Voltage regulation method and system for single 10kV power transmission line

Abstract

The invention relates to a voltage regulation method and system for a single 10kV power transmission line. The method comprises the following steps: predicting load and photovoltaic conditions in a power supply range of the single 10kV power transmission line; arranging operation modes of all photovoltaic power generation monomers and energy storage monomers in a power supply range of a single 10kV power transmission line according to prediction results of load and photovoltaic conditions; setting a response cluster of a plurality of levels, wherein the response cluster is provided with a plurality of photovoltaic power generation monomers and energy storage monomers; the voltage change condition of the 10kV power transmission line is monitored in real time; according to the voltage change condition, the photovoltaic power generation monomers and the energy storage monomers of the corresponding response clusters are selected to adjust the voltage of the 10kV power transmission line; according to the invention, the photovoltaic and energy storage operation benefits are improved on the premise of ensuring the power supply reliability of the whole line.

Description

Technical Field

[0001] The present invention relates to the technical field of power transmission lines, and in particular to a voltage regulation method and system for a single 10kV power transmission line. Background Art

[0002] Within the power supply range of a 10kV transmission line, with the large-scale construction and operation of a large number of 10kV and 380V distributed photovoltaic and energy storage, it has a great impact on the safe and stable operation of the 10kV distribution network, especially power reverse transmission and node overvoltage. The overvoltage problem will directly affect the safe operation of the distribution network and increase the amount of abandoned photovoltaic power. The voltage control strategy of the distribution network can be roughly divided into centralized voltage regulation and distributed voltage regulation. Among them, centralized voltage regulation uses the global allocation of the distribution network to coordinate the available resources in the system, which is suitable for occasional voltage over-limit situations; distributed voltage regulation takes local consumption as the central idea and regulates the area of ​​the voltage over-limit node, which is relative to centralized voltage regulation. For distributed voltage regulation, existing research introduces the concept of cluster to regulate the distribution network. A cluster is composed of several electrically similar or complementary nodes, as well as distributed power sources, distributed energy storage, loads and other control devices in the area. Dividing strongly coupled nodes into clusters, clusters can better divide the boundaries of each area of ​​distributed energy storage voltage regulation. Among the existing control strategies for voltage regulation by dividing clusters, most of the conventional voltage regulation methods still focus on mobilizing the reactive power regulation capacity of the system, which cannot fundamentally solve the waste of photovoltaic power generation and will also lead to the loss of conventional voltage regulation resources after the system is disturbed. These cluster controls are mainly aimed at distribution networks with multiple transmission lines and cannot efficiently regulate a single 10kV transmission line. Summary of the invention

[0003] The present invention solves the problem that the prior art cannot efficiently regulate a certain 10kV transmission line and there is a waste of photovoltaic power generation, and proposes a voltage regulation method and system for a single 10kV transmission line, which improves the photovoltaic and energy storage operation efficiency while ensuring the power supply reliability of the entire line.

[0004] In order to achieve the above objectives, the following technical solutions are proposed: A voltage regulation method for a single 10kV transmission line comprises the following steps: S1, predict the load and photovoltaic conditions within the power supply range of a single 10kV transmission line; S2, arrange the operation mode of all photovoltaic power generation units and energy storage units within the power supply range of a single 10kV transmission line according to the prediction results of load and photovoltaic conditions; S3, setting a plurality of levels of response clusters, wherein the response clusters are provided with a plurality of photovoltaic power generation units and energy storage units; S4, real-time monitoring of voltage changes of 10kV transmission lines; S5, according to the voltage change, select the photovoltaic power generation unit and energy storage unit of the corresponding response cluster to adjust the voltage of the 10kV transmission line.

[0005] The present invention pre-arranges the operation mode of energy storage cells and photovoltaic power generation cells according to the daily load and photovoltaic forecast conditions, plans the energy storage charging and discharging plan and the photovoltaic capacity allowed to be connected to the grid in advance, and formulates the cluster control plan for the day for different voltage change ranges. When the line voltage changes, the present invention arranges clusters of different sizes in combination with the daily operation mode to adjust the line voltage, thereby improving the photovoltaic and energy storage operation efficiency while ensuring the reliability of power supply for the entire line. The present invention is aimed at a 10kV transmission line power supply range, including distributed photovoltaic and energy storage resources with a voltage level of 10kV and below. When the voltage of the transmission line fluctuates abnormally due to abnormal changes in photovoltaics, energy storage, and user loads, the voltage regulation strategy formulated by the management system quickly responds to voltage changes, adjusts the photovoltaic and electric energy storage operation status in time, and improves the voltage quality of users within the power supply range.

[0006] Preferably, the response clusters are differentiated according to the magnitude of abnormal voltage fluctuations of the 10 kV transmission line, and are divided into four levels from large to small.

[0007] The present invention distinguishes four levels of response clusters according to the magnitude of abnormal voltage fluctuation of the 10kV transmission line, namely, a first response cluster, a second response cluster, a third response cluster and a fourth response cluster from large to small.

[0008] Preferably, when the voltage change exceeds 10% of the allowable voltage value of the 10kV transmission line, the response cluster is the first response cluster; when the voltage change is between 5% and 10% of the allowable voltage value of the 10kV transmission line, the response cluster is the second response cluster; when the voltage change is between 2% and 5% of the allowable voltage value of the 10kV transmission line, the response cluster is the third response cluster; when the voltage change is less than 2% of the allowable voltage value of the 10kV transmission line, the response cluster is the fourth response cluster.

[0009] If the voltage fluctuation value is greater than 10% of the allowable voltage value of the 10kV transmission line, it is the first response cluster; at this time, the 10kV photovoltaic cluster, 380V photovoltaic cluster, 10kV energy storage cluster and 380V energy storage cluster all participate in the regulation of the first response cluster.

[0010] If the voltage fluctuation value is between 5% and 10% of the allowable voltage value of the 10kV transmission line, it is the second response cluster; at this time, the 10kV photovoltaic cluster and the 10kV energy storage cluster participate in the regulation of the second response cluster.

[0011] If the voltage fluctuation value is between 2% and 5% of the allowable voltage value of the 10kV transmission line, it is the third response cluster; at this time, the 380V photovoltaic cluster, 380V energy storage cluster, 10kV photovoltaic cluster and part of the 10kV energy storage cluster participate in the regulation of the third response cluster, and the 380V photovoltaic cluster and 380V energy storage cluster are used for regulation first.

[0012] If the voltage fluctuation value is lower than 2% of the allowable voltage value of the 10kV transmission line, it is the fourth response cluster; at this time, the 380V photovoltaic cluster and the 380V energy storage cluster all participate in the regulation of the fourth response cluster.

[0013] The present invention is aimed at a 10kV transmission line. When there are 10kV photovoltaic and energy storage as well as 380V photovoltaic and energy storage within its power supply range, according to the daily load and photovoltaic forecast results within the power supply range, the management system formulates an operation plan for the distributed photovoltaic and various energy storage within its power supply range. When the line voltage changes, the cluster classification of the day is determined according to the voltage change, and the working hours and working states of the distributed photovoltaic and various energy storage are reasonably arranged. Under the premise of ensuring the power supply reliability of the entire line, the operation efficiency of photovoltaic and energy storage is improved.

[0014] Preferably, the S5 specifically comprises the following steps: S51, determine whether the voltage change exceeds 10% of the allowable value, if so, start the first response cluster to adjust the distribution network, if not, proceed to S52; S52, determine whether the voltage change exceeds 5% of the allowable value, if so, start the second response cluster to adjust the distribution network, if not, proceed to S53; S53, determining whether the voltage variation exceeds 2% of the allowable value, if so, starting the third response cluster to adjust the distribution network, if not, starting the fourth response cluster to adjust the distribution network.

[0015] S5 of the present invention specifically comprises the following steps: S51, determine whether the voltage change exceeds 10% of the allowable value of the 10kV transmission line. If so, use the first response cluster to adjust the 10kV transmission line. If not, proceed to S52; S52, determining whether the voltage change exceeds 5% of the allowable value of the 10kV transmission line, if so, using the second response cluster to adjust the 10kV transmission line, if not, proceeding to S53; S53, determining whether the voltage change exceeds 2% of the allowable value of the 10kV transmission line, if so, using the third response cluster to adjust the 10kV transmission line, if not, starting the fourth response cluster to adjust the 10kV transmission line.

[0016] Preferably, S1 specifically includes the following steps: obtaining the real-time status of the load and photovoltaic power within the power supply range of a single 10kV transmission line in real time, and predicting the power status of photovoltaic power generation units and energy storage units based on the real-time status of the load and photovoltaic power, wherein the power status is power shortage or sufficient power.

[0017] S1 of the present invention specifically includes the following steps: first, the real-time conditions of photovoltaics and loads within the power supply range of a single 10kV transmission line are obtained in real time, and the power conditions of energy storage cells and photovoltaic power generation cells are predicted according to the real-time conditions of photovoltaics and loads, and the prediction result is power shortage or sufficient power.

[0018] Preferably, S2 specifically includes the following steps: when the power situation of the photovoltaic power generation unit and the energy storage unit is power shortage, their operation mode is arranged to the charging mode, and the 10kV transmission line charges them; when the power situation of the photovoltaic power generation unit and the energy storage unit is sufficient, their operation mode is arranged to the discharging mode, and they discharge the 10kV transmission line.

[0019] S2 of the present invention specifically includes the following steps: if the power situation of the energy storage cell and the photovoltaic power generation cell is power shortage, then the operation mode is set to the charging mode, and the power shortage energy storage cell and the photovoltaic power generation cell are charged by using the 10kV transmission line; if the power situation of the energy storage cell and the photovoltaic power generation cell is sufficient, then the operation mode is set to the discharging mode, and the energy storage cell and the photovoltaic power generation cell with sufficient power are used to discharge the 10kV transmission line.

[0020] Preferably, the S5 also includes judging the operation mode of a single 10kV transmission line according to the voltage change. When the voltage of the single 10kV transmission line is too low, the photovoltaic power generation cells and energy storage cells in the corresponding response cluster that are in the discharge mode discharge the single 10kV transmission line; when the voltage of the single 10kV transmission line is too high, the single 10kV transmission line charges the photovoltaic power generation cells and energy storage cells in the corresponding response cluster that are in the charging mode.

[0021] S5 of the present invention also includes judging the operating mode of a single 10kV transmission line according to the voltage change. If the voltage change of the single 10kV transmission line is that the voltage is too low, the energy storage cells and photovoltaic power generation cells in the discharge mode in the corresponding response cluster discharge the single 10kV transmission line; if the voltage change of the single 10kV transmission line is that the voltage is too high, the single 10kV transmission line charges the energy storage cells and photovoltaic power generation cells in the charging mode in the corresponding response cluster.

[0022] A voltage regulation system for a single 10kV transmission line, using the above-mentioned voltage regulation method for a single 10kV transmission line, comprises: A main control module, wherein the main control module is provided with a voltage judgment unit and a load and photovoltaic prediction unit; The operation data collection module collects the operation data of each photovoltaic power generation unit and energy storage unit in the response cluster to the load and photovoltaic prediction unit; The operation mode management module receives the prediction results output by the load and photovoltaic prediction unit, and controls the operation mode of each photovoltaic power generation unit and energy storage unit in the response cluster; The operation selection module receives the output result of the voltage judgment unit, selects the photovoltaic power generation unit and the energy storage unit of the corresponding response cluster to adjust the voltage of the 10kV transmission line according to the operation mode set by the operation mode management module; The voltage data acquisition module collects the voltage data of the 10kV transmission line to the voltage judgment unit.

[0023] The present invention is aimed at a 10kV transmission line. When there are 10kV photovoltaic and energy storage as well as 380V photovoltaic and energy storage within its power supply range, according to the daily load and photovoltaic forecast results within the power supply range, the management system formulates an operation plan for the distributed photovoltaic and various energy storage within its power supply range. When the line voltage changes, the cluster classification of the day is determined according to the voltage change, and the working hours and working states of the distributed photovoltaic and various energy storage are reasonably arranged. Under the premise of ensuring the power supply reliability of the entire line, the operation efficiency of photovoltaic and energy storage is improved.

[0024] Preferably, the response cluster is provided with a photovoltaic cluster and an energy storage cluster, the photovoltaic cluster includes a 10kV photovoltaic cluster and a 380V photovoltaic cluster, and the energy storage cluster includes a 10kV energy storage cluster and a 380V energy storage cluster.

[0025] The response cluster is provided with a photovoltaic cluster consisting of a 10kV photovoltaic cluster and a 380V photovoltaic cluster and an energy storage cluster consisting of a 10kV energy storage cluster and a 380V energy storage cluster. The present invention distinguishes four levels of response clusters according to the magnitude of abnormal voltage fluctuation of the 10kV transmission line, namely, the first response cluster, the second response cluster, the third response cluster and the fourth response cluster from large to small.

[0026] Preferably, the energy storage cluster includes electric energy storage cells, cold energy storage units and thermal energy storage cells.

[0027] The energy storage units of the energy storage cluster of the present invention can be divided into electric energy storage units, cold energy storage units and thermal energy storage units according to the storage form.

[0028] The beneficial effects of the present invention are as follows: the present invention is directed to a 10kV transmission line. When there are 10kV photovoltaic and energy storage as well as 380V photovoltaic and energy storage within its power supply range, according to the daily load and photovoltaic forecast results within the power supply range, an operation plan is formulated through the management system for distributed photovoltaic and various energy storage within its power supply range. When the line voltage changes, the cluster classification of the day is determined according to the voltage change, and the working hours and working states of distributed photovoltaic and various energy storage are reasonably arranged. Under the premise of ensuring the power supply reliability of the entire line, the operation efficiency of photovoltaic and energy storage is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a flow chart of the method of the present invention.

[0030] Figure 2 It is a system configuration diagram of the present invention. DETAILED DESCRIPTION

[0031] Embodiment 1: This embodiment proposes a voltage regulation method for a single 10kV transmission line. Figure 1 , including the following steps: S1, collects the operating data within the power supply range of a single 10kV transmission line and predicts the load and photovoltaic conditions; S1 of the present invention specifically includes the following steps: first, the real-time conditions of photovoltaics and loads within the power supply range of a single 10kV transmission line are obtained in real time, and the power conditions of energy storage cells and photovoltaic power generation cells are predicted according to the real-time conditions of photovoltaics and loads, and the prediction result is power shortage or sufficient power.

[0032] S2, according to the prediction results of load and photovoltaic conditions, set the operation mode of all energy storage units and photovoltaic power generation units within the power supply range of a single 10kV transmission line; S2 of the present invention specifically includes the following steps: if the power situation of the energy storage cell and the photovoltaic power generation cell is power shortage, then the operation mode is set to the charging mode, and the power shortage energy storage cell and the photovoltaic power generation cell are charged by using the 10kV transmission line; if the power situation of the energy storage cell and the photovoltaic power generation cell is sufficient, then the operation mode is set to the discharging mode, and the energy storage cell and the photovoltaic power generation cell with sufficient power are used to discharge the 10kV transmission line.

[0033] S3, pre-set 4 levels of response clusters, each response cluster is provided with a number of energy storage units and photovoltaic power generation units; the present invention distinguishes 4 levels of response clusters according to the magnitude of abnormal voltage fluctuation of the 10kV transmission line, which are the first response cluster, the second response cluster, the third response cluster and the fourth response cluster from large to small.

[0034] If the voltage fluctuation value is greater than 10% of the allowable voltage value of the 10kV transmission line, it is the first response cluster; at this time, the 10kV photovoltaic cluster, 380V photovoltaic cluster, 10kV energy storage cluster and 380V energy storage cluster all participate in the regulation of the first response cluster.

[0035] If the voltage fluctuation value is between 5% and 10% of the allowable voltage value of the 10kV transmission line, it is the second response cluster; at this time, the 10kV photovoltaic cluster and the 10kV energy storage cluster participate in the regulation of the second response cluster.

[0036] If the voltage fluctuation value is between 2% and 5% of the allowable voltage value of the 10kV transmission line, it is the third response cluster; at this time, the 380V photovoltaic cluster, 380V energy storage cluster, 10kV photovoltaic cluster and part of the 10kV energy storage cluster participate in the regulation of the third response cluster, and the 380V photovoltaic cluster and 380V energy storage cluster are used for regulation first.

[0037] If the voltage fluctuation value is lower than 2% of the allowable voltage value of the 10kV transmission line, it is the fourth response cluster; at this time, the 380V photovoltaic cluster and the 380V energy storage cluster all participate in the regulation of the fourth response cluster.

[0038] The present invention is aimed at a 10kV transmission line. When there are 10kV photovoltaic and energy storage as well as 380V photovoltaic and energy storage within its power supply range, according to the daily load and photovoltaic forecast results within the power supply range, the management system formulates an operation plan for the distributed photovoltaic and various energy storage within its power supply range. When the line voltage changes, the cluster classification of the day is determined according to the voltage change, and the working hours and working states of the distributed photovoltaic and various energy storage are reasonably arranged. Under the premise of ensuring the power supply reliability of the entire line, the operation efficiency of photovoltaic and energy storage is improved.

[0039] S4, real-time monitoring of the voltage fluctuation of the 10kV transmission line to obtain its voltage change; S5, select a response cluster of the corresponding level according to the voltage change, and select energy storage cells and photovoltaic power generation cells in the response cluster to adjust the voltage of the 10kV transmission line.

[0040] The present invention pre-arranges the operation mode of energy storage cells and photovoltaic power generation cells according to the daily load and photovoltaic forecast conditions, plans the energy storage charging and discharging plan and the photovoltaic capacity allowed to be connected to the grid in advance, and formulates the cluster control plan for the day for different voltage change ranges. When the line voltage changes, the present invention arranges clusters of different sizes in combination with the daily operation mode to adjust the line voltage, thereby improving the photovoltaic and energy storage operation efficiency while ensuring the reliability of power supply for the entire line. The present invention is aimed at a 10kV transmission line power supply range, including distributed photovoltaic and energy storage resources with a voltage level of 10kV and below. When the voltage of the transmission line fluctuates abnormally due to abnormal changes in photovoltaics, energy storage, and user loads, the voltage regulation strategy formulated by the management system quickly responds to voltage changes, adjusts the photovoltaic and electric energy storage operation status in time, and improves the voltage quality of users within the power supply range.

[0041] A voltage regulation system for a single 10kV transmission line, using the above-mentioned voltage regulation method for a single 10kV transmission line, referring to Figure 2 , including a main control module, an operation data acquisition module, an operation mode management module, an operation selection module and a voltage data acquisition module. The main control module is provided with a load and photovoltaic prediction unit and a voltage judgment unit. The voltage judgment unit is electrically connected to the voltage data acquisition module and the operation selection module, and is used to judge the voltage data of the 10kV transmission line collected by the voltage data acquisition module to obtain an output result. The operation selection module then selects the photovoltaic power generation unit and the energy storage unit of the corresponding response cluster according to the output result to adjust the voltage of the 10kV transmission line. The load and photovoltaic prediction unit is electrically connected to the operation data acquisition module and the operation mode management module, and is used to receive the operation data of each energy storage unit and photovoltaic power generation unit in the response cluster collected by the operation data acquisition module and obtain the prediction result. The operation mode management module is electrically connected to each energy storage unit and photovoltaic power generation unit, and controls the operation mode of each energy storage unit and photovoltaic power generation unit in the response cluster according to the prediction result. The energy storage unit of the energy storage cluster of the present invention can be divided into electric energy storage unit, cold energy storage unit and thermal energy storage unit according to the storage form. The response cluster is provided with a photovoltaic cluster consisting of a 10kV photovoltaic cluster and a 380V photovoltaic cluster and an energy storage cluster consisting of a 10kV energy storage cluster and a 380V energy storage cluster. The present invention distinguishes four levels of response clusters according to the magnitude of abnormal voltage fluctuation of the 10kV transmission line, namely, the first response cluster, the second response cluster, the third response cluster and the fourth response cluster from large to small.

[0042] The present invention is aimed at a 10kV transmission line. When there are 10kV photovoltaic and energy storage as well as 380V photovoltaic and energy storage within its power supply range, according to the daily load and photovoltaic forecast results within the power supply range, the management system formulates an operation plan for the distributed photovoltaic and various energy storage within its power supply range. When the line voltage changes, the cluster classification of the day is determined according to the voltage change, and the working hours and working states of the distributed photovoltaic and various energy storage are reasonably arranged. Under the premise of ensuring the power supply reliability of the entire line, the operation efficiency of photovoltaic and energy storage is improved.

[0043] Embodiment 2: This embodiment optimizes S5 on the basis of embodiment 1 and proposes a voltage regulation method for a single 10kV transmission line. Figure 1 , including the following steps: S1, collects the operating data within the power supply range of a single 10kV transmission line and predicts the load and photovoltaic conditions; S1 of the present invention specifically includes the following steps: first, the real-time conditions of photovoltaics and loads within the power supply range of a single 10kV transmission line are obtained in real time, and the power conditions of energy storage cells and photovoltaic power generation cells are predicted according to the real-time conditions of photovoltaics and loads, and the prediction result is power shortage or sufficient power.

[0044] S2, according to the prediction results of load and photovoltaic conditions, set the operation mode of all energy storage units and photovoltaic power generation units within the power supply range of a single 10kV transmission line; S2 of the present invention specifically includes the following steps: if the power situation of the energy storage cell and the photovoltaic power generation cell is power shortage, then the operation mode is set to the charging mode, and the power shortage energy storage cell and the photovoltaic power generation cell are charged by using the 10kV transmission line; if the power situation of the energy storage cell and the photovoltaic power generation cell is sufficient, then the operation mode is set to the discharging mode, and the energy storage cell and the photovoltaic power generation cell with sufficient power are used to discharge the 10kV transmission line.

[0045] S3, pre-set 4 levels of response clusters, each response cluster is provided with a number of energy storage units and photovoltaic power generation units; the present invention distinguishes 4 levels of response clusters according to the magnitude of abnormal voltage fluctuation of the 10kV transmission line, which are the first response cluster, the second response cluster, the third response cluster and the fourth response cluster from large to small.

[0046] If the voltage fluctuation value is greater than 10% of the allowable voltage value of the 10kV transmission line, it is the first response cluster; at this time, the 10kV photovoltaic cluster, 380V photovoltaic cluster, 10kV energy storage cluster and 380V energy storage cluster all participate in the regulation of the first response cluster.

[0047] If the voltage fluctuation value is between 5% and 10% of the allowable voltage value of the 10kV transmission line, it is the second response cluster; at this time, the 10kV photovoltaic cluster and the 10kV energy storage cluster participate in the regulation of the second response cluster.

[0048] If the voltage fluctuation value is between 2% and 5% of the allowable voltage value of the 10kV transmission line, it is the third response cluster; at this time, the 380V photovoltaic cluster, 380V energy storage cluster, 10kV photovoltaic cluster and part of the 10kV energy storage cluster participate in the regulation of the third response cluster, and the 380V photovoltaic cluster and 380V energy storage cluster are used for regulation first.

[0049] If the voltage fluctuation value is lower than 2% of the allowable voltage value of the 10kV transmission line, it is the fourth response cluster; at this time, the 380V photovoltaic cluster and the 380V energy storage cluster all participate in the regulation of the fourth response cluster.

[0050] The present invention is aimed at a 10kV transmission line. When there are 10kV photovoltaic and energy storage as well as 380V photovoltaic and energy storage within its power supply range, according to the daily load and photovoltaic forecast results within the power supply range, the management system formulates an operation plan for the distributed photovoltaic and various energy storage within its power supply range. When the line voltage changes, the cluster classification of the day is determined according to the voltage change, and the working hours and working states of the distributed photovoltaic and various energy storage are reasonably arranged. Under the premise of ensuring the power supply reliability of the entire line, the operation efficiency of photovoltaic and energy storage is improved.

[0051] S4, real-time monitoring of the voltage fluctuation of the 10kV transmission line to obtain its voltage change; S5, selecting a response cluster of the corresponding level according to the voltage change, and selecting energy storage units and photovoltaic power generation units in the response cluster to adjust the voltage of the 10kV transmission line. S5 of the present invention specifically includes the following steps: S51, determine whether the voltage change exceeds 10% of the allowable value of the 10kV transmission line. If so, use the first response cluster to adjust the 10kV transmission line. If not, proceed to S52; S52, determining whether the voltage change exceeds 5% of the allowable value of the 10kV transmission line, if so, using the second response cluster to adjust the 10kV transmission line, if not, proceeding to S53; S53, determining whether the voltage change exceeds 2% of the allowable value of the 10kV transmission line, if so, using the third response cluster to adjust the 10kV transmission line, if not, starting the fourth response cluster to adjust the 10kV transmission line.

[0052] The present invention pre-arranges the operation mode of energy storage cells and photovoltaic power generation cells according to the daily load and photovoltaic forecast conditions, plans the energy storage charging and discharging plan and the photovoltaic capacity allowed to be connected to the grid in advance, and formulates the cluster control plan for the day for different voltage change ranges. When the line voltage changes, the present invention arranges clusters of different sizes in combination with the daily operation mode to adjust the line voltage, thereby improving the photovoltaic and energy storage operation efficiency while ensuring the reliability of power supply for the entire line. The present invention is aimed at a 10kV transmission line power supply range, including distributed photovoltaic and energy storage resources with a voltage level of 10kV and below. When the voltage of the transmission line fluctuates abnormally due to abnormal changes in photovoltaics, energy storage, and user loads, the voltage regulation strategy formulated by the management system quickly responds to voltage changes, adjusts the photovoltaic and electric energy storage operation status in time, and improves the voltage quality of users within the power supply range.

[0053] A voltage regulation system for a single 10kV transmission line, using the above-mentioned voltage regulation method for a single 10kV transmission line, referring to Figure 2 , including a main control module, an operation data acquisition module, an operation mode management module, an operation selection module and a voltage data acquisition module. The main control module is provided with a load and photovoltaic prediction unit and a voltage judgment unit. The voltage judgment unit is electrically connected to the voltage data acquisition module and the operation selection module, and is used to judge the voltage data of the 10kV transmission line collected by the voltage data acquisition module to obtain an output result. The operation selection module then selects the photovoltaic power generation unit and the energy storage unit of the corresponding response cluster according to the output result to adjust the voltage of the 10kV transmission line. The load and photovoltaic prediction unit is electrically connected to the operation data acquisition module and the operation mode management module, and is used to receive the operation data of each energy storage unit and photovoltaic power generation unit in the response cluster collected by the operation data acquisition module and obtain the prediction result. The operation mode management module is electrically connected to each energy storage unit and photovoltaic power generation unit, and controls the operation mode of each energy storage unit and photovoltaic power generation unit in the response cluster according to the prediction result. The energy storage unit of the energy storage cluster of the present invention can be divided into electric energy storage unit, cold energy storage unit and thermal energy storage unit according to the storage form. The response cluster is provided with a photovoltaic cluster consisting of a 10kV photovoltaic cluster and a 380V photovoltaic cluster and an energy storage cluster consisting of a 10kV energy storage cluster and a 380V energy storage cluster. The present invention distinguishes four levels of response clusters according to the magnitude of abnormal voltage fluctuation of the 10kV transmission line, namely, the first response cluster, the second response cluster, the third response cluster and the fourth response cluster from large to small.

[0054] The present invention is aimed at a 10kV transmission line. When there are 10kV photovoltaic and energy storage as well as 380V photovoltaic and energy storage within its power supply range, according to the daily load and photovoltaic forecast results within the power supply range, the management system formulates an operation plan for the distributed photovoltaic and various energy storage within its power supply range. When the line voltage changes, the cluster classification of the day is determined according to the voltage change, and the working hours and working states of the distributed photovoltaic and various energy storage are reasonably arranged. Under the premise of ensuring the power supply reliability of the entire line, the operation efficiency of photovoltaic and energy storage is improved.

[0055] Embodiment 3: This embodiment further optimizes S5 on the basis of Embodiment 2, and proposes a voltage regulation method for a single 10kV transmission line. Figure 1 , including the following steps: S1, collects the operating data within the power supply range of a single 10kV transmission line and predicts the load and photovoltaic conditions; S1 of the present invention specifically includes the following steps: first, the real-time conditions of photovoltaics and loads within the power supply range of a single 10kV transmission line are obtained in real time, and the power conditions of energy storage cells and photovoltaic power generation cells are predicted according to the real-time conditions of photovoltaics and loads, and the prediction result is power shortage or sufficient power.

[0056] S2, according to the prediction results of load and photovoltaic conditions, set the operation mode of all energy storage units and photovoltaic power generation units within the power supply range of a single 10kV transmission line; S2 of the present invention specifically includes the following steps: if the power situation of the energy storage cell and the photovoltaic power generation cell is power shortage, then the operation mode is set to the charging mode, and the power shortage energy storage cell and the photovoltaic power generation cell are charged by using the 10kV transmission line; if the power situation of the energy storage cell and the photovoltaic power generation cell is sufficient, then the operation mode is set to the discharging mode, and the energy storage cell and the photovoltaic power generation cell with sufficient power are used to discharge the 10kV transmission line.

[0057] S3, pre-set 4 levels of response clusters, each response cluster is provided with a number of energy storage units and photovoltaic power generation units; the present invention distinguishes 4 levels of response clusters according to the magnitude of abnormal voltage fluctuation of the 10kV transmission line, which are the first response cluster, the second response cluster, the third response cluster and the fourth response cluster from large to small.

[0058] If the voltage fluctuation value is greater than 10% of the allowable voltage value of the 10kV transmission line, it is the first response cluster; at this time, the 10kV photovoltaic cluster, 380V photovoltaic cluster, 10kV energy storage cluster and 380V energy storage cluster all participate in the regulation of the first response cluster.

[0059] If the voltage fluctuation value is between 5% and 10% of the allowable voltage value of the 10kV transmission line, it is the second response cluster; at this time, the 10kV photovoltaic cluster and the 10kV energy storage cluster participate in the regulation of the second response cluster.

[0060] If the voltage fluctuation value is between 2% and 5% of the allowable voltage value of the 10kV transmission line, it is the third response cluster; at this time, the 380V photovoltaic cluster, 380V energy storage cluster, 10kV photovoltaic cluster and part of the 10kV energy storage cluster participate in the regulation of the third response cluster, and the 380V photovoltaic cluster and 380V energy storage cluster are used for regulation first.

[0061] If the voltage fluctuation value is lower than 2% of the allowable voltage value of the 10kV transmission line, it is the fourth response cluster; at this time, the 380V photovoltaic cluster and the 380V energy storage cluster all participate in the regulation of the fourth response cluster.

[0062] The present invention is aimed at a 10kV transmission line. When there are 10kV photovoltaic and energy storage as well as 380V photovoltaic and energy storage within its power supply range, according to the daily load and photovoltaic forecast results within the power supply range, the management system formulates an operation plan for the distributed photovoltaic and various energy storage within its power supply range. When the line voltage changes, the cluster classification of the day is determined according to the voltage change, and the working hours and working states of the distributed photovoltaic and various energy storage are reasonably arranged. Under the premise of ensuring the power supply reliability of the entire line, the operation efficiency of photovoltaic and energy storage is improved.

[0063] S4, real-time monitoring of the voltage fluctuation of the 10kV transmission line to obtain its voltage change; S5, selecting a response cluster of the corresponding level according to the voltage change, and selecting energy storage units and photovoltaic power generation units in the response cluster to adjust the voltage of the 10kV transmission line. S5 of the present invention specifically includes the following steps: S51, determine whether the voltage change exceeds 10% of the allowable value of the 10kV transmission line. If so, use the first response cluster to adjust the 10kV transmission line. If not, proceed to S52; S52, determining whether the voltage change exceeds 5% of the allowable value of the 10kV transmission line, if so, using the second response cluster to adjust the 10kV transmission line, if not, proceeding to S53; S53, determining whether the voltage change exceeds 2% of the allowable value of the 10kV transmission line, if so, using the third response cluster to adjust the 10kV transmission line, if not, starting the fourth response cluster to adjust the 10kV transmission line.

[0064] S5 of the present invention also includes judging the operating mode of a single 10kV transmission line according to the voltage change. If the voltage change of the single 10kV transmission line is that the voltage is too low, the energy storage cells and photovoltaic power generation cells in the discharge mode in the corresponding response cluster discharge the single 10kV transmission line; if the voltage change of the single 10kV transmission line is that the voltage is too high, the single 10kV transmission line charges the energy storage cells and photovoltaic power generation cells in the charging mode in the corresponding response cluster.

[0065] The present invention pre-arranges the operation mode of energy storage cells and photovoltaic power generation cells according to the daily load and photovoltaic forecast conditions, plans the energy storage charging and discharging plan and the photovoltaic capacity allowed to be connected to the grid in advance, and formulates the cluster control plan for the day for different voltage change ranges. When the line voltage changes, the present invention arranges clusters of different sizes in combination with the daily operation mode to adjust the line voltage, thereby improving the photovoltaic and energy storage operation efficiency while ensuring the reliability of power supply for the entire line. The present invention is aimed at a 10kV transmission line power supply range, including distributed photovoltaic and energy storage resources with a voltage level of 10kV and below. When the voltage of the transmission line fluctuates abnormally due to abnormal changes in photovoltaics, energy storage, and user loads, the voltage regulation strategy formulated by the management system quickly responds to voltage changes, adjusts the photovoltaic and electric energy storage operation status in time, and improves the voltage quality of users within the power supply range.

[0066] A voltage regulation system for a single 10kV transmission line, using the above-mentioned voltage regulation method for a single 10kV transmission line, referring to Figure 2, including a main control module, an operation data acquisition module, an operation mode management module, an operation selection module and a voltage data acquisition module. The main control module is provided with a load and photovoltaic prediction unit and a voltage judgment unit. The voltage judgment unit is electrically connected to the voltage data acquisition module and the operation selection module, and is used to judge the voltage data of the 10kV transmission line collected by the voltage data acquisition module to obtain an output result. The operation selection module then selects the photovoltaic power generation unit and the energy storage unit of the corresponding response cluster according to the output result to adjust the voltage of the 10kV transmission line. The load and photovoltaic prediction unit is electrically connected to the operation data acquisition module and the operation mode management module, and is used to receive the operation data of each energy storage unit and photovoltaic power generation unit in the response cluster collected by the operation data acquisition module and obtain the prediction result. The operation mode management module is electrically connected to each energy storage unit and photovoltaic power generation unit, and controls the operation mode of each energy storage unit and photovoltaic power generation unit in the response cluster according to the prediction result. The energy storage unit of the energy storage cluster of the present invention can be divided into electric energy storage unit, cold energy storage unit and thermal energy storage unit according to the storage form. The response cluster is provided with a photovoltaic cluster consisting of a 10kV photovoltaic cluster and a 380V photovoltaic cluster and an energy storage cluster consisting of a 10kV energy storage cluster and a 380V energy storage cluster. The present invention distinguishes four levels of response clusters according to the magnitude of abnormal voltage fluctuation of the 10kV transmission line, namely, the first response cluster, the second response cluster, the third response cluster and the fourth response cluster from large to small.

[0067] The present invention is directed to a 10kV transmission line. When there are 10kV photovoltaic and energy storage and 380V photovoltaic and energy storage within its power supply range, according to the daily load and photovoltaic forecast results within the power supply range, the distributed photovoltaic and various energy storage within its power supply range are formulated with the management system to formulate operation plans. When the line voltage changes, the cluster classification of the day is determined according to the voltage change situation, and the working hours and working states of the distributed photovoltaic and various energy storage are reasonably arranged. Under the premise of ensuring the reliability of power supply of the entire line, the photovoltaic and energy storage operation benefits are improved. The present invention can cause abnormal fluctuations in the voltage of the transmission line due to abnormal changes in photovoltaic, energy storage, and user load, and through the voltage regulation strategy formulated by the management system, it can quickly respond to voltage changes, timely adjust the photovoltaic and electric energy storage operation states, and improve the voltage quality of users within the power supply range.

[0068] Because the overvoltage problem will directly affect the safe operation of the distribution network and increase the amount of abandoned photovoltaic power. The present invention collects all photovoltaic and energy storage operation data within the power supply range of a 10kV transmission line, and combines the grid voltage operation status. The system formulates photovoltaic operation strategies such as power output\absorption strategy to the grid, electric energy storage charging and discharging strategies such as power absorption\output strategy to the grid, and cold / hot energy storage operation strategies in real time or every 5 minutes. When the voltage of the transmission line fluctuates abnormally, that is, the voltage is too high or too low, exceeding the allowable value of this line, for example, 5%, the control instructions are sent to the relevant photovoltaic stations, electric energy storage, and cold / hot energy storage stations to quickly restore the voltage of the 10kV transmission line, thereby improving the voltage quality of users within the power supply range. According to the daily load and photovoltaic forecast, the system pre-arranges the operation mode of photovoltaic, electric energy storage, and cold / hot energy storage, plans the energy storage charging and discharging plan and the photovoltaic allowed online capacity in advance, and formulates the cluster control plan for the day for different voltage change ranges. When the line voltage changes, clusters of different sizes are arranged in combination with the operation mode of the day to adjust the line voltage. For example: if the voltage change exceeds expectations by more than 10%, the entire region's photovoltaic and energy storage will be controlled in clusters; if the voltage change exceeds expectations by 5%-10%, some 10kV-connected photovoltaic and energy storage will be controlled in clusters; if the voltage change exceeds expectations by 2%-5%, some 10kV-connected photovoltaic and energy storage, and some 380V-connected photovoltaic, electric energy storage, and cold / heat energy storage will be controlled in clusters; if the voltage change exceeds expectations by less than 2%, some 380V-connected photovoltaic, electric energy storage, and cold / heat energy storage will be controlled in clusters. On the premise of ensuring the reliability of power supply for the entire line, the operational benefits of photovoltaic and energy storage will be improved.

Claims

1. A voltage regulation method for a single 10kV transmission line, characterized in that: The following steps are involved: S1, predict the load and photovoltaic conditions within the power supply range of a single 10kV transmission line; S2, arrange the operation mode of all photovoltaic power generation units and energy storage units within the power supply range of a single 10kV transmission line according to the prediction results of load and photovoltaic conditions; S3, setting a plurality of levels of response clusters, wherein the response clusters are provided with a plurality of photovoltaic power generation units and energy storage units; S4, real-time monitoring of voltage changes of 10kV transmission lines; S5, according to the voltage change, select the photovoltaic power generation unit and energy storage unit of the corresponding response cluster to adjust the voltage of the 10kV transmission line.

2. The voltage regulation method for a single 10kV transmission line according to claim 1 is characterized in that: The response clusters are differentiated according to the magnitude of abnormal voltage fluctuations of the 10 kV transmission line and are divided into four levels from large to small.

3. The voltage regulation method for a single 10kV transmission line according to claim 2 is characterized in that: When the voltage change exceeds 10% of the allowable voltage value of the 10kV transmission line, the response cluster is the first response cluster; when the voltage change is between 5%-10% of the allowable voltage value of the 10kV transmission line, the response cluster is the second response cluster; when the voltage change is between 2%-5% of the allowable voltage value of the 10kV transmission line, the response cluster is the third response cluster; when the voltage change is less than 2% of the allowable voltage value of the 10kV transmission line, the response cluster is the fourth response cluster.

4. The voltage regulation method for a single 10kV transmission line according to claim 3 is characterized in that: The S5 specifically includes the following steps: S51, determine whether the voltage change exceeds 10% of the allowable value, if so, start the first response cluster to adjust the distribution network, if not, proceed to S52; S52, determine whether the voltage change exceeds 5% of the allowable value, if so, start the second response cluster to adjust the distribution network, if not, proceed to S53; S53, determining whether the voltage variation exceeds 2% of the allowable value, if so, starting the third response cluster to adjust the distribution network, if not, starting the fourth response cluster to adjust the distribution network.

5. A voltage regulation method for a single 10kV transmission line according to any one of claims 1 to 4, characterized in that: The S1 specifically includes the following steps: real-time acquisition of the load and photovoltaic real-time conditions within the power supply range of a single 10kV transmission line, and prediction of the power conditions of photovoltaic power generation units and energy storage units based on the load and photovoltaic real-time conditions, wherein the power conditions are power shortage or sufficient power.

6. The voltage regulation method for a single 10kV transmission line according to claim 5, characterized in that: The S2 specifically includes the following steps: when the power situation of the photovoltaic power generation unit and the energy storage unit is power shortage, their operation mode is arranged to be charging mode, and the 10kV transmission line charges them; when the power situation of the photovoltaic power generation unit and the energy storage unit is sufficient, their operation mode is arranged to be discharging mode, and they discharge the 10kV transmission line.

7. A voltage regulation method for a single 10kV transmission line according to claim 6, characterized in that: The S5 also includes judging the operation mode of a single 10kV transmission line according to the voltage change. When the voltage of a single 10kV transmission line is too low, the photovoltaic power generation cells and energy storage cells in the corresponding response cluster that are in the discharge mode discharge the single 10kV transmission line; when the voltage of a single 10kV transmission line is too high, the photovoltaic power generation cells and energy storage cells in the corresponding response cluster that are in the charging mode charge the single 10kV transmission line.

8. A voltage regulation system for a single 10kV transmission line, using the voltage regulation method for a single 10kV transmission line as claimed in claim 4, characterized in that: include: A main control module, wherein the main control module is provided with a voltage judgment unit and a load and photovoltaic prediction unit; The operation data collection module collects the operation data of each photovoltaic power generation unit and energy storage unit in the response cluster to the load and photovoltaic prediction unit; The operation mode management module receives the prediction results output by the load and photovoltaic prediction unit, and controls the operation mode of each photovoltaic power generation unit and energy storage unit in the response cluster; The operation selection module receives the output result of the voltage judgment unit, selects the photovoltaic power generation unit and the energy storage unit of the corresponding response cluster to adjust the voltage of the 10kV transmission line according to the operation mode set by the operation mode management module; The voltage data acquisition module collects the voltage data of the 10kV transmission line to the voltage judgment unit.

9. A voltage regulation system for a single 10kV transmission line according to claim 8, characterized in that: The response cluster is provided with a photovoltaic cluster and an energy storage cluster, the photovoltaic cluster includes a 10kV photovoltaic cluster and a 380V photovoltaic cluster, and the energy storage cluster includes a 10kV energy storage cluster and a 380V energy storage cluster.

10. A voltage regulation system for a single 10kV transmission line according to claim 9, characterized in that: The energy storage cluster includes electric energy storage cells, cold energy storage cells and thermal energy storage cells.

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