Voltage rise suppression method for power distribution network containing photovoltaic access

Abstract

The invention provides a voltage rise suppression method for a power distribution network with photovoltaic access. The method comprises the following steps: constructing a circuit simulation model of the power distribution network; monitoring a power utilization end in the power distribution network and performing data filling on the circuit simulation model according to monitoring data; analyzing the circuit simulation model, and determining limit parameters of each photovoltaic access point; and controlling a coordination controller configured at the photovoltaic access point to act according to the limiting parameter. According to the voltage rise suppression method for the power distribution network containing photovoltaic access, the power utilization condition in the power distribution network is comprehensively analyzed, the photovoltaic access equipment is limited, the voltage rise of the power distribution network can be effectively suppressed, and the stability and safety of the power distribution network are kept.

Description

Technical Field

[0001] The present invention relates to the technical field of voltage rise suppression in distribution networks, and in particular to a method for suppressing voltage rise in distribution networks including photovoltaic access. Background Art

[0002] Photovoltaic power generation system, referred to as PV, refers to a power generation system that uses the photovoltaic effect of photovoltaic cells to directly convert solar radiation energy into electrical energy. In recent years, PV has entered rural areas, and many households have installed PV, which can feed surplus electricity back into the distribution network while meeting their own electricity needs; however, when PV is connected to the distribution network, the terminal voltage will rise, affecting the stability of the power grid. How to suppress the voltage rise of the distribution network with PV access is an important prerequisite for maintaining the stability and safety of the distribution network. Summary of the invention

[0003] One of the purposes of the present invention is to provide a method for suppressing voltage rise in a distribution network with photovoltaic access, which comprehensively analyzes the power consumption in the distribution network and restricts photovoltaic access equipment, thereby effectively suppressing the voltage rise in the distribution network and maintaining the stability and safety of the distribution network.

[0004] An embodiment of the present invention provides a method for suppressing voltage rise in a distribution network including photovoltaic access, comprising: Construct a circuit simulation model of the distribution network; Monitor the power consumption end in the distribution network and fill the circuit simulation model with data based on the monitoring data; Analyze the circuit simulation model to determine the limiting parameters of each photovoltaic access point; The coordinated controller configured at the photovoltaic access point is controlled to act according to the limit parameters.

[0005] Preferably, the steps of constructing the circuit simulation model are as follows: According to the type and parameters of the distribution network, the corresponding framework is retrieved from the preset framework library; Adjust the access position of each power terminal in the framework; Configure the power consumption terminal parameters of each power consumption terminal in the framework; Adjust the access position of each photovoltaic access point within the framework; Configure the access parameters of each PV access point within the framework.

[0006] Preferably, the monitoring data includes one or more combinations of current, electricity and power.

[0007] Preferably, the monitoring of the power consumption end in the distribution network is performed by means of a monitoring terminal arranged at an access location where the power consumption end accesses the distribution network.

[0008] Preferably, the monitoring terminal includes: a processing module, a current monitoring module, a power monitoring module and a communication module; Wherein, the communication module, the current monitoring module and the power monitoring module are electrically connected to the processing module respectively; The communication module includes: one or more combinations of 3 / 4 / 5G communication module, NB-iot communication module, WIFI communication module, RS-232 communication module and RS-485 communication module.

[0009] Preferably, the circuit simulation model is analyzed to determine the limiting parameters of each photovoltaic access point, including: Number each photovoltaic access point according to its position in the circuit simulation model; An environmental parameter set is constructed based on monitoring data of each power consumption terminal and photovoltaic access point upstream of the photovoltaic access point access location; Integrate the environmental parameter sets in numerical order to obtain the analysis data set; According to the analysis data set, the corresponding restriction parameter set is retrieved from the pre-configured analysis library; Parse the restriction parameter set to obtain the restriction parameters of each PV access point.

[0010] Preferably, the limiting parameters include: limiting voltage, and / or limiting power.

[0011] Preferably, the method for suppressing voltage rise in a distribution network including photovoltaic access further includes: Extract the suppression end along the flow direction of the distribution network; Obtain the sum of overflow parameters of photovoltaic devices corresponding to photovoltaic access points before the access point of the suppression end of the distribution network under the control of limiting parameters, and the sum of absorption parameters of other suppression ends before the access point of the suppression end of the distribution network; Calculate the difference between the total of overflow parameters and the total of absorption parameters; Determine the control parameters of the suppression end according to the calculated difference and the control parameter table configured for the corresponding suppression end; The suppression end is controlled to work according to the control parameters and the restrictions corresponding to the photovoltaic access point upstream of the suppression end are released at the same time.

[0012] Preferably, the construction steps of the inhibitory end are as follows: The power consumption terminal of the type of the power consumption terminal is a public utility and has a flexible power consumption demand as a suppression terminal.

[0013] Preferably, the method for suppressing voltage rise in a distribution network including photovoltaic access further includes: Extract features from the monitoring data of each power consumption end and photovoltaic access point of the circuit simulation model, and sort the extracted feature parameters according to the flow direction of the distribution network to form a configuration set; According to the configuration set, retrieve the corresponding configuration analysis results from the pre-configured configuration library; Parse the configuration analysis results to determine the parameters of the configured storage unit and the location where the storage unit is connected to the distribution network.

[0014] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0015] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 It is a schematic diagram of a method for suppressing voltage rise in a distribution network including photovoltaic access according to an embodiment of the present invention; Figure 2 It is a schematic diagram of another method for suppressing voltage rise in a distribution network including photovoltaic access according to an embodiment of the present invention. DETAILED DESCRIPTION

[0017] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0018] The embodiment of the present invention provides a method for suppressing voltage rise in a distribution network including photovoltaic access, such as Figure 1 As shown, including: Step 1: Construct a circuit simulation model of the distribution network; The steps for constructing the circuit simulation model are as follows: according to the type of distribution network and the grid parameters, the corresponding framework is retrieved from the preset configuration framework library; the access position of each power terminal in the framework is adjusted; the power terminal parameters of each power terminal in the framework are configured; the access position of each photovoltaic access point in the framework is adjusted; and the access parameters of each photovoltaic access point in the framework are configured. Among them, the types of distribution networks include: rural low-voltage overhead distribution network, urban low-voltage overhead distribution network, urban low-voltage cable distribution network, etc.; the grid parameters include: the number of access user terminals, grid voltage, number of photovoltaic accesses, etc.; by dragging the position of the junction point of each power terminal and the photovoltaic access point on the grid line on the framework, the position adjustment of the access position of each power terminal and the access position of each photovoltaic access point is achieved; the power terminal parameters and access parameters are configured in the input interface of the power terminal parameters or access parameters that pops up after clicking the junction point; the power terminal parameters include: the type of electrical appliances, the number of electrical appliances of each type and the power, etc.; the access parameters include: the voltage limit allowable range of access, the power allowable range, etc.; Step 2: Monitor the power consumption end in the distribution network and fill the circuit simulation model with data based on the monitoring data; The monitoring data includes one or a combination of current, power and electricity.

[0019] The monitoring of the power consumption end in the distribution network is carried out through a monitoring terminal configured at the access position where the power consumption end is connected to the distribution network. The monitoring terminal includes: a processing module, a current monitoring module, an electric quantity monitoring module and a communication module; wherein the communication module, the current monitoring module and the electric quantity monitoring module are electrically connected to the processing module respectively; the communication module includes: a 3 / 4 / 5G communication module, a NB-iot communication module, a WIFI communication module, an RS-232 communication module and an RS-485 communication module, one or more combinations thereof. The monitoring terminal can monitor the power consumption status of each power consumption end in real time, so as to better limit and adjust the photovoltaic access; Step 3: Analyze the circuit simulation model to determine the limiting parameters of each photovoltaic access point; Analyze the circuit simulation model to determine the limiting parameters of each photovoltaic access point, including: numbering each photovoltaic access point according to its position in the circuit simulation model; constructing an environmental parameter set based on the monitoring data of each power consumption end and photovoltaic access point upstream of the photovoltaic access point access position; integrating the environmental parameter set in numbering order to obtain an analysis data set; based on the analysis data set, retrieve the corresponding limiting parameter set from a pre-configured analysis library; parse the limiting parameter set to obtain the limiting parameters of each photovoltaic access point. Among them, the limiting parameters include: limiting voltage, and / or limiting power. The data in the environmental parameter set include: the average current value, maximum current value, minimum current value, etc. of each power consumption end and photovoltaic access point arranged according to the flow direction of the distribution network; each row of data in the analysis data set corresponds to a numbered environmental parameter set from top to bottom; the analysis library is constructed in advance by professionals, and the analysis data set and the limiting parameter set are associated one-to-one in the analysis library; each row in the limiting parameter set corresponds to the limiting parameter of a photovoltaic access point; Step 4: Control the actions of the coordination controller configured at the photovoltaic access point according to the restriction parameters. The specific control methods include: adding the access point voltage restriction function to the coordination controller of the photovoltaic equipment and linking it with the cloud platform; the cloud platform can set the voltage limit value of each photovoltaic access point according to the restriction parameters, and then send it to the intelligent coordination controller, thereby controlling the photovoltaic power output to suppress the voltage rise of the distribution network; in addition, the current of the photovoltaic access point can also be controlled to control the power input to the distribution network.

[0020] In one embodiment, a method for suppressing voltage rise in a distribution network including photovoltaic access is provided. Figure 2 As shown, it also includes: Step 1: Construct a circuit simulation model of the distribution network; Step 2: Monitor the power consumption end in the distribution network and fill the circuit simulation model with data based on the monitoring data; Step 3: Analyze the circuit simulation model to determine the limiting parameters of each photovoltaic access point; Step 4: controlling the action of the coordination controller configured at the photovoltaic access point according to the restriction parameters; Step 5: extract the suppression end along the flow direction of the distribution network; Step 6: Obtain the sum of overflow parameters of the photovoltaic equipment corresponding to the photovoltaic access point before the access point of the suppression end of the distribution network under the control of the limiting parameters, and the sum of the absorption parameters of other suppression ends before the access point of the suppression end of the distribution network; Step 7, calculating the difference between the total overflow parameter and the total absorption parameter; Step 8: Determine the control parameters of the suppression end according to the calculated difference and the control parameter table configured for the corresponding suppression end; Step nine: Control the suppression end to work according to the control parameters and release the restrictions corresponding to the photovoltaic access point upstream of the suppression end at the same time.

[0021] The construction steps of the inhibitory end are as follows: The power consumption terminal of the type of the power consumption terminal is a public utility and has a flexible power consumption demand as a suppression terminal.

[0022] The working principle and beneficial effects of the above technical solution are: In this embodiment, steps 1 to 4 are to monitor the distribution network and restrict the access of photovoltaic access points to achieve the lifting suppression of the distribution network. Since the restricted access means that there is a part of waste in the energy generated by the photovoltaic equipment corresponding to the photovoltaic access, through steps 5 to 9, the suppression end can be turned on to actively suppress and release the restrictions on the photovoltaic access point, effectively saving energy; the public facilities (automatic irrigation terminals, public charging piles, etc.) connected to the distribution network are used as backup options for the suppression end, and when there is a power demand in the public settings, they are converted to the suppression end; the power demand can be manually set or automatically generated by the public facilities; for example: the manual setting of the automatic irrigation terminal is that the staff configures the irrigation required today according to the needs of the farmland The automatic generation is to monitor the current farmland water level through the water level monitoring device, and query the pre-configured irrigation control table according to the difference between the target water level and the current farmland water level to determine how many hours of irrigation water is needed and under what pumping mode the irrigation is carried out; and then determine the absorption parameters according to the pumping mode and the pre-configured absorption table; therefore, when the corresponding restrictions of the photovoltaic access point are released in step nine, the overflow parameters (for example, power) with the same absorption parameters (for example, power) are used; wherein the absorption parameter is the power that can be consumed by the suppression end; the overflow parameter is the difference between the actual power generation power of the photovoltaic device and the output power of the input distribution network under the restriction parameters.

[0023] In one embodiment, the method for suppressing voltage rise in a distribution network including photovoltaic access further includes: Extract features from the monitoring data of each power consumption end and photovoltaic access point of the circuit simulation model, and sort the extracted feature parameters according to the flow direction of the distribution network to form a configuration set; the feature parameters include: the average value, maximum value and minimum value of each monitoring item in the monitoring data; the monitoring items include: current, power, voltage, etc.; According to the configuration set, the corresponding configuration analysis results are retrieved from the pre-configured configuration library; the configuration library is configured by professionals in advance, and the configuration analysis results and the configuration sets are associated one by one in the configuration library; Parse the configuration analysis results to determine the parameters of the configured storage unit and the location where the storage unit is connected to the distribution network. The configuration analysis results include: the location of the storage unit to be configured, the parameters of the storage unit (maximum storage current, maximum power, etc.).

[0024] In one embodiment, the method for suppressing voltage rise in a distribution network including photovoltaic access further includes: Determine other distribution networks within a preset distance around the distribution network; Construct a comprehensive access set of photovoltaic points connected to the distribution network and other distribution networks and a comprehensive consumption set of the power consumption end; the construction of the comprehensive access set and the comprehensive consumption set is as follows: feature extraction is performed on the monitoring data of each power consumption end and photovoltaic access point of the circuit simulation model, and the extracted feature parameters are sorted according to the flow direction of the distribution network and grouped according to the differences between the power consumption end and the photovoltaic access point to form a comprehensive access set and a comprehensive consumption set respectively; the feature parameters include: the average value, maximum value and minimum value of each monitoring item in the monitoring data; the monitoring items include: current, power, voltage, etc.; Calculate the difference between the total power of the integrated access set and the power of the integrated consumption set; Determine whether the difference of other distribution networks is complementary to the difference of the distribution network, and if so, construct an electric energy transmission station between the two distribution networks; wherein, After the electric energy transmission station is built, the comprehensive access set and comprehensive consumption set of the distribution network at both ends of the electric energy transmission station can be jointly judged before limiting the photovoltaic access point. When the judgment is passed, the electric energy transmission station is opened; Among them, the complementary judgment is: the number of times that the difference between other distribution networks and the difference between the distribution network in the preset time period is greater than or equal to zero is the maximum and greater than the preset number threshold; for example: the time period is configured as 1 month, the sampling time is 30 minutes, and the number threshold is 1400; that is, the complementary parameters are configured during the complementary judgment, and the complementary parameters are set to zero at the initial time of the time period. When the difference between other distribution networks and the difference between the distribution network is greater than or equal to zero when sampling every 30 minutes, the complementary parameters are increased by one; after one month, the complementary parameter is greater than 1400, which is greater than the number threshold, and the complementary parameters corresponding to other distribution networks are all less than this value. In actual application, the joint judgment is to determine that the sum of the comprehensive access centralized power data is less than or equal to the sum of the comprehensive consumption centralized power data.

[0025] Since the transmission configuration of the electric energy transmission station has been determined during construction, the transmission power is defined as A. When the difference is greater than A, the electric energy transmission station can be used as the power consumption end to execute steps 1 to 4 or steps 1 to 9 to complete the voltage rise suppression of the distribution network.

[0026] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for suppressing voltage rise in a distribution network with photovoltaic access, characterized in that: include: Construct a circuit simulation model of the distribution network; Monitor the power consumption end in the distribution network and fill the circuit simulation model with data based on the monitoring data; Analyze the circuit simulation model to determine the limiting parameters of each photovoltaic access point; The coordinated controller configured at the photovoltaic access point is controlled to act according to the limit parameters.

2. The method for suppressing voltage rise in a distribution network with photovoltaic access according to claim 1, characterized in that: The steps to build a circuit simulation model are as follows: According to the type and parameters of the distribution network, the corresponding framework is retrieved from the preset framework library; Adjust the access position of each power terminal in the framework; Configure the power consumption terminal parameters of each power consumption terminal in the framework; Adjust the access position of each photovoltaic access point within the framework; Configure the access parameters of each PV access point within the framework.

3. The method for suppressing voltage rise in a distribution network with photovoltaic access according to claim 1, characterized in that: The monitoring data includes one or a combination of current, power and electricity.

4. The method for suppressing voltage rise in a distribution network with photovoltaic access according to claim 1, characterized in that: The power consumption end in the distribution network is monitored by a monitoring terminal configured at the access location where the power consumption end is connected to the distribution network.

5. The method for suppressing voltage rise in a distribution network with photovoltaic access according to claim 4, characterized in that: The monitoring terminal includes: a processing module, a current monitoring module, a power monitoring module and a communication module; Wherein, the communication module, the current monitoring module and the power monitoring module are electrically connected to the processing module respectively; The communication module includes: one or more combinations of 3 / 4 / 5G communication module, NB-iot communication module, WIFI communication module, RS-232 communication module and RS-485 communication module.

6. The method for suppressing voltage rise in a distribution network with photovoltaic access according to claim 1, characterized in that: Analyze the circuit simulation model to determine the limiting parameters of each PV access point, including: Number each photovoltaic access point according to its position in the circuit simulation model; An environmental parameter set is constructed based on monitoring data of each power consumption terminal and photovoltaic access point upstream of the photovoltaic access point access location; Integrate the environmental parameter sets in numerical order to obtain the analysis data set; According to the analysis data set, the corresponding restriction parameter set is retrieved from the pre-configured analysis library; Parse the restriction parameter set to obtain the restriction parameters of each PV access point.

7. The method for suppressing voltage rise in a distribution network with photovoltaic access according to claim 1, characterized in that: The limiting parameters include: limiting voltage, and / or limiting power.

8. The method for suppressing voltage rise in a distribution network with photovoltaic access according to claim 1, characterized in that: Also includes: Extract the suppression end along the flow direction of the distribution network; Obtain the sum of overflow parameters of photovoltaic devices corresponding to photovoltaic access points before the access point of the suppression end of the distribution network under the control of limiting parameters, and the sum of absorption parameters of other suppression ends before the access point of the suppression end of the distribution network; Calculate the difference between the total of overflow parameters and the total of absorption parameters; Determine the control parameters of the suppression end according to the calculated difference and the control parameter table configured for the corresponding suppression end; The suppression end is controlled to work according to the control parameters and the restrictions corresponding to the photovoltaic access point upstream of the suppression end are released at the same time.

9. The method for suppressing voltage rise in a distribution network with photovoltaic access according to claim 8, characterized in that: The steps to construct the inhibitor are as follows: The power consumption terminal of the type of the power consumption terminal is a public utility and has a flexible power consumption demand as a suppression terminal.

10. The method for suppressing voltage rise in a distribution network with photovoltaic access according to claim 1, characterized in that: Also includes: Extract features from the monitoring data of each power consumption end and photovoltaic access point of the circuit simulation model, and sort the extracted feature parameters according to the flow direction of the distribution network to form a configuration set; According to the configuration set, retrieve the corresponding configuration analysis results from the pre-configured configuration library; Parse the configuration analysis results to determine the parameters of the configured storage unit and the location where the storage unit is connected to the distribution network.

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