Quick response control method for magnetic pressure mixed control type dynamic reactive power compensation device

Abstract

The invention relates to the technical field of reactive power compensation, in particular to a quick response control method of a magnetic pressure mixed control type dynamic reactive power compensation device. The method comprises the following steps: predicting prediction compensation amounts at various moments in the future; according to the predicted active power and the power factor, determining a compensation amount value interval required for increasing the power factor to a preset target power factor range; according to the overall fluctuation characteristics of the predicted active and reactive power sequences and the quantitative deviation degree between each predicted compensation amount and the compensation amount value interval, determining a basic compensation amount; determining the magnetic control compensation weight at each moment according to the deviation characteristics of the active power sequence and the reactive power sequence and the instantaneous change rate of a power change curve constructed by fusing the active power sequence and the reactive power sequence; and dividing the basic compensation amount into a magnetic control compensation amount and an electric control compensation amount according to the magnetic control compensation weight, and cooperatively controlling the magnetic control compensation device and the electric control compensation device to output the compensation amount at the corresponding moment.

Description

Technical Field

[0001] The present invention relates to the technical field of reactive power compensation, and in particular to a fast response control method for a magnetic-pressure hybrid control type dynamic reactive power compensation device. Background Art

[0002] In industries such as ore-thermal smelting, power grids, and the chemical industry, reactive power demand is enormous. Traditional electronically controlled compensation devices utilize a step-by-step adjustment method, resulting in slow response times and difficulty achieving ideal compensation results. Furthermore, frequent tap changer operation can easily degrade transformer oil due to arcing, requiring extensive maintenance. While magnetically controlled dynamic compensation devices offer high compensation accuracy, they also come at the expense of significant investment. In these situations, a magnetic-pressure hybrid dynamic reactive compensation device can significantly meet reactive power demand, combining the advantages of both electronically controlled and magnetically controlled dynamic compensation devices with a more cost-effective approach.

[0003] At present, when performing reactive power compensation through a magnetic-pressure hybrid dynamic reactive compensation device, a single control method is often used in related technologies. However, this method often uses real-time data feedback control when hybrid controlling two compensation methods, lacks the ability to predict load changes, and does not take into account the different applicable situations between the electric control compensation device and the magnetic control compensation device. If the compensation amount is adjusted, if the control interval is too long, it will also affect the compensation effect. Summary of the Invention

[0004] In order to solve the technical problems that a single control mode technology lacks the ability to predict load changes and does not take into account the applicability of electric control compensation devices and magnetic control compensation devices, thereby affecting the compensation effect, the present invention provides a fast response control method for a magnetic-pressure hybrid control type dynamic reactive power compensation device. The technical solution adopted is as follows: The present invention proposes a fast response control method for a magnetic-pressure hybrid-controlled dynamic reactive power compensation device, which includes a magnetic control compensation device and an electric control compensation device. The method includes: Collecting power data of the grid load in real time to generate a power data sequence, wherein the power data includes at least power factor, active power and reactive power in an uncompensated state; Based on the historical power data sequence, predict the power data sequence of the load in the future preset period and the predicted compensation amount at each moment in the future; At each future moment, based on the predicted active power and power factor, determine the compensation value range required to increase the power factor to the preset target power factor range; determine the basic compensation amount based on the overall fluctuation characteristics of the predicted active power sequence and reactive power sequence and the quantitative deviation between each predicted compensation amount and its compensation value range at the same moment; A sliding preset time window is set within a preset future period, and the magnetic control compensation weight at each moment is determined based on the deviation characteristics of the active power sequence and the reactive power sequence within the time window and the instantaneous change rate of the power change curve constructed by integrating the active and reactive power sequences; The basic compensation amount is divided into a magnetic control compensation amount and an electric control compensation amount according to the magnetic control compensation weight, and the magnetic control compensation device and the electric control compensation device are cooperatively controlled to output the compensation amount at the corresponding time.

[0005] Furthermore, the power factor includes an original power factor in an uncompensated state and an expected target power factor after compensation. The predicted compensation amount determination process includes: For each moment in a preset future period, based on the predicted active power, original power factor and target power factor, a predicted compensation amount is obtained through a preset compensation amount calculation function.

[0006] Furthermore, the compensation value interval determination process includes: For each moment in a preset future time period, based on the active power predicted at that moment and the upper limit of the preset target power factor range, the corresponding first target reactive power is reversely derived; based on the active power predicted at that moment and the lower limit of the preset target power factor range, the corresponding second target reactive power is reversely derived; Calculate the difference between the first target reactive power and the predicted reactive power in the uncompensated state at that moment as the upper limit value of the compensation amount range; The difference between the second target reactive power and the predicted reactive power in the uncompensated state at that moment is calculated as the lower limit value of the compensation amount range.

[0007] Furthermore, the power factor is calculated based on the reactive power and the active power.

[0008] Furthermore, the process of determining the overall fluctuation characteristics of the predicted active power sequence and reactive power sequence includes: In a preset future period, the predicted reactive power series and active power series are respectively subjected to STL decomposition processing to obtain decomposition data corresponding to each series, wherein the decomposition data includes a trend term, a seasonal term, and a residual term; The residual items corresponding to each future moment in the decomposed data are quantified as instantaneous fluctuation quantities for characterizing the degree of fluctuation of the power data at each moment.

[0009] Furthermore, the process of determining the degree of quantitative deviation between each predicted compensation amount and the corresponding compensation amount value interval includes: For each moment in the future preset period, the deviation between the predicted compensation amount and the compensation amount value interval at the same moment is calculated. The deviation is used to quantify the degree of deviation of each predicted compensation amount relative to its corresponding compensation amount value interval.

[0010] Furthermore, the calculation method of the deviation includes: If the predicted compensation amount is within the compensation amount value range at the same time, the deviation is 0; If the predicted compensation amount is less than the lower boundary value of the compensation amount value interval at the same time, the deviation is the difference between the lower boundary value and the predicted compensation amount; If the predicted compensation amount is greater than the upper boundary value of the compensation amount value interval at the same time, the deviation is the difference between the predicted compensation amount and the upper boundary value.

[0011] Furthermore, the basic compensation amount determination process includes: For each future moment, calculate the product of the inverse of the instantaneous fluctuation amount at the same moment and the deviation; performing a summation operation on all the products within a future preset time period to obtain a first summation value; Performing an exponential operation with a natural constant as a base and the opposite of the first sum value as an exponent to obtain an exponential function value; The product of the exponential function value and the predicted compensation amount at each future moment is calculated as the first compensation amount at each moment; the weighted average of the first compensation amount at each moment in the future preset time period is calculated as the basic compensation amount.

[0012] Furthermore, the magnetron compensation weight determination process includes: For each time window, calculating a first difference between the active power at each moment in the time window and the average of all active powers; calculating a second difference between the reactive power at each moment in the time window and the average of all reactive powers; Calculating the sum of the first difference and the second difference as a total difference; calculating the product of the total difference and the reciprocal of the instantaneous fluctuation amount; summing all of the products within the time window to obtain a power data fluctuation amount used to characterize the stability of the power data within the time window; and using the power data fluctuation amount as a fluctuation index at each moment within the corresponding time window; Calculate the slope of the power change curve constructed by integrating the active power sequence and the reactive power sequence at each moment; Based on the product of the inverse of the fluctuation index and the inverse of the absolute value of the slope at the same moment, the magnetic control compensation weight at each moment in the time window is obtained by a preset magnetic control compensation weight calculation function.

[0013] Furthermore, a fast response control method for a magnetic-pressure hybrid control type dynamic reactive power compensation device further includes: Collect the actual required compensation amount after compensation in real time; calculate the normalized deviation between the actual required compensation amount and the basic compensation amount; The magnetron compensation weight is controlled to decrease as the deviation increases, and the compensation amount resulting from the reduction of the magnetron compensation weight is automatically transferred to the electric control compensation branch.

[0014] The present invention has the following beneficial effects: The present invention first predicts the load power data sequence and the predicted compensation amount at each future moment based on the historical power data sequence, so as to cope with the sudden changes that the load may encounter and avoid the voltage flicker caused by the compensation decision lag of the magnetic-pressure hybrid control type dynamic reactive compensation device; then, through the compensation amount value range, the possible changes in the reactive compensation amount at each moment are predicted, and then the most reasonable basic compensation amount is analyzed, firstly, to avoid the subsequent electric control compensation device outputting too much compensation, which affects the stability of the power grid, and secondly, it can also suppress the harmonic resonance of the magnetic control compensation device; finally, through the appropriate magnetic control compensation weight, on the basis of the basic compensation amount, the compensation amount output by the electric control compensation device and the compensation amount output by the magnetic control compensation device are scientifically allocated, which greatly improves the reactive compensation effect of the magnetic-pressure hybrid control type dynamic reactive compensation device. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 A flow chart of a fast response control method for a magnetic-pressure hybrid-controlled dynamic reactive power compensation device provided by one embodiment of the present invention; Figure 2 This is a diagram illustrating the structure of a collection component of a magnetic-pressure hybrid-controlled dynamic reactive power compensation device provided by one embodiment of the present invention; Figure 3 This is an example diagram of the basic compensation amount determination process provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0017] To further illustrate the technical means and effectiveness of the present invention in achieving its intended objectives, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effectiveness of a rapid response control method for a magnetic-pressure hybrid-controlled dynamic reactive power compensation device proposed in accordance with the present invention. In the following description, references to different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0018] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0019] The specific scheme of the fast response control method of the magnetic-pressure hybrid control type dynamic reactive power compensation device provided by the present invention is described in detail below with reference to the accompanying drawings.

[0020] See also Figure 1 , which shows a flow chart of a fast response control method for a magnetic-pressure hybrid-controlled dynamic reactive power compensation device provided by one embodiment of the present invention, the method comprising: S101: Collect power data of the grid load in real time to generate a power data sequence, wherein the power data at least includes power factor, active power, and reactive power in an uncompensated state.

[0021] It can be understood that the magnetic-pressure hybrid control type dynamic reactive power compensation device includes a magnetic control compensation device and an electric control compensation device.

[0022] For example, the structure of the acquisition component of the magnetic-pressure hybrid dynamic reactive compensation device is shown in the figure below: Figure 2 As shown, the acquisition component is used to collect grid load power data. The device includes pre-set current sensors and voltage sensors, and real-time grid load voltage and current. The magnetic-pressure hybrid dynamic reactive compensation device also includes other common acquisition components, such as amplifiers, etc. The specific function introduction and connection method are common technical means, which will not be repeated in this embodiment. Normally, the voltage and current are synchronously collected at a preset sampling frequency through current sensors and voltage sensors, and the collected current and voltage data are then denoised and smoothed. The existing algorithm is used to calculate reactive power and power factor, and then the active power is determined based on the power factor, current and voltage through the existing calculation formula.

[0023] It should be noted that the methods for determining the power factor, active power and reactive power in an uncompensated state are all technical means well known to those skilled in the art and will not be described in detail in this embodiment.

[0024] It should be noted that the specific value of the preset sampling frequency is determined according to actual needs and is not specifically limited in this embodiment. For example, the preset sampling frequency may be 1 kHz (ie, 1000 samples per second).

[0025] It should be noted that since the compensated reactive power has been regulated, it cannot reflect the reactive characteristics of the load itself, and the uncompensated reactive power can truly reflect the original reactive demand of the load. Therefore, when predicting the reactive compensation amount at each moment in the future, the reactive power in the uncompensated state should be selected.

[0026] S102: Based on the historical power data sequence, predict the power data sequence of the load in a future preset time period and the predicted compensation amount at each moment in the future.

[0027] It should be noted that the existing time series prediction algorithm can be used to predict the power data sequence of the load within a preset time period in the future based on the historical power data sequence. For example, ARIMA (Autoregressive Integrated Moving Average) can be used to capture the dynamic laws of power data, thereby predicting the power data sequence. The specific method of predicting the power data sequence is a technical means well known to those skilled in the art and will not be repeated in this embodiment.

[0028] The specific value of the future preset time period is determined according to actual needs and is not specifically limited in this embodiment. For example, the power data sequence of the load within the next 5 minutes is predicted.

[0029] It should be noted that the power factor includes the original power factor in an uncompensated state and the expected target power factor after compensation.

[0030] The original power factor, the power factor before compensation, can usually be read by an energy meter or power factor meter.

[0031] The target power factor is the power factor that is expected to be achieved after compensation. Based on prior knowledge, the power factor specified by the country is usually in the range of 0.9~0.95.

[0032] In this embodiment, the predicted compensation amount can be obtained based on the predicted power data sequence. As a possible implementation method, for each moment in the future preset time period, the predicted compensation amount is obtained through a preset compensation amount calculation function based on the predicted active power, original power factor and target power factor.

[0033] It should be noted that the preset compensation amount calculation function is a common existing technical means and will not be described in detail in this embodiment. For example, the preset compensation amount calculation function can be expressed as: ,in, represents the predicted compensation amount; Indicates active power; Indicates the tangent value corresponding to the original power factor; Indicates the tangent value corresponding to the target power factor.

[0034] The power data sequence includes a power factor sequence, an active power sequence, and a reactive power sequence in an uncompensated state. The power factor sequence is composed of power factors arranged in chronological order; the active power sequence is composed of active power arranged in chronological order; and the reactive power sequence is composed of reactive power in an uncompensated state arranged in chronological order.

[0035] S103: For each future moment, based on the predicted active power and power factor, determine the compensation value range required to increase the power factor to the preset target power factor range; determine the basic compensation amount based on the overall fluctuation characteristics of the predicted active power sequence and reactive power sequence and the quantitative deviation degree between each predicted compensation amount and the compensation value range at the same moment.

[0036] It's important to understand that the fundamental purpose of a magnetic-pressure hybrid dynamic reactive power compensation device when performing dynamic reactive power compensation is to improve the power factor. Power factor deviations are used to determine whether reactive power compensation needs to be increased or decreased. The goal is to maintain the power factor within a reasonable range. Reactive power is the most direct compensation target. The magnetic-pressure hybrid dynamic reactive power compensation device adjusts its reactive compensation amount by analyzing reactive power changes in real time.

[0037] It should be noted that the power factor can be obtained based on the ratio of apparent power to active power. According to existing empirical knowledge, apparent power, active power, and reactive power satisfy the Pythagorean theorem. Based on active power and reactive power, the Pythagorean theorem can be used to obtain apparent power, and thus it can be deduced that the power factor can be calculated based on reactive power and active power. The power factor can be expressed by the following formula: , ,in, Indicates power factor; S indicates apparent power; represents active power; Q represents reactive power.

[0038] It should be noted that under actual working conditions, when the grid load is operating normally, the active power cannot be zero.

[0039] It should be noted that, from the calculation formula of power factor, it can be seen that when active power and power factor are known, reactive power can be reversely deduced.

[0040] It should be noted that in order to maintain the power factor in the future within a reasonable range, the reactive compensation amount, that is, the range of compensation requirement change, can be reversely deduced by analyzing the required range of power factor change.

[0041] In this embodiment, for each moment within a preset time period in the future, the corresponding first target reactive power is reversely derived based on the active power predicted at that moment and the upper limit value of the preset target power factor range; the corresponding second target reactive power is reversely derived based on the active power predicted at that moment and the lower limit value of the preset target power factor range; the difference between the first target reactive power and the predicted reactive power in the uncompensated state at that moment is calculated as the upper limit value of the compensation amount range; the difference between the second target reactive power and the predicted reactive power in the uncompensated state at that moment is calculated as the lower limit value of the compensation amount range.

[0042] It should be noted that the specific value range of the preset target power factor range is determined according to actual needs, and this embodiment does not make any specific limitations. For example, the value range of the preset target power factor range can be 0.9~0.95, which is in line with the national standards, wherein 0.9 is the lower limit of the preset target power factor range, and 0.95 is the upper limit of the preset target power factor range.

[0043] It is important to understand that when the grid voltage fluctuates, the magnetic-pressure hybrid dynamic reactive power compensation device will dynamically adjust the reactive power to ensure voltage stability. Excessively low or high voltage will affect equipment operation and power quality. It is known that changes in the voltage in the grid are affected by the load. Therefore, when the load power data changes, it will cause fluctuations in the grid voltage. The loads connected to the grid are generally large, such as factory equipment and grid parallel connection. Therefore, loads with large power fluctuations have a more obvious impact on the grid. Generally speaking, when the voltage is too high, reactive power compensation is reduced to keep the power factor within a reasonable range, and the voltage is reduced to a stable range. When the current is too large, reactive power compensation is usually increased to keep the power factor within a reasonable range.

[0044] It should be noted that when the connected load current increases, it is necessary to decide whether to increase or decrease reactive compensation based on the specific cause of the current increase (whether it is dominated by inductive reactive power or active power). The core logic is to optimize the current by adjusting reactive power, reduce line losses and maintain system stability. If the current increase is caused by excessive inductive reactive power, the reactive compensation amount is increased; if the current increase is caused by "increased active power", there is no need to adjust the reactive compensation (or fine-tune to maintain voltage stability). When the current increases, it is prioritized to determine whether it is caused by excessive inductive reactive power. The specific judgment method is a technical means well known to those skilled in the art and will not be described in detail in this embodiment.

[0045] The process of determining the basic compensation amount is as follows: Figure 3 Shown, including: S103-1: Within a preset future time period, perform STL decomposition processing on the predicted reactive power sequence and active power sequence respectively to obtain decomposition data corresponding to each sequence, where the decomposition data includes a trend term, a seasonal term, and a residual term.

[0046] It should be noted that the STL decomposition process is a seasonal-trend decomposition method based on local weighted regression. The trend term reflects the long-term change law of the corresponding sequence, the seasonal term reflects the periodic fluctuation characteristics of the corresponding sequence, and the residual term reflects the random fluctuation component of the corresponding sequence after removing the trend term and seasonal term.

[0047] Seasonal-Trend decomposition using LOESS (STL) based on local weighted regression is an existing decomposition technology for time series data. Therefore, the specific method of obtaining the decomposed data is a technical means well known to those skilled in the art and will not be described in detail in this embodiment.

[0048] S103-2: Quantify the residual items corresponding to each future moment in the decomposed data as the instantaneous fluctuation amount used to characterize the degree of fluctuation of the power data at each moment.

[0049] Among them, it should be noted that the specific method of quantitatively decomposing the residual terms corresponding to each future moment in the data is an existing technical means. For example, first, in order to eliminate the magnitude differences of the residual terms at different moments, the residual terms are normalized, and then, considering that the residual terms at different moments have different degrees of influence on the stability assessment of power data, the normalized residual terms are assigned weight coefficients. The weight coefficients can be dynamically adjusted according to factors such as data reliability and historical fluctuations, and finally the quantified residual terms are determined.

[0050] It's important to understand that in the STL process, two residual terms are generated after decomposing the active power and reactive power series separately (reflecting random fluctuations in active and reactive power that cannot be explained by the trend and periodic terms, respectively). To quantify these two residual terms into a unified "instantaneous fluctuation quantity," the core logic is to integrate the fluctuation characteristics of both to comprehensively reflect the overall stability of the power system.

[0051] As a possible implementation method, the two residual terms are first quantified separately, and the quantized values ​​of the two residuals are integrated into a comprehensive indicator through weighted or combined operations. For example, the instantaneous fluctuation amount can be obtained by taking the average after normalization.

[0052] It's important to understand that the larger the instantaneous fluctuation, or the quantified residual term, the more drastic the power data fluctuations at that moment, and the lower the data stability. The quantified residual term provides an accurate basis for subsequently determining parameters such as the basic compensation amount and the magnetic control compensation weight. The value of the instantaneous fluctuation is negatively correlated with system stability: smaller instantaneous fluctuations indicate weaker random fluctuations in active and reactive power, and more stable system operation. Larger instantaneous fluctuations indicate stronger random interference reflected by the residual term, and poorer system stability, requiring compensation strategies (such as adjusting magnetic control / electric control weights) to suppress fluctuations.

[0053] S103-3: For each moment in the future preset period, calculate the deviation between the predicted compensation amount and the compensation amount value interval at the same moment. The deviation is used to quantify the degree of deviation of each predicted compensation amount relative to its corresponding compensation amount value interval.

[0054] In this embodiment, if the predicted compensation amount is within the compensation amount value range at the same moment, the deviation is 0; if the predicted compensation amount is less than the lower boundary value of the compensation amount value range at the same moment, the deviation is the difference between the lower boundary value and the predicted compensation amount; if the predicted compensation amount is greater than the upper boundary value of the compensation amount value range at the same moment, the deviation is the difference between the predicted compensation amount and the upper boundary value.

[0055] S103-4: For each future moment, calculate the product of the inverse of the instantaneous fluctuation amount and the deviation at the same moment; sum all products within the future preset time period to obtain a first sum value; perform an exponential operation with a natural constant as the base and the opposite of the first sum value as the exponent to obtain an exponential function value.

[0056] Among them, it should be noted that, from the perspective of equipment safety: prevent the compensation amount from exceeding the rated capacity of the device (such as the maximum adjustment range of the magnetic control / electric control device); from the perspective of grid stability: avoid excessive compensation that leads to excessive power factor or voltage fluctuations, and ensure that the compensation is within a safe range. When determining a reasonable basic compensation amount, it is necessary not only to consider the situation where the adjustment of the magnetic control is maintained within a certain stable range, but also to consider the ability of the electric control compensation device to respond quickly when the power changes greatly. Therefore, the long-term change pattern of the reactive power sequence and the active power sequence in the preset time period in the future can be analyzed to explore the appropriate reactive compensation amount, that is, the basic compensation amount.

[0057] The exponential function value is a dimensionless safety adjustment factor generated, which is used to perform global attenuation control on the predicted compensation amount according to the real-time risk level of the power grid to obtain a more appropriate compensation amount at each moment. It integrates two types of key parameters: one is the instantaneous fluctuation amount, which is used to take into account the transient stability of the power grid; the other is the deviation degree, which is used to address the limitations of single indicator regulation.

[0058] Since the exponential function establishes a nonlinear attenuation relationship, if there are large instantaneous fluctuations in a certain future period, the quantitative result of the residual term (instantaneous fluctuation) reflects the randomness and severity of the power fluctuations. When the instantaneous fluctuation value is large (severe fluctuation), it indicates that the system is facing a strong random disturbance. In this case, the dynamic response weight of the basic compensation amount needs to be increased. By increasing the adjustment amplitude and speed of the compensation amount, the impact of the fluctuation on the power grid can be offset. Conversely, when the instantaneous fluctuation is small (fluctuation is gentle), the adjustment intensity of the compensation amount can be appropriately reduced to reduce the number of device operations and reduce energy consumption. Moreover, if the deviation is large, it indicates that the predicted compensation amount deviates further from the target range. In this case, the basic compensation amount needs to be adjusted to bring the compensation amount closer to a reasonable range. That is, when the fluctuation is gentle, the impact of the deviation is amplified (the compensation amount needs to be corrected to a reasonable range first), and when the fluctuation is severe, the impact of the deviation is weakened (to avoid excessive correction that exacerbates the fluctuation). In summary, the larger the first sum value, the smaller the exponential function value, which plays the role of "suppressing extreme value interference". Therefore, the exponential function value can be expressed by the following formula:

[0059] Where a represents the exponential function value; represents the instantaneous fluctuation at the i-th moment in the future preset time period; M represents the number of moments in the future preset time period; Indicates the deviation at the i-th moment in the future preset time period; Represents an exponential function with a natural constant as its base.

[0060] It should be noted that under actual working conditions, the quantified residual term, that is, the instantaneous fluctuation, is almost impossible to be zero in actual applications due to factors such as the inherent fluctuation of the power system, the limitations of the prediction model, the approximation of the quantification method and measurement errors. In other words, the instantaneous fluctuation cannot be zero.

[0061] For example, the future preset time period is within the next 30 seconds, 1 second is a moment, and there are 30 moments in the next 30 seconds, that is, M is 30.

[0062] S103-5: Calculate the product of the exponential function value and the predicted compensation amount at each future moment as the first compensation amount at each moment; calculate the weighted average of the first compensation amounts at each moment in the future preset time period as the basic compensation amount.

[0063] In order to ensure that the compensation strategy can cover the worst operating conditions (such as short-term strong fluctuations + large deviations from the range), avoid grid instability caused by insufficient compensation, and comply with the "safety first" principle of the power system, the weighted average of the first compensation amount at each moment in the future preset time period is calculated as the basic compensation amount.

[0064] It should be noted that weights can be dynamically assigned based on instantaneous fluctuations. The core logic of weight assignment is: the more severe the grid fluctuation, the higher the weight corresponding to the first compensation amount. Specifically, dynamic adjustments are made based on the two key indicators described in the document: "instantaneous fluctuation" and "deviation." For example, instantaneous fluctuation is used as the core weight factor. Instantaneous fluctuation is the quantified residual term obtained through STL decomposition, reflecting the degree of random fluctuation in active and reactive power at that moment (larger values ​​indicate more severe fluctuations). The weight is positively correlated with instantaneous fluctuation: larger instantaneous fluctuations at a given moment indicate poor grid stability, prioritizing compensation accuracy at that moment, thus assigning it a higher weight. Deviation is used as a correction factor. Deviation reflects the degree of deviation between the predicted compensation amount at that moment and the reasonable range (upper and lower bounds) (larger values ​​indicate greater deviation). If the deviation at a given moment is large, even if the instantaneous fluctuation is small, its weight should be appropriately increased to ensure that the compensation amount is corrected to the reasonable range. Weights at all moments are normalized to ensure that the sum of all weights is 1, avoiding distortion of the total compensation amount due to weight assignment.

[0065] It should be noted that the specific method of calculating the weight based on the two weight factors is a technical means well known to those skilled in the art and will not be repeated in this embodiment. For example, the weight is obtained by factor analysis.

[0066] S104: A sliding preset time window is set within a preset time period in the future, and the magnetic control compensation weight at each moment is determined based on the deviation characteristics of the active power sequence and the reactive power sequence within the time window and the instantaneous change rate of the power change curve constructed by integrating the active and reactive power sequences.

[0067] It's important to understand that the reactive power compensation output by a hybrid magnetic-pressure dynamic reactive power compensation device is equal to the sum of the magnetic control compensation output by the magnetic control device and the electric control compensation output by the electric control device. Magnetic control and electric control each perform different compensation functions: Magnetic control typically adjusts the inductive reactance or magnetic field strength of an inductor and is suitable for relatively stable load changes or long-term compensation. Electric control, by rapidly switching the operating state of capacitors or reactors, can more accurately respond to load fluctuations and rapid voltage changes and is suitable for short-term dynamic compensation. Magnetic control provides stable, long-term reactive power regulation, while electric control responds to transient fluctuations and offers a rapid response. This combination of the two ensures precise regulation during slow load changes through magnetic control, while rapid compensation is achieved through electric control during drastic load fluctuations. Electric control devices offer extremely fast response and rapid reactive power adjustment, while magnetic control provides relatively stable compensation without excessive fluctuations. This combination effectively addresses various dynamic and steady-state requirements of the power grid. Therefore, to determine an appropriate basic compensation amount, further categorization of the basic compensation amount is necessary.

[0068] In this embodiment, for each time window, the first difference between the active power at each moment in the time window and the average of all active powers is calculated; the second difference between the reactive power at each moment in the time window and the average of all reactive powers is calculated; the sum of the first difference and the second difference is calculated as the total difference; the product of the total difference and the inverse of the instantaneous fluctuation amount is calculated; all products in the time window are summed to obtain the power data fluctuation amount used to characterize the stability of the power data in the time window; and the power data fluctuation amount is used as the fluctuation index at each moment in the corresponding time window; the slope of the power change curve constructed by integrating the active power sequence and the reactive power sequence at each moment is calculated; based on the product between the inverse of the fluctuation index at the same moment and the inverse of the absolute value of the slope, the magnetic control compensation weight at each moment in the time window is obtained by presetting the magnetic control compensation weight calculation function.

[0069] Among them, it should be noted that the specific information of the preset time window can be determined according to actual needs, and this embodiment does not make specific limitations. For example, the future preset time period is the next 30 seconds. In order to be able to fully understand the fluctuations of the active power sequence and the reactive power sequence in the future preset time period, the preset time window can be a sliding time window with a fixed length of 3 seconds.

[0070] It should be noted that the specific construction method of the power change curve constructed by integrating the active power sequence and the reactive power sequence is a technical means well known to those skilled in the art, and will not be described in detail in this embodiment. For example, first, the time axis of the active power sequence and the reactive power sequence in the uncompensated state is calibrated to ensure that each data point of the two sequences corresponds to each other in time and eliminates time deviation; based on the existing power system formula, such as , , through the power system formula, the two characteristic quantities of active power and reactive power are integrated to reflect the comprehensive relationship between active and reactive power; finally, a single curve is drawn with time as the horizontal axis and apparent power or power factor as the vertical axis; or the active power curve and reactive power curve are drawn separately in the same coordinate system, and the coordinated change law of the two is displayed by superposition.

[0071] Because, if the difference between the reactive power and the mean of all reactive powers at a certain moment is large, and the difference between the active power and the mean of all active powers is also large, it reflects that the deviation of the load power from the average level in the window is more serious, indicating that the power fluctuation at that moment is more severe; through the product operation, the power deviation degree is combined with the instantaneous fluctuation. If the sum of the first difference and the second difference at a certain moment, that is, the total difference is larger and the instantaneous fluctuation is smaller (the inverse is larger), the product is larger and the contribution to the total fluctuation is higher; the sum operation aggregates the fluctuation characteristics of a single moment into the fluctuation degree of the window as a whole The greater the fluctuation, the more unstable the power data in the window is. In this window, rapid electronic compensation is required. At this moment, the compensation output by the electronic compensation device needs to be increased on the basis of the basic compensation. In this case, the magnetic compensation weight should be smaller. If the absolute value of the slope is larger, it reflects the changing trend of the power data, indicating that the rate of change of the power data at this moment is faster, and a faster compensation response is required later. In this case, the compensation output by the electronic compensation device can be increased, and the magnetic compensation weight should be smaller. Therefore, the magnetic compensation weight can be expressed by the following preset magnetic compensation weight calculation function:

[0072] in, represents the magnetic control compensation weight at the i-th moment in the future preset time period; ;in, It represents the volatility index at the i-th moment in the future preset time period; It represents the instantaneous fluctuation at the Zth moment in any time window; Represents the active power at the Zth moment in any time window; express The mean value of all active powers within the time window; Represents the reactive power at the Zth moment in any time window; express The mean value of all reactive powers within the time window; represents the slope at the i-th moment in the future preset time period; | | represents the absolute value; N represents the number of moments in any time window.

[0073] It should be noted that in the denominator as well as Add a very small positive offset to , mathematically ensuring that the denominator as well as Strictly greater than zero, thus completely eliminating the possibility of the denominator being zero in the division operation, ensuring the robustness and executable nature of the calculation formula, and It is preset to a sufficiently small positive value, and the principle for selecting its specific value is: as well as Under normal operating conditions, it is significantly greater than zero. The calculation results The effect of can be neglected, for example, The specific value of is determined according to actual needs. It can be 0.01, which is not specifically limited in this embodiment.

[0074] It should be noted that under actual working conditions, the quantified residual term, i.e., the instantaneous fluctuation, is almost impossible to be zero in actual applications due to factors such as the inherent fluctuation of the power system, the limitations of the prediction model, the approximation of the quantification method, and the measurement error. It can't be zero.

[0075] It should be noted that the sum of the magnetic control compensation weight and the electric control compensation weight is 1 (ie, the electric control compensation weight = 1 - magnetic control compensation weight).

[0076] S105: dividing the basic compensation amount into a magnetic control compensation amount and an electric control compensation amount according to the magnetic control compensation weight, and collaboratively controlling the magnetic control compensation device and the electric control compensation device to output the compensation amount at corresponding moments.

[0077] In this embodiment, the product of the basic compensation amount and the magnetron compensation weight is calculated as the magnetron compensation amount; and the difference between the basic compensation amount and the magnetron compensation amount is calculated as the electric control compensation amount.

[0078] It should be understood that the above analysis is quantified based on the collected predicted power data. However, in the case of reactive power compensation, there may be a certain deviation between the actual collected power data and the predicted value. When performing electronic control compensation, the response is faster, so the compensation amount can be adjusted directly according to the actual collected power data.

[0079] In this embodiment, the actual required compensation amount after compensation is collected in real time; the normalized deviation between the actual required compensation amount and the basic compensation amount is calculated; the magnetic control compensation weight is controlled to decrease as the deviation increases, and the compensation amount with the reduced magnetic control compensation weight is automatically transferred to the electronically controlled compensation branch.

[0080] Normalizing the deviation, normalizing the deviation between the actual required compensation amount and the basic compensation amount at the same moment. The specific calculation method of the deviation can refer to the explanation of step S103 of this embodiment, and will not be repeated in this embodiment.

[0081] It should be noted that the sum of the corrected magnetic control compensation amount and the electric control compensation amount remains consistent with the basic compensation amount, and the corrected electric control compensation amount does not exceed its maximum adjustment range, and the corrected magnetic control compensation amount does not exceed its rated compensation capacity.

[0082] It should be noted that the specific information of the maximum adjustment range and the rated compensation capacity is determined based on prior knowledge and is not specifically limited in this embodiment. For example, the maximum adjustment range may be 999 kvar, and the rated compensation capacity may be 2400 kvar.

[0083] It should be noted that the order in which the embodiments of the present invention are described above is for illustrative purposes only and does not necessarily represent the superiority or inferiority of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0084] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

Claims

1. A fast response control method for a magnetic-pressure hybrid control type dynamic reactive power compensation device, characterized in that: The device includes a magnetic control compensation device and an electric control compensation device, and the method includes: Collecting power data of the grid load in real time to generate a power data sequence, wherein the power data includes at least power factor, active power and reactive power in an uncompensated state; Based on the historical power data sequence, predict the power data sequence of the load in the future preset period and the predicted compensation amount at each moment in the future; At each future moment, based on the predicted active power and power factor, determine the compensation value range required to increase the power factor to the preset target power factor range; determine the basic compensation amount based on the overall fluctuation characteristics of the predicted active power sequence and reactive power sequence and the quantitative deviation between each predicted compensation amount and its compensation value range at the same moment; A sliding preset time window is set within a preset future period, and the magnetic control compensation weight at each moment is determined based on the deviation characteristics of the active power sequence and the reactive power sequence within the time window and the instantaneous change rate of the power change curve constructed by integrating the active and reactive power sequences; The basic compensation amount is divided into a magnetic control compensation amount and an electric control compensation amount according to the magnetic control compensation weight, and the magnetic control compensation device and the electric control compensation device are cooperatively controlled to output the compensation amount at the corresponding time.

2. The fast response control method of a magnetic-pressure hybrid control type dynamic reactive power compensation device according to claim 1, characterized in that: The power factor includes the original power factor in the uncompensated state and the target power factor expected after compensation. The process of determining the predicted compensation amount includes: For each moment in a preset future period, based on the predicted active power, original power factor and target power factor, a predicted compensation amount is obtained through a preset compensation amount calculation function.

3. The fast response control method of a magnetic-pressure hybrid control type dynamic reactive power compensation device according to claim 2, characterized in that: The compensation value interval determination process includes: For each moment in a preset future time period, based on the active power predicted at that moment and the upper limit of the preset target power factor range, the corresponding first target reactive power is reversely derived; based on the active power predicted at that moment and the lower limit of the preset target power factor range, the corresponding second target reactive power is reversely derived; Calculate the difference between the first target reactive power and the predicted reactive power in the uncompensated state at that moment as the upper limit value of the compensation amount range; The difference between the second target reactive power and the predicted reactive power in the uncompensated state at that moment is calculated as the lower limit value of the compensation amount range.

4. The fast response control method of a magnetic-pressure hybrid control type dynamic reactive power compensation device according to claim 3, characterized in that: The power factor is calculated based on reactive power and active power.

5. The fast response control method of a magnetic-pressure hybrid control type dynamic reactive power compensation device according to claim 1, characterized in that: The process of determining the overall fluctuation characteristics of the predicted active power sequence and reactive power sequence includes: In a preset future period, the predicted reactive power series and active power series are respectively subjected to STL decomposition processing to obtain decomposition data corresponding to each series, wherein the decomposition data includes a trend term, a seasonal term, and a residual term; The residual items corresponding to each future moment in the decomposed data are quantified as instantaneous fluctuation quantities for characterizing the degree of fluctuation of the power data at each moment.

6. The fast response control method of a magnetic-pressure hybrid control type dynamic reactive power compensation device according to claim 5, characterized in that: The process of determining the degree of quantitative deviation between each predicted compensation amount and the corresponding compensation amount value interval includes: For each moment in the future preset period, the deviation between the predicted compensation amount and the compensation amount value interval at the same moment is calculated. The deviation is used to quantify the degree of deviation of each predicted compensation amount relative to its corresponding compensation amount value interval.

7. The fast response control method of a magnetic-pressure hybrid control type dynamic reactive power compensation device according to claim 6, characterized in that: The calculation method of the deviation includes: If the predicted compensation amount is within the compensation amount value range at the same time, the deviation is 0; If the predicted compensation amount is less than the lower boundary value of the compensation amount value interval at the same time, the deviation is the difference between the lower boundary value and the predicted compensation amount; If the predicted compensation amount is greater than the upper boundary value of the compensation amount value interval at the same time, the deviation is the difference between the predicted compensation amount and the upper boundary value.

8. The fast response control method of a magnetic-pressure hybrid control type dynamic reactive power compensation device according to claim 7, characterized in that: The basic compensation amount determination process includes: For each future moment, calculate the product of the inverse of the instantaneous fluctuation amount at the same moment and the deviation; performing a summation operation on all the products within a future preset time period to obtain a first summation value; Performing an exponential operation with a natural constant as a base and the opposite of the first sum value as an exponent to obtain an exponential function value; The product of the exponential function value and the predicted compensation amount at each future moment is calculated as the first compensation amount at each moment; the weighted average of the first compensation amount at each moment in the future preset time period is calculated as the basic compensation amount.

9. The fast response control method of a magnetic-pressure hybrid control type dynamic reactive power compensation device according to claim 5, characterized in that: The magnetron compensation weight determination process includes: For each time window, calculating a first difference between the active power at each moment in the time window and the average of all active powers; calculating a second difference between the reactive power at each moment in the time window and the average of all reactive powers; Calculating the sum of the first difference and the second difference as a total difference; calculating the product of the total difference and the reciprocal of the instantaneous fluctuation amount; summing all of the products within the time window to obtain a power data fluctuation amount used to characterize the stability of the power data within the time window; and using the power data fluctuation amount as a fluctuation index at each moment within the corresponding time window; Calculate the slope of the power change curve constructed by integrating the active power sequence and the reactive power sequence at each moment; Based on the product of the inverse of the fluctuation index and the inverse of the absolute value of the slope at the same moment, the magnetic control compensation weight at each moment in the time window is obtained by a preset magnetic control compensation weight calculation function.

10. The fast response control method of a magnetic-pressure hybrid control type dynamic reactive power compensation device according to claim 1, characterized in that: The method further comprises: Collect the actual required compensation amount after compensation in real time; calculate the normalized deviation between the actual required compensation amount and the basic compensation amount; The magnetron compensation weight is controlled to decrease as the deviation increases, and the compensation amount resulting from the reduction of the magnetron compensation weight is automatically transferred to the electric control compensation branch.

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