A photovoltaic power station compensation adjustment optimization system and method

Abstract

The present invention belongs to the technical field of photovoltaic power station optimization, and specifically relates to a photovoltaic power station compensation adjustment optimization system and method, which divides the peak and non-peak power consumption periods, the stable and fluctuating photovoltaic access periods, and the strong and non-strong photovoltaic power generation periods by retrieving historical data, thereby determining whether the grid's adapted access object is an energy storage battery or photovoltaics based on the above-mentioned period division when identifying that the grid needs to access an external power supply, and can give priority to using energy storage batteries to obtain electricity instead of directly obtaining electricity from photovoltaic power stations, thereby greatly reducing the frequency of photovoltaic access to the grid, and reducing the number of switching times of reactive compensators, thereby reducing equipment wear and extending the service life of the equipment. At the same time, the scheduling strategy based on the period division enables the grid to dynamically adjust the output of energy storage batteries and photovoltaic power stations, thereby improving the flexibility of the system.

Description

Technical Field

[0001] The present invention belongs to the technical field of photovoltaic power station optimization, and in particular relates to a photovoltaic power station compensation regulation optimization system and method. Background Art

[0002] With the development of rural economy and the improvement of living standards, the popularity of household appliances has increased, resulting in a significant increase in electricity demand. In order to meet this growing demand for electricity, additional power supply equipment is needed. In rural areas, since most buildings are single-family houses with large roof areas and clear property rights, they are very suitable for installing distributed photovoltaic power stations. This feature has promoted the phenomenon of concentrated distribution of photovoltaic power stations in rural areas.

[0003] In rural power grids, voltage fluctuations and imbalances are easily caused due to long lines and uneven load distribution. When large photovoltaic power generation systems are connected to the grid, these problems may be further aggravated if there is a lack of effective management and regulation mechanisms. Therefore, in the application of photovoltaic power stations connected to the grid, it is necessary to introduce compensation and regulation equipment to adjust the reactive power in the grid to improve power supply stability.

[0004] The compensation and regulation equipment introduced in the prior art is generally a reactive compensator. The reactive compensator provides or absorbs necessary reactive power to maintain the stability of the grid by switching on and off when photovoltaic power is connected to the grid. Although the operation is simple, the use of reactive compensators alone for reactive compensation requires frequent switching on and off to maintain the stability of the grid when photovoltaic power is connected to the grid and causes large fluctuations in the grid. This not only affects the life of the equipment and invisibly increases maintenance costs, but may also cause transient interference and affect the stable operation of other electrical equipment. On the other hand, when the reactive demand in the grid changes rapidly, the reactive compensator has the hidden danger of being unable to respond in time, which can easily cause a lag in reactive compensation operation and lead to a continuous increase in the reactive power ratio, which will not only cause grid oscillations but also reduce the overall power factor of the grid, increasing the loss of the grid. Summary of the invention

[0005] The purpose of the present invention is to improve the deficiencies in the prior art and to provide a photovoltaic power station compensation adjustment optimization system and method, which can minimize the switching frequency of the reactive compensator while achieving the reactive compensation purpose by combining a reactive compensator with a battery energy storage system to form a hybrid compensation scheme.

[0006] The purpose of the present invention can be achieved through the following technical solutions: The first aspect of the present invention provides a photovoltaic power station compensation regulation optimization system, which is composed of a storage battery, a reactive power compensator, a power grid and a photovoltaic power station, wherein an important component of the photovoltaic power station is an inverter. The present invention includes the following modules: a power consumption period classification module, which is used to retrieve the historical power consumption log of the power supply area corresponding to the photovoltaic power station in the current season, and extract the power consumption period and power consumption from the historical power consumption log, thereby classifying the power consumption time interval of the power supply area within a day into peak power consumption period and non-peak power consumption period.

[0007] The photovoltaic access period classification module is used to summarize the access days and the access time intervals of the corresponding access days when the photovoltaic power grid is connected in history to divide the photovoltaic access period, and extract the power quality monitoring records of the access time interval, and then extract the monitoring date and monitoring time from the records to match the photovoltaic access period with the power quality monitoring records, and then classify the photovoltaic access period into a fluctuating access period and a stable access period.

[0008] The photovoltaic power generation period classification module is used to summarize the power generation days and the power generation time intervals of the corresponding power generation days when the photovoltaic power station generates power in history to divide the photovoltaic power generation period, and use the meter equipment installed in the photovoltaic power station to retrieve the time-series power generation collection data within the power generation time interval to match it with the photovoltaic power generation period, and classify the photovoltaic power generation period into strong power generation period and non-strong power generation period based on this.

[0009] The module for determining an adapted access object is used to determine an adapted access object based on the required access time and the classified power consumption period, photovoltaic access period and photovoltaic power generation period when identifying that the power grid needs to access an external power source.

[0010] The photovoltaic access adjustment module is used to adjust the operation of photovoltaic power station components when it is determined that the adapted access object is photovoltaic.

[0011] The reactive compensation regulation switching module is used to evaluate the switching demand of the reactive compensator when the photovoltaic power plant is connected to the power grid, and to detect the switching response in the switching operation of the required switching, to identify whether there is an untimely switching response, and to disconnect the photovoltaic access and switch to the energy storage battery access when the switching response is untimely.

[0012] The second aspect of the present invention proposes a compensation and adjustment optimization method for a photovoltaic power station, comprising the following steps: S1, retrieving the historical electricity consumption log of the power supply area corresponding to the photovoltaic power station in the current season, and extracting the electricity consumption time period and electricity consumption from the historical electricity consumption log, thereby classifying the electricity consumption time interval of the power supply area within a day into peak electricity consumption time period and non-peak electricity consumption time period.

[0013] S2. When photovoltaic power is connected to the grid in history, the access days and the access time intervals of the corresponding access days are summarized to divide the photovoltaic access time period, and the power quality monitoring records of the access time interval are extracted. Then, the monitoring date and monitoring time are extracted from the records to match the photovoltaic access period with the power quality monitoring records, and the photovoltaic access period is classified into a fluctuating access period and a stable access period.

[0014] S3. When the photovoltaic power station generates electricity in history, the power generation days and the power generation time intervals of the corresponding power generation days are summarized to divide the photovoltaic power generation period, and the electric meter equipment installed in the photovoltaic power station is used to retrieve the time-series power generation collection data within the power generation time interval to match it with the photovoltaic power generation period, and the photovoltaic power generation period is classified into strong power generation period and non-strong power generation period based on this.

[0015] S4. When identifying that the power grid needs to access an external power source, determine the appropriate access object based on the required access time and the classified power consumption period, photovoltaic access period and photovoltaic power generation period.

[0016] S5. When it is determined that the adapted access object is photovoltaic, the operation of the photovoltaic power station components is adjusted.

[0017] S6. Evaluate the switching demand of reactive power compensators when photovoltaic power is connected to the grid.

[0018] S7. When it is determined that there is a switching demand for the reactive power compensator, a switching operation is executed, and a switching response detection is performed during the execution to identify whether there is an untimely switching response, and then when it is identified that the switching response is untimely, the photovoltaic access is disconnected and switched to the energy storage battery access.

[0019] In combination with all the above technical solutions, the positive effects of the present invention are as follows: 1. The present invention retrieves historical data to classify peak and non-peak power consumption periods, stable and fluctuating periods of photovoltaic access, and strong and non-strong periods of photovoltaic power generation. Therefore, when identifying that the power grid needs to access an external power source, the grid's adapted access object is determined to be energy storage batteries or photovoltaics based on the above period classification. Energy storage batteries can be used to obtain electricity instead of directly obtaining electricity from photovoltaic power stations, thereby greatly reducing the frequency of photovoltaic access to the power grid, and the number of switching times of the reactive compensator is also reduced, thereby reducing equipment wear and extending the service life of the equipment. At the same time, the scheduling strategy based on time period division enables the power grid to dynamically adjust the output of energy storage batteries and photovoltaic power stations, thereby improving the flexibility of the system.

[0020] 2. The present invention adds switching response detection to the switching operation of the reactive compensator after determining that the adapted access object is photovoltaic. When it is identified that the switching response is not timely, the photovoltaic access is disconnected and switched to energy storage battery access. This can avoid the grid oscillation caused by reactive compensation lag, improve the stability of the grid, and provide an effective and reliable compensation method for reactive compensator lag compensation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

[0022] Figure 1 It is a schematic diagram of system module connection of the present invention.

[0023] Figure 2 It is a diagram of the steps for implementing the method of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Example 1

[0026] The present invention provides a photovoltaic power station compensation adjustment optimization system, which is composed of an energy storage battery, a reactive power compensator, a power grid and a photovoltaic power station, wherein an important component of the photovoltaic power station is an inverter.

[0027] It is important to understand that energy storage batteries can store excess electrical energy generated by photovoltaic power stations, and that energy storage batteries store and release energy through chemical reactions. During the discharge process, chemical reactions are usually controllable and can provide a relatively constant current output. Therefore, electrical energy can be released when photovoltaic output is unstable or intermittent, in order to smooth the output power of the photovoltaic power station and reduce the impact on the power grid.

[0028] What needs to be further understood is that since the electricity generated by photovoltaic power stations is direct current, and the electricity of the power grid is alternating current, an inverter is needed to perform DC-AC conversion when connecting photovoltaic power to the power grid. At the same time, the inverter can ensure that the converted alternating current matches the frequency and voltage of the power grid through adjustment so that it can be smoothly integrated into the power grid. In addition, the inverter can detect grounding faults and prevent safety accidents such as electrical fires. In short, the inverter can not only ensure the normal operation of photovoltaic access to the power grid, realize the effective use of photovoltaic power, but also improve the safety and stability of the system.

[0029] It should be added that since the electric energy released by the energy storage battery is also direct current, an inverter is also required for power conversion when the energy storage battery is connected to the power grid.

[0030] See also Figure 1As shown, the system provided by the present invention specifically includes a power consumption period classification module, a photovoltaic access period classification module and a photovoltaic power generation period classification module connected to the power consumption period classification module, an adaptation access object determination module connected to the power consumption period classification module, the photovoltaic access period classification module and the photovoltaic power generation period classification module, and a photovoltaic access adjustment module and a reactive compensation adjustment switching module connected to the adaptation access object determination module.

[0031] The electricity consumption period classification module is used to retrieve the historical electricity consumption log of the power supply area corresponding to the photovoltaic power station in the current season, and extract the electricity consumption period and electricity consumption from the historical electricity consumption log, thereby dividing the electricity consumption time interval of the power supply area within a day into peak electricity consumption period and non-peak electricity consumption period.

[0032] It should be added that the historical electricity consumption log is usually collected by smart meters and uploaded to the power company's cloud service platform. Specifically, the electricity consumption log is generally formed by the smart meter collecting electricity consumption at certain time intervals throughout the day, exemplarily every 2 hours.

[0033] It should be noted that when retrieving historical electricity consumption logs, we should focus on retrieving the historical electricity consumption logs of the current season. The reason is that there are obvious differences in electricity demand in different seasons. In the example of residential electricity consumption, in summer, the air conditioning load is higher; in winter, the heating load is larger; the electricity consumption patterns in spring and autumn are different, mainly depending on temperature changes. The historical electricity consumption logs of the current season can better represent the actual situation of the current season. Therefore, using the historical data of the current season is more valuable for reference.

[0034] In the specific implementation of the above scheme, extracting electricity consumption time periods and electricity consumption from historical electricity consumption logs is specifically implemented as follows: extracting timestamps from historical electricity consumption logs, where the timestamp contains date and time, thereby forming a log group with historical electricity consumption logs corresponding to the same date, and arranging the historical electricity consumption logs contained in the log group in chronological order.

[0035] The time of each historical electricity consumption log in each log group and the time of the previous historical electricity consumption log constitute the electricity consumption time period corresponding to the historical electricity consumption log, thereby dividing the electricity consumption time interval in a day into several electricity consumption time periods.

[0036] It should be emphasized that, since the first historical electricity consumption log in the log group does not have the previous historical electricity consumption log, the first historical electricity consumption log does not have a electricity consumption period.

[0037] In the example of the above scheme, assuming that the times corresponding to the historical electricity consumption logs in the log group are 8:00, 10:00, 12:00, 14:00, 16:00, 18:00, 20:00, 22:00, 24:00, 2:00, 4:00, 6:00, then the divided electricity consumption time periods are 8:00-10:00, 10:00-12:00, 12:00-14:00, 14:00-16:00, 16:00-18:00, 18:00-20:00, 20:00-22:00, 22:00-24:00, 24:00-2:00, 2:00-4:00, 4:00-6:00, 6:00-8:00.

[0038] The power consumption recorded in each historical power consumption log in each log group is subtracted from the power consumption recorded in the previous historical power consumption log to form the power consumption corresponding to the historical power consumption log.

[0039] In further implementation, the peak power consumption period and the non-peak power consumption period are classified as follows: all historical power consumption logs are classified according to the same power consumption time period to obtain historical power consumption logs classified for each power consumption period.

[0040] The power consumption of each log is extracted from the historical power consumption log classified in each power consumption period, and the median of these power consumptions is calculated, and then the obtained median is used as the effective power consumption of the power consumption period.

[0041] It should be understood that the median power consumption in the historical power consumption log classified in each power consumption period is selected as the effective power consumption in order to eliminate the influence of abnormal values ​​and to more accurately reflect the typical power consumption level of each power consumption period.

[0042] The average value of the effective power consumption in each power consumption period is calculated, and then the power consumption period when the effective power consumption is higher than the average value is determined as the peak power consumption period, and the power consumption period when the effective power consumption is not higher than the average value is determined as the non-peak power consumption period.

[0043] The present invention provides an objective statistical method by taking the average value of effective power consumption in each power consumption period as a division basis, which can reduce the deviation of subjective division.

[0044] The photovoltaic access period classification module is used to summarize the access days and the access time intervals of the corresponding access days when the photovoltaic power grid is historically connected, divide the photovoltaic access periods, and extract the power quality monitoring records of the access time intervals, and then extract the monitoring date and monitoring time from the records to match the photovoltaic access period with the power quality monitoring records, and then classify the photovoltaic access period into a fluctuating access period and a stable access period based on this.

[0045] In the optimized implementation of the above scheme, the photovoltaic access time periods are divided as follows: the access time interval of each access day is divided according to the division method of the electricity consumption time periods in the electricity consumption time interval of a day analyzed in the historical electricity consumption log to obtain several photovoltaic access time periods divided for each access day.

[0046] In the above implementation example, assuming that the photovoltaic access time interval on a certain access day is 10:00-20:00, then the photovoltaic access time periods obtained according to the division method of electricity consumption time periods are 10:00-12:00, 12:00-14:00, 14:00-16:00, 16:00-18:00, 18:00-20:00.

[0047] It should be added that in order to understand the impact of photovoltaic power generation on the power grid after it is connected to the power grid, power quality monitoring will be carried out during the process of photovoltaic power generation being connected to the power grid, thereby forming power quality monitoring records.

[0048] In the further optimization implementation of the above scheme, the matching of photovoltaic access time periods and power quality monitoring records is as follows: the monitoring date extracted from the power quality monitoring record is preliminarily classified with each access day to obtain the power quality monitoring record classified for each access day, and then the monitoring time extracted from the power quality monitoring record is matched with several photovoltaic access time periods corresponding to the classified access days. If the monitoring time of a power quality monitoring record falls within a photovoltaic access time period, the power quality monitoring record is used as the power quality monitoring record matched with the corresponding photovoltaic access time period, thereby obtaining several power quality monitoring records matched for each photovoltaic access time period within each access day, and finally the power quality monitoring records matched for the same photovoltaic access time period within each access day are summarized to obtain several power quality monitoring records matched for each photovoltaic access time period.

[0049] The power quality data in several power quality monitoring records matching each photovoltaic access period are compared, where the power quality data may be voltage fluctuation, frequency fluctuation, harmonic content, etc., and the maximum power quality data are extracted therefrom, where the maximum power quality data includes maximum and minimum power quality data. The maximum power quality data is then subtracted and divided by the maximum power quality data to obtain the power quality difference of each photovoltaic access period, where the greater the difference between the maximum and minimum power quality data, the greater the power quality difference.

[0050] The power quality difference of each photovoltaic access period is compared with the limited difference preset by the system. The limited difference is set to assist in the classification of photovoltaic access periods. If the power quality difference of a photovoltaic access period is less than the limited difference, it means that the power quality of the photovoltaic access period on different access dates is not much different and the distribution is relatively balanced. The power quality data in several power quality monitoring records corresponding to the photovoltaic access period are averaged and compared with the qualified power quality data to calculate the power quality compliance of the photovoltaic access period. The specific calculation formula of the power quality compliance is: In the formula represents the average power quality data, D0 represents the standard power quality data, e represents the natural constant, and vice versa, it means that there is a large power quality fluctuation in the photovoltaic access period. At this time, the power quality data in the corresponding power quality monitoring records of the photovoltaic access period are taken as the maximum power quality data, and compared with the standard power quality data, the power quality compliance degree of the photovoltaic access period is calculated. The specific calculation formula is: Where D max Indicates the maximum power quality data.

[0051] It needs to be explained that since the power quality data include voltage fluctuation, frequency fluctuation, harmonic content, etc., the smaller these data are, the smaller the fluctuation to the power grid is, and the better the power quality is.

[0052] It should be added that the qualified power quality data is determined by the power configuration of the power grid, such as voltage level and load nature, which can be extracted from the instructions for use by obtaining the power configuration parameters of the power grid.

[0053] When analyzing the compliance of the power quality in the photovoltaic access period, the present invention compares the power quality difference calculated based on the power quality data of each photovoltaic access period with the limited difference preset by the system. When the power quality difference is less than the limited difference, the power quality compliance analysis is performed based on the average power quality data in the photovoltaic access period. This is because when the power quality distribution is relatively balanced and stable, the average power quality data in the photovoltaic access period can better reflect the overall level of power quality, because the average value can more accurately reflect the long-term impact of photovoltaic access on power quality. When the power quality difference reaches the limited difference, the power quality compliance analysis is performed based on the maximum power quality data in the photovoltaic access period. This is because when there is a large fluctuation in power quality, the maximum value is used to represent the power quality under the most unfavorable conditions. Performing a power quality compliance analysis on it can reflect the compliance of the power quality of the power grid under the most unfavorable conditions.

[0054] The power quality compliance of each photovoltaic access period is compared with the system setting threshold. For example, the system setting threshold is 0.8, and the photovoltaic access periods that meet the system setting threshold are selected as stable access periods, and other photovoltaic access periods are selected as fluctuating access periods.

[0055] It should be understood that since photovoltaic power generation depends on light intensity, and light intensity varies with time, seasons and weather conditions, and the movement of clouds will also cause discontinuous changes in light intensity, this makes photovoltaic power generation relatively stable in some periods and more volatile in other periods. Therefore, when photovoltaic power generation is stable, connecting it to the grid will make the power quality close to the standard state and will not cause a major impact on the grid. When photovoltaic power generation is unstable, connecting it to the grid will cause large fluctuations in power quality, which can easily cause a major impact on the grid. This is why the photovoltaic access period shows the characteristics of stable access in some periods and fluctuating access in other periods.

[0056] The photovoltaic power generation period classification module is used to summarize the power generation days and the power generation time intervals of the corresponding power generation days when the photovoltaic power station generates power in history to divide the photovoltaic power generation period, and use the meter equipment installed in the photovoltaic power station to retrieve the time-series power generation collection data within the power generation time interval to match it with the photovoltaic power generation period, and classify the photovoltaic power generation period into a strong power generation period and a non-strong power generation period based on this.

[0057] In the specific implementation of the above scheme, the division of photovoltaic power generation time periods refers to the division of photovoltaic access time periods.

[0058] The present invention divides the photovoltaic access period and the photovoltaic power generation period by using the division method of the electricity consumption period to make the photovoltaic access period and the photovoltaic power generation period and the electricity consumption period in the same time frame, ensuring that the photovoltaic access period and the photovoltaic power generation period are aligned in time with the electricity consumption period.

[0059] In the further implementation of the above scheme, the matching of the time-series power generation collection data and the photovoltaic power generation period is similarly referred to the matching of the photovoltaic access period and the power quality monitoring record, as follows: the collection date is extracted from the time-series power generation collection data, and it is preliminarily classified with each power generation day to obtain the time-series power generation collection data classified for each power generation day, and then the collection period is extracted from the time-series power generation collection data and matched with several photovoltaic power generation periods corresponding to the classified power generation days. If the collection period of a certain power generation collection data falls within a certain photovoltaic power generation period, the power generation data is used as the power generation data matched with the corresponding photovoltaic power generation period, thereby obtaining several power generation data matched for each photovoltaic power generation period in each power generation day, and finally the power generation data matched for the same photovoltaic power generation period in each power generation day are summarized to obtain several power generation data matched for each photovoltaic power generation period.

[0060] In a further implementation of the above scheme, the strong power generation period and the non-strong power generation period are classified as follows: the median of several power generation data matched with each photovoltaic power generation period is calculated, and the median power generation is used as the effective power generation of the corresponding power generation period.

[0061] The effective power generation corresponding to each photovoltaic power generation period is averaged to obtain the average effective power generation, and then the power generation period corresponding to the effective power generation higher than the average is determined as the strong power generation period, and the power generation period corresponding to the effective power generation not higher than the average is determined as the non-strong power generation period.

[0062] It is important to understand that photovoltaic power generation is mainly determined by light intensity, which varies with the change of the solar altitude angle. Generally, light intensity gradually increases in the morning, reaches a peak at noon, gradually weakens in the afternoon, and drops to zero at night. Therefore, photovoltaic power generation is not strong throughout the entire power generation time range, and has the characteristics of strong power generation in some periods and weak power generation in other periods.

[0063] The adaptable access object determination module is used to determine the adaptable access object based on the demand access time and the classified power consumption period, photovoltaic access period and photovoltaic power generation period when identifying that the power grid needs to access the external power supply. The identification that the power grid needs to access the external power supply can be based on the need to access the external power supply when the power generation of the local power generation facilities (such as coal-fired power plants, natural gas power plants, etc.) of the power grid is insufficient to meet the current load demand or the sudden load increase causes the existing power generation facilities to be unable to meet the demand. The specific determination process is as follows: Based on the demand access time, the power consumption period, photovoltaic access period and photovoltaic power generation period to which the demand access time belongs are obtained, which are respectively recorded as T E , T A , T P .

[0064] T E , T A , T P Importing the confirmed model The adaptive access object AO is obtained. In the model, PP and NPP represent the peak power consumption period and the non-peak power consumption period, WA and SA represent the fluctuating access period and the stable access period, SP and NSP represent the strong power generation period and the non-strong power generation period, and ∧ represents and.

[0065] It should be understood that when the power grid needs to access an external power source, it is a period of stable access and strong power generation. At this time, whether it is a peak power consumption period or a non-peak power consumption period, the adaptive access object is photovoltaics. The reason is that photovoltaic power stations can provide green power output, maximize the use of renewable energy, and reduce costs. At the same time, because it is in a stable access period of power quality, even if photovoltaics are connected to the power grid, it will not cause a major impact on the power grid, and the switching frequency of the reactive compensator can be minimized. Moreover, since the power generation of photovoltaic power stations is relatively high during the period of strong power generation, sufficient power supply can be provided. In other situations, energy storage batteries are given priority as adaptive access objects.

[0066] It should be pointed out that when the adapted access object is an energy storage battery, since the energy storage battery has limited power reserves and cannot continuously provide a large amount of power for a long time, the power generated by photovoltaics can be used to supplement the energy storage battery when it is connected to the grid to release power.

[0067] The present invention retrieves historical data to classify peak and non-peak power consumption periods, stable and fluctuating periods of photovoltaic access, and strong and non-strong periods of photovoltaic power generation. Therefore, when identifying that the power grid needs to access an external power source, the present invention determines whether the grid's adapted access object is an energy storage battery or photovoltaics based on the above period classification. Energy storage batteries can be used to obtain electricity instead of directly obtaining electricity from photovoltaic power stations, thereby greatly reducing the frequency of photovoltaic access to the power grid, and the number of switching times of the reactive compensator is also reduced, thereby reducing equipment wear and extending the service life of the equipment. At the same time, the scheduling strategy based on time period division enables the power grid to dynamically adjust the output of energy storage batteries and photovoltaic power stations, thereby improving the flexibility of the system.

[0068] The photovoltaic access adjustment module is used to adjust the operation of photovoltaic power station components when it is determined that the adapted access object is photovoltaic. The specific adjustment is as follows: the output voltage, output frequency and grid voltage and frequency of the photovoltaic power station are monitored simultaneously at the required access time.

[0069] The monitored output voltage of the photovoltaic power station is compared with the grid voltage, and the output frequency of the photovoltaic power station is compared with the grid frequency for consistency. If inconsistency is identified, the inverter is used to synchronize the output voltage and output frequency of the photovoltaic power station with the grid voltage and frequency.

[0070] When the present invention determines that the adapted access object is photovoltaic, the inverter is used to synchronously adjust the output voltage and output frequency of the photovoltaic power station with the voltage and frequency of the power grid. This can ensure the synchronization between photovoltaic and the power grid when connected to the power grid, avoid the impact on the power grid at the time of initial access, and reduce the switching of reactive compensators to a certain extent.

[0071] The reactive compensation adjustment switching module is used to evaluate the switching demand of the reactive compensator when the photovoltaic is connected to the power grid, and to detect the switching response in the switching operation of the demand switching, to identify whether there is an untimely switching response, and to disconnect the photovoltaic access and switch to the energy storage battery access when the untimely switching response is identified.

[0072] Specifically, the switching demand of the reactive power compensator is judged as follows: during the process of photovoltaic access to the grid, power quality monitoring and inverter operation status monitoring are carried out, and based on the monitoring results, it is identified whether the power quality meets the standard and whether the inverter operation status is abnormal. When it is identified that the power quality does not meet the standard or the inverter operation is abnormal, it is judged that there is a switching demand for the reactive power compensator; otherwise, it is judged that there is no switching demand for the reactive power compensator.

[0073] The present invention does not directly switch on the reactive power compensator when photovoltaic power is connected to the power grid, but increases the switching demand evaluation of the reactive power compensator. Switching is performed only when it is judged that there is a switching demand. This can avoid frequent operation of the reactive power compensator when there is no actual demand, reduce equipment wear and failure rate, and in addition, by reasonably switching on the reactive power compensator, unnecessary energy consumption can be reduced.

[0074] Furthermore, the switching demand of the reactive power compensator is judged not only based on the power quality, but also based on whether the inverter is operating abnormally. This is because the inverter is a synchronous regulation device for photovoltaic access to the power grid. When the inverter is abnormal, it cannot provide the synchronous regulation function. At this time, the reactive power compensator is needed for switching.

[0075] Furthermore, the identification of untimely switching response can be carried out by referring to the equipment manual or data provided by the manufacturer based on the specifications of the reactive power compensator, determining the normal switching response time, and recording the time after the switching command is issued in the switching response detection. If switching is not achieved after the normal switching response time is reached, the untimely switching response is identified.

[0076] Example 2

[0077] Reference Figure 2 As shown, the present invention proposes a compensation and adjustment optimization method for a photovoltaic power station, comprising the following steps: S1, retrieving the historical electricity consumption log of the power supply area corresponding to the photovoltaic power station in the current season, and extracting the electricity consumption time period and the electricity consumption from the historical electricity consumption log, thereby classifying the electricity consumption time interval of the power supply area within a day into peak electricity consumption time period and non-peak electricity consumption time period.

[0078] S2. When photovoltaic power is connected to the grid in history, the access days and the access time intervals of the corresponding access days are summarized to divide the photovoltaic access time period, and the power quality monitoring records of the access time interval are extracted. Then, the monitoring date and monitoring time are extracted from the records to match the photovoltaic access period with the power quality monitoring records, and the photovoltaic access period is classified into a fluctuating access period and a stable access period.

[0079] S3. When the photovoltaic power station generates electricity in history, the power generation days and the power generation time intervals of the corresponding power generation days are summarized to divide the photovoltaic power generation period, and the electric meter equipment installed in the photovoltaic power station is used to retrieve the time-series power generation collection data within the power generation time interval to match it with the photovoltaic power generation period, and the photovoltaic power generation period is classified into strong power generation period and non-strong power generation period based on this.

[0080] S4. When identifying that the power grid needs to access an external power source, determine the appropriate access object based on the required access time and the classified power consumption period, photovoltaic access period and photovoltaic power generation period.

[0081] S5, when it is determined that the adapted access object is photovoltaic, adjusting the operation of the photovoltaic power station components;

[0082] S6. Evaluate the switching demand of reactive power compensators when photovoltaic power is connected to the grid.

[0083] S7. When it is determined that there is a switching demand for the reactive power compensator, a switching operation is executed, and a switching response detection is performed during the execution to identify whether there is an untimely switching response, and then when it is identified that the switching response is untimely, the photovoltaic access is disconnected and switched to the energy storage battery access.

[0084] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A photovoltaic power station compensation adjustment optimization system, characterized in that: It is composed of energy storage batteries, reactive power compensators, power grids and photovoltaic power stations, among which the important component of the photovoltaic power station is the inverter. The system also includes the following modules: The electricity consumption period classification module is used to retrieve the historical electricity consumption log of the power supply area corresponding to the photovoltaic power station in the current season, and extract the electricity consumption period and power consumption from the historical electricity consumption log, thereby classifying the electricity consumption time interval of the power supply area within a day into peak electricity consumption period and non-peak electricity consumption period; The photovoltaic access period classification module is used to summarize the access days and the access time intervals of the corresponding access days when the photovoltaic power grid is connected in history to divide the photovoltaic access period, and extract the power quality monitoring records of the access time interval, and then extract the monitoring date and monitoring time from the records to match the photovoltaic access period with the power quality monitoring records, and then classify the photovoltaic access period into a fluctuating access period and a stable access period based on this; The photovoltaic power generation period classification module is used to summarize the power generation days and the power generation time intervals of the corresponding power generation days when the photovoltaic power station generates power in history to divide the photovoltaic power generation period, and use the electric meter equipment installed in the photovoltaic power station to retrieve the time-series power generation collection data within the power generation time interval to match it with the photovoltaic power generation period, and classify the photovoltaic power generation period into strong power generation period and non-strong power generation period accordingly; An adaptive access object determination module is used to determine the adaptive access object based on the required access time and the classified electricity consumption period, the classified photovoltaic access period and the classified photovoltaic power generation period when identifying that the power grid needs to access an external power source; A photovoltaic access adjustment module is used to adjust the operation of photovoltaic power station components when it is determined that the adapted access object is photovoltaic; The reactive compensation regulation switching module is used to evaluate the switching demand of the reactive compensator when the photovoltaic power plant is connected to the power grid, and to detect the switching response in the switching operation of the required switching, to identify whether there is an untimely switching response, and to disconnect the photovoltaic access and switch to the energy storage battery access when the switching response is untimely.

2. A photovoltaic power station compensation adjustment optimization system as claimed in claim 1, characterized in that: The extraction of power consumption time period and power consumption from the historical power consumption log is implemented as follows: Extracting a timestamp from the historical electricity consumption log, where the timestamp includes the date and time, thereby forming a log group with the historical electricity consumption logs corresponding to the same date, and arranging the historical electricity consumption logs included in the log group in chronological order; The time of each historical electricity consumption log in each log group and the time of the previous historical electricity consumption log constitute the electricity consumption period corresponding to the historical electricity consumption log, thereby dividing the electricity consumption time interval in a day into several electricity consumption periods; The power consumption recorded in each historical power consumption log in each log group is subtracted from the power consumption recorded in the previous historical power consumption log to form the power consumption corresponding to the historical power consumption log.

3. A photovoltaic power station compensation adjustment optimization system as claimed in claim 1, characterized in that: The peak power consumption period and the non-peak power consumption period are classified as follows: Classify all historical electricity consumption logs according to the same electricity consumption time period to obtain historical electricity consumption logs classified by each electricity consumption time period; Extract the power consumption of each log from the historical power consumption log classified in each power consumption period, calculate the median of these power consumptions, and then use the obtained median as the effective power consumption of the power consumption period; The average value of the effective power consumption in each power consumption period is calculated, and then the power consumption period when the effective power consumption is higher than the average value is determined as the peak power consumption period, and the power consumption period when the effective power consumption is not higher than the average value is determined as the non-peak power consumption period.

4. A photovoltaic power station compensation adjustment optimization system as claimed in claim 2, characterized in that: The photovoltaic access period is divided into the following: The access time interval of each access day is divided according to the division method of the power consumption time periods in the power consumption time interval of a day analyzed in the historical power consumption log to obtain a number of photovoltaic access time periods divided for each access day.

5. A photovoltaic power station compensation adjustment optimization system as claimed in claim 4, characterized in that: The classification of the photovoltaic access period into the fluctuating access period and the stable access period is implemented as follows: The power quality data in several power quality monitoring records matching each photovoltaic access period are compared, and the maximum power quality data is extracted from them, and then the maximum power quality data is subtracted and divided by the maximum power quality data to obtain the power quality difference degree of each photovoltaic access period; The power quality difference of each photovoltaic access period is compared with the limited difference preset by the system. If the power quality difference of a photovoltaic access period is less than the limited difference, the power quality data in several power quality monitoring records corresponding to the photovoltaic access period are averaged and compared with the qualified power quality data to calculate the power quality compliance of the photovoltaic access period. Otherwise, the power quality data in several power quality monitoring records corresponding to the photovoltaic access period are taken as the maximum power quality data, and compared with the qualified power quality data to calculate the power quality compliance of the photovoltaic access period; The power quality compliance of each photovoltaic access period is compared with the system setting threshold, and the photovoltaic access period that reaches the system setting threshold is selected as the stable access period, and the other photovoltaic access periods are selected as the fluctuating access periods.

6. A photovoltaic power station compensation adjustment optimization system as claimed in claim 2, characterized in that: The classification process of the strong power generation period and the non-strong power generation period is as follows: Calculate the median of several power generation data matched in each photovoltaic power generation period, and use the median power generation as the effective power generation in the corresponding power generation period; The effective power generation corresponding to each photovoltaic power generation period is averaged to obtain the average effective power generation, and then the power generation period corresponding to the effective power generation higher than the average is determined as the strong power generation period, and the power generation period corresponding to the effective power generation not higher than the average is determined as the non-strong power generation period.

7. A photovoltaic power station compensation adjustment optimization system as claimed in claim 1, characterized in that: The process of determining the adapted access object is as follows: Based on the demand access time, the electricity consumption period, photovoltaic access period and photovoltaic power generation period to which the demand access time belongs are obtained, which are recorded as T E , T A , T P ; T E , T A , T P Importing the confirmed model The adaptive access object AO is obtained. In the model, PP and NPP represent the peak power consumption period and the non-peak power consumption period, WA and SA represent the fluctuating access period and the stable access period, SP and NSP represent the strong power generation period and the non-strong power generation period, and ∧ represents and.

8. A photovoltaic power station compensation adjustment optimization system as claimed in claim 1, characterized in that: The photovoltaic power station components are operated and adjusted as follows: Simultaneously monitor the output voltage, output frequency, and grid voltage and frequency of the PV power station during demand access time; The monitored output voltage of the photovoltaic power station is compared with the grid voltage, and the output frequency of the photovoltaic power station is compared with the grid frequency for consistency. If inconsistency is identified, the inverter is used to synchronize the output voltage and output frequency of the photovoltaic power station with the grid voltage and frequency.

9. A photovoltaic power station compensation adjustment optimization system as claimed in claim 1, characterized in that: The reactive power compensator switching demand evaluation process is as follows: During the process of photovoltaic power grid access, power quality monitoring and inverter operation status monitoring are carried out, and based on the monitoring results, it is identified whether the power quality meets the standards and whether the inverter operation status is abnormal. When it is identified that the power quality does not meet the standards or the inverter operation is abnormal, it is judged that there is a need to switch the reactive power compensator. Otherwise, it is judged that there is no need to switch the reactive power compensator.

10. A photovoltaic power station compensation adjustment optimization method, characterized in that: The following steps are involved: S1. Retrieve the historical electricity consumption log of the power supply area corresponding to the photovoltaic power station in the current season, and extract the electricity consumption period and electricity consumption from the historical electricity consumption log, thereby classifying the electricity consumption time interval of the power supply area within a day into peak electricity consumption period and non-peak electricity consumption period; S2. When photovoltaic power is connected to the grid in history, the access day and the access time interval of the corresponding access day are summarized to divide the photovoltaic access period, and the power quality monitoring record of the access time interval is extracted. Then, the monitoring date and monitoring time are extracted from the record to match the photovoltaic access period with the power quality monitoring record, and then the photovoltaic access period is classified into a fluctuating access period and a stable access period according to the above. S3. When the photovoltaic power station generates electricity in history, the power generation day and the power generation time interval of the corresponding power generation day are summarized to divide the photovoltaic power generation period, and the time-series power generation data collected within the power generation time interval are retrieved by using the electric meter equipment installed in the photovoltaic power station to match the photovoltaic power generation period, and the photovoltaic power generation period is classified into a strong power generation period and a non-strong power generation period accordingly; S4. When identifying that the power grid needs to access an external power source, determining an adapted access object based on the required access time and the classified electricity consumption period, the classified photovoltaic access period, and the classified photovoltaic power generation period; S5, when it is determined that the adapted access object is photovoltaic, adjusting the operation of the photovoltaic power station components; S6. Evaluate the switching demand of reactive power compensators when photovoltaic power is connected to the grid; S7. When it is determined that there is a switching demand for the reactive power compensator, a switching operation is executed, and a switching response detection is performed during the execution to identify whether there is an untimely switching response, and then when it is identified that the switching response is untimely, the photovoltaic access is disconnected and switched to the energy storage battery access.

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