Real-time coordination control method for multi-type voltage regulation equipment of active power distribution network

Abstract

The invention relates to a real-time coordination control method for multi-type voltage regulating equipment of an active power distribution network, which comprises the following steps of: 1, acquiring data through a phasor measurement unit (PMU) or a monitoring and data acquisition unit (SCADA), selecting a window period based on the acquired data, estimating voltage according to line-to-line voltage sensitivity, and calculating a voltage-to-line ratio of the voltage-to-line ratio of the voltage-to-line ratio of the voltage-to-line ratio of the voltage-to-line ratio of the voltage-to-line ratio; according to the charging and discharging equation of the battery energy storage, the battery charge capacity (SOC) is predicted; 2, smoothing and correcting the voltage based on bandwidth limitation of an on-load voltage regulator (OLTC) and power deviation of distributed new energy (DG), and constructing constraint conditions based on the distributed new energy and a battery energy storage system (BESS); and 3, in order to avoid early exhaustion of the battery energy storage system, adjusting the active power of the battery energy storage system according to the difference between the battery charge capacity and the battery reference charge capacity. The method can solve the problem that the mechanical pressure regulating device and the energy storage device interfere with each other during operation.

Description

Technical Field

[0001] The present invention belongs to the technical field of voltage control of distribution networks, and in particular relates to a real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network. Background Art

[0002] With the continuous growth of global energy consumption, the demand for new energy is also increasing. As an important part of the development of new energy, distributed new energy equipment has the advantages of wide distribution, small scale and environmental protection. However, the output of distributed new energy equipment is random and uncertain due to the influence of external environmental factors, resulting in voltage fluctuations with short duration and large fluctuations. The voltage can be adjusted by using traditional equipment. Mechanical voltage regulation is generally on-load voltage regulation and switchable capacitor banks. However, traditional mechanical voltage regulation equipment has the problems of slow response and long action time, which makes them difficult to track dynamically and adjust quickly. This is not flexible enough when facing frequent voltage fluctuations in the power grid or fine adjustment is required.

[0003] Compared with traditional mechanical voltage regulation equipment, continuous voltage regulation equipment such as energy storage that relies on converter grid connection has dynamic voltage regulation capability. Energy storage equipment has a faster response time and can adjust voltage more promptly to cope with changes in the power grid. Energy storage equipment has strong dynamic voltage fluctuation tracking capabilities and fine voltage regulation granularity, which can effectively manage voltage problems caused by large-scale access to distributed renewable energy. Due to the differences in action response time and regulation granularity between the two types of voltage regulation equipment, how to coordinate the operation of the two, avoid mutual interference between the two, and jointly participate in the voltage management of the active distribution network is an urgent problem to be solved. Summary of the invention

[0004] The object of the present invention is to provide a real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network, so as to solve the problem of mutual interference between mechanical voltage regulating equipment and energy storage equipment during operation.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: a real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network, comprising:

[0006] Step 1: Obtain data through a phasor measurement unit (PMU) or a supervisory control and data acquisition unit (SCADA), select a window period based on the acquired data, estimate the voltage based on the line voltage sensitivity, and predict the battery state of charge (SOC) based on the battery energy storage charge and discharge equation;

[0007] Step 2: Smooth and correct the voltage based on the bandwidth limitation of the on-load voltage regulator (OLTC) and the power deviation of the distributed renewable energy (DG), and construct constraints based on the distributed renewable energy and battery energy storage system (BESS);

[0008] Step 3: To avoid early exhaustion of the battery energy storage system, the active power of the battery energy storage system is adjusted according to the difference between the battery charge and the battery reference charge.

[0009] Furthermore, in step 1, the distributed renewable energy system monitors and controls the active distribution network by PMU and SCADA. The PMU obtains relevant data by being installed on the battery energy storage system, and the SCADA collects real-time information on the rapid changes in the power system caused by the integration of different power electronic devices and renewable energy sources;

[0010] By analyzing the power fluctuations of distributed renewable energy in different periods, a period lasting 10 seconds is selected as the window period;

[0011] The method for estimating the voltage is:

[0012] Measure the distributed renewable energy power values ​​at time t, t+2 and t+4 respectively, and substitute them into formula (1) to obtain the predicted value of distributed renewable energy power at time t+10;

[0013]

[0014] In the formula, is the predicted value of the distributed renewable energy power at the end of the period, P DG (t), P DG (t+2) and P DG (t+4) are the measured values ​​of the distributed renewable energy power at t, t+2 and t+4 respectively; in each control cycle, the voltage deviation ΔV caused by the introduction of distributed renewable energy into the system DG as follows:

[0015]

[0016] In the formula, is the line-to-line voltage sensitivity relative to the active power at the point of common coupling;

[0017] The method for predicting SOC based on the charge and discharge equation of battery energy storage is:

[0018]

[0019] Where, SOC(t+10) pred represents the predicted SOC of BESS, SOC(t) is the SOC at the beginning of the control cycle, ΔP b is the power required by the BESS, is the nominal voltage of BESS, C b is the rated capacity of the BESS.

[0020] Furthermore, in step 2, the method for smoothing and modifying the voltage is:

[0021] According to the voltage sensitivity and voltage deviation, the voltage is smoothed and limited within the set range, taking into account the voltage deviation ΔV caused by the distributed new energy system DG , the objective function of voltage deviation caused by the introduction of distributed renewable energy generation is obtained; the details are as follows:

[0022]

[0023] In the formula, and are the average line voltage sensitivity coefficients relative to active power and reactive power, respectively; ΔP B , ΔQ B and ΔQ DG They are the active and reactive deviations of BESS and the reactive deviation of distributed renewable energy.

[0024] Furthermore, the correction process of the voltage deviation is:

[0025] If the voltage exceeds the set range, the voltage is adjusted to ensure that the voltage regulation provided by BESS and distributed renewable energy can keep the voltage outside the dead zone of OLTC;

[0026]

[0027] In the formula, is the corrected voltage deviation, V ref is the reference voltage, ΔP DG is the power deviation of the distributed new energy inverter, V PCC is the measured common point voltage, V db is the dead-time voltage of OLTC, [], ||, β, V min and V max They represent the maximum integer function, absolute value function, correction factor, minimum voltage and maximum voltage limits of voltage setting respectively; β is 10% of the upper or lower voltage limit;

[0028] When the predicted voltage deviation at time t is greater than V max When the voltage deviation is adjusted to β outside the OLTC dead zone, the tap change signal of the OLTC remains continuous and the time delay T D The OLTC then changes its taps; through this voltage correction process, the voltage violation is corrected so that the voltage is always kept within the appropriate range, thereby improving the system's resistance to interference.

[0029] Furthermore, in step 2, the constraints based on the distributed renewable energy and battery energy storage system include ramp rate limitation, power limitation, SOC limitation and power factor limitation.

[0030] Furthermore, the ramp rate is limited as follows:

[0031]

[0032]

[0033] In the formula, are the maximum changes of active and reactive power of BESS, is the maximum reactive power change of photovoltaic.

[0034] Furthermore, the power limits are as follows:

[0035]

[0036] In the formula, Indicates the maximum power that BESS can provide, P BZ It represents the sum of the active power and active power deviation of BESS.

[0037] Furthermore, the SOC limits are as follows:

[0038] SOC min ≤SOC(t+10) pred ≤SOC max (11)

[0039] In the formula, SOC min is the minimum value that SOC can reach, SOC max It is the maximum value that SOC can reach.

[0040] Furthermore, the power factor is limited as follows:

[0041]

[0042] In the formula, PF B and COSψ DG are the power factors of BESS and distributed renewable energy inverters; Q BZ is the sum of the reactive power and reactive power deviation of BESS, P DGZ is the sum of the active power and active power deviation of distributed renewable energy, Q DGZ It is the sum of the reactive power and reactive deviation of distributed renewable energy.

[0043] Furthermore, in step 3, the early exhaustion problem of BESS is:

[0044] When dealing with voltage fluctuations at the PCC, the priority is to stabilize the voltage through reactive power compensation; the BESS is able to provide reactive power in this process to balance the grid demand, thereby mitigating voltage fluctuations; this also indirectly puts the BESS into a dormant state, as the BESS will only be awakened and put into operation when the required reactive power exceeds the reserve;

[0045] However, if there are long-term voltage fluctuations and the BESS is frequently required to provide reactive power, this will cause the BESS to be exhausted prematurely, thus affecting the availability of the BESS in possible emergency situations in the future. In order to avoid the early exhaustion of the BESS, ΔP B Modified to And according to Searching for the next best value and To make SOC close to its reference level SOC ref ;

[0046] The SOC adjustment method of BESS is:

[0047] 1) Charging process

[0048] When the BESS is charging, ΔP B The best obtained value of is negative in the control loop; by modifying ΔP B The value of SOC is close to SOC ref ; If the current SOC is greater than its reference SOC value, the charging power is reduced to avoid the problem of early exhaustion of BESS;

[0049] If the SOC value is less than the reference value, increase ΔP B , to approach its reference value; when SOC is equal to SOC max hour, tends to zero; the specific formula is as follows:

[0050]

[0051] In the formula, SOC ref For reference SOC; is the optimal active power change of BESS;

[0052] 2) Discharge process

[0053] The same as the charging process:

[0054]

[0055] In the formula, and current SOC and SOC ref The distance between them is directly proportional;

[0056] 3) SOC adjustment method

[0057] Prioritize voltage fluctuation events. If the voltage exceeds the specified range, the SOC adjustment method will not be executed. Instead, the voltage violation event will be treated as a priority, and the system will transfer the required active power elsewhere to avoid the voltage continuing to exceed the specified range.

[0058] The SOC adjustment formula is as follows:

[0059]

[0060] In the formula, is the active power required by the optimized BESS.

[0061] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network. The method reduces mutual interference between devices by coordinating the operation of distributed new energy inverters, BESS and traditional OLTC, improves the ability to deal with voltage violations, improves the anti-interference ability of the system, and greatly reduces BESS, bringing economic benefits. In addition, through the coordinated operation between devices, compared with the traditional control scheme, the OLTC tap operation is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 is a flow chart of a real-time coordinated control method for multiple types of voltage regulating equipment in an active power distribution network according to an embodiment of the present invention;

[0063] Figure 2 It is a principle block diagram of the implementation of the real-time coordinated control method of multiple types of voltage regulating equipment in an active distribution network according to an embodiment of the present invention;

[0064] Figure 3 is the window period selected by the embodiment of the present invention. DETAILED DESCRIPTION

[0065] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0066] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0067] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0068] like Figure 1 , 2 As shown, this embodiment provides a real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network, including the following steps.

[0069] Step 1: Obtain data through a phasor measurement unit (PMU) or a supervisory control and data acquisition unit (SCADA), select a window period based on the acquired data, estimate the voltage based on the line voltage sensitivity, and predict the battery state of charge (SOC) based on the battery energy storage charge and discharge equation.

[0070] Specifically, the distributed renewable energy system monitors and controls the active distribution network through PMU and SCADA. PMU obtains relevant data by installing on the battery energy storage system, and SCADA collects real-time information on the rapid changes in the power system caused by the integration of different power electronic devices and renewable energy. For example, PMU sensors can collect DG , Q DG , P B , Q B 、V PCC And data required by SOC, etc.

[0071] The power of distributed renewable energy will change frequently, which will affect the change of voltage. However, the power change of the distributed renewable energy system is predictable because it shows a linear relationship during the small cycle window. The power change can be observed by selecting a suitable window period, and the power and SOC can be predicted. By analyzing the power fluctuations of distributed renewable energy in different periods, a period of 10s is selected as the window period. The window period selected in this embodiment is as follows: Figure 3 shown.

[0072] The method for estimating the voltage is:

[0073] The values ​​of distributed renewable energy power at time t, t+2 and t+4 are measured respectively, and substituted into equation (1) to obtain the predicted value of distributed renewable energy power at time t+10;

[0074]

[0075] In the formula, is the predicted value of the distributed renewable energy power at the end of the period, P DG (t), P DG (t+2) and P DG (t+4) are the measured values ​​of distributed renewable energy power at time t, t+2 and t+4 respectively.

[0076] In each control cycle, the voltage deviation ΔV caused by the introduction of distributed renewable energy into the system DG as follows:

[0077]

[0078] In the formula, is the line-to-line voltage sensitivity relative to the active power at the point of common coupling.

[0079] The method for predicting SOC based on the charge and discharge equation of battery energy storage is:

[0080]

[0081] Where, SOC(t+10) pred represents the predicted SOC of BESS, SOC(t) is the SOC at the beginning of the control cycle, ΔP b is the power required by the BESS, is the nominal voltage of BESS, C b is the rated capacity of the BESS.

[0082] Step 2: Smooth and correct the voltage based on the bandwidth limitation of the on-load voltage regulator (OLTC) and the power deviation of the distributed renewable energy (DG), and construct constraints based on the distributed renewable energy and battery energy storage system (BESS).

[0083] The specific method for smoothing and modifying the voltage is:

[0084] According to the voltage sensitivity and voltage deviation, the voltage is smoothed and limited within the set range, taking into account the voltage deviation ΔV caused by the distributed new energy system DG , the objective function of voltage deviation caused by the introduction of distributed renewable energy generation is obtained; the details are as follows:

[0085]

[0086] In the formula, and are the average line voltage sensitivity coefficients relative to active power and reactive power, respectively; ΔP B , ΔQ B and ΔQ DG They are the active and reactive deviations of BESS and the reactive deviation of distributed renewable energy.

[0087] The correction process of voltage deviation is:

[0088] If the voltage exceeds the set range, the voltage is adjusted to ensure that the voltage regulation provided by the BESS and distributed renewable energy can keep the voltage outside the OLTC dead zone. This maintains the continuity of the OLTC tap signal and keeps the OLTC in the voltage regulation loop. When the OLTC changes its tap, the power consumed by the BESS is adjusted accordingly after the OLTC waiting period, which helps ensure that the BESS is available in future emergencies.

[0089]

[0090] In the formula, is the corrected voltage deviation, V ref is the reference voltage, ΔP DG is the power deviation of the distributed new energy inverter, V PCC is the measured common point voltage, V db is the dead-time voltage of OLTC, [], ||, β, V min and V max They represent the maximum integer function, absolute value function, correction factor, minimum voltage and maximum voltage limits of voltage setting respectively; β is 10% of the upper or lower voltage limit.

[0091] Specifically, when the predicted voltage deviation at time t is greater than V max When the voltage deviation is adjusted to β outside the OLTC dead zone, the tap change signal of the OLTC remains continuous and the time delay T D The OLTC then changes its taps. Through this voltage correction process, voltage violations are corrected so that the voltage is always kept within the appropriate range, improving the system's resistance to disturbances.

[0092] Based on the constraints of distributed renewable energy and battery energy storage systems, including ramp rate limit, power limit, SOC limit and power factor limit optimization limit.

[0093] Among them, the ramp rate limits are as follows:

[0094]

[0095] In the formula, are the maximum changes of active and reactive power of BESS, is the maximum reactive power change of photovoltaic. Generally speaking, the slope rate of distributed new energy inverters and BESS inverters ranges from a few percentages to a few thousandths. 1 , X 2 and X 3The value range may be 1-2% of the change in active power and reactive power per second.

[0096] During discharge or charging, whether it is active power or reactive power, the maximum power value provided by the BESS should be subject to the maximum power limit of the BESS itself. The power limit is as follows:

[0097]

[0098] In the formula, Indicates the maximum power that BESS can provide, P BZ It represents the sum of the active power and active power deviation of BESS.

[0099] For the protection of BESS, some restrictions on SOC are needed to prevent over-discharge or over-charge of BESS. The SOC restriction conditions are as follows:

[0100] SOC min ≤SOC(t+10) pred ≤SOC max (11)

[0101] In the formula, SOC min is the minimum value that SOC can reach, SOC max It is the maximum value that SOC can reach.

[0102] The power factor limits are as follows:

[0103]

[0104] In the formula, PF B and COSψ DG are the power factors of BESS and distributed renewable energy inverters; Q BZ is the sum of the reactive power and reactive power deviation of BESS, P DGZ is the sum of the active power and active power deviation of distributed renewable energy, Q DGZ It is the sum of the reactive power and reactive deviation of distributed renewable energy. θ takes values ​​between 0.95 and 1, while η takes values ​​between 0.8 and 1.

[0105] Step 3: To avoid early exhaustion of the battery energy storage system, the active power of the battery energy storage system is adjusted according to the difference between the battery charge and the battery reference charge.

[0106] The early exhaustion problem of BESS is that when dealing with voltage fluctuations at the PCC, the priority is to stabilize the voltage through reactive power compensation. BESS can provide reactive power in this process to balance the demand of the grid, thereby alleviating voltage fluctuations. This also indirectly causes BESS to enter a dormant state, because BESS will only be awakened and put into operation when the required reactive power exceeds the reserve.

[0107] However, if there are long-term voltage fluctuations and the BESS is frequently required to provide reactive power, this may cause premature exhaustion of the BESS. This may affect the availability of the BESS in possible emergency situations in the future. To avoid early exhaustion of the BESS, ΔP B Modified to And according to Searching for the next best value and To make SOC close to its reference level SOC ref .

[0108] The SOC adjustment method of BESS is:

[0109] 1) Charging process

[0110] When the BESS is charging, ΔP B The best obtained value of is negative in the control loop; by modifying ΔP B The value of SOC is close to SOC ref ; If the current SOC is greater than its reference SOC value, the charging power is reduced to avoid early exhaustion of the BESS.

[0111] If the SOC value is less than the reference value, increase ΔP B , to approach its reference value; when SOC is equal to SOC max hour, tends to zero; the specific formula is as follows:

[0112]

[0113] In the formula, SOC ref is the reference SOC; ΔP B r is the optimal active power change of BESS.

[0114] 2) Discharge process

[0115] The same as the charging process:

[0116]

[0117] In the formula, and current SOC and SOC refThe distance between them is directly proportional.

[0118] 3) SOC adjustment method

[0119] The SOC adjustment method will give priority to voltage fluctuation events. If the voltage exceeds the specified range, the SOC adjustment method will not be executed. Instead, the voltage violation event will be treated as a priority, and the system will transfer the required active power elsewhere to avoid the voltage continuing to exceed the specified range.

[0120] The SOC adjustment formula is as follows:

[0121]

[0122] In the formula, is the active power required by the optimized BESS.

[0123] The present invention provides a real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network, which uses real-time phasor measurement unit (PMU) data to coordinate on-load voltage regulator (OLTC), battery energy storage system (BESS) and distributed new energy inverter for optimal control. First, the data is measured by the phasor measurement unit (PMU) and the supervisory control and data acquisition (SCADA), and then the window period is selected, and the voltage and SOC are predicted at the same time, and the voltage correction operation is performed. Then, the key values ​​such as SOC and power are constrained. Finally, in order to avoid early exhaustion of BESS, the active power of the battery energy storage system is adjusted according to the distance between the battery charge and the battery reference charge, which enables the SOC to recover to the reference level faster to cope with the upcoming emergency. The present invention solves the problem of fast-changing and slow-changing voltages introduced by distributed new energy systems and loads, reduces the problem of mutual interference between devices, and solves the problem of early exhaustion of BESS.

[0124] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0125] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0126] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0127] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0128] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network, characterized in that: include: Step 1: Obtain data through a phasor measurement unit (PMU) or a supervisory control and data acquisition unit (SCADA), select a window period based on the acquired data, estimate the voltage based on the line voltage sensitivity, and predict the battery state of charge (SOC) based on the battery energy storage charge and discharge equation; Step 2: Smooth and correct the voltage based on the bandwidth limitation of the on-load voltage regulator (OLTC) and the power deviation of the distributed renewable energy (DG), and construct constraints based on the distributed renewable energy and battery energy storage system (BESS); Step 3: To avoid early exhaustion of the battery energy storage system, the active power of the battery energy storage system is adjusted according to the difference between the battery charge and the battery reference charge.

2. The method for real-time coordinated control of multiple types of voltage regulating equipment in an active distribution network according to claim 1, characterized in that: In step 1, the distributed renewable energy system monitors and controls the active distribution network by PMU and SCADA. PMU obtains relevant data by being installed on the battery energy storage system, and SCADA collects real-time information on the rapid changes in the power system caused by the integration of different power electronic devices and renewable energy sources. By analyzing the power fluctuations of distributed renewable energy in different periods, a period lasting 10 seconds is selected as the window period; The method for estimating the voltage is: Measure the distributed renewable energy power values ​​at time t, t+2 and t+4 respectively, and substitute them into formula (1) to obtain the predicted value of distributed renewable energy power at time t+10; In the formula, is the predicted value of the distributed renewable energy power at the end of the period, P DG (t), P DG (t+2) and P DG (t+4) are the measured values ​​of the distributed renewable energy power at time t, t+2 and t+4 respectively; in each control cycle, the voltage deviation ΔV caused by the introduction of distributed renewable energy into the system DG as follows: In the formula, is the line-to-line voltage sensitivity relative to the active power at the point of common coupling; The method for predicting SOC based on the charge and discharge equation of battery energy storage is: Where, SOC(t+10) pred represents the predicted SOC of BESS, SOC(t) is the SOC at the beginning of the control cycle, ΔP b is the power required by the BESS, is the nominal voltage of BESS, C b is the rated capacity of the BESS.

3. The method for real-time coordinated control of multiple types of voltage regulating equipment in an active distribution network according to claim 1, characterized in that: In step 2, the method for smoothing and modifying the voltage is: According to the voltage sensitivity and voltage deviation, the voltage is smoothed and limited within the set range, taking into account the voltage deviation ΔV caused by the distributed new energy system DG , the objective function of voltage deviation caused by the introduction of distributed renewable energy generation is obtained; the details are as follows: In the formula, and are the average line voltage sensitivity coefficients relative to active power and reactive power, respectively; ΔP B , ΔQ B and ΔQ DG They are the active and reactive deviations of BESS and the reactive deviation of distributed renewable energy.

4. The method for real-time coordinated control of multiple types of voltage regulating equipment in an active distribution network according to claim 3 is characterized in that: The correction process of voltage deviation is: If the voltage exceeds the set range, the voltage is adjusted to ensure that the voltage regulation provided by BESS and distributed renewable energy can keep the voltage outside the dead zone of OLTC; In the formula, is the corrected voltage deviation, V ref is the reference voltage, ΔP DG is the power deviation of the distributed new energy inverter, V PCC is the measured common point voltage, V db is the dead-time voltage of OLTC, [], ||, β, V min and V max They represent the maximum integer function, absolute value function, correction factor, minimum voltage and maximum voltage limits of voltage setting respectively; β is 10% of the upper or lower voltage limit; When the predicted voltage deviation at time t is greater than V max When the voltage deviation is adjusted to β outside the OLTC dead zone, the tap change signal of the OLTC remains continuous and the time delay T D The OLTC then changes its taps; through this voltage correction process, the voltage violation is corrected so that the voltage is always kept within the appropriate range, thereby improving the system's resistance to interference.

5. The method for real-time coordinated control of multiple types of voltage regulating equipment in an active distribution network according to claim 3, characterized in that: In step 2, the constraints based on distributed renewable energy and battery energy storage systems include ramp rate limit, power limit, SOC limit and power factor limit.

6. A real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network according to claim 5, characterized in that: The ramp rate limits are as follows: In the formula, are the maximum changes of active and reactive power of BESS, is the maximum reactive power change of photovoltaic.

7. A real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network according to claim 5, characterized in that: The power limits are as follows: In the formula, Indicates the maximum power that BESS can provide, P BZ It represents the sum of the active power and active power deviation of BESS.

8. The real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network according to claim 5, characterized in that: The SOC limits are as follows: SOC min ≤SOC(t+10) pred ≤SOC max (11) In the formula, SOC min is the minimum value that SOC can reach, SOC max It is the maximum value that SOC can reach.

9. A real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network according to claim 5, characterized in that: The power factor limits are as follows: In the formula, PF B and COSψ DG are the power factors of BESS and distributed renewable energy inverters; Q BZ is the sum of the reactive power and reactive power deviation of BESS, P DGZ is the sum of the active power and active power deviation of distributed renewable energy, Q DGZ It is the sum of the reactive power and reactive deviation of distributed renewable energy.

10. A real-time coordinated control method for multiple types of voltage regulating equipment in an active distribution network according to claim 1, characterized in that: In step 3, the early exhaustion problem of BESS is: When dealing with voltage fluctuations at the PCC, the priority is to stabilize the voltage through reactive power compensation; the BESS is able to provide reactive power in this process to balance the grid demand, thereby mitigating voltage fluctuations; this also indirectly puts the BESS into a dormant state, as the BESS will only be awakened and put into operation when the required reactive power exceeds the reserve; However, if there are long-term voltage fluctuations and the BESS is frequently required to provide reactive power, this will cause the BESS to be exhausted prematurely, thus affecting the availability of the BESS in possible emergency situations in the future. In order to avoid the early exhaustion of the BESS, ΔP B Modified to And according to Searching for the next best value and To make SOC close to its reference level SOC ref ; The SOC adjustment method of BESS is: 1) Charging process When the BESS is charging, ΔP B The best obtained value of is negative in the control loop; by modifying ΔP B The value of SOC is close to SOC ref ; If the current SOC is greater than its reference SOC value, the charging power is reduced to avoid the problem of early exhaustion of BESS; If the SOC value is less than the reference value, increase ΔP B , to be close to its reference value; When SOC equals SOC max When ΔP B r tends to zero; the specific formula is as follows: In the formula, SOC ref For reference SOC; is the optimal active power change of BESS; 2) Discharge process The same as the charging process: In the formula, and current SOC and SOC ref The distance between them is directly proportional; 3) SOC adjustment method Prioritize voltage fluctuation events. If the voltage exceeds the specified range, the SOC adjustment method will not be executed. Instead, the voltage violation event will be treated as a priority, and the system will transfer the required active power elsewhere to avoid the voltage continuing to exceed the specified range. The SOC adjustment formula is as follows: In the formula, is the active power required by the optimized BESS.

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