A transformer area power regulation method, system and device based on intelligent internet of things table

Abstract

The present application relates to the technical field of power management, and is a kind of based on intelligent internet of things table's transformer area power regulation method, system and device.The transformer area power regulation method comprises the following steps: S1: collecting the characteristic data of photovoltaic inverter;S2: collecting the power data of transformer area, judging whether the electric energy index of transformer area is out of limit: yes, then S3;S3: judging whether to execute three times regulation in preset period: yes, then S4, otherwise, generating regulation strategy, S5;S4: analyzing fault, and doing emergency treatment to internet of things table or inverter;S5: regulating inverter according to regulation strategy, and feeding back regulation result to master station server.The present application regulates all photovoltaic inverters through intelligent internet of things table when the electric energy index of transformer area is out of limit, so as to make the electric energy index of transformer area return to the threshold range set, and solve the hidden danger of photovoltaic user unordered on-line to transformer area power safe operation.

Description

Technical Field

[0001] This invention relates to the field of power management technology, and in particular to a method for regulating power distribution areas based on smart meters, a system for regulating power distribution areas based on smart meters, and a device for regulating power distribution areas based on smart meters. Background Technology

[0002] With the national strategy of building a new power system based on new energy sources and achieving "carbon peaking and carbon neutrality," the construction of this new power system is accelerating, and the development of new energy sources will usher in new opportunities. The installation of photovoltaic (PV) systems for low-voltage 400V residential users is bound to experience explosive growth. The rapid development of low-voltage distributed PV grid connections is changing the traditional unidirectional power flow pattern of distribution networks.

[0003] In the construction of low-voltage 400V distribution areas, more low-voltage distributed photovoltaic (PV) users are adopting direct grid connection. However, PV users' grid connection exhibits a time-sensitive and seasonal trend, coupled with insufficient local absorption capacity, leading to excessive grid-connected power causing line voltage rises or even exceeding limits, posing a threat to the safe operation of the distribution network. The current level of intelligence and construction speed of the distribution network can no longer meet the needs of the rapid development of new energy sources, necessitating an improvement in the operation and control capabilities of distributed PV at the distribution area level. Summary of the Invention

[0004] Therefore, it is necessary to provide a power control method, system, and device for low-voltage distribution areas based on smart meters to address the problem that it is difficult to control the overall operation of photovoltaic inverters in existing low-voltage distribution areas, which leads to disordered grid connection of photovoltaic inverters and thus poses a safety hazard to the power operation of the distribution area.

[0005] This invention is achieved through the following technical solution: A method for regulating power distribution in a transformer substation based on a smart IoT meter includes the following steps:

[0006] S1: The smart IoT meter collects characteristic data from the photovoltaic inverter according to a preset cycle and transmits the characteristic data to the main station server. The characteristic data includes the output voltage and output current of the photovoltaic inverter.

[0007] S2: The main station server collects power data for the transformer area through measuring devices. Based on the power data, it calculates the current power index for the transformer area and determines whether the power index exceeds a preset threshold. If yes, proceed to S3. Otherwise, return to S1. The power data includes: total three-phase voltage, total three-phase current, voltage and current of each phase. The power index includes the total power of the transformer area and the three-phase imbalance.

[0008] S3: Determine whether the smart IoT meter has performed three photovoltaic inverter controls within a time period, and make the following decision:

[0009] (i) If so, the smart IoT meter generates a fault signal and sends the fault signal to the main station server to perform S4.

[0010] (ii) Otherwise, the main station server generates a corresponding control strategy based on the feature data and power data, and transmits the control strategy to the corresponding smart IoT meter for S5.

[0011] The method for generating the control strategy is as follows:

[0012] S31: Calculate the total power and the over-limit ratio of the three-phase unbalance in the current transformer area based on the total three-phase voltage, total three-phase current, partial voltage of each phase, and partial current of each phase.

[0013] S32: Calculate the control coefficient of the photovoltaic inverter connected to each phase line based on the over-limit ratio and the output voltage and output current of each photovoltaic inverter. The control coefficient is the ratio of the output power of the photovoltaic inverter after control to the output power before control.

[0014] S33: Set the control strategy for each photovoltaic inverter based on the control coefficient and the characteristic information of each photovoltaic inverter.

[0015] S4: The master server receives and analyzes the fault signal and makes the following decision:

[0016] (i) If a smart IoT meter malfunctions, a nearby smart IoT meter will be used to perform the control, and the process will return to S2. Record the logical addresses of all malfunctioning smart IoT meters and send a maintenance request.

[0017] (ii) If multiple photovoltaic inverters are faulty, suspend the grid connection of all faulty photovoltaic inverters and return to S2. Record the logical addresses of all faulty photovoltaic inverters and send a maintenance request.

[0018] S5: After receiving the control strategy, the smart IoT meter adjusts the operating status of each photovoltaic inverter according to the control strategy. Return to S1.

[0019] This invention collects characteristic data from photovoltaic (PV) inverters using smart IoT meters. When the power consumption index of a distribution area exceeds the limit, it formulates corresponding control strategies based on the control methods supported by each PV inverter, the current power data of the distribution area, and the characteristic data of the PV inverters. Then, the smart IoT meters perform overall control of all PV inverters to restore the power consumption index of the distribution area to the set threshold range, thus resolving the potential safety risks to the power supply operation of the distribution area caused by disorderly grid connection by PV users. Furthermore, through precise communication between the main station server, smart IoT meters, and PV inverters, faults in smart IoT meters or PV inverters can be detected promptly, and emergency strategies can be implemented to maintain the accuracy of power monitoring or control of PV inverters, thereby avoiding property losses for PV users or power companies.

[0020] In one embodiment, the smart meter and the photovoltaic inverter verify each other through profile information, thereby enabling precise data interaction between the smart meter and the photovoltaic inverter. The profile information is established by the main server.

[0021] The profile information includes the photovoltaic inverter's coding information and characteristic information. The coding information is automatically generated according to the order in which each photovoltaic inverter's profile is created, and each coding information is unique. The characteristic information includes the control methods supported by the photovoltaic inverter. Control methods include one or more of active power regulation, reactive power regulation, and power factor regulation.

[0022] In one embodiment, the total power P of the transformer area is calculated as follows:

[0023]

[0024] Where U is the total three-phase voltage and I is the total three-phase current. The power factor.

[0025] In one embodiment, the method for calculating the three-phase imbalance of the transformer area is as follows:

[0026]

[0027] in, For three-phase imbalance, For I A I B and I C The maximum value in, For I A I B and I C The minimum value in, I A I B and I C These are the currents for phases A, B, and C of the transformer substation, respectively.

[0028] In one embodiment, the over-limit ratio is calculated as follows:

[0029]

[0030] in, This represents the percentage of the total power output of the transformer substation that exceeds the limit. The percentage exceeding the limit for three-phase imbalance in the transformer substation. Power threshold This is the threshold for three-phase imbalance.

[0031] In one embodiment, the general method for calculating the control coefficient is as follows:

[0032]

[0033] in, These are the total currents of the photovoltaic inverters for phases A, B, and C, respectively.

[0034] In one embodiment, when the photovoltaic inverters of each phase are controlled separately, the calculation formulas for the control coefficients K1, K2, and K3 of the photovoltaic inverters on each phase are as follows:

[0035] when At that time, the formula for calculating the control coefficient is as follows:

[0036]

[0037] when At that time, the formula for calculating the control coefficient is as follows:

[0038]

[0039] Wherein, K1, K2, and K3 are the control coefficients for phase A, phase B, and phase C, respectively. This represents the average current of phases A, B, and C.

[0040] when At that time, the formula for calculating the control coefficient is as follows:

[0041]

[0042] in, These are the total voltages of the photovoltaic inverters for phases A, B, and C, respectively.

[0043] In one embodiment, the method for generating the control strategy for each photovoltaic inverter is as follows:

[0044] S331: The master server sets the priority of the control mode for each photovoltaic inverter. The priority indicates the order in which the photovoltaic inverters preferentially adopt the control mode.

[0045] S332: Generate a control strategy for each photovoltaic inverter based on the control coefficient of each phase, the phase lines connected to each photovoltaic inverter, and the priority.

[0046] The present invention also provides a power control system for distribution transformers based on smart IoT meters. The power control system for distribution transformers includes: a data acquisition module, a computing module, a decision-making module, a coding module, and a photovoltaic inverter control module.

[0047] The data acquisition module is used for: (1) acquiring characteristic data of photovoltaic inverters; and (2) acquiring power data of distribution areas.

[0048] The calculation module is used for: (1) calculating power indicators based on power data. Power indicators include the total power of the transformer area and the three-phase imbalance. (2) calculating the control coefficient of each photovoltaic inverter based on the current power indicators, the preset power indicator thresholds, and the characteristic data of the photovoltaic inverter.

[0049] The decision module is used to: (1) determine whether the current power index exceeds the preset threshold. If it does not exceed the threshold, the current operating state of the photovoltaic inverter is maintained. If it exceeds the threshold, an over-limit signal is output. (2) when the power index exceeds the preset threshold, determine whether the smart IoT meter has performed photovoltaic inverter regulation three times within a time period. If it has performed three times, a fault signal is output. If it has not performed three times, a regulation signal is output. (3) after outputting the fault signal, determine the cause of the fault based on the change in the photovoltaic inverter. If there is a smart IoT meter fault, a smart IoT meter fault signal is output. If there are multiple photovoltaic inverter faults, a photovoltaic inverter fault signal is output.

[0050] The encoding module is used to encode the smart IoT meter and the photovoltaic inverter respectively, so as to achieve accurate communication between the smart IoT meter and the photovoltaic inverter.

[0051] The photovoltaic inverter control module is used to adjust the output power of each photovoltaic inverter according to the control coefficient of each photovoltaic inverter.

[0052] The present invention also provides a power control device for transformer substations based on smart IoT meters. The power control device for transformer substations includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor.

[0053] Each functional module in the distribution area power control device based on smart IoT meters is deployed in the manner described above for the distribution area power control system. When the processor executes the computer program, it implements the steps of the distribution area power control method based on smart IoT meters as described above, thereby enabling precise control of the photovoltaic inverter when the power index of the distribution area exceeds the limit.

[0054] Compared with the prior art, the present invention has the following beneficial effects:

[0055] 1. This invention collects characteristic data from photovoltaic (PV) inverters using smart IoT meters. When the power consumption index of a distribution area exceeds the limit, it formulates corresponding control strategies based on the control methods supported by each PV inverter, the current power data of the distribution area, and the characteristic data of the PV inverters. Then, the smart IoT meters perform overall control of all PV inverters to restore the power consumption index of the distribution area to the set threshold range, thus resolving the potential safety risks to the power supply operation of the distribution area caused by disorderly grid connection by PV users. Furthermore, through precise communication between the main station server, smart IoT meters, and PV inverters, faults in smart IoT meters or PV inverters can be detected promptly, and emergency strategies can be implemented to maintain the accuracy of power monitoring or control of PV inverters, thereby avoiding property losses for PV users or power companies. Attached Figure Description

[0056] Figure 1 This is a flowchart of the power control method for transformer substations based on smart IoT meters according to Embodiment 1 of the present invention;

[0057] Figure 2 for Figure 1 A flowchart of emergency handling methods when a smart IoT meter or inverter malfunctions;

[0058] Figure 3 To adopt Figure 1 A schematic diagram of the structure of a distribution area power control system based on smart IoT meters. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] It should be noted that when a component is said to be "installed on" another component, it can be directly on the other component or it may be in a component that is centered on it. When a component is said to be "set on" another component, it can be directly set on the other component or it may also be in a component that is centered on it. When a component is said to be "fixed to" another component, it can be directly fixed to the other component or it may also be in a component that is centered on it.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0062] Example 1

[0063] Please see Figure 1 This is a flowchart of the power regulation method for transformer substations based on smart meters according to Embodiment 1 of the present invention. The power regulation method for transformer substations based on smart meters includes the following steps:

[0064] S1: The smart IoT meter collects characteristic data from the photovoltaic inverter according to a preset cycle and transmits the characteristic data to the main station server. The characteristic data includes the output voltage and output current of the photovoltaic inverter. The photovoltaic inverter contains one or more registers. The function of the register is to store binary code; it is composed of flip-flops with storage functions. One flip-flop can store 1 bit of binary code, so a register storing n bits of binary code requires n flip-flops. Each register in the photovoltaic inverter is used to store different characteristic information of the photovoltaic inverter, such as the output voltage, output current, output power, input voltage, input current, and input power. In this embodiment, only the grid-connected power of the photovoltaic inverter is controlled; therefore, only the output current and output voltage of the photovoltaic inverter need to be collected.

[0065] The smart IoT meter and the photovoltaic inverter verify each other through profile information, thereby enabling precise data exchange between them. The profile information is established by the main server.

[0066] The profile information includes the photovoltaic (PV) inverter's coding information and characteristic information. The coding information is automatically generated by the master server according to the order in which each PV inverter's profile is created, and each coding information is unique. The coding information includes not only the coding information representing the PV inverter's logical address but also the coding information representing the corresponding smart meter. The characteristic information includes the control methods supported by the PV inverter. Control methods include one or more of active power regulation, reactive power regulation, and power factor regulation. When the master server regulates the PV inverter's output power through the smart meter, the master server generates a corresponding control strategy based on the applicable control method for each PV inverter. The profile information also includes the communication protocol between the PV inverter and the smart meter. The smart meter interacts with the PV inverter through a successfully matched communication protocol. The specific method for the smart meter to collect the characteristic data of the PV inverter is as follows:

[0067] The master server distributes the archive information. The smart IoT meter receives and parses the archive information, communicates with the corresponding photovoltaic inverter according to the communication protocol in the archive information, and sends the requested read data from the parsed archive information to the corresponding photovoltaic inverter. After receiving the read data, the photovoltaic inverter generates read response data based on its internal register data, and then sends the read response data to the smart IoT meter. The smart IoT meter forwards the read response data to the master server. The master server parses the read response data, thereby obtaining the characteristic data of the photovoltaic inverter.

[0068] S2: The main station server collects power data for the transformer area through a measuring device. Based on the power data, it calculates the current power index for the transformer area and determines whether the power index exceeds a preset threshold. If yes, proceed to S3; otherwise, return to S1. The power data includes: total three-phase voltage, total three-phase current, voltage and current of each phase. The power index includes the total power of the transformer area and the three-phase imbalance.

[0069] Measuring devices can include current transformers, voltage transformers, voltmeters, ammeters, multimeters, and detection elements. During grid connection, the disorderly operation of photovoltaic (PV) inverters by PV users—that is, the intermittent and quantitative power delivery by PV inverters connected to each phase—makes it difficult to control the total power and three-phase imbalance of the distribution area, posing a significant threat to the safe operation of the area. Setting thresholds based on the total capacity of the distribution area, including total power thresholds and three-phase imbalance thresholds, is necessary to control the grid connection power of PV inverters and maintain the safe operation of the distribution area.

[0070] The calculation method for the total power P of the transformer area is as follows:

[0071]

[0072] Where U is the total three-phase voltage and I is the total three-phase current. The power factor is the ratio of active power to apparent power in an AC circuit.

[0073] Where P is the active power, i.e. the total power of the transformer area, and S is the apparent power.

[0074] According to P 2 =Q 2 +S 2 Therefore, the average power factor is:

[0075]

[0076] Among them, W P W represents active power. Q This refers to reactive power.

[0077] The calculation method for the three-phase unbalance of the transformer substation is as follows:

[0078]

[0079] in, For three-phase imbalance, For I A I B and I C The maximum value in, For I A I B and I C The minimum value in, I A I B and I C These are the currents for phases A, B, and C of the transformer substation, respectively.

[0080] S3: Determine whether the smart IoT meter has performed three photovoltaic inverter controls within a time period, and make the following decision:

[0081] (i) If so, a fault signal is sent to the main station server to initiate S4. Generally, after one adjustment of the photovoltaic inverter, if the number of newly added or temporarily disconnected photovoltaic inverters is small and has no significant impact on the overall power index of the distribution area, a single adjustment is sufficient to restore the power index to the normal range. If the adjustment objective is not achieved after three adjustments, it can be assumed that the smart meter or photovoltaic inverter has malfunctioned, resulting in some adjustments not being implemented. Therefore, an error report needs to be sent to the main station server for emergency handling.

[0082] (ii) Otherwise, a corresponding control strategy is generated based on the characteristic data of the photovoltaic inverter, and the control strategy is transmitted to the corresponding smart IoT meter for S5. In this embodiment, the control of the power supply in the distribution area is all based on the output power of the photovoltaic inverter. In practical applications, in addition to adjusting the output power of the photovoltaic inverter, the power indicators of the distribution area can also be controlled by adjusting the phase line connected to the grid by the photovoltaic inverter, or by adjusting the three-phase output power at the output end of the distribution area.

[0083] The method for generating the control strategy for the output power of the photovoltaic inverter is as follows:

[0084] S31: Calculate the total power and the over-limit ratio of three-phase imbalance in the current transformer area.

[0085] The calculation method for the excess ratio is as follows:

[0086]

[0087] in, This represents the percentage of the total power output of the transformer substation that exceeds the limit. This represents the proportion of the three-phase unbalance that exceeds the limit. Power threshold This is the threshold for three-phase imbalance.

[0088] The excess ratio characterizes the hazard to the safe operation of a power distribution area caused by exceeding power consumption limits. The higher the excess ratio, the greater the potential safety hazard. Timely regulation of power consumption indicators in the distribution area can prevent power accidents and avoid property losses to photovoltaic users or power companies.

[0089] S32: Calculate the control coefficient of the photovoltaic inverter connected to each phase based on the over-limit ratio and the total voltage and total current of all photovoltaic inverters.

[0090] When all photovoltaic inverters are synchronously regulated, i.e., the same regulation coefficient is used for regulation, the general calculation method for the regulation coefficient K is as follows:

[0091]

[0092] in, These represent the total current of the photovoltaic inverters in phases A, B, and C, respectively. While overall control can adjust the power indicators of the distribution area to within the threshold range, the overall power loss from photovoltaic inverter regulation is relatively high, making it difficult to guarantee the maximum benefit for photovoltaic users. Therefore, it is necessary to separately control the photovoltaic inverters of each phase to achieve a balance between the safe operation of the distribution area and the interests of photovoltaic users.

[0093] When the photovoltaic inverters on each phase are controlled separately, the calculation formulas for the control coefficients K1, K2, and K3 of the photovoltaic inverters on each phase are as follows:

[0094] when At that time, the formula for calculating the control coefficient is as follows:

[0095]

[0096] in, These are the total currents of the photovoltaic inverters for phases A, B, and C, respectively.

[0097] Three-phase imbalance before regulation Represented as:

[0098]

[0099] The three-phase imbalance after regulation It can be represented as:

[0100]

[0101] in, In order to be in The total current of the photovoltaic inverter on the corresponding phase, In order to be in The total current of the photovoltaic inverter on the corresponding phase.

[0102] The change in the three-phase imbalance compared to before regulation is... for:

[0103]

[0104] After simplification, we get:

[0105]

[0106] Since K≤1, Therefore, we can conclude that:

[0107]

[0108] Assuming the three-phase currents of the non-photovoltaic inverters in the distribution area are balanced, denoted as I0, then:

[0109]

[0110] because It can be known that This means that the three-phase imbalance after adjustment is less than the three-phase imbalance before adjustment. Therefore, when only the total power of the distribution area exceeds the limit, adjusting the overall coefficient of the photovoltaic inverter is sufficient to ensure that both the total power of the distribution area and the three-phase imbalance are within the threshold range.

[0111] when At that time, the formula for calculating the control coefficient K is as follows:

[0112]

[0113] Wherein, K1, K2, and K3 are the control coefficients for phase A, phase B, and phase C, respectively. This represents the average current of phases A, B, and C.

[0114] Due to the control coefficient Since the total power of the three-phase circuit is equal to the sum of the power of each phase, the total power of the distribution area will not increase after the photovoltaic inverters of each phase are adjusted. Therefore, it is only necessary to adjust the three-phase imbalance to ensure that the total power of the distribution area and the three-phase imbalance are both within the threshold range.

[0115] when At that time, the formula for calculating the control coefficient K is as follows:

[0116]

[0117] in, These are the total voltages of the photovoltaic inverters for phases A, B, and C, respectively.

[0118] When both the total power and the three-phase imbalance in the distribution area exceed the threshold, it is necessary to regulate both the total power and the three-phase imbalance simultaneously. While meeting the regulation objectives, the output power of the photovoltaic inverter should be kept as high as possible to ensure the maximum benefit of photovoltaic users.

[0119] S33: Set the control strategy for each photovoltaic inverter based on the control coefficient and the characteristic information of each photovoltaic inverter.

[0120] The control strategy for each photovoltaic inverter is as follows:

[0121] S331: The master server sets the priority of the control mode for each photovoltaic inverter. The priority indicates the order in which the photovoltaic inverter adopts the control mode. Each photovoltaic inverter may support one or more control modes. For example, when any photovoltaic inverter supports both active power regulation and reactive power regulation, the priority is set according to the specifications of the photovoltaic inverter, such as prioritizing active power regulation.

[0122] S332: A control strategy for each photovoltaic inverter is generated based on the control coefficient for each phase, the phase lines connected to each photovoltaic inverter, and their priorities. For any photovoltaic inverter, its control strategy can be expressed as: K i M j (i, j = (1, 2, 3)). Where K i M represents the photovoltaic inverter control coefficient in the phase line where the photovoltaic inverter is located. j This indicates the preferred regulation mode for the photovoltaic inverter. Let M1 be active power regulation, M2 be reactive power regulation, and M3 be power factor regulation. If the regulation strategy of a photovoltaic inverter is K1M1, it means that the photovoltaic inverter is connected to phase A, its regulation coefficient is K1, and active power regulation is preferred.

[0123] Please combine Figure 2 , it is Figure 1 A flowchart of emergency handling methods when a smart IoT meter or inverter malfunctions.

[0124] S4: Based on the feedback information from the smart IoT meter, analyze the cause of the fault and make the following decisions:

[0125] (i) If a smart IoT meter malfunctions, a nearby smart IoT meter will be used to perform the control, and the process will return to S2. Record the logical addresses of all malfunctioning smart IoT meters and send a maintenance request.

[0126] When a smart IoT meter A malfunctions, it cannot communicate or exchange data with the photovoltaic inverter. If the master server does not receive response data from smart IoT meter A within a certain time period, it automatically generates a fault signal. The fault signal includes the logical address of smart IoT meter A and the cause of the fault. The master server sends a maintenance request to the staff and sends the fault signal to the staff, thereby reminding them to maintain smart IoT meter A in a timely manner and improving the efficiency of smart IoT meter fault diagnosis. Communication with the photovoltaic inverter is then achieved using a nearby smart IoT meter B. The master server locates the nearest smart IoT meter B based on the logical address of the faulty smart IoT meter A and sends the photovoltaic inverter's file information to smart IoT meter B. The file information includes the photovoltaic inverter's coding information, replacement instructions, setting data, and communication protocol. Smart IoT meter B acknowledges receipt of the replacement instructions and then communicates with the corresponding photovoltaic inverter according to the communication protocol and coding information, thereby sending the setting data to the corresponding photovoltaic inverter. The photovoltaic inverter completes the control according to the set data and sends the setting response data to the smart IoT meter B. The smart IoT meter B forwards the setting response data to the main station server.

[0127] (ii) If multiple photovoltaic inverters are faulty, suspend the grid connection of all faulty photovoltaic inverters and return to S2. Record the logical addresses of all faulty photovoltaic inverters and send a maintenance request.

[0128] When a smart meter interacts with a photovoltaic (PV) inverter or controls the PV inverter, if the smart meter does not receive a response from the PV inverter within a certain time period, it generates a PV inverter fault signal. The PV inverter fault signal includes the PV inverter's logical address and the cause of the fault. The smart meter sends the PV inverter fault signal to the master server, which generates a shutdown command and sends it to the smart meter. The smart meter disconnects the PV inverter from the internet. Simultaneously, the master server sends a message to the PV user, reminding them to proactively shut down the PV inverter or check if it is already shut down, and prompting them to repair the PV inverter as soon as possible. The master server also sends a PV inverter fault signal to staff to remind them to prepare for repairs.

[0129] S5: After receiving the control strategy, the smart IoT meter adjusts the operating status of the photovoltaic inverter according to the control strategy. Return to S1.

[0130] After generating the control strategy, the master server sends it to the smart IoT meter in the form of archive information. The smart IoT meter receives and parses the archive information, generates the setting data for the control strategy, and sends it to the corresponding photovoltaic inverter. After receiving the setting data, the photovoltaic inverter modifies its internal register parameters, thereby controlling the output power of the photovoltaic inverter. After modifying the register parameters, the photovoltaic inverter automatically generates setting response data and sends it to the smart IoT meter. The smart IoT meter forwards the setting response data to the master server, which analyzes whether the corresponding photovoltaic inverter has completed the control.

[0131] This embodiment provides a power regulation method for photovoltaic (PV) distribution areas based on smart meters. The method collects characteristic data from PV inverters using smart meters. When the power consumption index of a distribution area exceeds limits, it formulates corresponding regulation strategies based on the regulation methods supported by each PV inverter, the current power data of the distribution area, and the characteristic data of the PV inverters. Then, the smart meters perform overall regulation of all PV inverters to restore the power consumption index of the distribution area to the set threshold range, thus resolving the potential safety risks to the power supply operation of the distribution area caused by disorderly grid connection by PV users. Furthermore, through precise communication between the main station server, smart meters, and PV inverters, faults in smart meters or PV inverters can be detected promptly, and emergency strategies can be implemented to maintain the accuracy of power monitoring or regulation of PV inverters, thereby avoiding property losses for PV users or power companies.

[0132] Please combine Figure 3 It is adopted Figure 1 This document presents a schematic diagram of a smart meter-based power control system for transformer substations. To address the challenge of precise power control in existing transformer substation power management systems that include photovoltaic inverters, this embodiment also provides a smart meter-based power control system. The power control system includes a data acquisition module, a computation module, a decision-making module, a coding module, and a photovoltaic inverter control module.

[0133] The acquisition module is used for: (1) acquiring characteristic data of the photovoltaic inverter. The characteristic data of the photovoltaic inverter includes the voltage and current output by the photovoltaic inverter in real time. The acquisition module can be a measurement circuit, measurement element or measurement device, or a device or program with communication function. It obtains the characteristic data information stored in real time by interacting with the registers in the photovoltaic inverter.

[0134] (2) Collect power data for the distribution area. Power data includes: total three-phase voltage, total three-phase current, voltage of each phase, and current of each phase. The power data of the distribution area is used to calculate the power index of the distribution area. The power data of the distribution area exceeding the preset threshold is a prerequisite for the power regulation of the distribution area.

[0135] The calculation module is used for: (1) calculating power indicators based on power data. Power indicators include the total power and three-phase imbalance of the transformer area. The power indicators of the transformer area generally include total voltage, total current, total power, three-phase imbalance and harmonics. Among them, the power indicators that can be adjusted by regulating the photovoltaic inverter and that best reflect the power safety index of the transformer area include total power and three-phase imbalance.

[0136] The current total power and three-phase imbalance of the transformer area can be expressed as follows:

[0137]

[0138] Where U is the total three-phase voltage and I is the total three-phase current. For power factor, For three-phase imbalance, For I A I B and I C The maximum value in, For I A I B and I C The minimum value in, I A I B and I C These are the currents for phases A, B, and C of the transformer substation, respectively.

[0139] (2) Calculate the control coefficient of each photovoltaic inverter based on the current power index, the preset power index threshold and the characteristic data of the photovoltaic inverter.

[0140] Based on the current exceedance of power consumption limits, the calculation formulas for the control coefficients K1, K2, and K3 of the photovoltaic inverter on each phase are as follows:

[0141] when hour,

[0142]

[0143] when At that time, the formula for calculating the control coefficient is as follows:

[0144]

[0145] Wherein, K1, K2, and K3 are the control coefficients for phase A, phase B, and phase C, respectively. This represents the average current of phases A, B, and C.

[0146] when At that time, the formula for calculating the control coefficient is as follows:

[0147]

[0148] in, These are the total voltages of the photovoltaic inverters for phases A, B, and C, respectively.

[0149] The decision module is used to: (1) determine whether the current power index exceeds the preset threshold. If it does not exceed the threshold, the current operating state of the photovoltaic inverter is maintained. If it exceeds the threshold, an over-limit signal is output. After calculating the substation index, the calculation module sends the calculation result to the decision module. The decision module compares the calculation result with the pre-stored substation power index threshold to determine whether the current substation power index exceeds the threshold. When the threshold is exceeded, the photovoltaic inverter needs to be regulated. The decision module outputs an over-limit signal to the calculation module, and then the calculation module calculates the regulation coefficient of each photovoltaic inverter.

[0150] (2) When the power index exceeds the preset threshold, determine whether the smart IoT meter has performed three photovoltaic inverter controls within a time period. If it has performed three controls, output a fault signal. If it has not performed three controls, output a control signal. Generally, after one control of the photovoltaic inverter, if the number of newly added or suspended photovoltaic inverters is small and has no significant impact on the overall power index of the distribution area, the power index of the distribution area can be restored to the normal range with a single control. If the control objective is not achieved after three controls, it can be considered that the smart IoT meter or photovoltaic inverter has malfunctioned, resulting in some controls not being implemented. Therefore, the decision module outputs a fault signal for emergency handling. If three controls are not performed within the preset period, continue to output a control signal to control the photovoltaic inverter.

[0151] (3) After outputting a fault signal, determine the cause of the fault based on the changes in the photovoltaic inverter. If a smart meter fault exists, output a smart meter fault signal. If multiple photovoltaic inverters are faulty, output a photovoltaic inverter fault signal. If a smart meter fault exists, use a nearby smart meter to perform the control. Record the logical addresses of all faulty smart meters and send a maintenance request. If multiple photovoltaic inverters are faulty, suspend the grid connection of all faulty photovoltaic inverters. Record the logical addresses of all faulty photovoltaic inverters and send a maintenance request.

[0152] The encoding module is used to encode both the smart IoT meter and the photovoltaic inverter to achieve precise communication between them. The encoded information generated after encoding the smart IoT meter or photovoltaic inverter includes not only the logical address of the photovoltaic inverter or smart IoT meter, but also the communication protocol between them, thus enabling accurate communication. In the event of a fault in the photovoltaic inverter or smart IoT meter, the actual location of the photovoltaic inverter or smart IoT meter can be accurately located using the encoded information, improving maintenance efficiency.

[0153] The photovoltaic inverter control module is used to adjust the output power of each photovoltaic inverter based on its control coefficient. After the calculation module calculates the control coefficient for each photovoltaic inverter, it sends the coefficient to the photovoltaic inverter control module. The photovoltaic inverter control module then generates a control strategy for each photovoltaic inverter based on pre-stored control methods and the control coefficient, and subsequently controls the output power of the photovoltaic inverter by sending setting data.

[0154] Example 2

[0155] To facilitate user operation, this embodiment deploys a smart meter-based substation power control system within a computer device, resulting in a smart meter-based substation power control device. The substation power control device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. Each functional module in the smart meter-based substation power control device is deployed using the aforementioned substation power control system method. When the processor executes the computer program, it implements the steps of the smart meter-based substation power control method described above, thereby enabling precise control of the photovoltaic inverter when the substation power index exceeds limits.

[0156] The computer device can be a smartphone, tablet, laptop, desktop computer, rack server, blade server, tower server, or cabinet server (including standalone servers or server clusters composed of multiple servers), etc., capable of executing programs. The computer device in this embodiment includes, but is not limited to, a memory and a processor that can communicate with each other via a system bus.

[0157] In this embodiment, the memory (i.e., the readable storage medium) includes flash memory, hard disk, multimedia card, card-type memory (e.g., SD or DX memory), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, disk, optical disk, etc. In some embodiments, the memory can be an internal storage unit of a computer device, such as the hard disk or RAM of the computer device. In other embodiments, the memory can also be an external storage device of the computer device, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the computer device. Of course, the memory can also include both internal storage units and external storage devices of the computer device. In this embodiment, the memory is typically used to store the operating system and various application software installed on the computer device. In addition, the memory can also be used to temporarily store various types of data that have been output or will be output.

[0158] In some embodiments, the processor may be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other data processing chip. This processor is typically used to control the overall operation of a computer device. In this embodiment, the processor is used to run program code stored in memory or process data to implement the steps of the above-described method for regulating the power distribution area based on smart meters, thereby enabling precise regulation of the photovoltaic inverter when the power consumption index of the distribution area exceeds the limit.

[0159] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0160] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for regional power control based on smart IoT meters, characterized in that, The control method includes the following process: S1: The smart IoT meter collects characteristic data of the photovoltaic inverter according to a preset cycle and transmits the characteristic data to the main station server; the characteristic data includes the output voltage and output current of the photovoltaic inverter; S2: The main station server collects power data of the transformer area through a measuring device; Calculate the current power index of the transformer area based on the power data, and determine whether the power index exceeds a preset threshold; if so, proceed to step S3. Otherwise, return to S1; wherein, the power data includes: total three-phase voltage, total three-phase current, voltage of each phase and current of each phase; the power indicators include the total power of the transformer area and the three-phase imbalance. S3: Determine whether the smart IoT meter has performed three photovoltaic inverter controls within a time period, and make the following decision: (i) If so, the smart IoT meter generates a fault signal and sends the fault signal to the main station server to perform S4; (ii) Otherwise, the main station server generates a corresponding control strategy based on the feature data and the power data, and transmits the control strategy to the corresponding smart IoT meter for S5; The method for generating the control strategy is as follows: S31: Calculate the total power and the over-limit ratio of the three-phase imbalance of the current transformer area based on the total three-phase voltage, the total three-phase current, the partial voltage of each phase, and the partial current of each phase. S32: Calculate the control coefficient of the photovoltaic inverter connected to each phase line based on the over-limit ratio and the output voltage and output current of each photovoltaic inverter; wherein, the control coefficient is the ratio of the output power of the photovoltaic inverter after control to the output power of the photovoltaic inverter before control; S33: Set the control strategy for each photovoltaic inverter based on the control coefficient and the characteristic information of each photovoltaic inverter; S4: The master server receives and analyzes the fault signal and makes the following decision: (i) If a smart IoT meter is faulty, a nearby smart IoT meter will be used to perform the control, and the process will return to S2; the logical addresses of all faulty smart IoT meters will be recorded, and a maintenance request will be sent. (ii) If multiple photovoltaic inverters are faulty, suspend the grid connection of all faulty photovoltaic inverters and return to S2; record the logical addresses of all faulty photovoltaic inverters and send a maintenance request; S5: After receiving the control strategy, the smart IoT meter controls the operating status of each photovoltaic inverter according to the control strategy; then returns to S1.

2. The method for power regulation of distribution areas based on smart meters according to claim 1, characterized in that, In S1, the smart IoT meter and the photovoltaic inverter verify each other through the archive information, thereby realizing accurate data interaction between the smart IoT meter and the photovoltaic inverter; the archive information is established by the main station server; The file information includes the coding information and characteristic information of the photovoltaic inverter; the coding information is automatically generated according to the order in which each photovoltaic inverter's file is established, and each coding information is unique; the characteristic information includes the control methods supported by the photovoltaic inverter; the control methods include one or more of active power regulation, reactive power regulation, and power factor regulation.

3. The method for power regulation of distribution areas based on smart meters according to claim 1, characterized in that, In S2, the calculation method for the three-phase unbalance of the transformer area is as follows: in, For three-phase imbalance, For I A I B and I C The maximum value in, For I A I B and I C The minimum value in, I A I B and I C These are the currents for phases A, B, and C of the transformer substation, respectively.

4. The method for power regulation of distribution areas based on smart meters according to claim 1, characterized in that, In S33, the method for generating the control strategy for each photovoltaic inverter is as follows: S331: The master server sets the priority of the control mode for each photovoltaic inverter; the priority represents the order in which the photovoltaic inverter preferentially adopts the control mode; S332: Generate a control strategy for each photovoltaic inverter based on the control coefficient of each phase, the phase line connected to each photovoltaic inverter, and the priority.

5. A power control system for distribution transformers based on smart meters, which employs the power control method for distribution transformers based on smart meters as described in any one of claims 1 to 4, characterized in that, It includes: The data acquisition module is used for: (1) acquiring characteristic data of the photovoltaic inverter; (2) Collect power data for the transformer substation; The calculation module is used for: (1) calculating the power index based on the power data; the power index includes the total power of the transformer area and the three-phase imbalance; (2) calculating the control coefficient of each photovoltaic inverter based on the current power index, the preset power index threshold and the characteristic data of the photovoltaic inverter; The decision module is used to: (1) determine whether the current power index exceeds the preset threshold; If the limit is not exceeded, the current operating status of the photovoltaic inverter will be maintained; If it exceeds the limit, an over-limit signal is output; (2) When the power index exceeds the preset threshold, it is determined whether the smart IoT meter has performed photovoltaic inverter regulation three times within a time period; if it has been performed three times, a fault signal is output. If the operation is not performed three times, the control signal is output; (3) After the fault signal is output, the cause of the fault is determined based on the change of the photovoltaic inverter. If there is a smart meter fault, the smart meter fault signal is output; if there are multiple photovoltaic inverter faults, the photovoltaic inverter fault signal is output. The encoding module is used to encode the smart IoT meter and the photovoltaic inverter respectively to achieve accurate communication between the smart IoT meter and the photovoltaic inverter; A photovoltaic inverter control module is used to adjust the output power of each photovoltaic inverter according to the control coefficient of each photovoltaic inverter.

6. A power control device for transformer substations based on a smart IoT meter, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, Each functional module in the smart IoT meter-based distribution area power control device is deployed in the manner described in claim 5 as a distribution area power control system. When the processor executes the computer program, it implements the steps of the smart IoT meter-based distribution area power control method as described in any one of claims 1 to 4, thereby enabling precise control of the photovoltaic inverter when the distribution area power index exceeds the limit.

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