Photovoltaic reactive power control method, device, equipment, storage medium and product

Abstract

The invention discloses a photovoltaic reactive power control method and device, equipment, a storage medium and a product. The method comprises the following steps: acquiring at least one preset time period in a day; for each preset time period, determining active and reactive load average data according to the active and reactive load historical data; obtaining the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access position of the photovoltaic power station, the capacity of the photovoltaic power station and the active output of the photovoltaic power station; according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access position of the photovoltaic power station, the capacity of the photovoltaic power station, the active power output of the photovoltaic power station, the active load average data and the reactive load average data, determining a preset time period reactive power output reference value in a preset time period; and taking the reactive power output reference value in the preset time period as a control target to control the reactive power output in the preset time period.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of photovoltaic technology, and in particular to a photovoltaic reactive power control method, device, equipment, storage medium and product. Background Art

[0002] The distribution network covers a wide area, has long lines and many nodes, and is very difficult to operate and manage. Among them, poor voltage quality and high power loss are two major issues that the power management department is particularly concerned about. Reasonable reactive power control methods can effectively improve the voltage quality and power loss of distribution lines. However, in traditional distribution lines, adjustable reactive resources are very scarce and cannot meet the control needs.

[0003] In recent years, with the rapid development of new power systems, more and more photovoltaic power stations have been connected to the distribution network. Photovoltaic power stations have good reactive power regulation capabilities, but are limited by the weak computing and communication capabilities of the distribution network. At present, power management departments usually only require the reactive power output of photovoltaic power stations based on relatively loose grid-connected specifications, for example, requiring the reactive power output of photovoltaic power stations to be kept near 0. Although this method is simple, it wastes the reactive power regulation capability of photovoltaic power stations. Summary of the invention

[0004] The present invention provides a photovoltaic reactive power control method, device, equipment, storage medium and product to achieve the purpose of improving the reactive power regulation capability of a photovoltaic power station.

[0005] In a first aspect, an embodiment of the present invention provides a photovoltaic reactive power control method, comprising:

[0006] Get at least one preset time period in a day;

[0007] For each of the preset time periods, obtaining active load historical data and reactive load historical data of the preset time period within a specified number of days;

[0008] Determine active load average data according to the active load historical data, and determine reactive load average data according to the reactive load historical data;

[0009] Obtain the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, and the active output of the photovoltaic power station;

[0010] Determine a reactive output reference value for a preset period of time within the preset period of time according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the average data of the active load, and the average data of the reactive load;

[0011] The reactive output of the preset period is controlled by taking the reactive output reference value of the preset period as a control target.

[0012] Optionally, divide the time periods of the day into peak, flat and trough periods;

[0013] The preset time period includes one or more of the peak time period, the flat time period, and the valley time period.

[0014] Optionally, it also includes segmenting the photovoltaic line according to the number of photovoltaic power stations arranged in the photovoltaic line;

[0015] Determine the reactive output reference value of each segment within the preset time period according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the average data of the active load, the average data of the reactive load, and the segmentation;

[0016] The reactive power output reference value of the preset time period corresponding to each segment is used as a control target to control the reactive power output of the preset time period of the segment.

[0017] Optionally, the specified number of days includes at least the number of days corresponding to a quarter.

[0018] Optionally, the photovoltaic power stations are numbered from small to large, with the largest number being N. pv ;

[0019] The reactive output reference value is determined based on a reactive output reference value calculation equation, and the reactive output reference value calculation equation satisfies:

[0020] Each number is less than N pv The reactive power output of the photovoltaic power station is balanced with the reactive power loss of a section of the line upstream of its access point and the reactive load it carries;

[0021] Nth pv The reactive output of a photovoltaic power station is balanced with the reactive losses of a section of line upstream and downstream of its access point as well as the reactive load it carries.

[0022] Optionally, the active load historical data and reactive load historical data are the active load data and reactive load data of the year before the current year.

[0023] In a second aspect, an embodiment of the present invention further provides a photovoltaic reactive power control device, comprising a first calculation module and a second calculation module;

[0024] The first calculation module is used for:

[0025] Get at least one preset time period in a day;

[0026] For each of the preset time periods, obtaining active load historical data and reactive load historical data of the preset time period within a specified number of days;

[0027] Determine active load average data according to the active load historical data, and determine reactive load average data according to the reactive load historical data;

[0028] Obtain the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, and the capacity of the photovoltaic power station;

[0029] Determine a calculation equation for a reactive output reference value for a preset period of time within the preset period of time according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the average active load data, and the average reactive load data;

[0030] The second calculation module is used for:

[0031] Obtaining active power output of the photovoltaic power station, and receiving a calculation equation for a reference value of reactive power output during a preset period of time within the preset period of time;

[0032] Determine the reactive output reference value of the preset period according to the calculation equation of the active output of the photovoltaic power station and the reactive output reference value of the preset period within the preset period;

[0033] The reactive output of the preset period is controlled by taking the reactive output reference value of the preset period as a control target.

[0034] In a third aspect, an embodiment of the present invention further provides an electronic device, comprising at least one processor, and a memory communicatively connected to the at least one processor;

[0035] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute any one of the photovoltaic reactive power control methods described in the embodiments of the present invention.

[0036] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement any one of the photovoltaic reactive power control methods recorded in the embodiments of the present invention when executed.

[0037] In a fifth aspect, an embodiment of the present invention further provides a computer program product, including a computer program, which, when executed by a processor, implements any one of the photovoltaic reactive power control methods recorded in the embodiments of the present invention.

[0038] Compared with the prior art, the beneficial effect of the present invention is that: the present invention proposes a photovoltaic reactive power control method, in which the reactive power output of the photovoltaic power station is optimized and set differently in different time periods according to the historical load data, the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station and the active output of the photovoltaic power station. The reactive output of the photovoltaic power station can be flexibly adjusted according to the load size and the active output size of the photovoltaic power station, and the voltage quality and power loss of the distribution line can be improved. In this scheme, based on the above-mentioned parameters, the balance relationship between the reactive load carried by each section of the line, the reactive loss of each section of the line and the photovoltaic reactive output is used as a determining factor for determining the reactive output of the photovoltaic power station. The reactive output determined by this method is used to perform reactive adjustment on the photovoltaic power station, which can significantly reduce power loss, improve voltage quality, and avoid serious low voltage problems in the distribution line. The method is simple and easy to implement, with small calculation amount, small communication amount, good confidentiality, and does not require remote real-time communication. It is suitable for distribution lines with limited computing power and communication capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a flow chart of a photovoltaic reactive power control method in an embodiment;

[0040] Figure 2 is another flow chart of photovoltaic reactive power control method in the embodiment;

[0041] Figure 3 is an active load curve and a reactive load curve for one day in the embodiment;

[0042] Figure 4 is the ratio of the active output of the photovoltaic power station to its capacity in one day in the embodiment;

[0043] Figure 5 It is the voltage of the first photovoltaic power station after the reactive power output is adjusted by the prior art in the embodiment;

[0044] Figure 6 It is the voltage of the second photovoltaic power station after the reactive power output is adjusted by using the prior art in the embodiment;

[0045] Figure 7 The terminal voltage after the reactive power output is adjusted by the prior art in the embodiment;

[0046] Figure 8 Schematic diagram of an electronic device in an embodiment. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0048] Embodiment 1

[0049] Figure 1 is a flow chart of the photovoltaic reactive power control method in the embodiment, refer to Figure 1 , photovoltaic reactive power control methods include:

[0050] S101. Obtain at least one preset time period in a day.

[0051] In this scheme, one preset time period corresponds to a load level of an electrical device, and one load level can correspond to multiple preset time periods;

[0052] For example, the above load levels may include a peak power consumption period, a level power consumption period, and a valley power consumption period. The peak power consumption period may include two (preset) periods of 10:00-12:00 and 14:00-19:00.

[0053] In this solution, the division of the above-mentioned preset time periods can be determined based on experience or historical data, and the specific division method is not limited.

[0054] S102. For each preset time period, obtain historical active load data and reactive load data of the preset time period within a specified number of days.

[0055] In this solution, the specific implementation of steps S102 to S106 is illustrated by taking a preset time period as an example. For example, a preset time period may be 10:00-12:00 or 14:00-19:00;

[0056] In this solution, steps S102 to S106 may be repeatedly performed according to actual needs to determine preset period reactive power reference values ​​corresponding to different preset period.

[0057] In this solution, the designated number of days can be set according to demand, for example, the designated number of days can be the number of days corresponding to the month, quarter, year, etc.

[0058] In this solution, active load historical data specifically refers to the active load data corresponding to a photovoltaic access distribution line, wherein a photovoltaic access distribution line may include multiple photovoltaic power stations, and active load historical data includes all active load data connected to the distribution line;

[0059] In this solution, for each photovoltaic power station, the active load historical data in a day includes active load data at multiple recording moments.

[0060] In this solution, reactive load historical data specifically refers to reactive load data corresponding to a photovoltaic access distribution line, wherein a photovoltaic access distribution line may include multiple photovoltaic power stations, and reactive load historical data includes all reactive load data connected to the distribution line;

[0061] In this solution, for each photovoltaic power station, the reactive load historical data in a day includes reactive data at multiple recording moments.

[0062] In this solution, the distribution lines corresponding to the active load historical data and the reactive load historical data are the same.

[0063] In this scheme, active load refers to the active power consumed by resistive load in the power system, and reactive load refers to the power of the non-working part of the power load in the power system where electric energy is continuously exchanged between the electric field and the magnetic field.

[0064] S103. Determine active load average data based on active load historical data, and determine reactive load average data based on reactive load historical data.

[0065] In this solution, the average active load data refers to the average value corresponding to the historical active load data, and the average reactive load data refers to the average value corresponding to the historical reactive load data.

[0066] S104. Obtain the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, and the active output of the photovoltaic power station.

[0067] In this solution, the rated voltage of the photovoltaic line refers to the voltage level of the photovoltaic system. For example, depending on the power generation capacity of the photovoltaic system, the voltage level can be 220V, 380V, 10kV, 35kV, etc.

[0068] The reactance per unit length of a photovoltaic line refers to the reactance part of the impedance per unit length of the distribution line. The impedance consists of resistance and reactance.

[0069] The PV line length refers to the total length of the main line of the distribution line;

[0070] The access location of a photovoltaic power station refers to the distance from the location where the photovoltaic power station is connected to the main line of the distribution line to the head end of the distribution line;

[0071] Photovoltaic power station capacity refers to the installed capacity of photovoltaic power stations connected to the distribution lines;

[0072] The active output of a photovoltaic power station refers to the active output of a photovoltaic power station at a time, which is included in the selected preset time period.

[0073] S105. Determine a reactive output reference value for a preset period of time within a preset period of time according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the average active load data, and the average reactive load data.

[0074] In this solution, there is no limitation on the method of determining the reactive output reference value for the preset period based on the above parameters. For example, the reactive output reference value for the preset period can be calculated based on a trained neural network model and a function equation determined by simulation.

[0075] S106. Using the reactive output reference value of the preset period as a control target to control the reactive output of the preset period.

[0076] In this solution, the reactive output reference value of the preset time period is used as the target value to adjust the reactive output of the photovoltaic power station. There is no limitation on the method of adjusting the reactive output of the photovoltaic power station, which is the same as the prior art and will not be described in detail.

[0077] This embodiment proposes a photovoltaic reactive power control method, in which the reactive power output of the photovoltaic power station is optimized and set differently in different time periods according to the historical load data, the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station and the active output of the photovoltaic power station. The reactive output of the photovoltaic power station can be flexibly adjusted according to the load size and the active output size of the photovoltaic power station, thereby improving the voltage quality and power loss of the distribution line. In this scheme, based on the above-mentioned parameters, the reactive load carried by each section of the line, the reactive loss of each section of the line and the balance relationship between the photovoltaic reactive output are used as the determining factors for determining the reactive output of the photovoltaic power station. The reactive output determined by this method is used to perform reactive adjustment on the photovoltaic power station, which can significantly reduce power loss, improve voltage quality, and avoid serious low voltage problems in the distribution line.

[0078] exist Figure 1 On the basis of the scheme shown, in one possible implementation scheme, the time periods of a day are divided into peak time periods, flat time periods and off-peak time periods; the preset time periods include one or more of the peak time periods, flat time periods and off-peak time periods.

[0079] Exemplarily, in this solution, the peak hours may be 10:00-12:00 and 14:00-19:00, the flat hours may be 8:00-10:00, 12:00-14:00 and 19:00-24:00, and the trough hour may be 00:00-8:00.

[0080] Exemplarily, in this solution, reactive power reference values ​​corresponding to peak time periods, flat time periods, and valley time periods can be determined, including:

[0081] Divide the time periods of a day into peak periods, flat periods and trough periods;

[0082] Get the first active load historical data and the first reactive load historical data during the peak period, the second active load historical data and the second reactive load historical data during the flat period, and the third active load historical data and the third reactive load historical data during the valley period within the specified number of days;

[0083] Determine first active load average data according to the first active load historical data, and determine first reactive load average data according to the first reactive load historical data;

[0084] Determine the second active load average data according to the second active load historical data, and determine the second reactive load average data according to the second reactive load historical data;

[0085] Determine third active load average data according to the third active load historical data, and determine third reactive load average data according to the third reactive load historical data;

[0086] Obtain the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, and the active output of the photovoltaic power station;

[0087] Determine the reactive power output reference value during peak hours according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active power output of the photovoltaic power station, the first active load average data, and the first reactive load average data;

[0088] Determine the reactive power output reference value during the flat period according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active power output of the photovoltaic power station, the second active load average data, and the second reactive load average data;

[0089] The reference value of reactive output during the off-peak period is determined based on the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the average data of the third active load, and the average data of the third reactive load.

[0090] In this scheme, for different time periods, the corresponding reactive output reference value is used as the control target to adjust the reactive output of the photovoltaic motor, including:

[0091] The reactive power output during peak hours is controlled by taking the reactive power output reference value during peak hours as the control target;

[0092] The reactive power output reference value during the flat period is used as the control target to control the reactive power output during the flat period;

[0093] The reactive power output reference value during the valley period is used as the control target to control the reactive power output during the valley period.

[0094] Based on any of the above solutions, in one possible implementation, the photovoltaic line is further divided into sections according to the number of photovoltaic power stations arranged in the photovoltaic line;

[0095] Determine the reactive output reference value of each segment within the preset time period according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the average data of the active load, the average data of the reactive load, and the segmentation;

[0096] The reactive power output reference value of the preset time period corresponding to each segment is used as the reactive power output of the preset time period of the control target control segment.

[0097] In this scheme, for a distribution line, if j photovoltaic power stations are connected to the distribution line, the j photovoltaic power stations will divide the trunk line of the distribution line into j+1 sections.

[0098] In this scheme, when j is greater than 1, the number of the last photovoltaic power station is set to N pv , determining the preset period reactive power reference value of each segment within the preset period includes:

[0099] When j = 1, 1 <j<N pv , j = N pv When the first calculation equation, the second calculation equation and the third calculation equation are respectively used to determine the reactive power reference value of the corresponding preset time period.

[0100] In this scheme, when j is 1 and only one photovoltaic power station is connected to the trunk line of the distribution line, the reference value of reactive output of each segment in the preset period of time is determined as follows:

[0101] The third calculation equation is used to determine the reactive power output reference value for the corresponding preset time period.

[0102] In this solution, the active output of the photovoltaic power station is set to the active output of the j-th photovoltaic power station corresponding to the reactive output reference value of a preset time period of a certain segment.

[0103] In this solution, the functional formulas of the first calculation equation, the second calculation equation, and the third calculation equation are set to be different, and their specific functional formulas are determined based on simulation experiments.

[0104] Among them, when conducting simulation experiments, the first calculation equation, the second calculation equation, and the third calculation equation are configured to at least satisfy the entire photovoltaic line so that the reactive load of each line section, the reactive loss of each line section, and the photovoltaic reactive output are balanced.

[0105] Based on the scheme of determining the reactive power output reference value of each segment within the preset time period, in one possible implementation scheme, the photovoltaic power stations are numbered from small to large, and the largest number is recorded as N. pv ;

[0106] The reactive output reference value is determined based on the reactive output reference value calculation equation, and the reactive output reference value calculation equation satisfies:

[0107] Each number is less than N pv The reactive power output of the photovoltaic power station is balanced with the reactive power loss of a section of the line upstream of its access point and the reactive load it carries;

[0108] Nth pv The reactive output of a photovoltaic power station is balanced with the reactive losses of a section of line upstream and downstream of its access point as well as the reactive load it carries.

[0109] In this scheme, the specific form of the reactive output reference value calculation equation is:

[0110]

[0111] In the formula, Represents the reactive power output reference value, L j represents the access location of the jth photovoltaic power station, x0 represents the reactance per unit length of the photovoltaic line, Indicates the average data of active load, S j represents the capacity of the j-th photovoltaic power station, Represents the average data of reactive load, represents the active power output of the j-th PV power station at time t, U N Indicates, L represents the length of the photovoltaic line, τ s Indicates a preset time period.

[0112] Based on any of the foregoing solutions, in one possible implementation scheme, the designated days at least include days corresponding to a quarter.

[0113] On the basis of any of the above-mentioned schemes, in one possible implementation scheme, the historical data of active load and the historical data of reactive load are set to the active load data and reactive load data of the year before the current year.

[0114] Figure 2 is another photovoltaic reactive power control method flow chart in the embodiment, refer to Figure 2 Based on any of the above solutions, in one possible implementation scheme, the photovoltaic reactive power control method includes:

[0115] S201. Divide the time periods of a day into peak period, flat period and valley period.

[0116] S202. Obtain the first active load historical data and the first reactive load historical data during the peak period, the second active load historical data and the second reactive load historical data during the flat period, and the third active load historical data and the third reactive load historical data during the valley period within the specified number of days.

[0117] In this solution, the designated days are set as the days corresponding to the quarter, and the above-mentioned historical data are set to use the active load data and reactive load data of the year before the current year.

[0118] S203. Determine first active load average data according to the first active load historical data, and determine first reactive load average data according to the first reactive load historical data.

[0119] In this scheme, the first active load average data is calculated according to the following formula:

[0120]

[0121] In this scheme, the first reactive load average data is calculated according to the following formula:

[0122]

[0123] In the above formula, Indicates the average data of the first active load, represents the average data of the first reactive load, T represents the period (month) corresponding to the quarter, d represents the date within T, N load represents the total number of load nodes in the distribution line, Γ high represents the peak period, t represents Γ high Moment within.

[0124] S204. Determine second active load average data according to the second active load historical data, and determine second reactive load average data according to the second reactive load historical data.

[0125] In this scheme, the first active load average data is calculated according to the following formula:

[0126]

[0127] In this scheme, the first reactive load average data is calculated according to the following formula:

[0128]

[0129] In the above formula, Indicates the average data of the second active load, represents the average data of the second reactive load, T represents the period (month) corresponding to the quarter, d represents the date within T, N loadrepresents the total number of load nodes in the distribution line, Γ mid represents the flat period, t represents Γ mid Moment within.

[0130] S205. Determine third active load average data according to the third active load historical data, and determine third reactive load average data according to the third reactive load historical data.

[0131] In this solution, the third active load average data is calculated according to the following formula:

[0132]

[0133] In this solution, the third reactive load average data is calculated according to the following formula:

[0134]

[0135] In the above formula, Indicates the average data of the third active load, represents the average data of the third reactive load, T represents the period (month) corresponding to the quarter, d represents the date within T, N load represents the total number of load nodes in the distribution line, Γ low represents the low period, t represents Γ low Moment within.

[0136] S206. Obtain the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, and the active output of the photovoltaic power station.

[0137] S207. Determine the reactive output reference value during the peak period according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the first active load average data, and the first reactive load average data.

[0138] In this scheme, the reference value of reactive power output during peak hours is determined according to the following formula:

[0139]

[0140] In the formula, It indicates the reference value of reactive power output during peak hours. The other parameters have the same meanings as those recorded in the above scheme.

[0141] S208. Determine the reactive output reference value during the flat period according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the second active load average data, and the second reactive load average data.

[0142] In this scheme, the reference value of reactive power output during the flat period is determined according to the following formula:

[0143]

[0144] In the formula, It indicates the reference value of reactive power output during the flat period. The other parameters have the same meanings as those recorded in the above scheme.

[0145] S209. Determine the reactive output reference value during the off-peak period according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the third active load average data, and the third reactive load average data.

[0146] In this scheme, the reference value of reactive power output during peak hours is determined according to the following formula:

[0147]

[0148] In the formula, It indicates the reference value of reactive power output during off-peak period. The other parameters have the same meanings as those recorded in the above scheme.

[0149] Combined with steps S207 to S209, where P j t The data is obtained through real-time monitoring of the photovoltaic power station, and the remaining parameters are set and processed into numerical values ​​by the power management department in priority, and then sent to the photovoltaic power station.

[0150] In this scheme, 1 <j<N pv ,t∈Γ high , taking the calculation of the reactive power reference value during peak hours as an example, the remaining parameters are set to be processed into numerical values ​​by the power management department first and then sent to the photovoltaic power station. Specifically:

[0151] First, the power management department determines the parameters of the peak period reactive power output reference value based on the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the first active load average data, and the first reactive load average data:

[0152]

[0153] Secondly, the calculation equation for the reactive power reference value during peak hours determined by the power management department is:

[0154]

[0155] In the above formula, except for P j tIn addition, each of the remaining parameters (including a, b, c, and d) are processed and calculated by the power management department, and then the calculated values ​​are brought into the formula;

[0156] Finally, the power management department sends the above formula with the calculated values ​​to the photovoltaic power station, and the photovoltaic power station itself measures the active output P j t , P j t Substitute it into the formula of the calculated value to obtain the corresponding

[0157] Exemplarily, as an optional solution, the method can also be configured at the power department end, which completes all reactive power output reference value calculations and then sends the calculated reactive power output reference values ​​to the photovoltaic power station end, so that the photovoltaic power station completes reactive power output control based on the reactive power output reference values.

[0158] S210. Use the reactive power output reference value during the peak period as a control target to control the reactive power output during the peak period.

[0159] S211. Taking the reactive output reference value during the flat period as the control target, the reactive output during the flat period is controlled.

[0160] S212. Taking the reactive power output reference value during the valley period as the control target to control the reactive power output during the valley period.

[0161] In combination with steps S210 to S212, in this solution, specifically for each photovoltaic power station, the reactive output reference value of the corresponding time period is used as the target value for adjusting the reactive output of the photovoltaic power station in the time period.

[0162] In this solution, a photovoltaic power station is configured to adjust its own reactive power output.

[0163] In this solution, the issues of data communication and data confidentiality are taken into consideration, and data preprocessing (in each formula in steps S207 to S209, except P j t The processing and calculation of each parameter except the above parameters are completed in the power department, and the real-time control (obtaining active power output, further calculating reactive power output reference value, and controlling reactive power output according to reactive power output reference value) is completed in the photovoltaic power station;

[0164] In this solution, the purpose of setting up designated data operations at both ends of the power department and the photovoltaic power station is to:

[0165] The specific reasons are as follows: the power department can obtain detailed historical load data, line parameters, and the access location and capacity of each photovoltaic power station. However, due to the limitations of distribution network communication capabilities and confidentiality requirements, these raw data cannot be sent directly to each photovoltaic power station;

[0166] PV power stations can monitor their own active power output in real time. If the active power output is sent to the power department, the power department will calculate the corresponding reactive power reference value and then send it back to the PV power station, which will cause a certain degree of waste of communication resources.

[0167] Therefore, in this solution, all coefficients except the active output of the photovoltaic power station itself in the reactive power output reference value calculation equation are preprocessed into numerical values ​​at the power department end, and a processed formula is sent to the photovoltaic power station in each time period (peak period, flat period, and valley period), and then the reactive power output reference value calculation is completed at the photovoltaic power station end;

[0168] In this formula, only the active output of the PV power station itself is an unknown variable, and the rest are calculated values. This can take into account less data communication (the formula is only sent once in each period), good data confidentiality (there is no need to send the original data to the PV power station), and good real-time performance (the PV power station can adjust its own reactive output in real time according to its own monitored active output and the received formula).

[0169] For example, a 10kV LGJ-150 distribution line to which two photovoltaic power stations are connected is selected to illustrate the beneficial effects of this solution.

[0170] The applicable period T for obtaining the reactive power output reference value of the photovoltaic power station of the line is from June 1 to August 31;

[0171] The peak hours of load are 10:00-12:00 and 14:00-19:00, the flat hours are 8:00-10:00, 12:00-14:00 and 19:00-24:00, and the valley hour is 00:00-8:00;

[0172] The line is connected to two photovoltaic power stations with capacities of 1MW and 1.5MW respectively, and the access locations of the photovoltaic power stations are 7.8km and 15.2km respectively; the rated voltage of the photovoltaic line is 10kV, the reactance per unit length of the photovoltaic line is 0.384Ω, and the length of the photovoltaic line is 16.9km;

[0173] The photovoltaic power station with a connection location of 7.8 km is numbered as 1, and the photovoltaic power station with a connection location of 15.2 km is numbered as 2;

[0174] According to the load history data from June 1 to August 31 of the previous year, the average data of the first active load and the first reactive load during the peak period were 2.77MW and 1.05Mvar respectively;

[0175] The average data of the second active load and the second reactive load during the flat period are 2.31MW and 0.70Mvar respectively;

[0176] The third average active load data and the third average reactive load data during the off-peak period are 1.73MW and 0.49Mvar respectively.

[0177] Based on the above equation, the above parameters are substituted into the equation to obtain the reactive power reference value of the first photovoltaic power station during the peak period:

[0178]

[0179] The reference value of reactive power output of the second photovoltaic power station during peak hours is:

[0180]

[0181] The reactive power reference value of the first photovoltaic power station in the flat period is obtained as follows:

[0182]

[0183] The reference value of reactive power output of the second photovoltaic power station during the flat period is:

[0184]

[0185] The reactive power output reference value of the first photovoltaic power station during the off-peak period is obtained as follows:

[0186]

[0187] The reference value of reactive power output of the second photovoltaic power station during the off-peak period is:

[0188]

[0189] Figure 3 are the active load curve and reactive load curve of one day in the embodiment, Figure 4 is the ratio of the active output of the photovoltaic power station to its capacity in one day in the embodiment. Figure 3 and Figure 4 In the scenario shown, the reactive power output of the photovoltaic power station is adjusted by using the method of this solution and the conventional method respectively;

[0190] The conventional method sets the reactive power output of the photovoltaic power station to 0. Figure 5 is the voltage of the first photovoltaic power station (L1 position) after the reactive power output is adjusted by the prior art in the embodiment; Figure 6 is the voltage of the second photovoltaic power station (at position L2) after the reactive output is adjusted by the prior art in the embodiment; Figure 7 The terminal voltage after the reactive power output is adjusted by the prior art in the embodiment;

[0191] refer to Figure 5 to Figure 7Compared with the conventional method, the method of the present invention increases the per-unit values ​​of the voltage of the first photovoltaic power station, the voltage of the second photovoltaic power station and the terminal voltage by 0.025, 0.048 and 0.048 respectively on average, which significantly improves the voltage quality and avoids serious low voltage problems in the distribution lines.

[0192] Under the method of the present invention, the power loss of the distribution line is 2.33MW, while under the conventional method, the power loss of the distribution line is 2.98MW. It can be seen that the power loss of the method of the present invention is reduced by 21.8% compared with the conventional method, and the loss reduction effect is significant.

[0193] The method proposed in this scheme is simple and easy to implement, with small computational complexity and communication volume, and does not require remote real-time communication. It is suitable for distribution lines with limited computing and communication capabilities.

[0194] Embodiment 2

[0195] This embodiment provides a photovoltaic reactive power control device, including a first calculation module and a second calculation module. The first calculation module is used for:

[0196] Get at least one preset time period in a day;

[0197] For each preset period, obtain the historical data of active load and reactive load in the preset period within the specified number of days;

[0198] Determine the average active load data according to the historical active load data, and determine the average reactive load data according to the historical reactive load data;

[0199] Obtain the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, and the capacity of the photovoltaic power station;

[0200] Determine a calculation equation for a reactive output reference value for a preset period of time within the preset period of time according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the average active load data, and the average reactive load data;

[0201] The second calculation module is used for:

[0202] Obtaining active power output of the photovoltaic power station, and receiving a calculation equation for a reference value of reactive power output during a preset period of time within the preset period of time;

[0203] Determine the reactive output reference value of the preset period according to the calculation equation of the active output of the photovoltaic power station and the reactive output reference value of the preset period within the preset period;

[0204] The reactive power output reference value of the preset period is used as the control target to control the reactive power output of the preset period.

[0205] Exemplarily, in this embodiment, the first calculation module may be configured at the power department end, and the second calculation module may be configured at the photovoltaic power station end.

[0206] In this embodiment, the photovoltaic reactive power control unit can be specifically configured to implement any photovoltaic reactive power control method recorded in Embodiment 1. The implementation process and beneficial effects of the method are the same as the corresponding contents recorded in Embodiment 1, and the specific contents will not be described in detail.

[0207] Exemplarily, as an implementation scheme, the photovoltaic reactive power control device may include a photovoltaic reactive power control unit:

[0208] Photovoltaic reactive power control unit is used for:

[0209] Get at least one preset time period in a day;

[0210] For each preset period, obtain the historical data of active load and reactive load in the preset period within the specified number of days;

[0211] Determine the average active load data according to the historical active load data, and determine the average reactive load data according to the historical reactive load data;

[0212] Obtain the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, and the active output of the photovoltaic power station;

[0213] The reactive output reference value of a preset time period within the preset time period is determined according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the average active load data, and the average reactive load data.

[0214] In this solution, the photovoltaic reactive power control unit can be configured at the power department end. After the power department end completes the reference value of the reactive output reference value, the reactive output reference value is sent to the photovoltaic power station end, so that the photovoltaic power station completes the reactive output control according to the reactive output reference value.

[0215] Embodiment 3

[0216] Figure 8A schematic diagram of the structure of an electronic device 10 that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0217] like Figure 8 As shown, the electronic device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0218] A number of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0219] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as a photovoltaic reactive power control method.

[0220] In some embodiments, the photovoltaic reactive power control method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the photovoltaic reactive power control method described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to execute the photovoltaic reactive power control method in any other appropriate manner (e.g., by means of firmware).

[0221] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0222] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0223] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, device, or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0224] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0225] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0226] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0227] Embodiment 4

[0228] This embodiment provides a computer program product, including a computer program. When the computer program is executed by a processor, it implements any photovoltaic reactive power control method recorded in the embodiments of the present invention. The photovoltaic reactive power control method and beneficial effects are the same as the corresponding contents recorded in Embodiment 1, and will not be repeated here.

[0229] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A photovoltaic reactive power control method, characterized in that: include: Get at least one preset time period in a day; For each of the preset time periods, obtaining active load historical data and reactive load historical data of the preset time period within a specified number of days; Determine active load average data according to the active load historical data, and determine reactive load average data according to the reactive load historical data; Obtain the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, and the active output of the photovoltaic power station; Determine a reactive output reference value for a preset period of time within the preset period of time according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the average data of the active load, and the average data of the reactive load; The reactive output of the preset period is controlled by taking the reactive output reference value of the preset period as a control target.

2. The photovoltaic reactive power control method according to claim 1, characterized in that: Divide the time periods of a day into peak periods, flat periods and trough periods; The preset time period includes one or more of the peak time period, the flat time period, and the valley time period.

3. The photovoltaic reactive power control method according to claim 1, characterized in that: It also includes segmenting the photovoltaic line according to the number of photovoltaic power stations set up in the photovoltaic line; Determine the reactive output reference value of each segment within the preset time period according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the active output of the photovoltaic power station, the average data of the active load, the average data of the reactive load, and the segmentation; The reactive power output reference value of the preset time period corresponding to each segment is used as a control target to control the reactive power output of the preset time period of the segment.

4. The photovoltaic reactive power control method according to claim 1, characterized in that: The specified number of days at least includes the number of days corresponding to a quarter.

5. The photovoltaic reactive power control method according to claim 3, characterized in that: Number the photovoltaic power stations from small to large, and record the largest number as N pv ; The reactive output reference value is determined based on a reactive output reference value calculation equation, and the reactive output reference value calculation equation satisfies: Each number is less than N pv The reactive power output of the photovoltaic power station is balanced with the reactive power loss of a section of the line upstream of its access point and the reactive load it carries; Nth pv The reactive output of a photovoltaic power station is balanced with the reactive losses of a section of line upstream and downstream of its access point as well as the reactive load it carries.

6. The photovoltaic reactive power control method according to claim 1, characterized in that: The active load historical data and reactive load historical data are the active load data and reactive load data of the previous year relative to the current year.

7. A photovoltaic reactive power control device, characterized in that: comprising a first computing module and a second computing module; The first calculation module is used for: Get at least one preset time period in a day; For each of the preset time periods, obtaining active load historical data and reactive load historical data of the preset time period within a specified number of days; Determine active load average data according to the active load historical data, and determine reactive load average data according to the reactive load historical data; Obtain the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, and the capacity of the photovoltaic power station; Determine a calculation equation for a reactive output reference value for a preset period of time within the preset period of time according to the rated voltage of the photovoltaic line, the reactance per unit length of the photovoltaic line, the length of the photovoltaic line, the access location of the photovoltaic power station, the capacity of the photovoltaic power station, the average active load data, and the average reactive load data; The second calculation module is used for: Obtaining active power output of the photovoltaic power station, and receiving a calculation equation for a reference value of reactive power output during a preset period of time within the preset period of time; Determine the reactive output reference value of the preset period according to the calculation equation of the active output of the photovoltaic power station and the reactive output reference value of the preset period within the preset period; The reactive output of the preset period is controlled by taking the reactive output reference value of the preset period as a control target.

8. An electronic device, characterized in that: comprising at least one processor, and a memory communicatively connected to the at least one processor; The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the photovoltaic reactive power control method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the photovoltaic reactive power control method according to any one of claims 1 to 6 when executed.

10. A computer program product, characterized in that The invention comprises a computer program, which, when executed by a processor, implements the photovoltaic reactive power control method according to any one of claims 1 to 6.

Images