Intelligent voltage regulating system and equipment for low-voltage treatment of distribution network area

Abstract

The invention relates to the technical field of power distribution network line regulation, and discloses an intelligent voltage regulation system and equipment for low-voltage treatment of a power distribution network area, and the system comprises a collection filtering unit which is used for collecting the initial voltage of a power distribution line at the tail end of the area, and carrying out the filtering processing of the initial voltage, and obtaining an intermediate voltage; the voltage regulation and control unit is used for obtaining a corresponding regulation and control voltage according to the voltage value data of the intermediate voltage and outputting the regulation and control voltage to an electric terminal; the backup protection unit is used for preventing the regulation and control voltage from exceeding a voltage threshold value; the data transmission unit is used for transmitting voltage value data of the intermediate voltage and the regulation and control voltage; and the pushing unit is used for receiving and displaying the voltage value data of the intermediate voltage and the regulation and control voltage and sending a parameter regulation signal to the voltage regulation and control unit so as to regulate the regulation and control parameters of the voltage regulation and control unit. The terminal voltage of the transformer area can be monitored in real time.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution network line regulation, and in particular to an intelligent voltage regulation system and equipment for low voltage management in distribution network substations. Background Art

[0002] As the main component of the power supply system, my country's distribution network lines often exist in a single-radiation, long-distance, heavy-load mode. With the rapid growth of electricity consumption, the power supply radius of rural power lines has also increased. The distribution of substations often exceeds the reasonable power supply radius. The phenomenon of low voltage in rural areas has become increasingly prominent, seriously affecting the normal power supply of residents.

[0003] At present, in order to solve the above problems, in the existing technology, the low voltage to households caused by the long power supply radius and small wire diameter of the low-voltage line in the substation area is often treated by adding a phase line to the low-voltage single-phase line, changing the low-voltage single-phase line to three-phase four-wire, increasing the wire diameter, etc.; the low voltage to households caused by heavy overload or seasonal load in the substation area is often treated by changing the load in the adjacent substation area, increasing the capacity of the distribution transformer, or adding a new distribution transformer. However, these methods have the disadvantages of high transformation cost, long construction period, wide power outage range, and inability to flexibly adjust the voltage of the distribution network substation directly point to point. Summary of the invention

[0004] The present invention provides an intelligent voltage regulation system and equipment for low voltage management in distribution network areas to solve the above-mentioned related problems.

[0005] The present invention is achieved through the following technical solutions:

[0006] An intelligent voltage regulation system for low voltage management in distribution network areas, comprising:

[0007] The collecting and filtering unit is used to collect the initial voltage on the power distribution line at the end of the substation, and filter the initial voltage to obtain the intermediate voltage;

[0008] A voltage control unit, used for obtaining a corresponding control voltage according to the voltage value data of the intermediate voltage, and outputting the control voltage to the power terminal;

[0009] A backup protection unit, used to prevent the regulated voltage from exceeding a voltage threshold;

[0010] A data transmission unit, used for transmitting voltage value data of the intermediate voltage and the regulation voltage;

[0011] The push unit is used to receive and display the voltage value data of the intermediate voltage and the regulated voltage, and at the same time, send a parameter adjustment signal to the voltage regulation unit to adjust the regulation parameters of the voltage regulation unit.

[0012] As an optimization, the acquisition filter unit is an active filter or a passive filter.

[0013] As an optimization, the backup protection unit is one or more of a varistor, a transient voltage suppressor, and a thyristor.

[0014] As an optimization, the voltage control unit is a fuzzy neural network voltage and current dual-loop decoupling control model, and the specific structure of the fuzzy neural network voltage and current dual-loop decoupling control model includes:

[0015] A difference change rate calculation unit, used to obtain the difference between the regulated voltage and the preset voltage and the change rate of the intermediate voltage;

[0016] The fuzzy neural network unit is used to fuzzify the difference and the rate of change, input the fuzzified difference and the rate of change into the inference engine which uses the neural network as the fuzzy reasoning and memory fuzzy rules, and then clarify the obtained fuzzy result and output the control parameter K of the PID controller. p , K i , K d ;

[0017] A voltage-current dual-loop decoupling controller is a PID controller, which is used to output adjustment data according to the difference;

[0018] A series-parallel compensation system, used to compensate the adjustment data to obtain a regulated voltage;

[0019] A voltage acquisition system is used to acquire the regulated voltage output by the series-parallel compensation system and transmit the regulated voltage to the difference change rate calculation unit.

[0020] As an optimization, the data transmission unit is a wireless network.

[0021] As an optimization, the push unit includes one or more of a local terminal, a mobile APP, and a web system.

[0022] As an optimization, a bypass maintenance unit is also included, which forms a bypass relationship with the series link of the collection and filtering unit, the backup protection unit, the voltage control unit, the data transmission unit, and the push unit. The input and output ends of the bypass unit are both connected to the distribution line at the end of the substation, and the input end of the bypass unit is located upstream of the collection and filtering unit, and the output end of the bypass maintenance unit is located downstream of the voltage control unit.

[0023] As an optimization, the bypass maintenance unit includes a manual maintenance bypass and an automatic static bypass.

[0024] The present invention also discloses an intelligent voltage regulating device for low voltage management in a distribution network substation, comprising a detachable metal chassis shell, a PCB board is fixedly arranged in the metal chassis shell, and the PCB board is provided with the aforementioned intelligent voltage regulating system for low voltage management in a distribution network substation. The metal chassis shell is also provided with an interface for connecting the distribution line at the end of the substation with the collection and filtering unit and the voltage control unit.

[0025] As an optimization, heat dissipation holes are arranged through the metal chassis shell, and a heat dissipation fan is arranged on the top inner side of the metal chassis shell, the area of ​​the first opening of the heat dissipation hole located on the outside of the side wall of the metal chassis shell is smaller than the second opening of the heat dissipation hole located on the inner side of the metal chassis shell, and the line between the first opening and the second opening is a downwardly concave broken line, and the upper end of the first opening is lower than the lower end of the second opening; and the size of the cross-section from the first opening to the second opening changes to gradually increase and then decrease, and the cross-section between the broken line between the first opening and the second opening is the largest.

[0026] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0027] The intelligent voltage regulation system of the present invention can monitor the voltage at the end of the substation in real time, and transmit the monitored voltage information to the remote terminal, so that the entire substation end has the ability to remotely regulate low voltage;

[0028] The intelligent voltage regulation system of the present invention is used to intelligently regulate the terminal voltage of the distribution network substation and compensate for the low voltage at the terminal of the substation, so as to achieve the purpose of quickly regulating the terminal voltage to a qualified voltage range. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0030] Figure 1 This is a schematic diagram of module connections of an intelligent voltage regulation system for low voltage management in a distribution network area according to the present invention;

[0031] Figure 2 It is a structural schematic diagram of a metal chassis shell with a cooling fan;

[0032] Figure 3 It is the schematic diagram of the equivalent circuit of the parallel model;

[0033] Figure 4 It is the schematic diagram of the equivalent circuit of the series model;

[0034] Figure 5 This is a schematic diagram of the structure of the fuzzy neural network voltage and current dual-loop decoupling control model of the present invention;

[0035] Figure 6 It is a structural schematic diagram of the installation position of the bypass maintenance unit;

[0036] Figure 7 The figure is a schematic diagram of voltage statistics of the end users in the substation area after the intelligent voltage regulating device of the present invention is installed.

[0037] Marks and corresponding parts names in the attached drawings:

[0038] 1-metal chassis shell, 2-cooling fan, 3-cooling hole, 3a-first hole, 3b-second hole. DETAILED DESCRIPTION

[0039] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0040] This embodiment 1 provides an intelligent voltage regulation system for low voltage management in distribution network areas. Figure 1 As shown, including:

[0041] The collecting and filtering unit is used to collect the initial voltage on the power distribution line at the end of the substation, and filter the initial voltage to obtain the intermediate voltage;

[0042] A voltage control unit, used for obtaining a corresponding control voltage according to the voltage value data of the intermediate voltage, and outputting the control voltage to the power terminal;

[0043] A backup protection unit, used to prevent the regulated voltage from exceeding a voltage threshold;

[0044] A data transmission unit, used for transmitting voltage value data of the intermediate voltage and the regulation voltage;

[0045] The push unit is used to receive and display the voltage value data of the intermediate voltage and the regulated voltage, and at the same time, send a parameter adjustment signal to the voltage regulation unit to adjust the regulation parameters of the voltage regulation unit.

[0046] In this technical solution, after the voltage signal is collected and filtered and the logic judgment is completed through the voltage collection and filtering unit and the voltage control unit, the information before and after the voltage regulation is fed back to the remote terminal (push unit) through the wireless network in the data transmission unit. The voltage regulation unit can be adjusted by parameter setting on the remote terminal, and the backup protection unit can prevent large voltage input from causing circuit damage or system failure. Through the intelligent voltage regulation system of the present invention, remote real-time monitoring of low voltage in the substation area can be achieved.

[0047] Next, each unit will be introduced in detail.

[0048] The function of the acquisition and filtering unit is to accurately collect the line voltage and filter out noise, thus improving the accuracy of the intelligent voltage regulation system. By comparing the signal-to-noise ratios of the active filter and the digital filter, the active filter with a higher signal-to-noise ratio was selected as the acquisition and filtering unit of the low-voltage intelligent voltage regulation device.

[0049] The function of the control unit is to improve the response speed of the system and shorten the voltage control time at the end of the distribution network. By comparing the model response time of the fuzzy voltage and current dual-loop decoupling control model, the neural network voltage and current dual-loop decoupling control model, and the fuzzy neural network voltage and current dual-loop decoupling control model, the fuzzy neural network voltage and current dual-loop decoupling control model with a shorter response time was selected as the control unit of the low-voltage intelligent voltage regulation device.

[0050] The specific structure of the fuzzy neural network voltage and current dual-loop decoupling control model includes:

[0051] A difference change rate calculation unit, used to obtain the difference between the regulated voltage and the preset voltage and the change rate of the intermediate voltage;

[0052] The fuzzy neural network unit is used to fuzzify the difference and the rate of change, input the fuzzified difference and the rate of change into the inference engine which uses the neural network as the fuzzy reasoning and memory fuzzy rules, and then clarify the obtained fuzzy result and output the control parameter K of the PID controller. p , K i , K d ;

[0053] A voltage-current dual-loop decoupling controller is a PID controller, which is used to output adjustment data according to the difference;

[0054] A series-parallel compensation system, used to compensate the adjustment data to obtain a regulated voltage;

[0055] A voltage acquisition system is used to acquire the regulated voltage output by the series-parallel compensation system and transmit the regulated voltage to the difference change rate calculation unit.

[0056] The fuzzy neural network voltage and current dual-loop decoupling control model consists of two parts: the voltage and current dual-loop decoupling controller and the fuzzy neural network. The basic idea is to achieve parameter control through continuous iteration, combine fuzzy control with neural network to form a fuzzy neural network, and then combine the voltage and current dual-loop decoupling control algorithm to obtain the fuzzy neural network voltage and current dual-loop decoupling control model, which has better dynamic control capabilities.

[0057] The voltage-current dual-loop decoupling control algorithm includes two links, namely the parallel link and the series link.

[0058] The two links of the voltage and current dual-loop decoupling control algorithm correspond to Figure 5 The decoupling fuzzy unit in the box, that is, at the output end of the fuzzy neural network structure, outputs the three control parameters of the PDI controller after passing through the series-parallel links.

[0059] (1) Mathematical model of parallel link

[0060] The parallel link adopts a typical voltage source converter, and its equivalent circuit is as follows Figure 3 As shown (taking single-phase circuit as an example), u sa is the grid phase voltage, L1 and R1 are the grid-side equivalent inductance and internal resistance respectively, C dc is the DC capacitance of the voltage source converter, u dc is the DC bus voltage.

[0061] According to Kirchhoff's voltage and current laws, the general mathematical model of the parallel link is:

[0062]

[0063] The mathematical model in the synchronously rotating dq coordinate system is:

[0064]

[0065] Where ω is the synchronous rotation angular velocity, u sd and u sq The grid voltage u sa 、u sb and u sc The dq component in the dq coordinate system; u 1d and u 1q is the parallel link voltage u 1a 、u 1b and u 1c dq component in the dq coordinate system; i sd and i sq is the grid-side equivalent inductance current i of the parallel link sa 、i sb and i sc The dq component in the dq coordinate system.

[0066] (2) Mathematical model of series connection

[0067] The series link and the parallel link share the DC bus, the equivalent circuit of the series link Figure 4 (Take the single-phase circuit as an example). L2 and R2 are the filter inductor and its internal resistance respectively; C2 is the series link filter capacitor; u 2ais the compensation voltage of the series link; i La is the filter inductor current; i pa is the output current; u pa is the output voltage of the series link.

[0068] When only the three-phase balance is considered and the line and switch losses are ignored, the mathematical model of the series link in the synchronous rotating dq coordinate system is:

[0069]

[0070] Among them, u pd and u pq They are the series link output voltage u pd and u pq dq component in the dq coordinate system; i Ld and i Lq They are the series link filter inductor current i sa 、i sb and i sc The dq component in the dq coordinate system; u 2d and u 2q They are the series link compensation voltage u 2a 、u 2b and u 2c dq component in the dq coordinate system; i pd and i pq They are the series link output current i pa 、i pb and i pc The dq component in the dq coordinate system.

[0071] The series link is connected after the parallel link.

[0072] Design a voltage and current dual-loop decoupling controller schematic based on fuzzy neural network, such as Figure 5 As shown in Figure 2, r(k) is the preset voltage and y(k) is the regulation voltage.

[0073] The difference between the terminal voltage measurement value and the set value and its rate of change are used as two input quantities of the fuzzy neural network for fuzzification processing. The fuzzified parameters are input into the inference engine of the neural network as the fuzzy reasoning and memory fuzzy rules, and then the fuzzy results are clarified and output as the control parameter K. p , K i , K d Finally, the voltage compensation system is controlled through the voltage-current dual-loop decoupling controller, thereby realizing the control of the terminal voltage of the distribution network area.

[0074] The series-parallel compensation control principle is used to realize the intelligent regulation of low voltage in the distribution area. The voltage-current dual-loop decoupling control model is designed and applied to the compensation control of the intelligent voltage regulating device in the distribution network area to achieve the purpose of intelligent voltage regulation and ensure that the voltage value of the end user in the distribution network area is within the qualified voltage range throughout the day.

[0075] The function of the backup protection unit is to prevent circuit damage or system failure caused by large voltage input, and to improve the stability and reliability of the system. By comparing the robustness of the three solutions of varistor, transient voltage suppressor and thyristor, the thyristor solution with lower robustness was selected as the backup protection unit of the low-voltage intelligent voltage regulator.

[0076] The function of the voltage control unit is to improve the response speed of the system and shorten the voltage control time at the end of the distribution network. By comparing the model response time of the fuzzy voltage and current dual-loop decoupling control model, the neural network voltage and current dual-loop decoupling control model, and the fuzzy neural network voltage and current dual-loop decoupling control model, the fuzzy neural network voltage and current dual-loop decoupling control model with a shorter response time was selected as the control unit of the low-voltage intelligent voltage regulation device.

[0077] The function of the data transmission unit is to transmit the data of the low-voltage intelligent voltage regulator in real time and accurately remotely. By comparing the network transmission speed and data loss rate of the GPRS network and the 5G network, the 5G network with faster network transmission speed and lower data loss rate was selected as the communication unit of the low-voltage intelligent voltage regulator.

[0078] The function of the push unit is to realize the information interaction between the operator and the remote monitoring system and the intelligent voltage regulation system. The data push accuracy, development cycle, development cost, safety risk, and usage scenarios of the local terminal, mobile APP, and web system are compared. The comparison results show that the local terminal has the risk of electric shock and falling from heights during debugging, and the web system has the problems of long development cycle and high development cost, and the usage scenarios of the two are single. Therefore, the mobile APP solution was selected as the push unit of the low-voltage intelligent voltage regulation device.

[0079] In some embodiments, a bypass maintenance unit is also included that forms a bypass relationship with the series link of the collection and filtering unit, the backup protection unit, the voltage control unit, the data transmission unit, and the push unit. The input and output ends of the bypass unit are both connected to the transmission line at the end of the substation, and the input end of the bypass unit is located upstream of the collection and filtering unit, and the output end of the bypass maintenance unit is located downstream of the voltage control unit.

[0080] The function of the bypass maintenance unit is to reduce the loss of the device when the device does not need voltage regulation; when the device fails or needs maintenance, the device is bypassed to ensure normal power supply to users. The automatic switching capability, switching time, and operation accuracy of the automatic static bypass and manual maintenance bypass solutions are compared. The comparison results show that the automatic static bypass is convenient for automated management and remote operation, and the manual maintenance bypass focuses on providing more control flexibility and higher reliability, but the usage scenarios of both solutions have limitations. Therefore, the bypass maintenance unit of the low-voltage intelligent voltage regulating device chooses the automatic static bypass + manual maintenance bypass solution.

[0081] The preparation process of the bypass maintenance unit is as follows:

[0082] The maintenance bypass is independently made according to the purchased electronic components. When the equipment is lightly loaded (5A and below) or unloaded, the equipment is automatically in the bypass direct state; when the equipment is heavily loaded (greater than 5A current), the equipment is in the running state, and the grid voltage is boosted to the "voltage target value"; after the input grid voltage is 5V higher than the "voltage target value", after another 3 minutes, the equipment will switch from the boost state to the standby state, and the bypass contactor will be closed. At this time, the device has only a dozen W of standby power consumption to reduce device losses; when a fault occurs or maintenance is required, the device can be automatically or manually bypassed to ensure normal power consumption for users. The installation diagram is as follows Figure 6 shown.

[0083] 1. Manually switch to maintenance bypass mode

[0084] Close the built-in maintenance bypass switch of the UPS, adjust the maintenance bypass from the open state to the closed state, and confirm that there is no abnormality in the system.

[0085] 2. Introduction to maintenance bypass

[0086] The main function of the maintenance bypass is to switch the load equipment from the output end of the UPS to the maintenance bypass when the UPS (uninterruptible power supply) needs maintenance or repair, so as to achieve uninterrupted power supply. This ensures that during the UPS maintenance period, the load equipment can still operate normally and will not be affected by the power failure of the UPS. At the same time, the maintenance bypass can also provide electrical isolation to ensure the safety of maintenance personnel.

[0087] 3. How to use maintenance bypass (detailed)

[0088] 1). Switch to static bypass: Before switching the UPS to maintenance bypass, you first need to switch the UPS to static bypass mode. This step is usually performed through the UPS control panel or software. In static bypass mode, the UPS inverter stops working, and the AC power directly supplies power to the load through the static bypass switch.

[0089] 2). Close the maintenance bypass switch: After confirming that the UPS has switched to static bypass mode, you can close the maintenance bypass switch. This step usually requires the use of a special key or tool to ensure that only authorized personnel can operate it. After closing the maintenance bypass switch, the load equipment will obtain power supply through the maintenance bypass.

[0090] 3). Disconnect the UPS input and output switches: After closing the maintenance bypass switch, you need to disconnect the UPS input and output switches to ensure that the UPS is completely isolated from the mains and load equipment. This ensures that during the maintenance process, the UPS will not accidentally restart or affect the load equipment.

[0091] 4) Perform maintenance or repair work: After completing the above steps, you can perform maintenance or repair work on the UPS. During the maintenance process, the load equipment will obtain power supply through the maintenance bypass and will not be affected by the power outage of the UPS.

[0092] 5) Restore normal operation: After the maintenance or repair work is completed, you need to follow the reverse steps to restore the UPS to normal operation. First, close the input and output switches of the UPS, then disconnect the maintenance bypass switch, and finally switch the UPS back to normal operation mode.

[0093] Next, the feasibility test of the above units was carried out to verify the feasibility of the proposed overall technical solution by designing and building a corresponding experimental platform. The experimental results are as follows:

[0094] 1) The voltage acquisition and filtering unit uses a resistor voltage divider voltage acquisition circuit and a second-order active low-pass filter circuit. After collecting the actual voltage at the data acquisition monitoring point, 20 field experiments were conducted on the second-order active low-pass filter circuit, and the waveform after filtering was observed using an oscilloscope to calculate the total voltage distortion rate. The test results show that the total voltage distortion rate of the second-order active low-pass filter circuit is less than 5%, meeting the implementation target requirements.

[0095] 2) The bypass maintenance unit selects automatic static bypass + manual maintenance bypass. The maintenance bypass is made, and a large current generator is used to provide a constant large current of 600A. The maintenance bypass is subjected to 10 load short-circuit tests. The test results show that the load short-circuit test bearing time is 1.37s, which meets the implementation target requirements.

[0096] 3) The backup protection unit uses thyristor. Design the thyristor overvoltage protection circuit, solder the circuit board, connect the fixed reference voltage 6V to the reverse input of the thyristor overvoltage protection, use the signal generator to input 10 random voltages, check the conduction of the thyristor, the action of the protection circuit, and calculate the success rate of overvoltage protection. The test results show that the overvoltage protection success rate of the thyristor overvoltage protection circuit is 100%, meeting the implementation target requirements.

[0097] 4) The control unit adopts a fuzzy neural network voltage and current dual-loop decoupling control model. Design a fuzzy neural network voltage and current dual-loop decoupling control model, build a simulation model in Simulink software, give a current sine wave signal and apply a voltage change at 0.3s, conduct 10 experiments, and calculate the system robustness. The test results show that the robustness of the fuzzy neural network voltage and current dual-loop decoupling control model is 0.16%, which meets the implementation target requirements.

[0098] 5) The communication unit uses a 5G network. Design a 5G communication network circuit, randomly select 10 device installation locations to upload large files through the FTP tool, and use traffic software to test network latency. The test results show that the 5G network latency is 19.6ms, meeting the implementation target requirements.

[0099] 6) The push unit selects a mobile APP. Write the APP software, enter the device information, set the boost compensation mode, select the startup mode, enter the voltage target value and voltage threshold value of phase A, phase B, and phase C, set the corresponding parameters according to the actual situation, and conduct 20 groups of message reception time and reception success rate experiments. The test results show that the voltage display, alarm parameter display, and background recording operation interface are all normal, the message reception time is 0.93s, and the APP message reception success rate is 100%, meeting the implementation target requirements.

[0100] 7) The metal chassis shell is made of aluminum alloy. The aluminum alloy chassis is made, and 20 chassis shell humidity tests and salt spray corrosion tests are carried out in rainy weather. The weight loss method is used to calculate the corrosion rate within ten days. The test results show that the humidity of the aluminum alloy chassis shell is 31.5% RH on rainy days, and the corrosion rate within ten days is 1.5mg / cm 2 .d. Achieve implementation target requirements.

[0101] Example 2 also discloses an intelligent voltage regulating device for low voltage management in a distribution network substation, comprising a detachable metal chassis shell 1, in which a PCB board is fixedly arranged, and on which an intelligent voltage regulating system for low voltage management in a distribution network substation as described in any one of claims 1 to 8 is arranged, and the metal chassis shell 1 is also provided with an interface for connecting the distribution line at the end of the substation with the collection and filtering unit and the voltage control unit.

[0102] The function of the metal chassis shell 1 is to improve the adaptability of the voltage regulating device to complex on-site environments and increase the on-site life of the voltage regulating device. By comparing the deformation ratios of the aluminum alloy case and the stainless steel case under the same pressure, the aluminum alloy case with the smallest deformation ratio is selected as the chassis shell of the low-voltage intelligent voltage regulating device.

[0103] In some embodiments, Figure 2 As shown, a heat dissipation hole 3 is arranged through the metal chassis shell 1, a heat dissipation fan 2 is arranged on the inner top of the metal chassis shell 1, the heat dissipation fan 2 is embedded on the top wall of the metal chassis shell 1, and a filter is arranged at the input end (air inlet) of the heat dissipation fan 2 for dust prevention.

[0104] The area of ​​the first opening 3a of the heat dissipation hole 3 located on the outside of the side wall of the metal chassis shell 1 is smaller than that of the second opening 3b of the heat dissipation hole 3 located on the inside of the metal chassis shell 1, and the line between the first opening 3a and the second opening 3b is a downwardly concave fold line, and the upper end of the first opening 3a is lower than the lower end of the second opening 3b; and the size of the cross-section from the first opening 3a to the second opening 3b changes to gradually increase and then decrease, and the cross-section between the fold line between the first opening 3a and the second opening 3b is the largest.

[0105] The air in the metal chassis shell 1 passes through the second orifice 3b which is larger than the first orifice 3a. Since the area of ​​the first orifice 3a is smaller than that of the second orifice 3b, the wind speed at the first orifice 3a will be higher than the wind speed at the second orifice 3b. This makes it extremely difficult for dust at the first orifice 3a to enter the metal chassis shell 1 through the heat dissipation hole 3. At the same time, since the cross-sectional area at the fold line is the largest, the resistance of the air in the metal chassis shell 1 entering the heat dissipation hole 3 from the second orifice 3b can be reduced, so that the heat dissipation effect of the metal chassis shell 1 is better. The heat dissipation hole 3 is set as a fold line, and the upper end of the first orifice 3a is lower than the lower end of the second orifice 3b, which can also prevent external dust from directly entering the metal chassis shell 1.

[0106] In order to further verify the practical application effect of the low-voltage intelligent voltage regulating device, the present invention is based on the device design diagram ( Figure 7 ) The seven functional modules are assembled and after the assembly is completed, the device is tested for joint debugging.

[0107] Table 1 Joint debugging test table

[0108] Serial number Completion Whether the requirements are met 1 Wiring correctness 100% satisfy 2 Voltage acquisition sensitivity 100% satisfy 3 Equipment working rate is 100% satisfy 4 APP data transmission accuracy 100% satisfy 5 Equipment voltage regulation success rate 100% satisfy

[0109] After the system safety and reliability were verified and approved, the developed equipment was installed in 20 low-voltage areas. Within 3 months, 3 days were randomly selected to sample and count the voltage data of the end users of the 20 areas throughout the day. Figure 3 shown.

[0110] Statistical data show that the voltage value of the end-users in the distribution network area is in the range of 198V to 230V throughout the day, which meets the national standard and the requirement of 100% qualified voltage value of the end-users in the distribution network area. The device reduces the capital cost of the transformation of the area, solves the problems of long construction period of the transformation of the area, wide power outage range, and inability to flexibly adjust the voltage of the distribution network area directly from point to point, which is conducive to improving the safe and stable operation of the distribution network area.

[0111] Next, the present invention will be described again by using specific examples.

[0112] Case: Installed on 20 low-voltage stations in Renshou County for testing

[0113] 1) Randomly select three days within three months to sample and count the voltage data of the end users in 20 substations throughout the day;

[0114] 2) Determine whether the sampled data is within the qualified voltage range of 198V to 235.4V;

[0115] 3) Calculate the low voltage regulation pass rate of 20 substations.

[0116] From June to August 2024, the device achieved uninterrupted operation in 20 low-voltage substations. The team randomly selected three days and sampled and counted the voltage data of the 20 substation terminal users throughout the day. The voltage conditions of the substation terminal users throughout the day are shown in Table 2. The low voltage situation has been greatly improved, meeting the requirement that the voltage value at the end of the distribution network substation is within the qualified voltage range throughout the day.

[0117] Table 2 Statistics of voltage situation of end users in the intelligent voltage regulation device area

[0118]

[0119]

[0120]

[0121]

[0122] It can be seen that the intelligent voltage regulating device in the distribution network substation was successfully applied in the field experiment. The voltage value of the terminal users in the distribution network substation is in the range of 198V to 230V throughout the day, which is in line with the national standards and meets the company's requirements to control the voltage value of the terminal users in the distribution network substation within the qualified voltage range of 198V to 235.4V throughout the day, so that the qualified rate of the voltage value of the terminal users in the distribution network substation is 100%.

[0123] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An intelligent voltage regulation system for low voltage management in distribution network areas, characterized in that: include: The collecting and filtering unit is used to collect the initial voltage on the power distribution line at the end of the substation, and filter the initial voltage to obtain the intermediate voltage; A voltage control unit, used for obtaining a corresponding control voltage according to the voltage value data of the intermediate voltage, and outputting the control voltage to the power terminal; A backup protection unit, used to prevent the regulated voltage from exceeding a voltage threshold; A data transmission unit, used for transmitting voltage value data of the intermediate voltage and the regulation voltage; The push unit is used to receive and display the voltage value data of the intermediate voltage and the regulated voltage, and at the same time, send a parameter adjustment signal to the voltage regulation unit to adjust the regulation parameters of the voltage regulation unit.

2. According to claim 1, an intelligent voltage regulation system for low voltage management in distribution network areas is characterized in that: The acquisition filter unit is an active filter or a passive filter.

3. The intelligent voltage regulation system for low voltage management in distribution network area according to claim 1 is characterized in that: The backup protection unit is one or more of a varistor, a transient voltage suppressor, and a thyristor.

4. The intelligent voltage regulation system for low voltage management in distribution network area according to claim 1 is characterized in that: The voltage control unit is a fuzzy neural network voltage and current dual-loop decoupling control model, and the specific structure of the fuzzy neural network voltage and current dual-loop decoupling control model includes: A difference change rate calculation unit, used to obtain the difference between the regulated voltage and the preset voltage and the change rate of the intermediate voltage; The fuzzy neural network unit is used to fuzzify the difference and the rate of change, input the fuzzified difference and the rate of change into the inference engine which uses the neural network as the fuzzy reasoning and memory fuzzy rules, and then clarify the obtained fuzzy result and output the control parameter K of the PID controller. p , K i , K d ; A voltage-current dual-loop decoupling controller is a PID controller, which is used to output adjustment data according to the difference; A series-parallel compensation system, used to compensate the adjustment data to obtain a regulated voltage; A voltage acquisition system is used to acquire the regulated voltage output by the series-parallel compensation system and transmit the regulated voltage to the difference change rate calculation unit.

5. The intelligent voltage regulation system for low voltage management in distribution network area according to claim 1 is characterized in that: The data transmission unit is a wireless network.

6. The intelligent voltage regulation system for low voltage management in distribution network area according to claim 1 is characterized in that: The push unit includes one or more of a local terminal, a mobile APP, and a web page system.

7. An intelligent voltage regulation system for low voltage management in distribution network areas according to any one of claims 1 to 6, characterized in that: It also includes a bypass maintenance unit that forms a bypass relationship with the series link of the collection and filtering unit, the backup protection unit, the voltage control unit, the data transmission unit, and the push unit. The input and output ends of the bypass unit are both connected to the distribution line at the end of the substation, and the input end of the bypass unit is located upstream of the collection and filtering unit, and the output end of the bypass maintenance unit is located downstream of the voltage control unit.

8. The intelligent voltage regulation system for low voltage management in distribution network area according to claim 7 is characterized in that: The bypass maintenance unit includes a manual maintenance bypass and an automatic static bypass.

9. An intelligent voltage regulating device for low voltage management in distribution network areas, characterized in that: It comprises a detachable metal chassis shell, in which a PCB board is fixedly arranged, on which an intelligent voltage regulation system for low voltage management in a distribution network substation as described in any one of claims 1 to 8 is arranged, and the metal chassis shell is also provided with an interface for connecting the distribution line at the end of the substation with the collection and filtering unit and the voltage control unit.

10. The intelligent voltage regulating device for low voltage management in distribution network area according to claim 9, characterized in that: Heat dissipation holes are arranged through the metal chassis shell, and a heat dissipation fan is arranged on the top of the inner side of the metal chassis shell. The area of ​​the first opening of the heat dissipation hole located on the outside of the side wall of the metal chassis shell is smaller than the second opening of the heat dissipation hole located on the inner side of the metal chassis shell, and the line between the first opening and the second opening is a downwardly concave broken line, and the upper end of the first opening is lower than the lower end of the second opening; and the size of the cross section from the first opening to the second opening changes to gradually increase and then decrease, and the cross section between the broken line between the first opening and the second opening is the largest.

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