A photovoltaic field control method, device and system under power curtailment conditions

Abstract

This invention discloses a photovoltaic (PV) field control method under power curtailment conditions. By calculating the active power command deviation, the deviation between the currently acquired dispatch command and the active power command of each inverter can be calculated. Then, the active power command deviation is allocated based on the ratio of the actual real-time active power output of each inverter to the dispatch command, resulting in an allocation coefficient for each inverter. This allows for real-time adjustment of the inverter's output power based on the current actual output value and the dispatch command, thus achieving precise allocation of dispatch commands to each inverter. This invention also provides a PV field control device and a PV field control system under power curtailment conditions, which also possess the aforementioned beneficial effects.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic power plant control technology, and in particular to a photovoltaic field control method, a photovoltaic field control device, and a photovoltaic field control system under power curtailment conditions. Background Technology

[0002] Currently, automatic generation control plays a role in maintaining the reception and distribution of dispatch instructions for photovoltaic power plants. How to efficiently distribute dispatch instructions to multiple photovoltaic inverter groups is a practical problem currently faced in photovoltaic power plant research.

[0003] Existing automatic generation control systems can accurately transmit dispatch commands to the inverter arrays of photovoltaic (PV) power plants. However, because PV power plants are equipped with inverters from multiple brands, the adjustment and control response times of different inverters vary, leading to inconsistent responses when directly allocating active power commands. Furthermore, the significant differences in adjustment precision among different inverters result in variations in the actual output of the PV panels. Particularly when PV power plants face power curtailment conditions, the inverters cannot operate in maximum power point tracking (MPPT) mode, making rational active power allocation even more difficult. Therefore, providing a PV power plant control method that can accurately allocate dispatch commands to each inverter is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a photovoltaic field control method under power curtailment conditions, which can accurately allocate scheduling instructions to each inverter; this invention also provides a photovoltaic field control device and a photovoltaic field control system under power curtailment conditions, which can accurately allocate scheduling instructions to each inverter.

[0005] To address the aforementioned technical problems, this invention provides a photovoltaic field control method under power curtailment conditions, comprising:

[0006] Obtain scheduling instructions, as well as the active power instructions corresponding to each of the multiple inverters;

[0007] Calculate the active power instruction deviation based on the scheduling instruction and multiple active power instructions;

[0008] Based on the real-time active power value of each inverter, the active power command and the scheduling command calculate the allocation coefficient corresponding to each inverter; the allocation coefficient represents the ratio of the real-time active power value of each inverter to the scheduling command.

[0009] The total station deviation allocation for each inverter is calculated based on the allocation coefficient and the active power command deviation.

[0010] The total station deviation allocation is sent to the corresponding inverter so that the inverter outputs electrical energy according to the total station deviation allocation.

[0011] Optionally, calculating the active power instruction deviation based on the scheduling instruction and the plurality of active power instructions includes:

[0012] The active power instruction deviation is obtained by subtracting each active power instruction from the scheduling instruction.

[0013] Optionally, the step of the inverter distributing output power according to the main station deviation includes:

[0014] The inverter acquires the corresponding main station deviation allocation, the real-time active power value, and the previous active power command;

[0015] The active power control deviation is calculated based on the central station deviation allocation, the real-time active power value, and the previous active power command.

[0016] Calculate the proportional parameter instruction based on the active power control deviation and proportional conversion coefficient;

[0017] Calculate the integral parameter instruction based on the active power control deviation and integral conversion coefficient;

[0018] The differential parameter command is calculated based on the active power control deviation and the differential conversion coefficient.

[0019] The current active power command is calculated based on the proportional parameter command, the integral parameter command, the derivative parameter command, and the active power control deviation.

[0020] The corresponding electrical energy is output according to the current active power command.

[0021] Optionally, the step of calculating the active power control deviation based on the main station deviation allocation, the real-time active power value, and the previous active power command includes:

[0022] The active power control deviation is obtained by adding the previous active power command to the real-time active power value and then subtracting the central station deviation allocation.

[0023] Optionally, the instruction to calculate the proportional parameter based on the active power control deviation and the proportional conversion coefficient includes:

[0024] The absolute value of the active power control deviation is multiplied by the proportional conversion coefficient to obtain the proportional parameter command.

[0025] The instruction to calculate the integral parameters based on the active power control deviation and the integral conversion coefficient includes:

[0026] The integral parameter command is obtained by multiplying the absolute value of the active power control deviation by the reciprocal of the integral conversion coefficient.

[0027] The instruction to calculate the differential parameter based on the active power control deviation and the differential conversion coefficient includes:

[0028] The differential parameter command is obtained by multiplying the absolute value of the active control deviation by the differential conversion coefficient.

[0029] Optionally, the step of calculating the current active power command based on the proportional parameter command, the integral parameter command, the derivative parameter command, and the active power control deviation includes:

[0030] The proportional parameter command, the integral parameter command, and the derivative parameter command are each multiplied by the active power control deviation and then added together to obtain the current active power command.

[0031] The present invention also provides a photovoltaic field control device under power curtailment conditions, comprising:

[0032] The substation acquisition module is used to acquire scheduling instructions and active power instructions corresponding to each of the multiple inverters.

[0033] The active power instruction deviation module is used to calculate the active power instruction deviation based on the scheduling instruction and multiple active power instructions.

[0034] The allocation coefficient module is used to calculate the allocation coefficient corresponding to each inverter based on the real-time active power value of each inverter, the active power instruction, and the scheduling instruction.

[0035] The main station deviation allocation module is used to calculate the main station deviation allocation of each inverter based on the allocation coefficient and the active power command deviation.

[0036] The power output module is used to send the total station deviation allocation to the corresponding inverter, so that the inverter outputs power according to the total station deviation allocation.

[0037] Optional, also includes:

[0038] The inverter acquisition module is used for the inverter to acquire the corresponding main station deviation allocation, the active power real-time value, and the previous active power command;

[0039] The active power control deviation module is used to calculate the active power control deviation based on the main station deviation allocation, the real-time active power value, and the previous active power command.

[0040] The proportional parameter instruction module is used to calculate the proportional parameter instruction based on the active power control deviation and the proportional conversion coefficient.

[0041] The integral parameter instruction module is used to calculate the integral parameter instruction based on the active power control deviation and the integral conversion coefficient.

[0042] The differential parameter instruction module is used to calculate the differential parameter instruction based on the active power control deviation and the differential conversion coefficient.

[0043] The active power instruction module is used to calculate the current active power instruction based on the proportional parameter instruction, the integral parameter instruction, the derivative parameter instruction, and the active power control deviation.

[0044] The inverter power output module is used to output corresponding power according to the current active power command.

[0045] The present invention also provides a photovoltaic field control system under power curtailment conditions, including a control substation and multiple inverters, each of which is connected to a photovoltaic cell;

[0046] The control substation is used for:

[0047] Obtain scheduling instructions, as well as the active power instructions corresponding to each of the multiple inverters;

[0048] Calculate the active power instruction deviation based on the scheduling instruction and multiple active power instructions;

[0049] Based on the real-time active power value of each inverter, the active power command and the scheduling command calculate the allocation coefficient corresponding to each inverter.

[0050] The total station deviation allocation for each inverter is calculated based on the allocation coefficient and the active power command deviation.

[0051] The total station deviation allocation is sent to the corresponding inverter so that the inverter outputs electrical energy according to the total station deviation allocation.

[0052] Optionally, the inverter is specifically used for:

[0053] Obtain the corresponding main station deviation allocation, the real-time active power value, and the previous active power command;

[0054] The active power control deviation is calculated based on the central station deviation allocation, the real-time active power value, and the previous active power command.

[0055] Calculate the proportional parameter instruction based on the active power control deviation and proportional conversion coefficient;

[0056] Calculate the integral parameter instruction based on the active power control deviation and integral conversion coefficient;

[0057] The differential parameter command is calculated based on the active power control deviation and the differential conversion coefficient.

[0058] The current active power command is calculated based on the proportional parameter command, the integral parameter command, the derivative parameter command, and the active power control deviation.

[0059] The corresponding electrical energy is output according to the current active power command.

[0060] The present invention provides a photovoltaic field control method under power curtailment conditions, comprising: acquiring a dispatch command and active power commands corresponding to multiple inverters; calculating active power command deviation based on the dispatch command and the multiple active power commands; calculating the allocation coefficient corresponding to each inverter based on the real-time active power value of each inverter, the active power command, and the dispatch command; the allocation coefficient characterizes the ratio of the real-time active power value of each inverter to the dispatch command; calculating the total station deviation allocation for each inverter based on the allocation coefficient and the active power command deviation; and sending the total station deviation allocation to the corresponding inverter so that the inverter outputs electrical energy according to the total station deviation allocation.

[0061] By calculating the active power command deviation, the deviation between the currently acquired dispatch command and the active power command of each inverter can be calculated. Then, the active power command deviation is allocated according to the ratio of the actual real-time active power output of each inverter to the dispatch command, and the allocation coefficient of each inverter is obtained. Thus, the output power of the inverter can be adjusted in real time according to the current actual output value of each inverter and the dispatch command, thereby achieving precise allocation of dispatch commands to each inverter.

[0062] The present invention also provides a photovoltaic field control device and a photovoltaic field control system under power curtailment conditions, which have the same beneficial effects as described above, and will not be elaborated further here. Attached Figure Description

[0063] To more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0064] Figure 1 A flowchart illustrating a photovoltaic field control method under power curtailment conditions provided in an embodiment of the present invention;

[0065] Figure 2 Flowchart for the empty box control substation;

[0066] Figure 3 A flowchart illustrating a specific photovoltaic field control method under power curtailment conditions provided in an embodiment of the present invention;

[0067] Figure 4 Flowchart of an empty inverter box;

[0068] Figure 5This is a structural block diagram of a photovoltaic field control device under power-limited conditions provided in an embodiment of the present invention;

[0069] Figure 6 This is a structural block diagram of a photovoltaic field control system under power-limited conditions provided in an embodiment of the present invention. Detailed Implementation

[0070] The core of this invention is to provide a photovoltaic (PV) field control method under power curtailment conditions. In existing technologies, PV power plants are equipped with inverters from multiple brands, and the adjustment and control response times of different inverters vary, leading to inconsistent responses to direct active power allocation commands. Furthermore, the varying adjustment precision of different inverters results in differences in the actual output of the PV panels. Particularly when PV power plants face power curtailment conditions, the PV inverters cannot operate in maximum power point tracking (MPPT) mode, making rational active power allocation even more difficult.

[0071] The photovoltaic field control method under power curtailment conditions provided by this invention includes: acquiring dispatch instructions and active power instructions corresponding to each of multiple inverters; calculating active power instruction deviation based on the dispatch instructions and multiple active power instructions; calculating the allocation coefficient corresponding to each inverter based on the real-time active power value of each inverter, the active power instructions, and the dispatch instructions; the allocation coefficient characterizes the ratio of the real-time active power value of each inverter to the dispatch instructions; calculating the total station deviation allocation for each inverter based on the allocation coefficient and the active power instruction deviation; and sending the total station deviation allocation to the corresponding inverter so that the inverter outputs electrical energy according to the total station deviation allocation.

[0072] By calculating the active power command deviation, the deviation between the currently acquired dispatch command and the active power command of each inverter can be calculated. Then, the active power command deviation is allocated according to the ratio of the actual real-time active power output of each inverter to the dispatch command, and the allocation coefficient of each inverter is obtained. Thus, the output power of the inverter can be adjusted in real time according to the current actual output value of each inverter and the dispatch command, thereby achieving precise allocation of dispatch commands to each inverter.

[0073] To enable those skilled in the art to better understand the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0074] Please refer to Figure 1 as well as Figure 2 , Figure 1A flowchart illustrating a photovoltaic field control method under power curtailment conditions provided in an embodiment of the present invention; Figure 2 Flowchart for the empty box controlling the substation.

[0075] First, it should be noted that in this embodiment of the invention, the photovoltaic field control method is mainly applied to the control substation. In practice, each photovoltaic cell needs to be connected to an inverter, and the entire photovoltaic power plant typically requires multiple inverters. The aforementioned control substation is connected to multiple inverters, and this control substation is used to realize the automatic control of multiple inverters.

[0076] See Figure 1 as well as Figure 2 In this embodiment of the invention, the photovoltaic field control method under power curtailment conditions includes:

[0077] S101: Obtain scheduling instructions and active power instructions corresponding to each of the multiple inverters.

[0078] This dispatch instruction is specifically issued by the grid company's dispatch personnel and is primarily used to maintain the overall stability of the power grid. Since grid-connected photovoltaic systems must unconditionally accept dispatch control, the dispatcher can adjust the power station in real time based on grid stability and weather conditions. In this step, the control substation first receives the dispatch instruction, as well as the active power instructions corresponding to each of the multiple inverters connected to the control substation.

[0079] The aforementioned active power command is typically generated by the inverter's own control module when controlling the inverter's output power. This active power command is generated by the inverter and also acts on the inverter to adjust its output power. For the specific physical meaning of the active power command, please refer to existing technologies; it will not be elaborated upon here.

[0080] S102: Calculate the active power instruction deviation based on the scheduling instructions and multiple active power instructions.

[0081] In this step, the active power command deviation is calculated based on the scheduling command and active power command obtained in S103. This active power command deviation corresponds to the multiple inverters connected to the control substation; that is, this step needs to calculate the overall deviation of the control substation corresponding to the scheduling command. Specifically, the active power command deviation is equal to the scheduling command minus the sum of all active power commands, i.e., active power command deviation = P ord -sum(P i ), i = 1, 2, ..., n; where P ord For scheduling instructions, P i Let be the active power command for the i-th inverter, and sum be the summation symbol. Specifically, this step typically involves subtracting each active power command from the scheduling command to obtain the active power command deviation, thereby achieving real-time tracking of the scheduling command.

[0082] S103: Calculate the allocation coefficient for each inverter based on the real-time active power value, active power command, and scheduling command of each inverter.

[0083] In this embodiment of the invention, the allocation coefficient represents the ratio of the real-time active power value of each inverter to the scheduling command. Specifically, the specific calculation formula for this allocation coefficient in this embodiment of the invention is as follows:

[0084]

[0085] Where L i P is the allocation coefficient corresponding to the i-th inverter. mi This represents the real-time active power value of the i-th inverter. In the above formula, sign is the sign function; when the value inside the parentheses is greater than 0, sign outputs 1; when the value inside the parentheses is less than 0, sign outputs 0.

[0086] S104: Calculate the total station deviation allocation for each inverter based on the allocation coefficient and the active power command deviation.

[0087] In this step, the allocation coefficients calculated in S103 and the active power command deviation calculated in S102 are used to calculate the total station deviation allocation to be sent to each inverter. Specifically, the active power command deviation is allocated according to the ratio of the active power Pmi sent by each inverter to the dispatch command Pord, that is, the active power command deviation is allocated to the L corresponding to the i-th inverter. i Multiplying these together yields the total station deviation allocation P corresponding to the i-th inverter. ierr By repeating the above process, the corresponding master station deviation allocation can be assigned to multiple inverters.

[0088] S105: Send the main station deviation allocation to the corresponding inverter so that the inverter can output electrical energy according to the main station deviation allocation.

[0089] In this step, the control substation sends the total station deviation allocation calculated in S104 to the corresponding inverter, so that the inverter can adjust the total station deviation allocation P according to the obtained data. ierr The inverter outputs the corresponding electrical energy. The specific process of distributing the output electrical energy according to the deviation of the main station will be described in detail in the following embodiments of the invention, and will not be repeated here.

[0090] The present invention provides a photovoltaic field control method under power curtailment conditions, comprising: acquiring a dispatch command and active power commands corresponding to multiple inverters; calculating active power command deviation based on the dispatch command and the multiple active power commands; calculating the allocation coefficient corresponding to each inverter based on the real-time active power value of each inverter, the active power command, and the dispatch command; the allocation coefficient characterizes the ratio of the real-time active power value of each inverter to the dispatch command; calculating the total station deviation allocation for each inverter based on the allocation coefficient and the active power command deviation; and sending the total station deviation allocation to the corresponding inverter so that the inverter outputs electrical energy according to the total station deviation allocation.

[0091] By calculating the active power command deviation, the deviation between the currently acquired dispatch command and the active power command of each inverter can be calculated. Then, the active power command deviation is allocated according to the ratio of the actual real-time active power output of each inverter to the dispatch command, and the allocation coefficient of each inverter is obtained. Thus, the output power of the inverter can be adjusted in real time according to the current actual output value of each inverter and the dispatch command, thereby achieving precise allocation of dispatch commands to each inverter.

[0092] The specific details of the photovoltaic field control method under power-limited conditions provided by this invention will be described in detail in the following embodiments.

[0093] Please refer to Figure 3 as well as Figure 4 , Figure 3 A flowchart illustrating a specific photovoltaic field control method under power curtailment conditions provided in an embodiment of the present invention; Figure 4 This is a flowchart of the empty box for an inverter.

[0094] It should be noted that the control method provided in this embodiment of the invention is mainly applied to inverters, specifically the adaptive output power flow of the inverter after receiving the main station deviation allocation. That is, this embodiment of the invention specifically describes the specific steps in S105 above, where the inverter allocates output power according to the main station deviation. The specific workflow of the control substation has been described in detail in the above embodiments of the invention and will not be repeated here.

[0095] See Figure 3 as well as Figure 4 In this embodiment of the invention, the photovoltaic field control method under power curtailment conditions includes:

[0096] S201: The inverter obtains the corresponding main station deviation allocation, active real-time value, and previous active instructions.

[0097] In this step, the inverter's control module will specifically receive the aforementioned central station deviation allocation P. ierr The inverter's own real-time active power value, i.e., the inverter's own active power output P. miAnd the active power command P generated before the inverter i This refers to the active power instructions generated before the current scheduling instruction takes effect.

[0098] S202: Calculate the active power control deviation based on the main station deviation allocation, real-time active power value, and previous active power commands.

[0099] In this step, the inverter needs to calculate the deviation of the corresponding scheduling command for each inverter. Specifically, this step typically involves adding the real-time active power value to the previous active power command, and then subtracting the central station deviation allocation to obtain the active power control deviation. That is, the above active power control deviation = P mi +P i -P ierr .

[0100] S203: Instruction to calculate proportional parameters based on active power control deviation and proportional conversion coefficient.

[0101] In this embodiment of the invention, a proportional conversion coefficient Ki is preset. Then, in this step, the inverter can specifically multiply the absolute value of the active power control deviation by the proportional conversion coefficient to obtain the proportional parameter command. The absolute value of the active power control deviation can be calculated in this step using the abs (absolute) module. After using the abs module, the absolute value of the active power control deviation is multiplied by the proportional conversion coefficient to obtain the proportional parameter command. The proportional parameter command is then typically input into the proportional limiting module, i.e., the proportional limiting module is used to control the proportional parameter command within a reasonable range.

[0102] S204: Instruction to calculate integral parameters based on active power control deviation and integral conversion coefficient.

[0103] In this embodiment of the invention, an integral conversion coefficient Ti is preset. Then, in this step, the inverter can specifically multiply the absolute value of the active power control deviation by the reciprocal of the integral conversion coefficient to obtain the integral parameter command. The absolute value of the active power control deviation is typically calculated using the abs module in this step. After using the abs module, the absolute value of the active power control deviation is multiplied by the reciprocal of the integral conversion coefficient, i.e., 1 / Ti, thereby converting the active power control deviation into an integral parameter command. The result of multiplying the active power control deviation by 1 / Ti is then input into the integral function 1 / s, where s represents the Laplace operator in automatic control theory, and 1 / s represents the integral function. Typically, the integral parameter command also needs to be input into the integral limiting module, i.e., the integral limiting module is used to control the integral parameter command within a reasonable range.

[0104] S205: Instruction to calculate differential parameters based on active control deviation and differential conversion coefficient.

[0105] In this embodiment of the invention, a differential conversion coefficient Di is preset. Then, in this step, the inverter can specifically multiply the absolute value of the active power control deviation by the differential conversion coefficient to obtain the differential parameter command. The absolute value of the active power control deviation is typically calculated using the abs module in this step. After using the abs module, the absolute value of the active power control deviation is multiplied by the differential conversion coefficient Di to obtain the differential parameter command. Subsequently, the proportional parameter command is typically input into the integral limiting module, i.e., the integral limiting module is used to control the differential parameter command within a reasonable range.

[0106] S206: Calculate the current active power command based on the proportional parameter command, integral parameter command, derivative parameter command, and the active power control deviation.

[0107] The current active power command is the active power command generated by the inverter based on the latest dispatch command. At this time, the inverter has not yet output electrical energy according to the current active power command. Specifically, in this step, the proportional parameter command, the integral parameter command, and the derivative parameter command are each multiplied by the active power control deviation and then added together to obtain the current active power command.

[0108] In this step, the inverter typically uses a multiplier to multiply the proportional parameter command by the active power control deviation to obtain the proportional output. Simultaneously, it first uses a multiplier to multiply the differential parameter command by the active power control deviation, and then inputs the result into a differential tracker to obtain the differential output. The differential tracker can output two signals, z1(t) and z2(t), based on an input signal v(t). z1(t) tracks signal v(t), and z2(t) is the derivative of z1(t). In this case, z2(t) can be considered an approximate derivative of v(t). First, the differential parameter command is multiplied by the active power control deviation using a multiplier, and then the differential output corresponding to the differential parameter command is obtained using the differential tracker.

[0109] Simultaneously, in this step, the integral parameter command output by the integral function 1 / s and the active power control deviation are input into the divider to obtain the integral output. Finally, in this step, the proportional output, integral output, and derivative output are summed, and then the active power limit is input to restrict the output range, ultimately calculating the active power command of the inverter.

[0110] S207: Output the corresponding electrical energy according to the current active power command.

[0111] Finally, in this step, the inverter will output the corresponding electrical energy according to the active power command calculated in S206 to complete the dispatch command.

[0112] The photovoltaic field control method under power curtailment conditions provided by this invention can adaptively adjust the active power command of the inverter in real time, making the active power distribution of the inverter more uniform and improving the utilization efficiency of each inverter.

[0113] The following is an introduction to a photovoltaic field control device under power curtailment conditions provided by an embodiment of the present invention. The photovoltaic field control device described below can be referred to in correspondence with the photovoltaic field control method described above.

[0114] Please refer to Figure 5 , Figure 5 This is a structural block diagram of a photovoltaic field control device under power-limited conditions provided in an embodiment of the present invention.

[0115] Reference Figure 5 In this embodiment of the invention, the photovoltaic field control device may include:

[0116] The substation acquisition module 100 is used to acquire scheduling instructions and the active power instructions corresponding to each of the multiple inverters.

[0117] The active power instruction deviation module 200 is used to calculate the active power instruction deviation based on the scheduling instruction and multiple active power instructions.

[0118] The allocation coefficient module 300 is used to calculate the allocation coefficient corresponding to each inverter based on the real-time active power value of each inverter, the active power instruction, and the scheduling instruction.

[0119] The main station deviation allocation module 400 is used to calculate the main station deviation allocation of each inverter based on the allocation coefficient and the active power command deviation.

[0120] The power output module 500 is used to send the total station deviation allocation to the corresponding inverter so that the inverter outputs power according to the total station deviation allocation.

[0121] It should be noted that the aforementioned substation acquisition module 100, active power instruction deviation module 200, allocation coefficient module 300, main station deviation allocation module 400, and power output module 500 are usually located in the control substation. The specific contents of the control substation have been described in detail in the above embodiments of the invention, and will not be repeated here.

[0122] Preferably, in this embodiment of the invention, the active power instruction deviation module 200 is specifically used for:

[0123] The active power instruction deviation is obtained by subtracting each active power instruction from the scheduling instruction.

[0124] Preferably, in this embodiment of the invention, it further includes:

[0125] The inverter acquisition module is used for the inverter to acquire the corresponding main station deviation allocation, the real-time active power value, and the previous active power command.

[0126] The active power control deviation module is used to calculate the active power control deviation based on the main station deviation allocation, the real-time active power value, and the previous active power command.

[0127] The proportional parameter instruction module is used to calculate the proportional parameter instruction based on the active power control deviation and the proportional conversion coefficient.

[0128] The integral parameter instruction module is used to calculate integral parameter instructions based on the active power control deviation and the integral conversion coefficient.

[0129] The differential parameter instruction module is used to calculate differential parameter instructions based on the active power control deviation and the differential conversion coefficient.

[0130] The active power instruction module is used to calculate the current active power instruction based on the proportional parameter instruction, the integral parameter instruction, the derivative parameter instruction, and the active power control deviation.

[0131] The inverter power output module is used to output corresponding power according to the current active power command.

[0132] It should be noted that the inverter acquisition module, active power control deviation module, proportional parameter instruction module, integral parameter instruction module, derivative parameter instruction module, active power instruction module, and inverter power output module mentioned above are usually set in the inverter, specifically in the control module of the inverter. The specific contents of the inverter have been described in detail in the above invention embodiments, and will not be repeated here.

[0133] Preferably, in this embodiment of the invention, the active power control deviation module is specifically used for:

[0134] The active power control deviation is obtained by adding the previous active power command to the real-time active power value and then subtracting the central station deviation allocation.

[0135] Preferably, in this embodiment of the invention, the proportional parameter instruction module is specifically used for:

[0136] The proportional parameter command is obtained by multiplying the absolute value of the active power control deviation by the proportional conversion coefficient.

[0137] The integration parameter instruction module is specifically used for:

[0138] The integral parameter command is obtained by multiplying the absolute value of the active power control deviation by the reciprocal of the integral conversion coefficient.

[0139] The differential parameter instruction module is specifically used for:

[0140] The differential parameter command is obtained by multiplying the absolute value of the active control deviation by the differential conversion coefficient.

[0141] Preferably, in this embodiment of the invention, the active power instruction module is specifically used for:

[0142] The proportional parameter command, the integral parameter command, and the derivative parameter command are each multiplied by the active power control deviation and then added together to obtain the current active power command.

[0143] The photovoltaic field control device of this embodiment is used to implement the aforementioned photovoltaic field control method. Therefore, the specific implementation of the photovoltaic field control device can be found in the embodiment section of the photovoltaic field control method above. For example, the substation acquisition module 100, the active power command deviation module 200, the allocation coefficient module 300, the main station deviation allocation module 400, and the power output module 500 are respectively used to implement steps S101 to S105 in the above-mentioned photovoltaic field control method. Therefore, the specific implementation can be referred to the description of the corresponding embodiments, which will not be repeated here.

[0144] The following describes a photovoltaic field control system under power curtailment conditions provided by an embodiment of the present invention. The photovoltaic field control system described below can be referred to in correspondence with the photovoltaic field control method and photovoltaic field control device described above.

[0145] Please refer to Figure 6 , Figure 6 This is a structural block diagram of a photovoltaic field control system under power-limited conditions provided in an embodiment of the present invention.

[0146] Reference Figure 4 The photovoltaic field control system equipment includes a control substation 11 and multiple inverters 12, each of which is connected to a photovoltaic cell.

[0147] The control substation 11 is used for:

[0148] Obtain scheduling instructions, as well as the active power instructions corresponding to each of the multiple inverters 12.

[0149] The active power instruction deviation is calculated based on the scheduling instruction and multiple active power instructions.

[0150] Based on the real-time active power value of each inverter, the active power command and the scheduling command calculate the allocation coefficient corresponding to each inverter.

[0151] The total station deviation allocation for each inverter is calculated based on the allocation coefficient and the active power command deviation.

[0152] The total station deviation allocation is sent to the corresponding inverter so that the inverter 12 outputs electrical energy according to the total station deviation allocation.

[0153] As a preferred embodiment, the control substation is specifically used for:

[0154] The active power instruction deviation is obtained by subtracting each active power instruction from the scheduling instruction.

[0155] Preferably, the inverter is specifically used for:

[0156] Obtain the corresponding main station deviation allocation, the real-time active power value, and the previous active power command.

[0157] The active power control deviation is calculated based on the central station deviation allocation, the real-time active power value, and the previous active power command.

[0158] The proportional parameter instruction is calculated based on the active power control deviation and the proportional conversion coefficient.

[0159] The integral parameter instruction is calculated based on the active power control deviation and the integral conversion coefficient.

[0160] The differential parameter command is calculated based on the active power control deviation and the differential conversion coefficient.

[0161] The current active power command is calculated based on the proportional parameter command, the integral parameter command, the differential parameter command, and the active power control deviation.

[0162] The corresponding electrical energy is output according to the current active power command.

[0163] Preferably, the inverter is specifically used for:

[0164] The active power control deviation is obtained by adding the previous active power command to the real-time active power value and then subtracting the central station deviation allocation.

[0165] Preferably, the inverter is specifically used for:

[0166] The proportional parameter command is obtained by multiplying the absolute value of the active power control deviation by the proportional conversion coefficient.

[0167] The integral parameter command is obtained by multiplying the absolute value of the active power control deviation by the reciprocal of the integral conversion coefficient.

[0168] The differential parameter command is obtained by multiplying the absolute value of the active control deviation by the differential conversion coefficient.

[0169] Preferably, the inverter is specifically used for:

[0170] The proportional parameter command, the integral parameter command, and the derivative parameter command are each multiplied by the active power control deviation and then added together to obtain the current active power command.

[0171] The photovoltaic field control system of this embodiment is used to implement the aforementioned photovoltaic field control method. Therefore, the specific implementation of the photovoltaic field control system can be found in the embodiment section of the photovoltaic field control method above. Thus, the specific implementation can be referred to the description of the corresponding embodiments, which will not be repeated here.

[0172] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section.

[0173] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0174] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0175] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0176] The foregoing has provided a detailed description of a photovoltaic field control method, a photovoltaic field control device, and a photovoltaic field control system under power curtailment conditions provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A photovoltaic field control method under a power limiting condition, characterized in that, The method comprises the following steps: obtaining a scheduling instruction and a plurality of active instructions corresponding to the plurality of inverters respectively; the active instruction is an instruction generated by a control module of the inverter when the control module controls the output power of the inverter; calculating an active instruction deviation according to the scheduling instruction and the plurality of active instructions; the active instruction deviation corresponds to a deviation of the control substation as a whole corresponding to the scheduling instruction; calculating an allocation coefficient corresponding to each of the plurality of inverters according to an active real-time value of each of the plurality of inverters, the active instruction and the scheduling instruction; the allocation coefficient represents a ratio of the active real-time value of each of the plurality of inverters to the scheduling instruction; calculating a total station deviation allocation of each of the plurality of inverters according to the allocation coefficient and the active instruction deviation; sending the total station deviation allocation to the corresponding inverter, so that the inverter outputs power according to the total station deviation allocation; the step of outputting power by the inverter according to the total station deviation allocation comprises the following steps: the inverter obtains the corresponding total station deviation allocation, the active real-time value and the previous active instruction; calculating an active control deviation according to the total station deviation allocation, the active real-time value and the previous active instruction; calculating a proportional parameter instruction according to the active control deviation and a proportional conversion coefficient; calculating an integral parameter instruction according to the active control deviation and an integral conversion coefficient; calculating a differential parameter instruction according to the active control deviation and a differential conversion coefficient; calculating a current active instruction according to the proportional parameter instruction, the integral parameter instruction, the differential parameter instruction and the active control deviation; outputting corresponding power according to the current active instruction.

2. The method of claim 1, wherein, The step of calculating the active instruction deviation according to the scheduling instruction and the plurality of active instructions comprises the following step: subtracting each of the plurality of active instructions from the scheduling instruction to obtain the active instruction deviation.

3. The method of claim 1, wherein, The step of calculating the active control deviation according to the total station deviation allocation, the active real-time value and the previous active instruction comprises the following step: adding the active real-time value to the previous active instruction, and then subtracting the total station deviation allocation to obtain the active control deviation.

4. The method of claim 3, wherein, The step of calculating the proportional parameter instruction according to the active control deviation and the proportional conversion coefficient comprises the following step: multiplying the absolute value of the active control deviation by the proportional conversion coefficient to obtain the proportional parameter instruction. The step of calculating the integral parameter instruction according to the active control deviation and the integral conversion coefficient comprises the following step: multiplying the absolute value of the active control deviation by the inverse of the integral conversion coefficient to obtain the integral parameter instruction. The step of calculating the differential parameter instruction according to the active control deviation and the differential conversion coefficient comprises the following step: multiplying the absolute value of the active control deviation by the differential conversion coefficient to obtain the differential parameter instruction.

5. The method of claim 4, wherein, The step of calculating the current active instruction according to the proportional parameter instruction, the integral parameter instruction, the differential parameter instruction and the active control deviation comprises the following step: multiplying the proportional parameter instruction, the integral parameter instruction and the differential parameter instruction by the active control deviation respectively, and then adding them to obtain the current active instruction.

6. A photovoltaic field control device under a power limiting condition, characterized by, The method comprises the following steps: a substation obtaining module is configured to obtain a scheduling instruction and a plurality of active instructions corresponding to a plurality of inverters respectively; The active instruction is an instruction generated by a control module of the inverter when the control module controls the output power of the inverter. An active instruction deviation module is configured to calculate an active instruction deviation according to the scheduling instruction and the active instructions. A distribution coefficient module is configured to calculate a distribution coefficient of each inverter according to the real-time active value of each inverter, the active instruction and the scheduling instruction. A total station deviation distribution module is configured to calculate a total station deviation distribution of each inverter according to the distribution coefficient and the active instruction deviation. An electric energy output module is configured to send the total station deviation distribution to the corresponding inverter, so that the inverter outputs electric energy according to the total station deviation distribution. The inverter further comprises: An inverter acquisition module is configured to acquire the total station deviation distribution, the real-time active value and the previous active instruction. An active control deviation module is configured to calculate an active control deviation according to the total station deviation distribution, the real-time active value and the previous active instruction. A proportional parameter instruction module is configured to calculate a proportional parameter instruction according to the active control deviation and a proportional conversion coefficient. An integral parameter instruction module is configured to calculate an integral parameter instruction according to the active control deviation and an integral conversion coefficient. A differential parameter instruction module is configured to calculate a differential parameter instruction according to the active control deviation and a differential conversion coefficient. An active instruction module is configured to calculate a current active instruction according to the proportional parameter instruction, the integral parameter instruction, the differential parameter instruction and the active control deviation. An inverter electric energy output module is configured to output corresponding electric energy according to the current active instruction.

7. A photovoltaic field control system under a power limiting condition, characterized by, The control substation is configured to: acquire a scheduling instruction and active instructions corresponding to the inverters respectively; the active instruction is an instruction generated by a control module of the inverter when the control module controls the output power of the inverter; calculate an active instruction deviation according to the scheduling instruction and the active instructions; the active instruction deviation corresponds to a deviation of the control substation as a whole corresponding to the scheduling instruction; calculate a distribution coefficient of each inverter according to the real-time active value of each inverter, the active instruction and the scheduling instruction; calculate a total station deviation distribution of each inverter according to the distribution coefficient and the active instruction deviation; send the total station deviation distribution to the corresponding inverter, so that the inverter outputs electric energy according to the total station deviation distribution. The inverter is specifically configured to: acquire the total station deviation distribution, the real-time active value and the previous active instruction; calculate an active control deviation according to the total station deviation distribution, the real-time active value and the previous active instruction; calculate a proportional parameter instruction according to the active control deviation and a proportional conversion coefficient; calculate an integral parameter instruction according to the active control deviation and an integral conversion coefficient; calculate a differential parameter instruction according to the active control deviation and a differential conversion coefficient; and calculate a current active instruction according to the proportional parameter instruction, the integral parameter instruction, the differential parameter instruction and the active control deviation. According to the proportional parameter instruction, the integral parameter instruction, the differential parameter instruction and the active control deviation, a current active instruction is calculated; According to the current active instruction, corresponding electric energy is output.

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