Power system frequency adjusting method based on 5G transmission

Abstract

The invention discloses a power system frequency adjustment method based on 5G transmission. The method comprises the following steps: acquiring electrical characteristic data of each node in a power grid; the electrical characteristic data comprises current, voltage and frequency; analyzing and processing the collected electrical characteristic data, positioning an area where a fault or frequency mutation occurs in the power grid, and identifying a fault occurrence point; and frequency fluctuation is adjusted through power angle compensation control of the inverter, so that the frequency of the power grid is gradually recovered to a normal value. According to the invention, efficient and accurate frequency monitoring and adjustment can be realized, and the stability and reliability of the system are improved.

Description

Technical Field

[0001] The present invention relates to the field of power systems, and in particular to a method for regulating the frequency of a power system based on 5G transmission. Background Art

[0002] The frequency regulation of the power system is related to the stable operation of the power grid and the maintenance of the balance between power supply and demand. Therefore, the frequency regulation of the power system is crucial. Traditional power system frequency regulation usually relies on the regulation of generator sets or large energy storage devices to maintain the stability of the system frequency. However, with the large-scale access of renewable energy such as wind power and solar energy, the frequency stability of the power system faces new challenges.

[0003] Due to the volatility and intermittency of these renewable energy sources, frequency fluctuations are more frequent, and traditional regulation methods are difficult to cope with real-time changes. In addition, existing frequency monitoring and regulation systems mostly rely on lower bandwidth and slower communication technologies (such as traditional power line carrier communication), resulting in large data transmission delays and inability to accurately respond to frequency mutations in real time, which in turn affects the stability of the system.

[0004] Therefore, a power system frequency regulation method based on 5G transmission is needed to achieve efficient and accurate frequency monitoring and regulation, and improve system stability and reliability. Summary of the invention

[0005] In view of this, the purpose of the present invention is to overcome the defects in the prior art and provide a power system frequency regulation method based on 5G transmission, which can realize efficient and accurate frequency monitoring and regulation and improve system stability and reliability.

[0006] The power system frequency regulation method based on 5G transmission of the present invention includes:

[0007] Collecting electrical characteristic data of each node in the power grid; the electrical characteristic data includes current, voltage and frequency;

[0008] Analyze and process the collected electrical characteristic data, locate the area where the fault or frequency mutation occurs in the power grid, and identify the fault point;

[0009] The frequency fluctuation is adjusted through the power angle compensation control of the inverter, so that the frequency of the power grid gradually returns to normal.

[0010] Furthermore, the electrical characteristic data of each node in the power grid is collected, including:

[0011] A distributed measurement method is adopted, and sensors are installed at each node to collect and monitor current, voltage and frequency in the power system in real time; the sensors include current transformers, voltage transformers and power probes.

[0012] Further, the collected electrical characteristic data is analyzed and processed, specifically including:

[0013] Filter and denoise the collected signals to remove high-frequency noise and interference;

[0014] The collected data is transmitted to the dispatch center through 5G communication technology to remove duplicate values ​​and abnormal values;

[0015] Construct a power load distribution prediction model to predict future power load distribution.

[0016] Furthermore, the collected signal is filtered and denoised, specifically including:

[0017] Decompose the original signal by wavelet to obtain wavelet coefficients of multiple scales;

[0018] Threshold processing is performed on the wavelet coefficients of each scale, the coefficients less than a certain threshold are set to 0, and the coefficients greater than or equal to the threshold are retained;

[0019] Perform wavelet reconstruction on the processed wavelet coefficients to obtain the denoised signal;

[0020] Repeat the above steps until the stopping criterion is met.

[0021] Furthermore, a power load distribution prediction model is constructed to predict future power load distribution, including:

[0022] Based on long short-term memory network, a power load distribution prediction model is constructed;

[0023] Training the power load distribution prediction model to obtain a trained prediction model;

[0024] The trained prediction model is deployed to the edge server and cloud server to predict the input load data, transmission power and number of service users to obtain the future power load distribution.

[0025] Furthermore, the frequency fluctuation is adjusted by the power angle compensation control of the inverter, which specifically includes:

[0026] The power angle compensation control of the inverter includes:

[0027] The power angle compensation control transforms the three-phase voltage V abc , three-phase voltage U on the grid side abc Three-phase current I abc Converted to V in dq0 coordinate system d ,V q and I d ,I q ; The phase-locked loop controls Vd ,V q and U d ,U q Perform phase adjustment and obtain the phase angle through the integrator 1 / s; adjust the power angle through the PID controller and output the phase compensation angle δ1; the final phase angle δ is obtained by taking the remainder of δ1 and limiting the compensation phase angle to between positive and negative pi; the phase angle δ is used as the input of the power loop to adjust the phase of the inverter output voltage;

[0028] The voltage loop controls the following: the voltage loop receives the voltage command output by the power loop and the actual voltage v od ,v oq ; By calculating the error and Get the error signal; proportional controller K pv Perform preliminary adjustment on the error signal; the integrator integrates the error signal at 1 / s to generate an integral control signal Voltage feedback control K iv The signal output by the integrator is compared with the actual current i od ,i oq Compare and get the current reference value Generated current reference value As the input of the current loop;

[0029] The current loop control includes: the current loop receives the current reference value directly and the actual current i ld ,i lq ; By calculating the error and The error signal is obtained; the proportional controller Kpc performs preliminary adjustment on the error signal; the integrator 1 / s integrates the error signal to generate an integral control signal γ d ,γ q The current feedback control Kic compares the signal output by the integrator with the output of the voltage loop to obtain the final control voltage The final control voltage As the input of PWM modulation;

[0030] PWM modulation includes: output voltage instruction of current loop Expressed in the dq0 coordinate system; through coordinate transformation, Converted into a three-phase voltage signal in the abc coordinate system; the PWM gain module adjusts the amplitude of the three-phase voltage signal to meet the requirements of the PWM modulation module; the PWM module receives the adjusted three-phase voltage signal and converts it into a PWM signal for controlling power switching devices such as IGBT.

[0031] Furthermore, the voltage loop is composed of output voltage current feedback and two PI controllers; where F is the current feedback coefficient, Kpv is the proportional gain of the voltage loop PI controller, and Kiv is the integral gain; the integral link output of the two PI controllers They can be expressed by the following differential equations:

[0032]

[0033] Among them, v od * is the power loop d-axis output voltage reference, v od is the power loop d-axis output voltage, v oq * is the power loop q-axis output voltage reference, v oq is the q-axis output voltage of the power loop;

[0034] The voltage loop outputs ild and ilq can be expressed by the following equations:

[0035]

[0036] Among them, i od is the inverter d-axis output current, ω n is the system rated angular frequency, C f is the filter capacitor, i oq is the inverter q-axis output current.

[0037] Furthermore, the current loop is composed of the filter front-stage inductor current feedback and two PI controllers; Kpc is the proportional gain of the current loop PI controller, and Kic is the integral gain; the integral link outputs γd and γq of the two PI controllers can be expressed by the following differential equations:

[0038]

[0039] Among them, i ld * is the reference current of the d-axis of the current loop, i ld is the d-axis current of the current loop, i lq * is the reference current of the current loop q axis, i lq is the q-axis current of the current loop;

[0040] The current loop outputs vid and viq can be expressed by the following equations:

[0041] v id * =-ω n L f i lq +K pc (i ld* -i ld )+K ic γ d

[0042] v iq * =ω n L f i ld +K pc (i lq * -i lq )+K ic γ q

[0043] Among them, K pc is the proportional gain of the current loop PI controller, K ic is the integral gain.

[0044] Furthermore, the specific process of the power ring processing data includes:

[0045] The data input to the power loop includes: the dq component of the voltage v od ,v oq and the dq components of the current i od ,i oq ;

[0046] The power loop is first calculated by the formula p = v od i od +v oq i oq Get the active power P; by calculating the formula q = v oq i od -v od i oq The reactive power Q is obtained; the active power P and the reactive power Q are filtered in the first order to obtain a smooth power signal;

[0047] Active power control is achieved through the equation ω n -m(PP set ) to obtain the phase angle θ, and integrate it through the integrator 1 / s.

[0048] Furthermore, the input v of the power loop od 、v oq 、i od 、i oq is the inverter output voltage v o With the output current i o The d and q axis components of the inverter are shown in Figure 2, where δ is the inverter power angle compensation angle. The equation of the first-order filter link is:

[0049]

[0050] Where P is the active power after filtering, ω c is the filter corner frequency, s is the Laplace variable, p is the active power before filtering, Q is the reactive power after filtering, and q is the reactive power before filtering;

[0051] By controlling the power angle and output voltage of the inverter, the active and reactive power can be controlled. The angular frequency is used instead of the power angle to obtain the active-frequency droop equation:

[0052] ω=ω n -m(PP set )

[0053] θ=ω n t-∫m(PP set )dt

[0054] Among them, P is the inverter output active power, P set is the active power given, ω n is the system rated angular frequency, ω is the inverter angular frequency, θ is the inverter phase angle, and m is the droop coefficient.

[0055] The beneficial effects of the present invention are as follows: the power system frequency regulation method based on 5G transmission disclosed by the present invention can more accurately monitor the power grid frequency in real time, quickly locate the source of frequency anomalies, and stabilize the system frequency through efficient control means by combining the distributed measurement system and the inverter power angle compensation control, thereby solving the frequency regulation problem faced by the current power system, improving the system stability and reliability, and reducing the impact of frequency fluctuations on system operation. The present invention can not only monitor the power grid status in real time and quickly locate the cause of frequency mutations, but also restore frequency fluctuations through precise control, and is suitable for intelligent regulation and stability assurance in modern power systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0057] Figure 1 It is a schematic flow chart of the method for regulating the frequency of a power system according to the present invention. DETAILED DESCRIPTION

[0058] The present invention is further described below in conjunction with the accompanying drawings, as shown in the drawings:

[0059] This embodiment discloses a method for adjusting the frequency of a power system based on 5G transmission, comprising the following steps:

[0060] Collecting electrical characteristic data of each node in the power grid; the electrical characteristic data includes current, voltage and frequency;

[0061] Analyze and process the collected electrical characteristic data, locate the area where the fault or frequency mutation occurs in the power grid, and identify the fault point;

[0062] The frequency fluctuation is adjusted through the power angle compensation control of the inverter, so that the frequency of the power grid gradually returns to normal.

[0063] The present invention aims to improve the stability of the power system and reduce the impact of frequency fluctuations on system operation by monitoring the frequency of power equipment in real time and adjusting the recovery frequency through the power angle compensation control of the inverter when the frequency changes suddenly.

[0064] In this embodiment, the electrical characteristic data of each node in the power grid is collected, specifically including:

[0065] A distributed measurement method is adopted, and sensors are installed at each node to collect and monitor current, voltage and frequency in the power system in real time; the sensors include current transformers, voltage transformers and power probes.

[0066] Specifically, data is collected through a distributed measurement system (DAS) to monitor the operating status of each device in the power grid in real time. The collected data includes important parameters such as voltage, current, and frequency. In order to achieve global monitoring, the system deploys multiple sensors in the distribution network to measure the electrical characteristics of each node in the power grid in a distributed manner. Especially in terms of frequency monitoring, the orthogonal average CZT algorithm is used to accurately calculate the AC frequency of each node in the power system. This algorithm can effectively filter noise and efficiently calculate frequency deviation with high accuracy and real-time performance. Through the above measures, the system can obtain real-time voltage, current, and frequency data of each node, and summarize the global status of the power grid in real time through a distributed sensor network, providing the necessary basic data for subsequent frequency regulation.

[0067] Current transformer (CT): used to measure large current and convert it into a smaller proportional current signal. LZZBJ9-35 is suitable for power systems with a rated frequency of 50Hz or 60Hz and a rated voltage of 35kV and below. LMK-0.66 is suitable for power systems with a rated frequency of 50Hz and a rated voltage of 0.66kV and below.

[0068] Voltage transformer (VT): used to measure voltage and convert high voltage into measurable low voltage signal. For 220kV main grid, you can choose cascade electromagnetic voltage transformer; for 110kV main grid, you can choose JDCF-110WB; for 10kV main grid, you can choose JDCF-220WB.

[0069] Use power probe: Power probe can directly measure and obtain the active power and reactive power of the circuit. Active power is the power actually consumed in the circuit, while reactive power is the power stored or transmitted in the circuit. Power probe can also measure and obtain the power factor in the circuit. Power factor refers to the ratio of useful power to apparent power in the circuit, which directly reflects the efficiency of energy consumption in the circuit. DTSU71C intelligent power sensor can be used.

[0070] In this embodiment, the collected electrical characteristic data is analyzed and processed, specifically including:

[0071] Filter and denoise the collected signals to remove high-frequency noise and interference, including:

[0072] Decompose the original signal by wavelet to obtain wavelet coefficients of multiple scales;

[0073] Threshold processing is performed on the wavelet coefficients of each scale, the coefficients less than a certain threshold are set to 0, and the coefficients greater than or equal to the threshold are retained;

[0074] Perform wavelet reconstruction on the processed wavelet coefficients to obtain the denoised signal;

[0075] Repeat the above steps until the stopping criterion is met.

[0076] The collected data is transmitted to the dispatching center through 5G communication technology to remove duplicate values ​​and outliers. Among them, the 5G network has the advantages of low latency, high bandwidth and high reliability, which can ensure the real-time and accuracy of data transmission.

[0077] Construct a power load distribution prediction model to predict future power load distribution and provide support for grid resource dispatching, including:

[0078] Based on the long short-term memory network, a power load distribution prediction model is constructed; the long short-term memory network adopts the existing network model, which will not be repeated here.

[0079] The power load distribution prediction model is trained to obtain a trained prediction model; wherein the prediction model can be trained using existing model training technology.

[0080] The trained prediction model is deployed to the edge server and cloud server to predict the input load data, transmission power and number of service users to obtain the future power load distribution.

[0081] Among them, the task is executed locally without offloading, and the delay generated

[0082] Indicates the local server ui Task T ik The number of instructions required to complete; Indicates the maximum computing capacity of the terminal device layer server.

[0083] Task local processing energy consumption:

[0084]

[0085] Total consumption of local processing is the sum of delay and energy consumption:

[0086] α is the energy consumption weight;

[0087] Delay in offloading tasks to edge computing layer servers:

[0088] L ie For servers i Maximum transmission rate to edge computing layer servers:

[0089]

[0090] Where S represents the useful signal power, σ 2 is the noise power;

[0091] Energy consumption is the sum of computing energy consumption and transmission energy consumption:

[0092]

[0093] Total consumption:

[0094]

[0095] Delay in offloading tasks to cloud servers:

[0096] Where L ic For servers i Maximum transfer rate to cloud server:

[0097]

[0098] Energy consumption is the sum of computing energy consumption and transmission energy consumption:

[0099]

[0100] Total consumption:

[0101]

[0102] Tasks can be assigned to the cloud computing layer, edge computing layer servers, and terminal device layer servers. Δ=0 means assigned to the terminal device layer server, Δ=1 means assigned to the edge computing layer server, Δ=2 means assigned to the cloud computing layer, and Δ=-1 means the task transmission fails.

[0103] The total cost of the task is:

[0104]

[0105] The overall goal of task offloading is to minimize the total cost of all tasks:

[0106]

[0107] Δ∈{-1,0,1,2}

[0108] Set constraints: 1. The task assigned to the device cannot exceed its maximum computing capacity; 2. The time to execute the task cannot exceed the limited time.

[0109] It should be noted that after receiving the data from each node, the dispatch center processes the data and first analyzes the voltage, current and frequency of each node, especially the comparison of frequency and phase angle. By comparing the frequency fluctuations of each node, the dispatch center can quickly locate the area where the fault or frequency mutation occurs in the power grid. Once a frequency mutation is detected, the dispatch center can identify the fault point, further analyze the cause of the frequency change (such as load mutation, generator set instability, etc.), and determine the node that needs power angle compensation, providing an accurate decision-making basis for subsequent regulation and control.

[0110] In addition, the dispatch center can issue alarm instructions to the inverter to facilitate better frequency control and adjustment. Specifically, real-time monitoring of the dispatch center and the inverter can be established, including the following steps:

[0111] a. Steady-state monitoring of power grid operation

[0112] Steady-state monitoring is a basic function of the smart grid dispatching and control system. It can process various analog quantities and state quantities, support bypass generation, peer generation, state estimation generation and other operations, as well as multi-source data and data quality code processing, and can query telemetry and telesignal sampling. The dynamic topological coloring function of steady-state monitoring for the status of equipment and sections directly affects the operator's judgment of the power grid status, and should be able to be flexibly configured. Steady-state monitoring also needs to support remote control and adjustment of circuit breakers, disconnectors and taps to meet the needs of remote control in power grid operation.

[0113] b. Dynamic monitoring and analysis of power grid operation

[0114] Dynamic monitoring and analysis is an important supplement to steady-state monitoring, and has the ability to compare dynamic and steady-state measurements, identify bad data, define formulas, and provide calculation libraries. It can provide phase angle measurement and calculation, unit operation status monitoring, and support phase angle reference personality settings. In addition, busbar balancing, section monitoring, measurement, and phase angle difference over-limit alarm and shielding functions should be provided.

[0115] c. Online monitoring and analysis of relay protection equipment

[0116] Online monitoring and analysis of relay protection equipment should be able to process in real time the protection equipment status quantity, analog quantity, event / setting / soft pressure plate information, fault recording, etc. as well as abnormal alarm, self-test, action and communication status information, so as to correctly display the operating status and action of the protection equipment, ensure that a fault briefing is given when a fault occurs and provide a comprehensive intelligent alarm.

[0117] d. Online monitoring of safety and stability control devices (systems)

[0118] Online monitoring of safety and stability devices can provide monitoring of device operation modes, such as pressure plate status, allowable cutting status, cuttable load and unit quantity, maximum DC boost and reduction quantity, and other operating mode information as well as channel status, abnormal alarms, device action and other information. It can also provide statistical analysis and event alarms of the action behavior and abnormal status of the safety and control device (system), has an alarm function for insufficient control quantity of the on-duty strategy, and supports calling set values ​​and strategy table description files.

[0119] e. Comprehensive intelligent analysis and alarm

[0120] It can analyze and generate system abnormality alarms such as equipment tripping in the first time, and can also generate protection equipment abnormality alarms in combination with protection information. It can generate power grid operation warnings in combination with network analysis and online safety and stability analysis. It can generate meteorological water situation warnings in combination with hydropower or new energy detection and management systems, and it can generate lightning warning information in combination with lightning positioning systems.

[0121] In this embodiment, the frequency fluctuation is adjusted by power angle compensation control of the inverter, which specifically includes:

[0122] The power angle compensation control of the inverter includes:

[0123] The power angle compensation control transforms the three-phase voltage V abc , three-phase voltage U on the grid side abc Three-phase current I abc Converted to V in dq0 coordinate system d ,V q and I d ,I q ; The phase-locked loop controls V d ,V q and Ud ,U q Perform phase adjustment and obtain the phase angle through the integrator 1 / s; adjust the power angle through the PID controller and output the phase compensation angle δ1; the final phase angle δ is obtained by taking the remainder of δ1 and limiting the compensation phase angle to between positive and negative pi; the phase angle δ is used as the input of the power loop to adjust the phase of the inverter output voltage;

[0124] The voltage loop controls the following: the voltage loop receives the voltage command output by the power loop and the actual voltage v od ,v oq ; By calculating the error and Get the error signal; proportional controller K pv Perform preliminary adjustment on the error signal; the integrator integrates the error signal at 1 / s to generate an integral control signal Voltage feedback control K iv The signal output by the integrator is compared with the actual current i od ,i oq Compare and get the current reference value Generated current reference value As the input of the current loop;

[0125] The current loop control includes: the current loop receives the current reference value directly and the actual current i ld ,i lq ; By calculating the error and The error signal is obtained; the proportional controller Kpc performs preliminary adjustment on the error signal; the integrator 1 / s integrates the error signal to generate an integral control signal γ d ,γ q The current feedback control Kic compares the signal output by the integrator with the output of the voltage loop to obtain the final control voltage The final control voltage As the input of PWM modulation;

[0126] PWM modulation includes: output voltage instruction of current loop Expressed in the dq0 coordinate system; through coordinate transformation, Converted into a three-phase voltage signal in the abc coordinate system; the PWM gain module adjusts the amplitude of the three-phase voltage signal to meet the requirements of the PWM modulation module; the PWM module receives the adjusted three-phase voltage signal and converts it into a PWM signal for controlling power switching devices such as IGBT.

[0127] The voltage loop consists of output voltage current feedback and two PI controllers; F is the current feedback coefficient, Kpv is the proportional gain of the voltage loop PI controller, and Kiv is the integral gain; the integral link output of the two PI controllers They can be expressed by the following differential equations:

[0128]

[0129] Among them, v od * is the power loop d-axis output voltage reference, v od is the power loop d-axis output voltage, v oq * is the power loop q-axis output voltage reference, v oq is the q-axis output voltage of the power loop;

[0130] The voltage loop outputs ild and ilq can be expressed by the following equations:

[0131]

[0132] Among them, i od is the inverter d-axis output current, ω n is the system rated angular frequency, C f is the filter capacitor, i oq is the inverter q-axis output current.

[0133] The current loop is composed of the filter front-stage inductor current feedback and two PI controllers; Kpc is the proportional gain of the current loop PI controller, and Kic is the integral gain; the integral link outputs γd and γq of the two PI controllers can be expressed by the following differential equations:

[0134]

[0135] Among them, i ld * is the reference current of the d-axis of the current loop, i ld is the d-axis current of the current loop, i lq * is the reference current of the current loop q axis, i lq is the q-axis current of the current loop;

[0136] The current loop outputs vid and viq can be expressed by the following equations:

[0137] v id * =-ω n L f i lq +K pc (i ld *-i ld )+K ic γ d

[0138] v iq * =ω n L f i ld +K pc (i lq * -i lq )+K ic γ q

[0139] Among them, K pc is the proportional gain of the current loop PI controller, K ic is the integral gain.

[0140] The specific process of the power ring processing data includes:

[0141] The data input to the power loop includes: the dq component of the voltage v od ,v oq and the dq components of the current i od ,i oq ;

[0142] The power loop is first calculated by the formula p = v od i od +v oq i oq Get the active power P; by calculating the formula q = v oq i od -v od i oq The reactive power Q is obtained; the active power P and the reactive power Q are filtered in the first order to obtain a smooth power signal;

[0143] Active power control is achieved through the equation ω n -m(PP set ) to obtain the phase angle θ, and integrate it through the integrator 1 / s.

[0144] Specifically, the input of the power loop v od 、v oq 、i od 、i oq is the inverter output voltage v o With the output current i o The d and q axis components of the inverter are shown in Figure 2, where δ is the inverter power angle compensation angle. The equation of the first-order filter link is:

[0145]

[0146] Where P is the active power after filtering, ω c is the filter corner frequency, s is the Laplace variable, p is the active power before filtering, Q is the reactive power after filtering, and q is the reactive power before filtering;

[0147] By controlling the power angle and output voltage of the inverter, the active and reactive power can be controlled. The angular frequency is used instead of the power angle to obtain the active-frequency droop equation:

[0148] ω=ω n -m(PP set )

[0149] θ=ω n t-∫m(PP set )dt

[0150] Among them, P is the inverter output active power, P set is the active power given, ω n is the system rated angular frequency, ω is the inverter angular frequency, θ is the inverter phase angle, and m is the droop coefficient.

[0151] The present invention can rapidly adjust the phase angle of the inverter output voltage after a short circuit fault occurs through optimized inverter power angle control and droop control, so that the phase angle difference between the inverter output voltage and the synchronous generator or infinite power grid is quickly reduced to a stable state, thereby greatly shortening the system recovery time.

[0152] By optimizing the control strategy, the voltage and frequency fluctuations during the recovery process are effectively suppressed, the system oscillation is reduced, the power supply quality is improved, and the smooth operation of the power system is ensured. Even when the traditional method fails, the present invention can still maintain high reliability. It is suitable for various complex power system structures, ensuring that the system can operate stably under high load and complex conditions, and enhancing the overall reliability and adaptability of the power system.

[0153] The present invention is not only applicable to synchronous generator models, but also to infinite power grid models, providing a wider range of application scenarios and adapting to the diversified needs of modern power systems. The present invention adopts the data transmission method of 5G signals, which effectively ensures the stability and transmission rate of data transmission, maintains the real-time nature of data changes and adjustments, and ensures a smoother operation of the power system.

[0154] Through the above technical improvements, the present invention has achieved significant technical progress in terms of rapid recovery after a short-circuit fault in the power system, reducing oscillations and improving reliability, and provides an efficient and reliable solution for modern power systems.

[0155] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for adjusting the frequency of a power system based on 5G transmission, characterized in that: include: Collecting electrical characteristic data of each node in the power grid; the electrical characteristic data includes current, voltage and frequency; Analyze and process the collected electrical characteristic data, locate the area where the fault or frequency mutation occurs in the power grid, and identify the fault point; The frequency fluctuation is adjusted through the power angle compensation control of the inverter, so that the frequency of the power grid gradually returns to normal.

2. The method for adjusting the frequency of a power system based on 5G transmission according to claim 1, characterized in that: Collect electrical characteristic data of each node in the power grid, including: A distributed measurement method is adopted, and sensors are installed at each node to collect and monitor current, voltage and frequency in the power system in real time; the sensors include current transformers, voltage transformers and power probes.

3. The method for adjusting the frequency of a power system based on 5G transmission according to claim 1, characterized in that: Analyze and process the collected electrical characteristic data, including: Filter and denoise the collected signals to remove high-frequency noise and interference; The collected data is transmitted to the dispatch center through 5G communication technology to remove duplicate values ​​and abnormal values; Construct a power load distribution prediction model to predict future power load distribution.

4. The method for adjusting the frequency of a power system based on 5G transmission according to claim 3 is characterized in that: Filter and denoise the collected signal, including: Decompose the original signal by wavelet to obtain wavelet coefficients of multiple scales; Threshold processing is performed on the wavelet coefficients of each scale, the coefficients less than a certain threshold are set to 0, and the coefficients greater than or equal to the threshold are retained; Perform wavelet reconstruction on the processed wavelet coefficients to obtain the denoised signal; Repeat the above steps until the stopping criterion is met.

5. The method for adjusting the frequency of a power system based on 5G transmission according to claim 3 is characterized in that: Construct a power load distribution prediction model to predict future power load distribution, including: Based on long short-term memory network, a power load distribution prediction model is constructed; Training the power load distribution prediction model to obtain a trained prediction model; The trained prediction model is deployed to the edge server and cloud server to predict the input load data, transmission power and number of service users to obtain the future power load distribution.

6. The method for adjusting the frequency of a power system based on 5G transmission according to claim 1, characterized in that: The frequency fluctuation is regulated by the power angle compensation control of the inverter, including: The power angle compensation control of the inverter includes: The power angle compensation control transforms the three-phase voltage V abc , three-phase voltage U on the grid side abc Three-phase current I abc Converted to V in dq0 coordinate system d ,V q and I d ,I q ; The phase-locked loop controls V d ,V q and U d ,U q Perform phase adjustment and obtain the phase angle through the integrator 1 / s; adjust the power angle through the PID controller and output the phase compensation angle δ1; the final phase angle δ is obtained by taking the remainder of δ1 and limiting the compensation phase angle to between positive and negative pi; the phase angle δ is used as the input of the power loop to adjust the phase of the inverter output voltage; The voltage loop controls the following: the voltage loop receives the voltage command output by the power loop and the actual voltage v od ,v oq ; By calculating the error and Get the error signal; proportional controller K pv Perform preliminary adjustment on the error signal; the integrator integrates the error signal at 1 / s to generate an integral control signal Voltage feedback control K iv The signal output by the integrator is compared with the actual current i od ,i oq Compare and get the current reference value Generated current reference value As the input of the current loop; The current loop control includes: the current loop receives the current reference value directly and the actual current i ld ,i lq ; By calculating the error and The error signal is obtained; the proportional controller Kpc performs preliminary adjustment on the error signal; the integrator 1 / s integrates the error signal to generate an integral control signal γ d ,γ q The current feedback control Kic compares the signal output by the integrator with the output of the voltage loop to obtain the final control voltage The final control voltage As the input of PWM modulation; PWM modulation includes: output voltage instruction of current loop Expressed in the dq0 coordinate system; through coordinate transformation, Converted into a three-phase voltage signal in the abc coordinate system; the PWM gain module adjusts the amplitude of the three-phase voltage signal to meet the requirements of the PWM modulation module; the PWM module receives the adjusted three-phase voltage signal and converts it into a PWM signal for controlling power switching devices such as IGBT.

7. The method for adjusting the frequency of a power system based on 5G transmission according to claim 6, characterized in that: The voltage loop consists of output voltage current feedback and two PI controllers; F is the current feedback coefficient, Kpv is the proportional gain of the voltage loop PI controller, and Kiv is the integral gain; the integral link output of the two PI controllers They can be expressed by the following differential equations: Among them, v od * is the power loop d-axis output voltage reference, v od is the power loop d-axis output voltage, v oq * is the power loop q-axis output voltage reference, v oq is the q-axis output voltage of the power loop; The voltage loop outputs ild and ilq can be expressed by the following equations: Among them, i od is the inverter d-axis output current, ω n is the system rated angular frequency, C f is the filter capacitor, i oq is the inverter q-axis output current.

8. The method for adjusting the frequency of a power system based on 5G transmission according to claim 6, characterized in that: The current loop is composed of the filter front-stage inductor current feedback and two PI controllers; Kpc is the proportional gain of the current loop PI controller, and Kic is the integral gain; the integral link outputs γd and γq of the two PI controllers can be expressed by the following differential equations: Among them, i ld * is the d-axis reference current of the current loop, i ld is the d-axis current of the current loop, i lq * is the reference current of the current loop q axis, i lq is the q-axis current of the current loop; The current loop outputs vid and viq can be expressed by the following equations: v id * =-ω n L f i lq +K pc (i ld * -i ld )+K ic γ d v iq * =ω n L f i ld +K pc (i lq * -i lq )+K ic γ q Among them, K pc is the proportional gain of the current loop PI controller, K ic is the integral gain.

9. The method for adjusting the frequency of a power system based on 5G transmission according to claim 6, characterized in that: The specific process of power ring processing data includes: The data input to the power loop includes: the dq component of the voltage v od ,v oq and the dq components of the current i od ,i oq ; The power loop is first calculated by the formula p = v od i od +v oq i oq Get the active power P; by calculating the formula q = v oq i od -v od i oq The reactive power Q is obtained; the active power P and the reactive power Q are filtered in the first order to obtain a smooth power signal; Active power control is achieved through the equation ω n -m(PP set ) to obtain the phase angle θ, and integrate it through the integrator 1 / s.

10. The method for adjusting the frequency of a power system based on 5G transmission according to claim 9, characterized in that: Power loop input v od 、v oq 、i od 、i oq is the inverter output voltage v o With the output current i o The d and q axis components of the inverter are shown in Figure 2, where δ is the inverter power angle compensation angle. The equation of the first-order filter link is: Where P is the active power after filtering, ω c is the filter corner frequency, s is the Laplace variable, p is the active power before filtering, Q is the reactive power after filtering, and q is the reactive power before filtering; By controlling the power angle and output voltage of the inverter, the active and reactive power can be controlled. The angular frequency is used instead of the power angle to obtain the active-frequency droop equation: oh = oh n -m(PP set ) θ=ω n t-∫m(P-P set )dt Among them, P is the inverter output active power, P set is the active power given, ω n is the system rated angular frequency, ω is the inverter angular frequency, θ is the inverter phase angle, and m is the droop coefficient.

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