time and adaptability of resonance suppression.

[0040] Avoid introducing new resonance risks: The present application solves the problem that traditional passive devices are only suitable for fixed frequency scenarios and are prone to introducing new resonance points, and active devices have high cost and rely on complex control algorithms, making it difficult to balance suppression effect and energy consumption. The capacitor reactive power compensation module is designed to dynamically adjust the capacitor capacity to change the system's inherent resonance frequency, and the resistance dynamic adjustment module is designed to adaptively select resistance values according to harmonic energy. The resistance is completely removed when there is no resonance. Without complex power electronic devices, the resonance point is actively avoided in a passive manner, avoiding the risk of introducing new resonances. In the non-resonance state, the system loss is close to zero, and the operating loss is lower than that of traditional passive filtering, balancing the suppression effect and economy.

[0041] Stable suppression of resonance in complex scenarios such as load mutation: The present application aims at the problem that the traditional impedance parameter adjustment method relies on manual operation and cannot be optimized in real time, the existing control algorithm lacks closed-loop feedback and has poor dynamic adaptability, and it is difficult to guarantee the continuous and stable suppression effect. The voltage amplitude and frequency double variable proportional-integral-derivative (PID) control is introduced, the resonance amplitude and frequency after suppression are fed back in real time through the resonance detection module, and the resistance value and capacitance switching amount are dynamically adjusted by the coordination controller according to the deviation, forming a closed-loop optimization. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 Flowchart of the power distribution network user side loop resonance active suppression method in the embodiment;

[0043] Figure 2 Voltage amplitude and frequency double variable PID control schematic diagram in the embodiment;

[0044] Figure 3 Schematic diagram of the power distribution network user side loop resonance active suppression system in the embodiment;

[0045] Figure 4 Schematic diagram of the electronic device in the embodiment. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor should be within the scope of protection of the present application.

[0047] Embodiment 1

[0048] In view of the problem that the existing resonance suppression scheme for the power grid side or transmission line cannot perceive whether the user side loop resonates, and in view of the problem that the low-order harmonic suppression effect is limited, the present embodiment provides a power distribution network user side loop resonance active suppression method to dynamically suppress resonance. The power capacitor and resistor are designed by an intelligent control algorithm, that is, the impedance characteristics of the system are actively adjusted by the cooperative control of the capacitor and the resistor, so as to actively destroy the resonance condition and suppress the occurrence of resonance, which is suitable for solving the problem of power distribution network low-frequency harmonic resonance caused by user side electric vehicle charging, variable frequency equipment and other nonlinear loads, especially photovoltaic and other new energy access.

[0049] Referring to Figure 1 , the method comprises the following steps:

[0050] Step S1, initialization.

[0051] The total harmonic distortion (THD) threshold is set to 5%, the resonance frequency detection range is 150Hz-1.25kHz, the pre-defined capacitor group switching combination is 4 groups of 50kvar, and the resistance level mapping table (i.e. harmonic energy E h corresponding to the resistor switching value R add ).

[0052] Step S2, power quality harmonic analysis.

[0053] A high-precision sensor is used to collect voltage / current signals at a period of 10ms, and a sliding window Fast Fourier Transform (FFT) with a Hanning window is used to extract harmonic frequency spectrum within 25 times, to calculate the dominant harmonic frequency f h and amplitude V h , and to integrate and calculate the harmonic energy .

[0054] Step S3, resonance judgment and mode switching. If resonance does not occur, step S2 is executed

[0055] First, it is detected whether resonance occurs. The resonance condition is f h ∈( f res ±5Hz) and V h >5% V rated , where f res is the resonance frequency, V rated and is the preset threshold.

[0056] Then, when it is judged that resonance occurs, the control mode (mode one or mode two) is selected according to the resonance duration.

[0057] It is judged whether the triggering condition of mode one damping mode (i.e. damping priority control mode) is met. If yes, resistor switching value R add resistance value dynamic control is performed. If not, mode two cooperative control mode is entered. Specifically, the triggering condition is that if the resonance duration t res is less than 50ms or the energy harmonic is less than If yes, enter mode one, only input series resistor, quickly suppress the resonance amplitude. Otherwise enter mode two, adjust capacitor group with resistor R add , achieve resonance frequency shift and damping enhancement synergy.

[0058] Preferred, also includes harmonic detection anti-interference step, using harmonic phase mutation detection, if the harmonic phase changes more than 30 ° in 1 ms, determine the load switching transient disturbance, lockout suppression action.

[0059] (1) damping mode.

[0060] After 50 ms of damping mode adjustment, determine whether the resonance phenomenon is eliminated, if yes, end the resonance suppression, if not, enter mode two synergy control mode.

[0061] Damping enhancement model is constructed as, system damping ratio Zeta determined by series resistance R add and system parameters:

[0062]

[0063] When the resistance value is dynamically selected, according to the harmonic energy Segmented adjustment of series resistance R add value:

[0064]

[0065] Damping mode according to resistance gear mapping table selection resistor switch value R add , specifically, when the harmonic energy Less than 10 3 V 2 s, then R add 0.5 Ω, if the harmonic energy is greater than or equal to And less than , R add 1 Ω, if the harmonic energy is greater than , R add 2 Ω. Through the pulse width modulation (PWM) control of IGBT drive circuit, avoid current impact, response time less than or equal to 1 ms. Series resistor adopts multi-stage segmented structure, such as 0.1 Ω, 0.5 Ω, 1 Ω, 1.5 Ω, 2 Ω.

[0066] (2) synergy control mode.

[0067] In the cooperative control mode, frequency offset control and damping enhancement control are carried out through the capacitor controller and the resistor controller respectively, the control process is closed-loop adjusted based on the PID control algorithm, real-time feedback optimization is carried out, and the resonance reset and end are eliminated.

[0068] A resonance frequency offset model is constructed for the power distribution system resonance equivalent inductance and equivalent capacitor LC circuit to be generated, and the power distribution system resonance frequency is determined by the equivalent inductance L sys and the equivalent capacitance C eq of the power distribution network.

[0069] The dynamic adjustment of the equivalent capacitance is that the shunt capacitor bank adopts a grouping switching strategy, and the total capacity is changed by switching the switch:

[0070]

[0071]

[0072] wherein, C is the existing capacitance capacity of the power distribution system itself, N N is the number of switched capacitor banks, and C is the single group capacity.

[0073] The frequency offset target is that when the current harmonic frequency f h is close to the resonance frequency , by adjusting to make deviate from , the resonance point is avoided.

[0074] The cooperative mode also performs frequency offset control on the basis of resistor switching value control, when the frequency offset Δ f satisfies f h - f res |≥10Hz, calculate the capacitor bank switching value Δ C = 1 / [(2π f target ) 2 L sys ] - C base , and the grouping switching is realized by a thyristor (SCR) switch.

[0075] Step S4, PID control algorithm.

[0076] The PID control equation is as follows:

[0077]

[0078] wherein , is the frequency offset, the resistance input adjustment amount, , , is the coefficient, is the target harmonic amplitude, is the first actual target harmonic.

[0079] Referring to Figure 2 , the target dominant harmonic amplitude V h and the target dominant harmonic frequency f h are preset, and the difference between the actual dominant harmonic amplitude V h and the actual dominant harmonic frequency f h obtained by the resonance detection module is taken as the input of the PID control algorithm in the resistance dynamic controller and the capacitance dynamic controller, to obtain the capacitor bank switching value and the resistance switching value, which are used to adjust the capacitor bank and the resistor bank, respectively.

[0080] Preferably, when the capacitor bank is switched, if the triggering of a certain group of thyristors fails, the system automatically switches to a standby group, records the fault code, and forces the switching interval to be ≥100 ms to avoid overheating of the devices caused by frequent operation. When the resistance module is switched, the resistance temperature T is monitored in real time T , and if R add >80℃, the resistance value is gradually reduced by 10% steps, and when the temperature exceeds the limit, the resistance is forcibly removed and an emergency alarm is triggered.

[0081] To verify the effectiveness of the method, a user-side power distribution system model is built in MATLAB / Simulink, with parameters of system voltage 400V / 50Hz, short-circuit capacity S sc = 10MVA, and load being a frequency converter (which has 5th and 7th harmonics) and LED lighting (which has 3rd harmonics). The controller parameters are =0.8, =0.2, =0.1.

[0082] The method is compared with the passive filtering method under the following two scenarios:

[0083] (1) 5th harmonic resonance (250Hz)

[0084] Before suppression: = 8.5%, resonance lasts 120 ms.

[0085] After inhibition: put in 2Ω resistance and cut off 1 group of capacitor, Down to 2.1%, time-consuming 18 ms.

[0086] (2) Dynamic load switching

[0087] When simulating load mutation, the controller detects the misoperation of phase mutation lockout, and the system has no disturbance.

[0088] The performance comparison of this method and passive filtering is shown in Table 1.

[0089] Table 1 Performance comparison of this method and passive filtering

[0090]

[0091] Example 2

[0092] Based on Example 1, see Figure 3 , the power distribution network user side loop resonance active suppression system mainly includes the following modules:

[0093] (1) Resonance detection module.

[0094] Real-time acquisition of bus voltage / current signals, harmonic spectrum analysis by FFT;

[0095] Based on fast Fourier transform analysis of harmonic spectrum, extraction of dominant harmonic frequency f h and amplitude V h .

[0096] Capacitor reactive power compensation module.

[0097] Parallel capacitor bank adopts grouping switching design, 4 groups x 50kvar, realizes grouping switching through thyristor switch, supports dynamic capacity adjustment , used to change the system resonance frequency f res . The capacitor bank is installed with heat dissipation fins, which triggers the capacity reduction operation when the environmental temperature exceeds 40℃.

[0098] (3) Resistance dynamic adjustment module.

[0099] Series resistor adopts multi-stage segmented structure, such as 0.1Ω, 0.5Ω, 1Ω, 1.5Ω, 2Ω, the resistance value is controlled by IGBT driving circuit, combined with PWM modulation, to realize the fast input and cut-off of resistance, the response time is less than or equal to 1 ms. The resistance is configured with axial flow fan, and the temperature control switch sets the protection threshold.

[0100] (4) intelligent coordination controller.

[0101] The integrated resonance judgment algorithm and the collaborative control model are used to make decisions on capacitor switching and resistance value adjustment, the core is an embedded processor, the power distribution network user side loop resonance active suppression method in embodiment 1 is run, and a communication interface supports a Modbus / TCP protocol, and data is interacted with an upper computer in real time.

[0102] The intelligent coordination controller core model can dynamically adjust and control the impedance characteristics of the power supply and distribution loop, so that the resonance phenomenon at different resonance points can be suppressed, and the present application provides a simple, reliable and passive resonance active suppression method for resonance treatment.

[0103] The present application judges whether the system is in a resonance state by real-time monitoring and calculating the harmonic distortion rate and the amplitude of the key frequency point. When potential resonance risk is detected, the resonance suppression device is actively started to work and actively destroy the resonance occurrence condition. The resonance suppression device has two control modes: a damping enhancement mode that improves system damping by adding resistors to effectively suppress resonance energy accumulation; and a damping enhancement and frequency offset collaborative mode that combines the damping enhancement mode and further adjusts the capacitor switching capacity to change the system's inherent resonance frequency, so that it deviates from the current harmonic frequency, thereby avoiding resonance. The control algorithm of the resonance active suppression device is realized by a PID algorithm. The present application is suitable for low-frequency harmonic resonance problems caused by nonlinear loads such as electric vehicle charging, frequency converters, LED lighting equipment, and especially new energy such as photovoltaic in the user side low-voltage power distribution network, can significantly improve the power quality of the user side power grid, and ensure the safe operation of the equipment, and is suitable for comprehensive treatment of resonance problems in industrial, commercial and civil power systems.

[0104] Embodiment 3

[0105] On the basis of the foregoing embodiments, the present embodiment provides an electronic device, comprising: one or more processors and a memory, the memory has one or more programs stored therein, and the one or more programs include instructions for executing the power distribution network user side loop resonance active suppression method as described in embodiment 1.

[0106] As Figure 4 described, at the hardware level, the electronic device includes a processor, an internal bus, a network interface, a memory, and a non-volatile memory, and of course can also include other hardware required by the business. The processor reads the corresponding computer program from the non-volatile memory into the memory and then runs to implement the above Figure 1 described method. Of course, in addition to the software implementation, the present application does not exclude other implementation manners, such as logic devices or a combination of software and hardware, etc., that is, the execution subject of the following processing flow is not limited to each logic unit, but can also be hardware or a logic device.

[0107] Memory can include non-persistent memory in computer-readable media, random access memory (RAM), and / or non-volatile memory such as read-only memory (ROM) or flash memory (flash RAM). Memory is an example of computer-readable media.

[0108] Computer-readable media includes permanent and non-permanent, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD), or other optical storage, magnetic cassette, disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information accessible to a computing device. According to the definition herein, computer-readable media does not include transitory media such as modulated data signals and carriers.

[0109] The above description is merely a specific implementation of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present application, and these modifications or replacements should be covered within the scope of protection of the present application. Therefore, the scope of protection of the present application should be subject to the scope of protection of the claims.

Claims

1. A method for actively suppressing resonance in the user-side circuit of a distribution network, characterized in that, Includes the following steps: Obtain user-side circuit resistance level mapping information and available capacitor bank switching combinations; Acquire user-side loop voltage and / or current signals, extract harmonic spectrum through Hanning window sliding to obtain dominant harmonic frequency and amplitude, and calculate harmonic energy; Based on the dominant harmonic frequency and amplitude, it is determined whether resonance occurs. In response to resonance, based on the duration of resonance, it enters the damping priority control mode or the cooperative control mode. In the damping priority control mode, the resistor switching value corresponding to the harmonic energy is obtained based on the resistor level mapping information. The resistor switching is achieved by pulse width modulation of the IGBT device. If the harmonic is not eliminated after a preset time threshold, the system enters the cooperative control mode. In the cooperative control mode, the capacitor bank switching value is calculated based on the dominant harmonic frequency and the available capacitor banks are switched. The resistor switching value is calculated and switched. The frequency offset and resistor input are optimized in a closed loop based on the harmonic amplitude attenuation rate.

2. The active suppression method for user-side circuit resonance in a distribution network according to claim 1, characterized in that, The resistor switching value corresponding to the harmonic energy, based on the resistor range mapping information, is obtained using the following formula: in, Harmonic energy For harmonic amplitude, The time when harmonics occur, For the current moment, This represents the resistor switching value.

3. The active suppression method for user-side circuit resonance in a distribution network according to claim 1, characterized in that, The process of entering the damping priority control mode or cooperative control mode based on the resonance duration includes the following steps: If the resonance duration is less than 50ms or the harmonic energy is less than If the damping priority control mode is entered, the coordinated control mode will be entered otherwise.

4. The active suppression method for user-side circuit resonance in a distribution network according to claim 1, characterized in that, The method for determining whether resonance has occurred based on the dominant harmonic frequency and amplitude includes the following steps: If the dominant harmonic frequency is within ±5Hz of the resonant frequency, and the dominant harmonic amplitude is greater than the preset value.

5. The active suppression method for user-side circuit resonance in a distribution network according to claim 1, characterized in that, The calculation of capacitor bank switching values ​​based on the dominant harmonic frequency is achieved using the following formula: in, This is the frequency offset, and capacitor bank switching is triggered only when the frequency offset is greater than or equal to 10Hz. The dominant harmonic frequency currently being detected. The resonant frequency, This is the normal operating frequency of the distribution network. For the equivalent inductance of the distribution network, For the existing capacitor capacity of the distribution network, This is the switching value for the capacitor bank.

6. The active suppression method for user-side circuit resonance in a distribution network according to claim 1, characterized in that, The closed-loop optimization of frequency offset and resistor input based on harmonic amplitude attenuation rate is achieved using the following formula: in, For frequency offset and resistance adjustment, , , For coefficients, For the target harmonic amplitude, For the first A real target harmonic.

7. The active suppression method for user-side circuit resonance in a distribution network according to claim 1, characterized in that, The process of determining whether resonance has occurred based on the dominant harmonic frequency and amplitude also includes the following steps: Determine whether the phase angle change of the harmonic phase within a preset time is greater than a preset value. If so, it is determined to be a transient interference, and a blocking suppression action is initiated.

8. An active suppression system for user-side circuit resonance in a distribution network, characterized in that, include: The resonance detection module is used to acquire the voltage and / or current signals of the user-side circuit bus in real time, analyze the harmonic spectrum through Fourier transform, extract the dominant harmonic frequency and amplitude, and calculate the harmonic energy. The capacitor reactive power compensation module includes multiple groups of parallel capacitors that are switched in groups, and the switching in groups is achieved through thyristor switches; The electronic dynamic adjustment module includes a multi-stage segmented series resistor, the resistance value of which is controlled by the IGBT drive circuit; A coordination controller is used to implement the active suppression method for user-side circuit resonance in the distribution network as described in any one of claims 1-7, and to achieve resonance suppression by dynamically adjusting the capacitor reactive power compensation module and the electronic dynamic adjustment module.

9. An electronic device, characterized in that, include: One or more processors and a memory, wherein the memory stores one or more programs, the one or more programs including instructions for executing the active suppression method for user-side circuit resonance in a distribution network as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, It includes one or more programs executed by one or more processors of an electronic device, the one or more programs including instructions for performing the active suppression method for user-side loop resonance in a distribution network as described in any one of claims 1-7.

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