A control method and system of an active power distribution network voltage regulator

Abstract

The application discloses a control method and system of an active power distribution network voltage regulator controller, and the method comprises the following steps: firstly, when the controller is started, it is judged whether the voltage regulator is in a normal operation state, and the circuit breaker and the tap switch are set to be locked; system parameters are read, and a timing interrupt is set; a relay protection judgment and a state monitoring judgment process are performed; it is judged whether output overvoltage fault processing is needed; if no output overvoltage phenomenon occurs, a voltage regulator upshift or downshift control process is entered; if output overvoltage fault occurs, output overvoltage fault processing is performed; after the voltage regulator upshift or downshift control process is entered, the controller judges the current power flow direction of the line, and according to the power flow direction judgment result and the comparison result of the current output voltage and the set voltage, an upshift or downshift instruction is sent to the tap switch. The application realizes centralized and integrated design of relay protection, operation state detection and voltage regulation instruction of the voltage regulating transformer.

Description

Technical Field

[0001] This invention belongs to the field of power distribution network technology, and specifically relates to a control method and system for an active power distribution network voltage regulator controller. Background Technology

[0002] For distribution networks, line voltage regulators and reactive power compensation devices can effectively regulate line voltage and control power quality, especially suitable for distribution networks with long lines and high loads. However, due to the lag in mechanical operation, traditional control response measures (on an hourly basis) are difficult to adapt to the random and intermittent voltage fluctuations in active distribution networks, leading to voltage regulation failure or reverse voltage regulation. Even repeated voltage fluctuations and regulation directions can cause operational problems for the voltage regulating equipment itself. These problems are mainly voltage-related, manifested in two ways: First, the active power injection from distributed energy sources can change the power flow direction, causing an increase in bus voltage and resulting in equipment safety issues; second, the non-full-phase operation of distributed energy sources can lead to three-phase voltage imbalance, causing abnormal overheating of motor equipment. While current bidirectional step-type automatic voltage regulators can determine the system power flow direction, the long operating cycle of mechanical voltage regulators (up to hours) means that if the power flow direction changes during this period, erroneous voltage regulation or even reverse voltage regulation may occur. In recent years, with the development of power electronics technology, solid-state transformers have demonstrated continuous regulation and frequent operation, making them suitable for active distribution networks with large-scale new energy integration. However, due to limitations such as cost and reliability, large-scale application of solid-state transformers is unlikely in the short term. Therefore, ensuring the safe operation of conventional electromagnetic voltage regulators while maximizing the control efficiency of line voltage regulators is crucial for improving the safety and reliability of active distribution networks. Summary of the Invention

[0003] The main objective of this invention is to overcome the shortcomings and deficiencies of the prior art and to propose a control method and system for an active distribution network voltage regulator.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A control method for an active distribution network voltage regulator controller, wherein the voltage regulator is connected between the power supply side and the load side, the input side of the voltage regulator is connected to protective circuit breakers QS1 and QF1, and the output side is connected to isolating switch QS3; a bypass is also provided between the power supply side and the load side, and the bypass is connected to bypass circuit breakers QS2 and QF2; both the input and output sides of the voltage regulator are equipped with surge arresters.

[0006] The control method includes the following steps:

[0007] When the controller starts, it first determines whether the voltage regulator is in normal operation and sets the circuit breaker and tap changer to lockout status.

[0008] Read system parameters and set a timer interrupt;

[0009] The relay protection judgment and status monitoring judgment process includes output overvoltage fault judgment, output undervoltage fault judgment, overcurrent fault judgment, and oil temperature and gas concentration detection.

[0010] Determine whether output overvoltage, undervoltage, or overcurrent fault handling is required. If no output overvoltage occurs, proceed with the voltage regulator up / down control process. If an output overvoltage fault occurs, proceed with output overvoltage fault handling.

[0011] After entering the voltage regulator shift control process, the controller determines the current power flow direction of the line and, based on the power flow direction determination result and the comparison result between the current output voltage and the set voltage, issues an upshift or downshift command to the tap changer.

[0012] Furthermore, the output overvoltage fault determination is specifically as follows:

[0013] Determine whether the controller is in bypass mode and the circuit breaker is not locked. If so, determine whether the voltage regulator output voltage exceeds the set bypass output voltage. If it does, the output overvoltage delay count is incremented, and then it is determined whether the output overvoltage count value exceeds the output overvoltage delay set value. If it does, the overvoltage fault flag is set.

[0014] If the controller is not in bypass mode and the circuit breaker is not locked, then jump to the step of determining whether the output overvoltage count value exceeds the output overvoltage delay setting value.

[0015] If the voltage regulator output voltage does not exceed the set bypass output voltage, the output overvoltage delay count is cleared to zero, and the controller is checked again to see if it is in bypass working mode and the circuit breaker is not locked.

[0016] If the output overvoltage count value does not exceed the output overvoltage delay setting value, then it is determined again whether the controller is in bypass working mode and the circuit breaker is not locked.

[0017] Furthermore, the specific determination of output undervoltage fault is as follows:

[0018] Determine whether the controller is in bypass mode and the circuit breaker is not locked. If so, determine whether the voltage regulator output voltage is lower than the set bypass output voltage. If it is lower, the output undervoltage delay count is incremented, and then it is determined whether the output undervoltage count value exceeds the output undervoltage delay set value. If it exceeds, the undervoltage fault flag is set.

[0019] If the controller is not in bypass mode and the circuit breaker is not locked, the process jumps to the step of determining whether the output undervoltage count value exceeds the output undervoltage delay setting value.

[0020] If the voltage regulator output voltage is not lower than the set bypass output voltage, the output undervoltage delay count is cleared to zero, and the controller is checked again to see if it is in bypass working mode and the circuit breaker is not locked.

[0021] If the output undervoltage count value does not exceed the output undervoltage delay setting value, then it is determined again whether the controller is in bypass working mode and the circuit breaker is not locked.

[0022] Furthermore, the overcurrent fault determination is specifically as follows:

[0023] Determine whether the controller is in bypass mode and the circuit breaker is not locked. If so, determine whether the voltage regulator output current exceeds the set output current. If it does, the output overcurrent delay count is incremented, and then it is determined whether the output overcurrent count value exceeds the output overcurrent delay setting value. If it does, the overcurrent fault flag is set.

[0024] If the controller is not in bypass mode and the circuit breaker is not locked, then jump to the step of determining whether the output overcurrent count value exceeds the output overcurrent delay setting value.

[0025] If the voltage regulator output current does not exceed the set output current, the output overcurrent delay count is cleared to zero, and the controller is checked again to see if it is in bypass mode and the circuit breaker is not locked.

[0026] If the output overcurrent count value does not exceed the output overcurrent delay setting value, then it is determined again whether the controller is in bypass working mode and the circuit breaker is not locked.

[0027] Furthermore, the output overvoltage fault handling specifically includes:

[0028] When the protection circuit breaker QF1 is in the closed position, record the fault data, issue the QF1 command, and check again whether QF1 is in the closed position;

[0029] If the protection circuit breaker QF1 is not in the closed position at this time, it is determined whether the input voltage exceeds the set bypass output voltage. If it does, it is determined whether QF2 is in the closed position. If QF2 is in the closed position, the fault data is recorded and the QF2 command is issued. If QF2 is not in the closed position, the circuit breaker lockout flag is set and the bypass operation mode is entered.

[0030] If the input voltage does not exceed the set bypass output voltage, it is determined whether QF1 and QF2 are both in the open position. If so, the QF2 closing command is issued to make QF2 close, the circuit breaker lockout flag is set, and the bypass operation mode is entered.

[0031] If QF1 and QF2 are not both in the open position, that is, QF2 is in the closed position, then the circuit breaker lockout flag is set and the circuit breaker enters bypass operation mode.

[0032] Furthermore, the specific handling of output undervoltage faults includes:

[0033] When the protection circuit breaker QF1 is in the closed position, record the fault data, issue the QF1 command, and check again whether QF1 is in the closed position;

[0034] If the protection circuit breaker QF1 is not in the closed position at this time, it is determined whether the input voltage is lower than the set bypass output voltage. If it is lower, it is determined whether QF2 is in the closed position. If QF2 is in the closed position, the fault data is recorded and the QF2 command is issued. If QF2 is not in the closed position, the circuit breaker lockout flag is set and the bypass operation mode is entered.

[0035] If the input voltage is not lower than the set bypass output voltage, it is determined whether QF1 and QF2 are both in the open position. If so, the QF2 closing command is issued to make QF2 close, the circuit breaker lockout flag is set, and the bypass operation mode is entered.

[0036] If QF1 and QF2 are not both in the open position, that is, QF2 is in the closed position, then the circuit breaker lockout flag is set and the circuit breaker enters bypass operation mode.

[0037] Furthermore, overcurrent fault handling specifically includes:

[0038] When the protection circuit breaker QF1 is in the closed position, record the fault data, issue the QF1 command, and check again whether QF1 is in the closed position;

[0039] If the protection circuit breaker QF1 is not in the closed position, determine whether the output current exceeds the set voltage regulator output current. If it does, determine whether QF2 is in the closed position. If QF2 is in the closed position, record the fault data and issue the QF2 command. If QF2 is not in the closed position, set the circuit breaker lockout flag and enter the bypass operation mode.

[0040] If the output current does not exceed the set voltage regulator output current, it is determined whether QF1 and QF2 are both in the open position. If so, the QF2 closing command is issued to make QF2 in the closed position, the circuit breaker lockout flag is set, and the bypass operation mode is entered.

[0041] If QF1 and QF2 are not both in the open position, that is, QF2 is in the closed position, then the circuit breaker lockout flag is set and the circuit breaker enters bypass operation mode.

[0042] Furthermore, the specific process of the voltage regulator's shifting control is as follows:

[0043] First, determine whether the tap changer is locked. If it is not locked, determine the power flow direction. If the power flow direction is positive, the reference voltage is the positive reference voltage; if the power flow direction is negative, the reference voltage is the negative reference voltage.

[0044] Determine if the output voltage simultaneously meets the conditions of being greater than the low-voltage blocking voltage, less than the reference voltage, and having a difference of more than 25kV from the reference voltage. If so, increment the upshift delay counter, determine if the upshift delay time has been reached, and if so, the controller sends an upshift command, sets the tap changer action delay, sets the tap changer lockout flag, changes the gear position, clears the tap changer action delay and lockout flag, returns to the step of determining whether the tap changer is locked, and performs the upshift / downshift logic determination again.

[0045] If the shift delay time has not been reached, return to the step of determining whether the tap changer is locked.

[0046] If the gear position does not change, determine whether the tap changer action delay time has been reached. If yes, clear the tap changer action delay time and set the tap changer lockout flag, then return to the step of determining whether the tap changer is locked. If no, return to the step of determining the gear position change.

[0047] If the output voltage is less than the reference voltage and the difference between the two voltages is less than 25kV, the upshift delay count decreases. The system then checks if the input voltage is greater than the reference voltage and the difference between the two voltages is greater than 25kV, but less than the allowable voltage range. If yes, the downshift delay count decreases, and the system returns to the step of determining if the tap changer is locked. If no, the downshift delay count increases, and the system checks if the downshift delay time has been reached. If it has, the controller sends a downshift command and sets the tap changer action delay and lockout flags. If it has not been reached, the system returns to the step of determining if the tap changer is locked.

[0048] Furthermore, when the voltage regulator is operating in a network with a large number of distributed energy sources or a ring network, the system power flow is reassessed during the voltage regulation operation, including:

[0049] During the voltage regulation operation of the voltage regulator, the system power flow is reassessed as follows:

[0050] During the voltage regulator's upshifting process, after the upshifting delay time is reached, a reverse power flow judgment is performed. If the reverse is true, a downshifting command is issued, and the tap changer action delay and lockout flag are set.

[0051] If not, issue an upshift command, set the tap changer action delay and lockout flag;

[0052] During the voltage regulation operation of the voltage regulator, the system power flow is reassessed as follows:

[0053] During the downshifting process of the voltage regulator, after the downshifting delay time is reached, a reverse power flow judgment is performed. If it is, an upshifting command is issued, and the tap changer action delay and lockout flag are set.

[0054] If not, issue a downshift command, set the tap changer action delay and lockout flag.

[0055] The present invention also includes a control system for an active distribution network voltage regulator controller, the system employing the control method provided by the present invention, including a relay protection module and a voltage regulator up / down control module;

[0056] The relay protection module includes a line overvoltage and undervoltage judgment module and a status monitoring module. It is executed before the voltage regulator is put into operation to determine whether the current line voltage status is within the voltage regulation range allowed by the line voltage regulator and to detect the current operating status of the voltage regulating transformer.

[0057] The status monitoring module is used to monitor and determine the operating status of the pressure regulator based on whether the oil temperature and gas concentration exceed the standard.

[0058] The voltage regulator shift control module is used for the initial judgment of the power flow and the secondary judgment of the power flow direction before each voltage regulation action, to prevent the mechanical structure from changing the power flow direction during continuous operation, which could cause incorrect voltage regulation or reverse voltage regulation.

[0059] The regulator's shift control module also includes a delay counting module for precise control of the pressure setting.

[0060] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0061] 1. This invention realizes a centralized integrated design for relay protection, operation status detection and voltage regulation commands of voltage regulating transformers, avoiding too many complex control units.

[0062] 2. This invention enables the judgment of overvoltage, undervoltage, and overcurrent in the line operation status, preventing damage to the voltage regulator caused by erroneous connection of the voltage regulator to the line.

[0063] 3. The present invention performs power flow direction judgment before each step voltage adjustment operation, avoiding the risk of false voltage adjustment and reverse voltage adjustment caused by the lag of the mechanical voltage adjustment system. Attached Figure Description

[0064] Figure 1 This is the overall flowchart of the method of the present invention;

[0065] Figure 2 This is a schematic diagram of the voltage regulator connected to the system in this embodiment;

[0066] Figure 3 This is a flowchart of the overvoltage fault detection and judgment process of the present invention;

[0067] Figure 4 This is a flowchart of the output undervoltage fault detection and determination process of the present invention;

[0068] Figure 5 This is a flowchart of the overcurrent fault detection and judgment process of the present invention;

[0069] Figure 6 This is a flowchart of the overvoltage fault handling process of the present invention;

[0070] Figure 7 This is a flowchart of the output undervoltage fault handling process of the present invention;

[0071] Figure 8 This is a flowchart of the overcurrent fault handling process of the present invention;

[0072] Figure 9 This is a flowchart of the voltage regulator shifting control process of the present invention;

[0073] Figure 10 This is a flowchart of the voltage regulator shifting control process in the ring network working mode of the present invention. Detailed Implementation

[0074] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0075] Example

[0076] This invention provides a control method for an active distribution network voltage regulator controller, such as... Figure 2 As shown, the voltage regulator is connected between the power supply side and the load side. The input side of the voltage regulator is connected to protective circuit breakers (with isolating switches) QS1 and QF1, and the output side is connected to isolating switch QS3. A bypass is also provided between the power supply side and the load side, with bypass circuit breakers (with isolating switches) QS2 and QF2 on the bypass. The input and output sides of the voltage regulator are respectively equipped with surge arresters F1 and F2.

[0077] like Figure 1 As shown, the control method includes the following steps:

[0078] When the controller starts, it first determines whether the voltage regulator is in normal operation and sets the circuit breaker and tap changer to lockout status.

[0079] Read system parameters and set a timer interrupt;

[0080] The relay protection judgment and status monitoring judgment process includes output overvoltage fault judgment, output undervoltage fault judgment, overcurrent fault judgment, and oil temperature and gas concentration detection.

[0081] Determine whether output overvoltage, undervoltage, or overcurrent fault handling is required. If no overvoltage occurs, proceed with the voltage regulator up / down control process. If an overvoltage fault occurs, proceed with output overvoltage fault handling.

[0082] After entering the tap changer shifting process, the controller determines the current power flow direction of the line and, based on the power flow direction determination result and the comparison between the current output voltage and the set voltage, issues an up or down command to the tap changer.

[0083] In this embodiment, the overvoltage fault determination process is as follows: Figure 3 As shown, the output overvoltage fault handling process is as follows: Figure 6 As shown.

[0084] In this embodiment, the output undervoltage fault determination process is as follows: Figure 4 As shown, the output undervoltage fault handling process is as follows: Figure 7 As shown.

[0085] In this embodiment, the overcurrent fault determination process is as follows: Figure 5 As shown, the overcurrent fault handling process is as follows: Figure 8 As shown.

[0086] The specific process of the voltage regulator's shift control is as follows:

[0087] First, determine whether the tap changer is locked. If it is not locked, determine the power flow direction. If the power flow direction is positive, the reference voltage is the positive reference voltage; if the power flow direction is negative, the reference voltage is the negative reference voltage.

[0088] Determine if the output voltage simultaneously meets the conditions of being greater than the low-voltage blocking voltage, less than the reference voltage, and having a difference of more than 25kV from the reference voltage. If so, increment the upshift delay counter, determine if the upshift delay time has been reached, and if so, the controller sends an upshift command, sets the tap changer action delay, sets the tap changer lockout flag, changes the gear position, clears the tap changer action delay and lockout flag, returns to the step of determining whether the tap changer is locked, and performs the upshift / downshift logic determination again.

[0089] If the shift delay time has not been reached, return to the step of determining whether the tap changer is locked.

[0090] If the gear position does not change, determine whether the tap changer action delay time has been reached. If yes, clear the tap changer action delay time and set the tap changer lockout flag, then return to the step of determining whether the tap changer is locked. If no, return to the step of determining the gear position change.

[0091] If the output voltage is less than the reference voltage and the difference between the two voltages is less than 25kV, the upshift delay count decreases. The system then checks if the input voltage is greater than the reference voltage and the difference between the two voltages is greater than 25kV, but less than the allowable range of the reference voltage. If yes, the downshift delay count decreases, and the system returns to the step of determining if the tap changer is locked. If no, the downshift delay count increases, and the system checks if the downshift delay time has been reached. If it has, the controller sends a downshift command and sets the tap changer action delay and lockout flags. If it has not been reached, the system returns to the step of determining if the tap changer is locked.

[0092] In this embodiment, the voltage regulator's shift control process is as follows: Figure 9 As shown.

[0093] When the voltage regulator operates in a complex power grid with extensive distributed energy integration or ring networks, the power flow direction changes rapidly. Therefore, during the voltage regulation operation, the system power flow is reassessed to effectively avoid the lag in the continuous mechanical voltage regulation process of the voltage regulating transformer and prevent erroneous voltage regulation and reverse voltage regulation. In this embodiment, as shown... Figure 10 As shown, specifically:

[0094] During the voltage regulator's upshifting process, after the upshifting delay time is reached, a reverse power flow judgment is performed. If the reverse is true, a downshifting command is issued, and the tap changer action delay and lockout flag are set.

[0095] If not, issue an upshift command, set the tap changer action delay and lockout flag.

[0096] During the voltage regulation operation of the voltage regulator, the system power flow is reassessed as follows:

[0097] During the downshifting process of the voltage regulator, after the downshifting delay time is reached, a reverse power flow judgment is performed. If it is, an upshifting command is issued, and the tap changer action delay and lockout flag are set.

[0098] If not, issue a downshift command, set the tap changer action delay and lockout flag.

[0099] In another embodiment, a control system for an active distribution network voltage regulator controller is also provided. The system adopts the control method of the above embodiment and includes a relay protection module and a voltage regulator shift control module.

[0100] The relay protection module includes a line overvoltage and undervoltage judgment module and a status monitoring module. It operates before the voltage regulator is put into operation and is used to determine whether the current line voltage status is within the voltage regulation range allowed by the line voltage regulator and to detect the current operating status of the voltage regulating transformer.

[0101] The status monitoring module is used to monitor and determine the operating status of the pressure regulator based on whether the oil temperature and gas concentration exceed the standard.

[0102] The voltage regulator shift control module is used for the initial judgment of the power flow and the secondary judgment of the power flow direction before each voltage regulation action, to prevent the mechanical structure from changing the power flow direction during continuous operation, which could cause incorrect voltage regulation or reverse voltage regulation.

[0103] The regulator's shift control module also includes a delay counting module for precise control of the pressure setting.

[0104] It should also be noted that, in this specification, terms such as "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0105] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for an active distribution network voltage regulator controller, characterized in that, The voltage regulator is connected between the power supply side and the load side. The input side of the voltage regulator is connected to the protection circuit breakers QS1 and QF1, and the output side is connected to the isolating switch QS3. A bypass is also provided between the power supply side and the load side, and there are bypass circuit breakers QS2 and QF2 on the bypass. There are surge arresters on both the input and output sides of the voltage regulator. The control method includes the following steps: When the controller starts, it first determines whether the voltage regulator is in normal operation and sets the circuit breaker and tap changer to lockout status. Read system parameters and set a timer interrupt; The relay protection judgment and condition monitoring judgment process includes output overvoltage fault judgment, output undervoltage fault judgment, overcurrent fault judgment, and oil temperature and gas concentration detection; the output overvoltage fault judgment is specifically as follows: Determine whether the controller is in bypass mode and the circuit breaker is not locked. If so, determine whether the voltage regulator output voltage exceeds the set bypass output voltage. If it does, the output overvoltage delay count is incremented, and then it is determined whether the output overvoltage count value exceeds the output overvoltage delay set value. If it does, the overvoltage fault flag is set. If the controller is not in bypass mode and the circuit breaker is not locked, then jump to the step of determining whether the output overvoltage count value exceeds the output overvoltage delay setting value. If the voltage regulator output voltage does not exceed the set bypass output voltage, the output overvoltage delay count is cleared to zero, and the controller is checked again to see if it is in bypass working mode and the circuit breaker is not locked. If the output overvoltage count value does not exceed the output overvoltage delay setting value, then check again whether the controller is in bypass working mode and the circuit breaker is not locked. Determine whether output overvoltage, undervoltage, or overcurrent fault handling is required. If no output overvoltage occurs, proceed with the voltage regulator up / down control process. If an output overvoltage fault occurs, proceed with output overvoltage fault handling. After entering the voltage regulator shift control process, the controller determines the current power flow direction of the line and, based on the power flow direction determination result and the comparison result between the current output voltage and the set voltage, issues an upshift or downshift command to the tap changer.

2. The control method for the active distribution network voltage regulator controller according to claim 1, characterized in that, The specific steps for determining output undervoltage faults are as follows: Determine whether the controller is in bypass mode and the circuit breaker is not locked. If so, determine whether the voltage regulator output voltage is lower than the set bypass output voltage. If it is lower, the output undervoltage delay count is incremented, and then it is determined whether the output undervoltage count value exceeds the output undervoltage delay set value. If it exceeds, the undervoltage fault flag is set. If the controller is not in bypass mode and the circuit breaker is not locked, the process jumps to the step of determining whether the output undervoltage count value exceeds the output undervoltage delay setting value. If the voltage regulator output voltage is not lower than the set bypass output voltage, the output undervoltage delay count is cleared to zero, and the controller is checked again to see if it is in bypass working mode and the circuit breaker is not locked. If the output undervoltage count value does not exceed the output undervoltage delay setting value, then it is determined again whether the controller is in bypass working mode and the circuit breaker is not locked.

3. The control method for the active distribution network voltage regulator controller according to claim 1, characterized in that, The overcurrent fault determination is as follows: Determine whether the controller is in bypass mode and the circuit breaker is not locked. If so, determine whether the voltage regulator output current exceeds the set output current. If it does, the output overcurrent delay count is incremented, and then it is determined whether the output overcurrent count value exceeds the output overcurrent delay setting value. If it does, the overcurrent fault flag is set. If the controller is not in bypass mode and the circuit breaker is not locked, then jump to the step of determining whether the output overcurrent count value exceeds the output overcurrent delay setting value. If the voltage regulator output current does not exceed the set output current, the output overcurrent delay count is cleared to zero, and the controller is checked again to see if it is in bypass mode and the circuit breaker is not locked. If the output overcurrent count value does not exceed the output overcurrent delay setting value, then it is determined again whether the controller is in bypass working mode and the circuit breaker is not locked.

4. The control method for the active distribution network voltage regulator controller according to claim 1, characterized in that, Output overvoltage fault handling specifically includes: When the protection circuit breaker QF1 is in the closed position, record the fault data, issue the QF1 command, and check again whether QF1 is in the closed position; If the protection circuit breaker QF1 is not in the closed position at this time, it is determined whether the input voltage exceeds the set bypass output voltage. If it does, it is determined whether QF2 is in the closed position. If QF2 is in the closed position, the fault data is recorded and the QF2 command is issued. If QF2 is not in the closed position, the circuit breaker lockout flag is set and the bypass operation mode is entered. If the input voltage does not exceed the set bypass output voltage, it is determined whether QF1 and QF2 are both in the open position. If so, the QF2 closing command is issued to make QF2 close, the circuit breaker lockout flag is set, and the bypass operation mode is entered. If QF1 and QF2 are not both in the open position, that is, QF2 is in the closed position, then the circuit breaker lockout flag is set and the circuit breaker enters bypass operation mode.

5. The control method for the active distribution network voltage regulator controller according to claim 2, characterized in that, Output undervoltage fault handling specifically includes: When the protection circuit breaker QF1 is in the closed position, record the fault data, issue the QF1 command, and check again whether QF1 is in the closed position; If the protection circuit breaker QF1 is not in the closed position at this time, it is determined whether the input voltage is lower than the set bypass output voltage. If it is lower, it is determined whether QF2 is in the closed position. If QF2 is in the closed position, the fault data is recorded and the QF2 command is issued. If QF2 is not in the closed position, the circuit breaker lockout flag is set and the bypass operation mode is entered. If the input voltage is not lower than the set bypass output voltage, it is determined whether QF1 and QF2 are both in the open position. If so, the QF2 closing command is issued to make QF2 close, the circuit breaker lockout flag is set, and the bypass operation mode is entered. If QF1 and QF2 are not both in the open position, that is, QF2 is in the closed position, then the circuit breaker lockout flag is set and the circuit breaker enters bypass operation mode.

6. The control method for the active distribution network voltage regulator controller according to claim 3, characterized in that, Overcurrent fault handling specifically includes: When the protection circuit breaker QF1 is in the closed position, record the fault data, issue the QF1 command, and check again whether QF1 is in the closed position; If the protection circuit breaker QF1 is not in the closed position, determine whether the output current exceeds the set voltage regulator output current. If it does, determine whether QF2 is in the closed position. If QF2 is in the closed position, record the fault data and issue the QF2 command. If QF2 is not in the closed position, set the circuit breaker lockout flag and enter the bypass operation mode. If the output current does not exceed the set voltage regulator output current, it is determined whether QF1 and QF2 are both in the open position. If so, the QF2 closing command is issued to make QF2 in the closed position, the circuit breaker lockout flag is set, and the bypass operation mode is entered. If QF1 and QF2 are not both in the open position, that is, QF2 is in the closed position, then the circuit breaker lockout flag is set and the circuit breaker enters bypass operation mode.

7. The control method for the active distribution network voltage regulator controller according to claim 1, characterized in that, The specific process of the voltage regulator's shift control is as follows: First, determine whether the tap changer is locked. If it is not locked, determine the power flow direction. If the power flow direction is positive, the reference voltage is the positive reference voltage; if the power flow direction is negative, the reference voltage is the negative reference voltage. Determine if the output voltage simultaneously meets the conditions of being greater than the low-voltage blocking voltage, less than the reference voltage, and having a difference of more than 25kV from the reference voltage. If so, increment the upshift delay counter, determine if the upshift delay time has been reached, and if so, the controller sends an upshift command, sets the tap changer action delay, sets the tap changer lockout flag, changes the gear position, clears the tap changer action delay and lockout flag, returns to the step of determining whether the tap changer is locked, and performs the upshift / downshift logic determination again. If the shift delay time has not been reached, return to the step of determining whether the tap changer is locked. If the gear position does not change, determine whether the tap changer action delay time has been reached. If yes, clear the tap changer action delay time and set the tap changer lockout flag, then return to the step of determining whether the tap changer is locked. If no, return to the step of determining the gear position change. If the output voltage is less than the reference voltage and the difference between the two voltages is less than 25kV, the upshift delay count decreases. The system then checks if the input voltage is greater than the reference voltage and the difference between the two voltages is greater than 25kV, but less than the allowable voltage range. If yes, the downshift delay count decreases, and the system returns to the step of determining if the tap changer is locked. If no, the downshift delay count increases, and the system checks if the downshift delay time has been reached. If it has, the controller sends a downshift command and sets the tap changer action delay and lockout flags. If it has not been reached, the system returns to the step of determining if the tap changer is locked.

8. The control method for the active distribution network voltage regulator controller according to claim 7, characterized in that, When the voltage regulator is operating in a network with a large number of distributed energy sources or a ring network, the system power flow should be reassessed during the voltage regulation operation, including: During the voltage regulation operation of the voltage regulator, the system power flow is reassessed as follows: During the voltage regulator's upshifting process, after the upshifting delay time is reached, a reverse power flow judgment is performed. If the reverse is true, a downshifting command is issued, and the tap changer action delay and lockout flag are set. If not, issue an upshift command, set the tap changer action delay and lockout flag; During the voltage regulation operation of the voltage regulator, the system power flow is reassessed as follows: During the downshifting process of the voltage regulator, after the downshifting delay time is reached, a reverse power flow judgment is performed. If it is, an upshifting command is issued, and the tap changer action delay and lockout flag are set. If not, issue a downshift command, set the tap changer action delay and lockout flag.

9. A control system for an active distribution network voltage regulator controller, characterized in that, The system employs the method described in any one of claims 1-8, comprising a relay protection module and a voltage regulator shift control module; The relay protection module includes a line overvoltage and undervoltage judgment module and a status monitoring module. It is executed before the voltage regulator is put into operation to determine whether the current line voltage status is within the voltage regulation range allowed by the line voltage regulator and to detect the current operating status of the voltage regulating transformer. The status monitoring module is used to monitor and determine the operating status of the pressure regulator based on whether the oil temperature and gas concentration exceed the standard. The voltage regulator shift control module is used for the initial judgment of the power flow and the secondary judgment of the power flow direction before each voltage regulation action, to prevent the mechanical structure from changing the power flow direction during continuous operation, which could cause incorrect voltage regulation or reverse voltage regulation. The regulator's shift control module also includes a delay counting module for precise control of the pressure setting.

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