Grid-connected point control method of photovoltaic power station and photovoltaic power station

Abstract

The invention discloses a grid-connected point control method of a photovoltaic power station and the photovoltaic power station, and belongs to the field of grid-connected point control. The grid-connected point control method of the photovoltaic power station comprises the following steps: acquiring a sampling electric signal acquired by each electric meter; according to the first sum of the sampling electric signals, a first power reference value corresponding to a target branch in the at least one branch and a first capacity of the target device in the at least one device correspondingly connected with the target branch, determining a target power corresponding to the target device; and controlling the target device based on the target power. According to the grid-connected point control method of the photovoltaic power station, accurate grid-connected point control can be realized, normal power supply of the power station is guaranteed, and the system control flexibility and stability are improved.

Description

Technical Field

[0001] This application belongs to the field of grid connection point control, and particularly relates to a grid connection point control method for a photovoltaic power station and a photovoltaic power station. Background Art

[0002] For a photovoltaic power station that needs to operate in parallel with the grid, in order to ensure safe, stable, and efficient operation between the power station and the grid, grid connection point control functions such as anti-countercurrent, power factor regulation, voltage, and frequency control are required. In related technologies, the grid connection point is controlled by detecting the change rate of the voltage frequency at the grid connection point with respect to the output power of the inverter module to maintain the stability of the grid connection point. However, if the control system fails, this method is likely to have a greater impact on the entire power station. Summary of the Invention

[0003] This application aims to solve at least one of the technical problems existing in the prior art. For this purpose, this application proposes a grid connection point control method for a photovoltaic power station and a photovoltaic power station, which can ensure the normal power supply of the power station, improve the flexibility and stability of system control, even if a certain control unit is abnormal, without affecting the operation of the entire power station.

[0004] In a first aspect, this application provides a grid connection point control method for a photovoltaic power station. The photovoltaic power station includes at least one branch, each branch is correspondingly connected with at least one device, each branch is connected to a grid connection point, and electric meters are respectively arranged on each branch. The method includes:

[0005] Obtaining the sampled electrical signals collected by each of the electric meters;

[0006] Determining the target power corresponding to the target device according to the first sum of the sampled electrical signals, the first power reference value corresponding to the target branch in the at least one branch, and the first capacity of the target device among the at least one device correspondingly connected to the target branch;

[0007] Controlling the target device based on the target power.

[0008] According to the grid connection point control method of this application, by arranging electric meters on each branch, precise control of each device can be achieved according to the sampled electrical signals collected by the electric meters on each branch, the first power reference value corresponding to each branch, and the first capacity of each device, so as to realize precise grid connection point control; ensure the normal power supply of the power station, and improve the flexibility and stability of system control.

[0009] According to an embodiment of this application, the determining the target power corresponding to the target device according to the first sum of the sampled electrical signals, the first power reference value corresponding to the target branch in the at least one branch, and the first capacity of the target device among the at least one device correspondingly connected to the target branch includes:

[0010] Constrain the first power reference value according to the first sum to obtain the second power reference value corresponding to the target branch;

[0011] Based on the first capacity of the target device, the second capacity corresponding to the target branch, and the second power reference value, obtain the target power corresponding to the target device; wherein, the second capacity is the sum of the capacities of all devices connected to the target branch.

[0012] According to an embodiment of the present application, the obtaining the target power corresponding to the target device based on the first capacity of the target device, the second capacity corresponding to the target branch, and the second power reference value includes:

[0013] Determine the target power corresponding to the target device based on the product of the ratio of the first capacity to the second capacity and the second power reference value.

[0014] According to an embodiment of the present application, the constraining the first power reference value according to the first sum to obtain the second power reference value corresponding to the target branch includes:

[0015] Determine the first limit power corresponding to the grid connection point according to the first sum and the target constraint threshold;

[0016] Based on the second capacity corresponding to the target branch, the third capacity corresponding to the photovoltaic power station, and the first limit power, constrain the first power reference value to obtain the second power reference value corresponding to the target branch; wherein, the third capacity is the sum of the second capacities corresponding to each branch.

[0017] According to an embodiment of the present application, the controlling the target device based on the target power includes:

[0018] Control the target device based on the target power and the actual power of the target device.

[0019] According to an embodiment of the present application, the sampled electrical signal includes active power and / or reactive power.

[0020] According to an embodiment of the present application, the first power reference value corresponding to the target branch is determined through the following steps:

[0021] Determine according to the sum of the initial power reference values corresponding to the inverters on the target branch.

[0022] Second aspect, the present application provides a connection point control device for a photovoltaic power station. The photovoltaic power station includes at least one branch circuit, each branch circuit is correspondingly connected with at least one device, each branch circuit is connected to a connection point, and an ammeter is arranged on each branch circuit; the device includes:

[0023] A first processing module, configured to obtain sampled electrical signals collected by each of the ammeters;

[0024] A second processing module, configured to determine a target power corresponding to the target device according to a first sum of the sampled electrical signals, a first power reference value corresponding to a target branch circuit among the at least one branch circuit, and a first capacity of a target device among the at least one device correspondingly connected to the target branch circuit;

[0025] A third processing module, configured to control the target device based on the target power.

[0026] According to the connection point control device of the photovoltaic power station of the present application, by arranging ammeters on each branch circuit, each device can be accurately controlled according to the sampled electrical signals collected by the ammeters on each branch circuit, the first power reference value corresponding to each branch circuit, and the first capacity of each device, so as to achieve accurate connection point control; ensure the normal power supply of the power station, and improve the flexibility and stability of system control.

[0027] Third aspect, the present application provides a photovoltaic power station, including:

[0028] At least one branch circuit, each branch circuit is correspondingly connected with at least one device, and each branch circuit is connected to a connection point;

[0029] At least one ammeter, arranged in one-to-one correspondence with the at least one branch circuit, the ammeter is arranged between the connection point and the access point where the device accesses the branch circuit, and is configured to collect sampled electrical signals corresponding to the branch circuit;

[0030] A control module, electrically connected to each of the ammeters, and configured to execute the connection point control method of the photovoltaic power station as described in the first aspect.

[0031] Fourth aspect, the present application provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the connection point control method of the photovoltaic power station as described in the first aspect above.

[0032] Fifth aspect, the present application provides a computer program product, including a computer program, and when the computer program is executed by a processor, it implements the connection point control method of the photovoltaic power station as described in the first aspect above. Description of the Drawings

[0033] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of embodiments in conjunction with the accompanying drawings, where:

[0034] Figure 1 is one of the schematic flowcharts of the grid connection point control method for a photovoltaic power station provided by an embodiment of the present application;

[0035] Figure 2 is another schematic flowchart of the grid connection point control method for a photovoltaic power station provided by an embodiment of the present application;

[0036] Figure 3 is yet another schematic flowchart of the grid connection point control method for a photovoltaic power station provided by an embodiment of the present application;

[0037] Figure 4 is still another schematic flowchart of the grid connection point control method for a photovoltaic power station provided by an embodiment of the present application;

[0038] Figure 5 is one of the schematic structural diagrams of a photovoltaic power station provided by an embodiment of the present application;

[0039] Figure 6 is another schematic structural diagram of a photovoltaic power station provided by an embodiment of the present application;

[0040] Figure 7 is yet another schematic structural diagram of a photovoltaic power station provided by an embodiment of the present application;

[0041] Figure 8 is still another schematic structural diagram of a photovoltaic power station provided by an embodiment of the present application;

[0042] Figure 9 is another schematic structural diagram of a photovoltaic power station provided by an embodiment of the present application;

[0043] Figure 10 is yet another schematic structural diagram of a photovoltaic power station provided by an embodiment of the present application;

[0044] Figure 11 is still another schematic structural diagram of a photovoltaic power station provided by an embodiment of the present application;

[0045] Figure 12 is the schematic structural diagram of the grid connection point control device for a photovoltaic power station provided by an embodiment of the present application;

[0046] Figure 13 is the schematic structural diagram of the electronic device provided by an embodiment of the present application. Detailed implementation manners

[0047] Next, the technical solutions in the embodiments of the present application will be clearly described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present application.

[0048] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are usually of the same type, and the number of objects is not limited. For example, the first object can be one or multiple. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally indicates an "or" relationship between the associated objects before and after.

[0049] Next, in conjunction with the accompanying drawings, through specific embodiments and their application scenarios, the grid connection point control method of a photovoltaic power station, the grid connection point control device of a photovoltaic power station, an electronic device, and a readable storage medium provided by the embodiments of the present application will be described in detail.

[0050] Among them, the grid connection point control method of a photovoltaic power station can be applied to a terminal, and specifically can be executed by hardware or software in the terminal.

[0051] In the following various embodiments, a terminal including a display and a touch-sensitive surface is described. However, it should be understood that the terminal may include one or more other physical user interface devices such as a physical keyboard, a mouse, and a joystick.

[0052] The grid connection point control method of a photovoltaic power station provided by the embodiments of the present application. The execution subject of the grid connection point control method of the photovoltaic power station can be an electronic device or a functional module or functional entity in the electronic device that can implement the grid connection point control method of the photovoltaic power station. The electronic devices mentioned in the embodiments of the present application include, but are not limited to, mobile phones, tablet computers, computers, cameras, and wearable devices, etc. Here, taking the electronic device as the execution subject, the grid connection point control method of the photovoltaic power station provided by the embodiments of the present application will be described.

[0053] As Figure 1 shown, the grid connection point control method of the photovoltaic power station includes: step 110, step 120, and step 130.

[0054] Step 110: Obtain the sampled electrical signals collected by each electric meter;

[0055] In this step, as Figure 5As shown in the figure, the photovoltaic power station includes at least one branch circuit. Each branch circuit is connected to the grid connection point and accesses the AC power grid through the grid connection point. An electric meter is respectively arranged on each branch circuit, and the electric meter is used to collect the sampled electrical signals of the set branch circuit.

[0056] Continue to refer to Figure 5 , each branch circuit is correspondingly connected with one or more devices. Among them, the devices can be power generation devices, energy storage devices or other types of devices, etc.; the number and types of devices set on different branch circuits can be the same or different; the types of devices set on the same branch circuit can be the same or different.

[0057] In some embodiments, a load can also be connected to the branch circuit.

[0058] In some embodiments, the electric meter is arranged between the transformer in the branch circuit and the load access point, and the transformer is arranged close to the grid connection point.

[0059] In some embodiments, the sampled electrical signals can include: active power and / or reactive power.

[0060] In this embodiment, according to the current actual operating conditions and control requirements of the photovoltaic power station, etc., active power or reactive power can be selectively collected. Of course, active power and reactive power can also be collected together. The sampled electrical signals are used to characterize the total active power and / or reactive power situation corresponding to this branch circuit at the current sampling moment.

[0061] In some embodiments, the sampled electrical signals can also be current or voltage, etc., and the active power and / or reactive power are obtained through conversion.

[0062] Step 120: Determine the target power corresponding to the target device according to the first sum of each sampled electrical signal, the first power reference value corresponding to the target branch in at least one branch circuit, and the first capacity of the target device among at least one device correspondingly connected to the target branch.

[0063] In this step, the target branch can be any branch circuit, and the target device can be any device among the devices connected to the target branch circuit. The control logics corresponding to the devices in each branch circuit are similar and can be independently controlled during the actual control process. Hereinafter, taking a device in one branch circuit as an example, the control logic will be described.

[0064] The first power reference value corresponding to the target branch is a control reference value used to balance the whole branch circuit. The first power reference value is an initial power reference value, including: the initial active power reference value corresponding to the target branch, and / or the initial reactive power reference value corresponding to the target branch, which can be obtained by statistical analysis of historical operating conditions; the target power is a control value used to balance the device.

[0065] The first capacity of the target device may be the rated capacity.

[0066] In some embodiments, the first power reference value corresponding to the target branch may be determined through the following steps:

[0067] It is determined according to the sum of the initial power reference values corresponding to the inverters on the target branch.

[0068] In this embodiment, the initial power reference values corresponding to the inverters may be summed to obtain the first power reference value.

[0069] The target power is the power reference value used to control the operation of a single device, including the target active power and / or the target reactive power. For different devices, the corresponding target power can be calculated.

[0070] In some embodiments, according to the category of the sampled electrical signal, a corresponding processing method may be selected to obtain the target power corresponding to the target device. In some embodiments, for the active power, the initial active power reference value corresponding to the target branch may be constrained according to the sampled electrical signals collected by each ammeter, and the target active power corresponding to the target device may be calculated based on the constrained power; for the reactive power, no constraint is required, and the target reactive power corresponding to the target device may be directly obtained based on the initial reactive power reference value corresponding to the target branch.

[0071] In some embodiments, step 120 may include:

[0072] In the case where the sampled electrical signal is active power, the first power reference value is constrained according to the first sum to obtain the second power reference value corresponding to the target branch;

[0073] Based on the first capacity of the target device, the second capacity corresponding to the target branch, and the second power reference value, the target power corresponding to the target device is obtained.

[0074] In this embodiment, the second capacity is used to represent the sum of the capacities of all the devices connected to the target branch. In the actual execution process, the second capacity may be determined according to the sum of the rated capacities of the devices provided on the corresponding branch.

[0075] The first sum is used to perform a range constraint on the first power reference value to make it within a reasonable range.

[0076] For the active power, the second power reference value is the first power reference value after upper and / or lower limit constraints. It can be understood that in the case where the first power reference value is respectively subjected to upper and lower limit constraints by the first sum, the second power reference value may include extreme values such as the minimum value and the maximum value.

[0077] Such as Figure 4As shown, taking the initial active power reference value corresponding to the target branch as the first power reference value as an example, in the actual execution process, the sampled electrical signals corresponding to the active power collected by each electricity meter are summed to obtain the electrical signal corresponding to the total active power after grid connection, that is, the first sum Ppcc; then, according to the first sum Ppcc, the initial active power reference value Pi_ref_init corresponding to the branch where a certain device is located is constrained to obtain the second power reference value Pi_ref corresponding to the branch; then, combining the first capacity of the device, the second capacity corresponding to the branch set by the device, and the second power reference value Pi_ref corresponding to the branch, the target active power Prefj corresponding to the device is calculated.

[0078] In some embodiments, a pre-trained network model can be used to predict the target power corresponding to the target device according to the first capacity of the target device, the second capacity corresponding to the target branch, and the first power reference value.

[0079] In some embodiments, constraining the first power reference value according to the first sum to obtain the second power reference value corresponding to the target branch may include:

[0080] Determine the first limit power corresponding to the grid connection point according to the first sum and the target constraint threshold;

[0081] Based on the second capacity corresponding to the target branch, the third capacity corresponding to the photovoltaic power station, and the first limit power, the first power reference value is constrained to obtain the second power reference value corresponding to the target branch.

[0082] In this embodiment, the target constraint threshold is the overall constraint threshold corresponding to the photovoltaic power station, which may include one or more constraint thresholds and is the threshold corresponding to the active power.

[0083] For the active power, the target constraint threshold may include: the upper constraint threshold Pref_up corresponding to the active power and / or the lower constraint threshold Pref_dn corresponding to the active power.

[0084] The first limit power is the total limit power corresponding to the photovoltaic power station. The first limit power may include: the upper limit power corresponding to the active power of the photovoltaic power station and the lower limit power corresponding to the photovoltaic power station. Among them, the upper limit power may be the output of the active power upper limit loop, and the lower limit power may be the output of the active power lower limit loop.

[0085] The third capacity is the sum of the second capacities corresponding to all branches included in the photovoltaic power station.

[0086] Taking the sampled electrical signal as the active power, and the target constraint threshold includes the upper constraint threshold Pref_up and the lower constraint threshold Pref_dn corresponding to the active power as an example, as Figure 3As shown, during the actual execution process, the difference is calculated between the sum Ppcc of the sampled electrical signals collected by the electricity meters set on each branch and the upper limit constraint threshold Pref_up, and the difference is PI-controlled to obtain the upper limit power Pup_out corresponding to the active power of the photovoltaic power station; the difference is calculated between the sum Ppcc of the sampled electrical signals collected by the electricity meters set on each branch and the lower limit constraint threshold Pref_dn, and the difference is PI-controlled to obtain the lower limit power Pdn_out corresponding to the active power of the photovoltaic power station.

[0087] Then, according to the ratio of the second capacity corresponding to the target branch to the third capacity corresponding to the photovoltaic power station, the weight corresponding to the target branch is determined. The first limit power is weighted according to the weight corresponding to the target branch, and the weighted value is used to constrain the first power reference value corresponding to the target branch to obtain the second active power reference value corresponding to the target branch.

[0088] In some embodiments, constraining the first power reference value based on the second capacity corresponding to the target branch, the third capacity corresponding to the photovoltaic power station, and the first limit power to obtain the second power reference value corresponding to the target branch may include:

[0089] Determining the second limit power corresponding to the target branch based on the product of the ratio of the second capacity to the third capacity and the first limit power;

[0090] Constraining the first power reference value based on the second limit power to obtain the second power reference value corresponding to the target branch.

[0091] In this embodiment, the second limit power is the limit power of the active power corresponding to the target branch, and the second limit power may include: the upper limit power corresponding to the active power of the target branch, and / or the lower limit power corresponding to the active power of the target branch.

[0092] The second limit power corresponding to the active power can be determined by the following formula:

[0093] Pi up_out =si·P up_out

[0094]

[0095] Where Pi up_out is the upper limit power corresponding to the active power of the i-th branch; si is the ratio of the second capacity to the third capacity of the i-th branch; P up_out is the upper limit power corresponding to the active power of the photovoltaic power station; S i is the second capacity of the i-th branch; S kis the second capacity of the k-th branch; k is a positive integer and k ≤ m; i, j, and m are all positive integers.

[0096] Pi dn_out = si·P dn_out

[0097]

[0098] where Pi dn_out is the lower limit power corresponding to the active power of the i-th branch; si is the ratio of the second capacity to the third capacity of the i-th branch; P dn_out is the lower limit power corresponding to the active power of the photovoltaic power station; S i is the second capacity of the i-th branch; S k is the second capacity of the k-th branch; k is a positive integer and k ≤ m; i, j, and m are all positive integers.

[0099] According to the grid connection point control method of the photovoltaic power station provided by the embodiments of the present application, by using the first sum to constrain the first power reference value, the upper and lower limit active powers of each branch can be respectively constrained, ensuring that each branch is within a reasonable range. On this basis, balanced control is performed on each device in each branch, thereby realizing precise grid connection point control; ensuring the normal power supply of the power station and improving the flexibility and stability of system control.

[0100] In some embodiments, step 120 may include:

[0101] When the sampled electrical signal is reactive power, the first power reference value is determined as the second power reference value;

[0102] Based on the first capacity of the target device, the second capacity of the target branch, and the second power reference value, the target power corresponding to the target device is obtained.

[0103] In this embodiment, continue to refer to Figure 4 , for reactive power, the initial reactive power reference value Qi_ref_init corresponding to the branch where a certain device is located can be directly used as the second power reference value Qi_ref of the branch; then, in combination with the first capacity of the device, the second capacity of the branch where the device is set, and the second power reference value Qi_ref of the branch, the target reactive power Qrefj corresponding to the device is calculated.

[0104] In some embodiments, the first power reference value corresponding to reactive power can be determined according to the following steps:

[0105] Based on the product of the ratio of the second capacity to the third capacity of the target branch and the initial reactive power of the photovoltaic power station, the first power reference value corresponding to the target branch is determined.

[0106] In this embodiment, the first power reference value corresponding to the reactive power can be obtained by performing a weighted calculation based on the initial reactive power corresponding to the photovoltaic power station.

[0107] The first power reference value corresponding to the reactive power can be determined by the following formula:

[0108] Qi ref = si·Q ref

[0109]

[0110] where Qi ref is the first power reference value corresponding to the reactive power of the i-th branch; si is the ratio of the second capacity to the third capacity of the i-th branch; Q ref is the initial value of the reactive power corresponding to the photovoltaic power station; S i is the second capacity of the i-th branch; S k is the second capacity of the k-th branch; k is a positive integer and k ≤ m; i, j, and m are all positive integers.

[0111] In some embodiments, obtaining the target power corresponding to the target device based on the first capacity of the target device, the second capacity corresponding to the target branch, and the second power reference value may include:

[0112] Determining the target power corresponding to the target device based on the product of the ratio of the first capacity to the second capacity and the second power reference value.

[0113] In this embodiment, by determining the weight of the target device according to the proportion of the first capacity of the target device in the total capacity of all devices of the branch where the target device is set, and performing a weighted process on the second power reference value corresponding to the branch where the target device is set according to this weight, the target power corresponding to the target device can be obtained.

[0114] For active power and reactive power, the calculation method of obtaining the target power corresponding to the target device based on the first capacity of the target device, the second capacity corresponding to the target branch, and the second power reference value is similar. The following takes active power and reactive power as examples for description.

[0115] When the sampled electrical signal is active power, the target active power can be calculated by the following formula:

[0116] P refj = sj·Pi ref

[0117]

[0118] where P refjis the target active power corresponding to the j-th device on the i-th branch; sj is the ratio of the first capacity of the j-th device to the second capacity of the i-th branch; Pi ref is the second active power reference value of the i-th branch; S f is the first capacity of the j-th device; S k is the first capacity of the k-th device; k is a positive integer and k ≤ n; i, j, and n are all positive integers.

[0119] In the case where the sampled electrical signal is reactive power, the target reactive power can be calculated through the following formula:

[0120] Q refj = sj·Qi ref

[0121]

[0122] where, Q refj is the target reactive power corresponding to the j-th device on the i-th branch; sj is the ratio of the first capacity of the j-th device to the second capacity of the i-th branch; Qi ref is the second reactive power reference value of the i-th branch; S j is the first capacity of the j-th device; S k is the first capacity of the k-th device; k is a positive integer and k ≤ n; i, j, and n are all positive integers.

[0123] According to the grid connection point control method of the photovoltaic power station provided by the embodiments of the present application, through the product of the ratio of the first capacity of the target device to the second capacity of the target branch and the second power reference value, the target power corresponding to the target device can be quickly calculated, so that the control power corresponding to each device in a complex grid connection circuit environment can be quickly and accurately calculated, realizing the power distribution of each branch of the power station, thereby realizing the overall grid connection point control, and ensuring the safe, stable, and efficient operation between the power station and the power grid.

[0124] Step 130: Control the target device based on the target power.

[0125] In this step, the target power is used as the reference power corresponding to the target device. After obtaining the target power corresponding to the target device, the operating state of the target device can be controlled according to this target power, including outputting active power or absorbing reactive power from the grid connection point, etc.

[0126] For any device set on any branch, the method such as from step 110 to step 130 can be used for independent control.

[0127] During the actual execution process, after calculating the target power, a PWM wave for driving the inverter switching tubes to work can be generated based on the target power to control the actual power of the inverter to track the target power.

[0128] In some embodiments, step 130 may include:

[0129] Control the target device based on the target power and the actual power of the target device.

[0130] In this embodiment, the actual output power includes the actual output power and / or the actual absorption power.

[0131] PI control can be performed according to the actual power and the target power of the target device to control the target device.

[0132] Of course, in other embodiments, other achievable control methods can also be adopted, which are not limited in this application.

[0133] The inventors found during the R & D process that in the related art, the grid connection point control is achieved by installing an electricity meter at the total grid connection point to obtain the electricity meter data. However, this method has problems such as a relatively high voltage level (10 KV or 35 KV) and large current at the grid connection point, which requires a high requirement for the electricity meter, resulting in a high cost; if the electricity meter is repaired and replaced, the entire power station needs to be powered off, which is difficult for installation and maintenance and affects the normal power supply demand; when the power station is expanded, the installed electricity meter may not support the new capacity, and a new electricity meter with a larger capacity needs to be replaced, further increasing the setting cost and the replacement difficulty, and the expandability of the circuit is poor;

[0134] In this application, by installing electricity meters on each branch, the voltage level and capacity of each branch are reduced, reducing the cost of the electricity meter; installing the electricity meter on the branch is simple, and during maintenance, only the corresponding branch needs to be disconnected, and other branches are not affected, and the entire power station can still continue to generate electricity, thus ensuring the normal power supply demand; on this basis, by installing electricity meters on the branch, while realizing the overall grid connection point control function, it is also possible to calculate the control power corresponding to each device in a complex grid connection circuit environment, realize the power distribution of each branch of the power station, and realize the branch power control function, improving the control flexibility and stability of the system.

[0135] According to the grid connection point control method of the photovoltaic power station provided by the embodiments of the present application, by setting electricity meters on each branch, precise control can be performed on each device according to the sampled electrical signals collected by the electricity meters on each branch, the first power reference value corresponding to each branch, and the first capacity of each device, so as to achieve precise grid connection point control; ensure the normal power supply of the power station, and improve the control flexibility and stability of the system.

[0136] The grid connection point control method for a photovoltaic power station provided by an embodiment of the present application may be executed by a grid connection point control device of the photovoltaic power station. In the embodiments of the present application, taking the grid connection point control device of the photovoltaic power station executing the grid connection point control method of the photovoltaic power station as an example, the grid connection point control device of the photovoltaic power station provided by the embodiments of the present application is described.

[0137] An embodiment of the present application also provides a grid connection point control device for a photovoltaic power station.

[0138] As Figure 12 shown, the photovoltaic power station includes at least one branch, each branch is correspondingly connected with at least one device, each branch is connected to the grid connection point, and an ammeter is arranged on each branch; the grid connection point control device of the photovoltaic power station includes: a first processing module 1210, a second processing module 1220, and a third processing module 1230.

[0139] The first processing module 1210 is configured to obtain the sampled electrical signals collected by each ammeter;

[0140] The second processing module 1220 is configured to determine the target power corresponding to the target device according to the first sum of each sampled electrical signal, the first power reference value corresponding to the target branch in at least one branch, and the first capacity of the target device among at least one device correspondingly connected to the target branch;

[0141] The third processing module 1230 is configured to control the target device based on the target power.

[0142] According to the grid connection point control device for a photovoltaic power station provided by an embodiment of the present application, by arranging ammeters on each branch, each device can be accurately controlled according to the sampled electrical signals collected by the ammeters on each branch, the first power reference value corresponding to each branch, and the first capacity of each device, so as to achieve accurate grid connection point control; ensure the normal power supply of the power station, and improve the flexibility and stability of system control.

[0143] In some embodiments, the second processing module 1220 may further be configured to:

[0144] Constrain the first power reference value according to the first sum to obtain the second power reference value corresponding to the target branch;

[0145] Based on the first capacity of the target device, the second capacity corresponding to the target branch, and the second power reference value, obtain the target power corresponding to the target device; wherein, the second capacity is the sum of the capacities of all devices correspondingly connected to the target branch.

[0146] In some embodiments, the second processing module 1220 may further be configured to:

[0147] Determine the target power corresponding to the target device based on the product of the ratio of the first capacity and the second capacity and the second power reference value.

[0148] In some embodiments, the second processing module 1220 may further be configured to:

[0149] Determine a first limit power corresponding to the grid connection point according to the first sum and the target constraint threshold;

[0150] Constrain the first power reference value based on the second capacity corresponding to the target branch, the third capacity corresponding to the photovoltaic power station, and the first limit power, to obtain a second power reference value corresponding to the target branch; wherein, the third capacity is the sum of the second capacities corresponding to each branch.

[0151] In some embodiments, the third processing module 1230 may further be configured to:

[0152] Control the target device based on the target power and the actual power of the target device.

[0153] In some embodiments, the apparatus may further include a fourth processing module, configured to:

[0154] Determine according to the sum of the initial power reference values corresponding to the inverters on the target branch.

[0155] The grid connection point control device of the photovoltaic power station in the embodiments of the present application may be an electronic device, or a component in an electronic device, such as an integrated circuit or a chip. The electronic device may be a terminal, or other devices other than the terminal. Exemplarily, the electronic device may be a mobile phone, a tablet computer, a laptop computer, a handheld computer, a vehicle-mounted electronic device, a Mobile Internet Device (MID), an augmented reality (AR) / virtual reality (VR) device, a robot, a wearable device, an ultra-mobile personal computer (UMPC), a netbook, or a personal digital assistant (PDA), etc., and may also be a server, a Network Attached Storage (NAS), a personal computer (PC), a television (TV), a teller machine, or a self-service machine, etc., which is not specifically limited in the embodiments of the present application.

[0156] The grid connection point control device of the photovoltaic power station in the embodiments of the present application may be a device with an operating system. The operating system may be an Android operating system, an IOS operating system, or other possible operating systems, which is not specifically limited in the embodiments of the present application.

[0157] The grid connection point control device of the photovoltaic power station provided by the embodiment of the present application can implement Figures 1 to 4 each process implemented by the method embodiment. To avoid repetition, it will not be elaborated here.

[0158] The embodiment of the present application also provides a photovoltaic power station.

[0159] As Figure 5 shown, the photovoltaic power station includes: at least one branch circuit, at least one electric meter, and a control module.

[0160] In this embodiment, at least one device is correspondingly connected to each branch circuit, and each branch circuit is connected to the grid connection point.

[0161] At least one electric meter is arranged corresponding to at least one branch circuit. The electric meter is arranged between the grid connection point and the access point of the device access branch circuit for collecting the sampled electrical signals corresponding to the branch circuit.

[0162] The connection method of the electric meter can be wired or wireless, including but not limited to: RS485 / WIFI / FE / SUB1G, etc.

[0163] The control module is electrically connected to each electric meter and is used to execute the grid connection point control method of the photovoltaic power station described in any of the above embodiments.

[0164] According to the photovoltaic power station provided by the embodiment of the present application, by arranging electric meters on each branch circuit, each device can be accurately controlled according to the sampled electrical signals collected by the electric meters of each branch circuit, the first power reference value corresponding to each branch circuit, and the first capacity of each device, so as to achieve accurate grid connection point control; ensure the normal power supply of the power station, and improve the flexibility and stability of system control.

[0165] In some embodiments, the control module may include: a power station controller.

[0166] In this embodiment, the power station controller is any one of the devices, or the power station controller is independent of each device.

[0167] As Figure 2 shown, the power station controller is used to obtain the sampled electrical signals collected by the electric meters of each branch circuit, the data of the power generation device or the energy storage device, calculate and allocate the target power corresponding to each device on each branch circuit, and realize the control of each branch circuit and the grid connection point of the power station.

[0168] In some embodiments, the control module may include: at least one sub-array controller.

[0169] In this embodiment, at least one sub-array controller is arranged corresponding to at least one branch circuit.

[0170] The sub-array controller is any device on the corresponding branch, or the sub-array controller is independent of each device.

[0171] The power station may include: a power station controller, sub-array controllers, and multiple power distribution branches. Each branch includes at least one of a power generation device, an energy storage device, and an electrical consumption device. When there is a power generation device or an energy storage device in the branch, there must be a sub-array controller (the sub-array controller can be an independent controller or the power generation device or the energy storage device itself), and the power station controller can be the power generation device or the energy storage device itself or an independent controller.

[0172] An ammeter needs to be installed on each branch. The ammeter can be connected to the power station controller, or can be connected to any power generation device or energy storage device in any branch, or can be connected to the sub-array controller.

[0173] It can be understood that the sub-array controller corresponding to a certain branch can be any device among the devices set on the branch, or can be a controller independent of the devices on the branch. The sub-array controller is electrically connected to the devices on the set branch. The power station controller can be any device among the devices in the photovoltaic power station, or can be a controller independent of the devices included in the photovoltaic power station.

[0174] Continue to refer to Figure 2 , the ammeter can be electrically connected to the sub-array controller corresponding to the set branch, for sending ammeter data to the sub-array controller, and the sub-array controller forwards the data to the power station controller; or it can also be directly electrically connected to the power station controller, for sending ammeter data to the power station controller.

[0175] Each sub-array controller can be electrically connected to the power station controller respectively, or can also be electrically connected in sequence according to the set positions, and the last sub-array controller is electrically connected to the power station controller.

[0176] Such as Figure 5 As shown, in some embodiments, the ammeter is electrically connected to the power generation device or the energy storage device, the sub-array controller is one of the power generation device or the energy storage device, the power station controller is one of the power generation device or the energy storage device, and the power generation device or the energy storage device obtains the ammeter data and sends it to the power station controller, and the power station controller aggregates the ammeter data of each branch. The power station controller obtains the ammeter data (active power, reactive power) of each branch, and calculates the power output of the power generation device or the energy storage device based on the data of the power generation device or the energy storage device (active, reactive, rated capacity, etc. information); m is greater than or equal to 2, and n is greater than or equal to 1.

[0177] Such as Figure 6As shown, in some embodiments, a power generation device or an energy storage device is connected to a sub-array controller, and an electricity meter is connected to the sub-array controller. The sub-array controller is an independent controller, and the power station controller is an independent controller. The sub-array controller obtains and sends the electricity meter data to the power station controller. The power station controller simultaneously obtains the electricity generation meter data (active power, reactive power) of each branch and the data of the power generation device or the energy storage device (information such as active power, reactive power, and rated capacity) to calculate the power output of the power generation device or the energy storage device.

[0178] As Figure 7 shown, in some embodiments, a power generation device or an energy storage device is connected to the power station controller, and the electricity meter is connected to the power station controller. The power station controller is an independent controller. The power station controller periodically obtains the electricity meter data (active power, reactive power) and the data of the power generation device or the energy storage device (information such as active power, reactive power, and rated capacity) to calculate the power output of the power generation device or the energy storage device.

[0179] As Figure 8 shown, in some embodiments, a power generation device or an energy storage device is connected to the power station controller, and the electricity meter is connected to the power generation device or the energy storage device. The power station controller is an independent controller. The power generation device or the energy storage device obtains the electricity meter data and sends it to the power station controller. The power station controller summarizes the electricity meter data of each branch. The power station controller obtains the electricity meter data (active power, reactive power) of each branch and the data of the power generation device or the energy storage device (information such as active power, reactive power, and rated capacity) to calculate the power output of the power generation device or the energy storage device.

[0180] As Figure 9 shown, in some embodiments, a power generation device or an energy storage device (the power generation or energy storage device supports other third-party devices) is connected to the sub-array controller, and the branch electricity meter is connected to the sub-array controller or the power station controller. The sub-array controller is an independent controller, and the power station controller is an independent controller. The sub-array controller periodically obtains and sends the electricity meter data. The power station controller simultaneously obtains the electricity meter data (active power, reactive power) of each branch and the data of the power generation device or the energy storage device (information such as active power, reactive power, and rated capacity) to calculate the power output of the power generation device or the energy storage device. The sub-array controller can communicate with the third-party power generation or energy storage device to obtain the third-party device information or control the third-party device. The power station controller can simultaneously monitor the load power consumption data through the electricity meter.

[0181] As Figure 10As shown, in some embodiments, a power generation device or an energy storage device (the power generation or energy storage device supports other third-party devices) is connected to a power station controller, the power station controller is an independent controller, a branch circuit meter is connected to the power generation device or the energy storage device or the power station controller, the power generation device or the energy storage device periodically obtains and sends meter data, the power station controller periodically obtains meter data (active power, reactive power), and calculates the power output of the power generation device or the energy storage device based on the data of the power generation device or the energy storage device (such as active power, reactive power, rated capacity, etc.). The power station controller can communicate with the third-party power generation or energy storage device to obtain third-party device information or control third-party devices, and at the same time, the power station controller can monitor the power consumption data of the load branch through the meter.

[0182] As Figure 11 As shown, in some embodiments, a power generation device or an energy storage device (the power generation or energy storage device supports other third-party devices) is connected to a power station controller, the power station controller is an independent controller, a branch circuit meter is connected to the power station controller, the power station controller periodically obtains meter data (active power, reactive power), and calculates the power output of the power generation device or the energy storage device based on the data of the power generation device or the energy storage device (such as active power, reactive power, rated capacity, etc.). The power station controller can communicate with the third-party power generation or energy storage device to obtain third-party device information or control third-party devices, and at the same time, the power station controller can monitor the power consumption data of the load branch through the meter.

[0183] In some embodiments, as Figure 13 As shown, an embodiment of the present application further provides an electronic device 1300, including a processor 1301, a memory 1302, and a computer program stored on the memory 1302 and executable on the processor 1301. When the program is executed by the processor 1301, it implements each process of the above-mentioned embodiment of the grid connection point control method of the photovoltaic power station, and can achieve the same technical effect. To avoid repetition, it will not be elaborated here.

[0184] It should be noted that the electronic devices in the embodiments of the present application include the above-mentioned mobile electronic devices and non-mobile electronic devices.

[0185] An embodiment of the present application further provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements each process of the above-mentioned embodiment of the grid connection point control method of the photovoltaic power station, and can achieve the same technical effect. To avoid repetition, it will not be elaborated here.

[0186] Wherein, the processor is the processor in the electronic device described in the above embodiment. The readable storage medium includes computer-readable storage media, such as computer read-only memory ROM, random access memory RAM, magnetic disk or optical disk, etc.

[0187] An embodiment of the present application further provides a computer program product, including a computer program, which, when executed by a processor, implements the grid connection point control method of the above photovoltaic power station.

[0188] Wherein, the processor is the processor in the electronic device described in the above embodiment. The readable storage medium includes computer-readable storage media such as computer read-only memory ROM, random access memory RAM, magnetic disk or optical disc, etc.

[0189] Another embodiment of the present application provides a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement each process of the grid connection point control method embodiment of the above photovoltaic power station, and can achieve the same technical effect. To avoid repetition, it will not be elaborated here.

[0190] It should be understood that the chip mentioned in the embodiment of the present application can also be called a system-on-chip, system chip, chip system or system-on-chip, etc.

[0191] It should be noted that in this article, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including that element. In addition, it should be pointed out that the methods and devices in the embodiments of the present application are not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in a reverse order according to the functions involved. For example, the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0192] Through the description of the above embodiments, those skilled in the art can clearly understand that the method of the above embodiments can be implemented by means of software plus a necessary general hardware platform. Of course, it can also be implemented by hardware, but in many cases the former is a better implementation. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, can be embodied in the form of a computer software product. The computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disc), and includes several instructions for causing a terminal (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in various embodiments of the present application.

[0193] The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present application, those of ordinary skill in the art can also make many forms without departing from the purpose of the present application and the scope protected by the claims, and all of them belong to the protection scope of the present application.

[0194] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0195] Although the embodiments of the present application have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and purposes of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for controlling a grid connection point of a photovoltaic power station, characterized in that: The photovoltaic power station comprises at least one branch, each branch is connected to at least one device, each branch is connected to a grid connection point, and each branch is provided with an electric meter; the method comprises: Acquiring sampled electrical signals collected by each of the electric meters; Determine a target power corresponding to the target device according to a first sum of the sampled electrical signals, a first power reference value corresponding to a target branch in the at least one branch, and a first capacity of a target device in at least one device connected to the target branch; Based on the target power, the target device is controlled.

2. The method for controlling the grid connection point of a photovoltaic power station according to claim 1, characterized in that: The determining the target power corresponding to the target device according to the first sum of the sampled electrical signals, the first power reference value corresponding to the target branch in the at least one branch, and the first capacity of the target device in at least one device connected to the target branch includes: Constraining the first power reference value according to the first sum to obtain a second power reference value corresponding to the target branch; Based on the first capacity of the target device, the second capacity corresponding to the target branch and the second power reference value, the target power corresponding to the target device is obtained; wherein the second capacity is the sum of the capacities of all devices connected to the target branch.

3. The grid connection point control method of a photovoltaic power station according to claim 2, characterized in that: The obtaining, based on the first capacity of the target device, the second capacity corresponding to the target branch, and the second power reference value, a target power corresponding to the target device, includes: The target power corresponding to the target device is determined based on a ratio of the first capacity to the second capacity multiplied by the second power reference value.

4. The method for controlling the grid connection point of a photovoltaic power station according to claim 2, characterized in that: The constraining the first power reference value according to the first sum to obtain a second power reference value corresponding to the target branch includes: Determining a first limited power corresponding to the grid connection point according to the first sum and a target constraint threshold; The first power reference value is constrained based on the second capacity corresponding to the target branch, the third capacity corresponding to the photovoltaic power station and the first limited power to obtain the second power reference value corresponding to the target branch; wherein the third capacity is the sum of the second capacities corresponding to each of the branches.

5. The method for controlling the grid connection point of a photovoltaic power station according to any one of claims 1 to 4, characterized in that: The controlling the target device based on the target power includes: The target device is controlled based on the target power and an actual power of the target device.

6. The method for controlling the grid connection point of a photovoltaic power station according to any one of claims 1 to 4, characterized in that: The sampled electrical signal includes active power and / or reactive power.

7. The method for controlling the grid connection point of a photovoltaic power station according to any one of claims 1 to 4, characterized in that: The first power reference value corresponding to the target branch is determined by the following steps: The power consumption of the inverter is determined according to the sum of the initial power reference values ​​corresponding to each inverter on the target branch.

8. A photovoltaic power station grid connection point control device, characterized in that: The photovoltaic power station comprises at least one branch, each branch is connected to at least one device, each branch is connected to a grid connection point, and each branch is provided with an electric meter; the device comprises: A first processing module, used for acquiring the sampled electrical signals collected by each of the electric meters; A second processing module, configured to determine a target power corresponding to the target device according to a first sum of the sampled electrical signals, a first power reference value corresponding to a target branch in the at least one branch, and a first capacity of a target device in at least one device connected to the target branch; The third processing module is used to control the target device based on the target power.

9. A photovoltaic power station, characterized in that: include: At least one branch, each branch is connected to at least one device, and each branch is connected to a grid connection point; At least one electric meter is arranged in one-to-one correspondence with the at least one branch, and the electric meter is arranged between the grid connection point and the access point where the device is connected to the branch, and is used to collect a sampled electric signal corresponding to the branch; A control module, the control module is electrically connected to each of the electric meters, and is used to execute the grid connection point control method of the photovoltaic power station as described in any one of claims 1 to 7.

10. The photovoltaic power station according to claim 9, characterized in that: The control module includes: a power station controller, which is any one of the devices, or the power station controller is independent of the devices.

11. The photovoltaic power station according to claim 9 or 10, characterized in that: The control module further includes: At least one sub-array controller, the at least one sub-array controller is arranged in one-to-one correspondence with the at least one branch; the sub-array controller is any device on the corresponding branch, or the sub-array controller is independent of each of the devices.

12. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the grid connection point control method of a photovoltaic power station as described in any one of claims 1 to 7 is implemented.

13. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the grid connection point control method of the photovoltaic power station as claimed in any one of claims 1 to 7 is implemented.

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