A Multi-Source Coordinated Voltage Control Method and System for New Energy Power Plants

Abstract

This invention discloses a multi-source coordinated voltage control method and system for new energy power plants. The new energy power plant includes an SVG device, an energy storage device, and a new energy power generation device. The voltage control method includes the following steps: obtaining the PCC point voltage value of the new energy power plant; when the PCC point voltage value is lower than a preset voltage threshold, sequentially adjusting the output power of the SVG device, the energy storage device, and the new energy power generation device to bring the PCC point voltage value up to the preset voltage threshold. By performing multi-source coordinated voltage control on the new energy power plant, and sequentially adjusting the SVG device, the energy storage device, and the new energy power generation device, the PCC point voltage of the new energy power plant is precisely controlled. Based on the principle of optimal output and fully utilizing the reactive power regulation capabilities of each device, the system stability and adaptability are improved, ensuring the stable operation of the new energy power plant.

Description

Technical Field

[0001] This invention relates to the field of new energy power plant control technology, and in particular to a multi-source coordinated voltage control method and system for new energy power plants. Background Technology

[0002] The development of large-scale new energy bases has accelerated, and countries around the world are committed to developing new energy sources, represented by wind and solar power. However, the output of wind turbines and photovoltaic units is greatly affected by the weather, and their power generation is subject to large random fluctuations, which often leads to phenomena such as "wind curtailment" and "solar curtailment" on the power generation side.

[0003] Currently, photovoltaic (PV) power is mainly connected to the power system in two forms: large-capacity centralized connection and distributed connection. Centralized PV power is mainly connected to the high-voltage transmission network, while distributed PV power is mainly connected to the distribution network. However, due to the technical characteristics of distributed power generation, which differ from traditional energy generation methods, large-scale grid connection, while alleviating environmental pressure and creating economic benefits, will also increase the risks to the safe operation of the distribution network, posing new challenges to its safe operation. After the integration of distributed power, the distribution network structure will change from the traditional radial chain structure to a multi-source structure, thus altering the original power flow and voltage distribution of the distribution network. The intermittent and fluctuating output of distributed power may cause voltage fluctuations at various nodes of the distribution network, further complicating the control and operation of the distribution network.

[0004] Furthermore, with the large-scale integration of new energy systems, the short-circuit capacity of traditional power grids is continuously decreasing. Traditional power grids lack adequate voltage regulation methods, resulting in increasingly poor voltage control capabilities, which in turn leads to a decline in overall system voltage control. Currently, voltage support for new energy power plants mainly relies on SVG (Static Var Generator), but SVG has limited support capacity, especially during transient processes, where it can only support the voltage at the PCC (Pressure Capacity Center) point.

[0005] Reactive power and voltage control in large-scale renewable energy bases follows the principle of "layered and zoned, local balancing," coordinating various reactive power equipment within the base and fully utilizing the performance differences between these devices to control the voltage at each node within the region within a specified range, thus ensuring the safety of the regional power grid voltage. During power system operation, various inductive devices and transformers consume a significant amount of reactive power. Without control, this can lead to a decrease in the power factor of the power system, affecting its operational stability. Summary of the Invention

[0006] The purpose of this invention is to provide a multi-source coordinated voltage control method and system for new energy power plants. By performing multi-source coordinated voltage control on new energy power plants, the SVG equipment, energy storage device and new energy power generation device are adjusted sequentially to accurately regulate the PCC point voltage of the new energy power plant. Based on the principle of optimal output and giving full play to the reactive power regulation capabilities of each device, the system stability and adaptability are improved, and the stable operation of the new energy power plant is guaranteed.

[0007] To address the aforementioned technical problems, a first aspect of this invention provides a multi-source coordinated voltage control method for new energy power plants, wherein the new energy power plant includes: SVG equipment, energy storage device, and new energy power generation device, and the voltage control method includes the following steps:

[0008] Obtain the PCC point voltage value of the new energy power plant;

[0009] When the voltage value at the PCC point is lower than the preset voltage threshold, the output power of the SVG device, the energy storage device, and the new energy power generation device are adjusted in sequence to bring the voltage value at the PCC point up to the preset voltage threshold.

[0010] Furthermore, the step of sequentially adjusting the output power of the SVG device, the energy storage device, and the new energy power generation device includes:

[0011] The reactive power output of the SVG device is controlled to be at its maximum value. The first equivalent power output and the first target capacity output capacity of the new energy power plant are calculated. The first reactive power output value of the SVG device is determined based on the relationship between the first equivalent power output and the first target capacity output capacity.

[0012] If the first target capacity output capacity is greater than the first equivalent output power, the active power input value of the energy storage device is adjusted to the maximum value, and the second equivalent output power and the second target capacity output capacity of the new energy power plant are calculated again. The second active power output value of the energy storage device is determined according to the relationship between the second equivalent output power and the second target capacity output capacity.

[0013] If the second target capacity output capacity is greater than the second equivalent output power, the reactive power output value of the energy storage device is adjusted to the maximum value, and the third equivalent output power and the third target capacity output capacity of the new energy power plant are calculated again. The third reactive power output value of the energy storage device is determined based on the relationship between the third equivalent output power and the third target capacity output capacity.

[0014] If the third target capacity output capacity is greater than the third equivalent output power, the reactive power output value of the new energy power generation device is adjusted to the maximum value, and the fourth equivalent output power and the fourth target capacity output capacity of the new energy power plant are calculated again. The fourth reactive power output value of the new energy power generation device is determined based on the relationship between the fourth equivalent output power and the fourth target capacity output capacity.

[0015] Further, the reactive power output of the controlled SVG device is at its maximum value. The first equivalent power output and the first target capacity output of the new energy power plant are calculated. Based on the relationship between the first equivalent power output and the first target capacity output, the first reactive power output value of the SVG device is determined, including:

[0016] Adjust the reactive power output value of the SVG device to the maximum value to obtain the rated output capacity of the first AC system under the current state;

[0017] The capacity of the energy storage device and the state of several inverters in the new energy power generation device are kept constant, and the first equivalent output power of the new energy power plant is calculated.

[0018] Calculate the first target capacity output capacity based on the rated output capacity of the first AC system and the first equivalent output power.

[0019] When the first target capacity output capacity is less than the first equivalent output power, the reactive power output value of the SVG device is controlled to be the difference between the target capacity output capacity and the sum of the reactive power output values ​​of the energy storage device and the new energy power generation device.

[0020] When the first target capacity output capacity is greater than or equal to the first equivalent output power, the first reactive power output value of the SVG device is controlled to be the maximum value.

[0021] Further, the active power input value of the energy storage device is adjusted to its maximum value, and the second reactive power demand value and the second reactive power supply value of the new energy power plant are calculated again. Based on the relationship between the second reactive power demand value and the second reactive power supply value, the second active power output value of the energy storage device is determined, including:

[0022] Adjust the active power input value of the energy storage device to its maximum value to obtain the rated output capacity of the second AC system under the current state;

[0023] The states of several inverters in the SVG equipment and the new energy power generation device are kept unchanged, and the second equivalent output power of the new energy power plant is calculated.

[0024] Calculate the second target capacity output capacity based on the rated output capacity of the second AC system and the second equivalent output power.

[0025] When the second target capacity output capacity is less than the second equivalent output power, the reactive power absorption value of the energy storage device is controlled to be the difference between the target capacity output capacity and the output capacity of all other devices except the SVG device and the energy storage device.

[0026] When the second target capacity output capacity is greater than or equal to the second equivalent output power, the second active power output value of the energy storage device is controlled to be the maximum value.

[0027] Further, the reactive power output value of the energy storage device is adjusted to its maximum value, and the third equivalent power output and the third target capacity output capacity of the new energy power plant are calculated again. The third reactive power output value of the energy storage device is determined based on the relationship between the third equivalent power output and the third target capacity output capacity, including:

[0028] Adjust the reactive power output value of the energy storage device to the maximum value to obtain the rated output capacity of the third AC system under the current state;

[0029] The states of several inverters in the SVG device and the new energy power generation device are kept constant, and the active power output value of the energy storage device is kept constant. The third equivalent output power of the new energy power plant is calculated.

[0030] Calculate the third target capacity output capacity based on the rated output capacity of the third AC system and the third equivalent output power.

[0031] When the third target capacity output capacity is less than the third equivalent output power, the third reactive power output value of the energy storage device is controlled to be the difference between the target capacity output capacity and the sum of the reactive power output value of the SVG device, the active power output value of the energy storage device, and the output capacity of the new energy power generation device.

[0032] When the third target capacity output capacity is greater than or equal to the third equivalent output power, the third reactive power output value of the energy storage device is controlled to be the maximum value.

[0033] Further, the reactive power output value of the adjusted new energy power generation device is set to its maximum value, and the fourth equivalent output power and the fourth target capacity output capacity of the new energy power plant are calculated again. Based on the relationship between the fourth equivalent output power and the fourth target capacity output capacity, the fourth reactive power output value of the new energy power generation device is determined, including:

[0034] Adjust the reactive power output value of the new energy power generation device to the maximum value to obtain the rated output capacity of the fourth AC system under the current state;

[0035] By keeping the states of several inverters in the SVG device and the capacity of the energy storage device constant, the fourth equivalent output power of the new energy power plant is calculated.

[0036] Calculate the fourth target capacity output capacity based on the rated output capacity of the fourth AC system and the fourth equivalent output power.

[0037] When the fourth target capacity output capacity is less than the fourth equivalent output power, the fourth reactive power output value of the new energy power generation device is controlled to be the difference between the target capacity output capacity and the reactive power output value of the SVG device, the capacity of the energy storage device and the active power output value of the new energy power generation device.

[0038] When the target capacity output capacity is greater than or equal to the equivalent output power, the fourth reactive power output value of the new energy power generation device is controlled to be the maximum value.

[0039] Accordingly, a second aspect of the present invention provides a multi-source coordinated voltage control system for a new energy power plant, wherein the new energy power plant includes: SVG equipment, energy storage device, and new energy power generation device, and the voltage control system includes:

[0040] A voltage detection module is used to acquire the voltage value of the PCC point of the new energy power plant;

[0041] The power adjustment module is used to adjust the output power of the SVG device, the energy storage device and the new energy power generation device in sequence when the voltage value of the PCC point is lower than the preset voltage threshold, so that the voltage value of the PCC point reaches the preset voltage threshold.

[0042] Furthermore, the power adjustment module includes:

[0043] The SVG device adjustment unit is used to control the output reactive power of the SVG device to the maximum value, calculate the first equivalent power output and the first target capacity output capacity of the new energy power plant, and determine the first reactive power output value of the SVG device based on the relationship between the first equivalent power output and the first target capacity output capacity.

[0044] The first energy storage adjustment unit is used to adjust the active power input value of the energy storage device to the maximum value if the first target capacity output capacity is greater than the first equivalent output power, and to recalculate the second equivalent output power and the second target capacity output capacity of the new energy power plant, and determine the second active power output value of the energy storage device based on the relationship between the second equivalent output power and the second target capacity output capacity.

[0045] The second energy storage adjustment unit is used to adjust the reactive power output value of the energy storage device to the maximum value if the output capacity of the second target capacity is greater than the second equivalent output power, and to recalculate the third equivalent output power and the third target capacity output capacity of the new energy power plant, and determine the third reactive power output value of the energy storage device based on the relationship between the third equivalent output power and the third target capacity output capacity.

[0046] The new energy power generation adjustment unit is used to adjust the output reactive power of the new energy power generation device to the maximum value if the output capacity of the third target capacity is greater than the third equivalent output power, and to recalculate the fourth equivalent output power and the fourth target capacity output capacity of the new energy power plant. Based on the relationship between the fourth equivalent output power and the fourth target capacity output capacity, the fourth reactive power output value of the new energy power generation device is determined.

[0047] Accordingly, a third aspect of the present invention provides an electronic device, including: at least one processor; and a memory connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to cause the at least one processor to perform the above-described multi-source coordinated voltage control method for new energy power plants.

[0048] Accordingly, a fourth aspect of the present invention provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the above-described multi-source coordinated voltage control method for new energy power plants.

[0049] The above-described technical solutions of the embodiments of the present invention have the following beneficial technical effects:

[0050] 1. By integrating SVG equipment, energy storage devices, and new energy power generation devices for coordinated control, there are clear steps and judgment criteria for adjusting the output power of each device, which realizes the fine regulation of the voltage of new energy power plants. Each device plays a role at different stages, cooperates with each other, and dynamically adjusts the output according to the actual needs of the system, thereby improving the flexibility and effectiveness of voltage control.

[0051] 2. SVG equipment can quickly adjust reactive power, energy storage devices have flexible active and reactive power adjustment capabilities, and new energy power generation devices can also provide reactive power support. By adjusting each device in sequence, we can give full play to their advantages in reactive and active power adjustment, ensure the stable operation of new energy power plants, and reduce the adverse effects of voltage fluctuations.

[0052] 3. Under different system conditions, determine the output values ​​of each device based on reasonable calculation methods. Adjust the device output flexibly according to the relationship between the target output capacity and the equivalent transmitted power, enabling the system to better adapt to different voltage variations and improving the stability and reliability of new energy power plants. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the topology of a new energy power plant provided in an embodiment of the present invention;

[0054] Figure 2 This is a flowchart of the multi-source coordinated voltage control method for new energy power plants provided in this embodiment of the invention;

[0055] Figure 3 This is a block diagram of the multi-source coordinated voltage control system module for new energy power plants provided in an embodiment of the present invention;

[0056] Figure 4 This is a block diagram of the power adjustment module provided in an embodiment of the present invention.

[0057] Figure label:

[0058] 1. Voltage detection module; 2. Power adjustment module; 21. SVG equipment adjustment unit; 22. First energy storage adjustment unit; 23. Second energy storage adjustment unit; 24. New energy power generation adjustment unit. Detailed Implementation

[0059] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0060] Please refer to Figure 1 and Figure 2 The first aspect of this invention provides a multi-source coordinated voltage control method for new energy power plants. The new energy power plant includes: SVG equipment, energy storage device, and new energy power generation device. The voltage control method includes the following steps:

[0061] Step S100: Obtain the voltage value of the PCC point of the new energy power plant.

[0062] By acquiring the PCC point voltage value of new energy power plants, the voltage status of the power plants can be monitored in real time. Once the PCC point voltage value is found to be lower than the preset voltage threshold, control measures can be quickly initiated to achieve a precise response.

[0063] Step S200: When the PCC point voltage value is lower than the preset voltage threshold, the output power of the SVG device, energy storage device and new energy power generation device are adjusted in sequence to increase the PCC point voltage value so that the PCC point voltage value reaches the preset voltage threshold.

[0064] By integrating and coordinating various types of equipment, such as SVG devices, energy storage devices, and new energy power generation devices, the SVG devices can quickly adjust reactive power output; the energy storage devices have flexible active and reactive power regulation capabilities; and the new energy power generation devices can also provide reactive power support to a certain extent. Each device works in concert, leveraging its own advantages to achieve synergy. By adjusting the output power of different devices sequentially, targeted regulation can be performed based on the characteristics and actual conditions of each device, improving the flexibility and effectiveness of voltage control.

[0065] Both new energy systems and energy storage systems possess a certain reactive power support capability. In new energy power plants, the reactive power capability of each device should be fully utilized to achieve comprehensive AC voltage regulation. Based on the reactive power support capability of new energy and energy storage systems, this capability should be fully utilized in the power plant to achieve comprehensive AC voltage regulation. This helps improve the stability and reliability of the power system and reduces the adverse effects of voltage fluctuations. By effectively controlling the voltage at the PCC point, the voltage value is kept at a preset voltage threshold, ensuring the stable operation of the new energy power plant, reducing the risk of equipment damage, and improving the overall safety and reliability of the power system.

[0066] like Figure 1 The diagram shows the basic structure of a new energy power plant, where the inverter can represent a photovoltaic inverter, a wind turbine inverter, an energy storage inverter, or an SVG inverter.

[0067] Let the active power of inverter n be P. n The reactive power is Q n The port voltage is U n The branch current is I n DC impedance is X n Then we have:

[0068]

[0069] Where α n Let n be the phase angle of the output voltage and current of inverter n.

[0070] Let the voltage at point PCC of the new energy power plant be U. pcc The equivalent voltage of the AC system is U s The system's equivalent impedance is X. s The equivalent current is I s Then we have:

[0071]

[0072] Where δ n Let be the phase angle of the voltage and equivalent current of the new energy power plant. j represents the imaginary part of the complex field.

[0073] The system equivalent current satisfies the following relationship:

[0074] I s =∑I n +I X (3)

[0075] Where I x It represents the equivalent current collected from other plants or AC systems.

[0076] From formula (2), when the power grid structure is fixed, the equivalent voltage U of the AC system is... s Equivalent impedance I s Neither will change, therefore the change in the voltage at point PCC is mainly due to I. s The changes are caused by I, and during the voltage regulation process of new energy power plants, n The changes will also cause I s The change in current leads to a change in coupled voltage. Considering that the reactive power of an AC system is mainly balanced locally, the equivalent model of the AC system mainly considers the reactive power consumption of active power transmission and equivalent impedance. Therefore, the voltage drop at the PCC point caused by the change in current can be expressed as follows:

[0077]

[0078] in S is the rate of change of AC voltage at point PCC caused by the change in capacitance. M S is the equivalent short-circuit capacity of the AC system. N S represents the rated output capacity of the near-cell AC system, and S represents the current equivalent output capacity of the AC system.

[0079] in

[0080] S = S P +S O (5)

[0081] Where S p For the equivalent output power of new energy power plants, S o For the equivalent capacity of other AC systems, when the equivalent capacity of other AC systems increases, S o An increase will cause a voltage drop.

[0082]

[0083] When the voltage drops, it can be increased by adjusting the output power, and the reactive power generated can be increased to compensate for the voltage drop. o Part of the reactive power is used to increase the voltage.

[0084] If we assume the minimum target value for voltage regulation is set to K... pcc Then the target capacity and output capacity are:

[0085]

[0086] Where K pcc Generally, it should not be less than 0.95.

[0087] Monitor the voltage at the PCC point; when the voltage at the PCC point is lower than K... pcc When the target capacity output capacity is reached, it is calculated according to equation (7):

[0088]

[0089] Where S p0 This is the original output capacity of the new energy power plant.

[0090] According to formula (6), the state of each inverter needs to be adjusted to satisfy formula (8).

[0091] There are clear steps and judgment criteria for adjusting the output power of each device, enabling precise control of the voltage in new energy power plants. By gradually adjusting the output power of different devices, the optimal combination that brings the PCC point voltage value to the preset voltage threshold can be found more accurately.

[0092] Specifically, step S200 involves sequentially adjusting the output power of the SVG device, energy storage device, and new energy power generation device, including the following steps:

[0093] Step S210: Control the output reactive power of the SVG device to the maximum value, calculate the first equivalent power output and the first target capacity output capacity of the new energy power plant, and determine the first reactive power output value of the SVG device based on the relationship between the first equivalent power output and the first target capacity output capacity.

[0094] Adjust the reactive power output of the SVG device to its maximum value, leveraging its ability to rapidly adjust reactive power and respond quickly to voltage changes. Calculate the first equivalent output power and the first target output capacity. Based on the relationship between these two values, determine the first reactive power output value of the SVG device, providing a basis for subsequent adjustments.

[0095] Step S220: If the first target capacity output capacity is greater than the first equivalent output power, the active power input value of the energy storage device is adjusted to the maximum value, and the second equivalent output power and the second target capacity output capacity of the new energy power plant are calculated again. The second active power output value of the energy storage device is determined based on the relationship between the second equivalent output power and the second target capacity output capacity.

[0096] If the first target capacity output capacity is greater than the first equivalent output power, then the active power input value of the energy storage device is adjusted to the maximum value. This step fully utilizes the active power regulation capability of the energy storage device, influencing the system state by absorbing active power, and then recalculates the second equivalent output power and the second target capacity output capacity to determine the second active power output value of the energy storage device.

[0097] In step S230, if the second target capacity output capacity is greater than the second equivalent power output, the reactive power output value of the energy storage device is adjusted to the maximum value, and the third equivalent power output and the third target capacity output capacity of the new energy power plant are calculated again. The third reactive power output value of the energy storage device is determined based on the relationship between the third equivalent power output and the third target capacity output capacity.

[0098] If the second target capacity output capacity is greater than the second equivalent output power, then the reactive power output value of the energy storage device is adjusted to its maximum value. To further explore the reactive power regulation potential of the energy storage device, the third equivalent output power and the third target capacity output capacity are recalculated to determine the third reactive power output value of the energy storage device.

[0099] In step S240, if the third target capacity output capacity is greater than the third equivalent output power, the reactive power output value of the new energy power generation device is adjusted to the maximum value, and the fourth equivalent output power and the fourth target capacity output capacity of the new energy power plant are calculated again. The fourth reactive power output value of the new energy power generation device is determined based on the relationship between the fourth equivalent output power and the fourth target capacity output capacity.

[0100] When the third target capacity output capacity is greater than the third equivalent output power, the reactive power output value of the new energy power generation device is finally adjusted to the maximum value. Utilizing the reactive power support capability of the new energy power generation device, the fourth equivalent output power and the fourth target capacity output capacity are recalculated to determine the fourth reactive power output value of the new energy power generation device.

[0101] Throughout the process, the SVG equipment, energy storage devices, and new energy power generation devices work sequentially and collaboratively to effectively control the voltage of the new energy power plant. The adjustment of each device is based on the adjustment results of the previous device and the actual needs of the system, ensuring the effectiveness and efficiency of multi-source coordination. This phased and targeted adjustment method better adapts to different voltage changes, improving the stability and reliability of the new energy power plant. When the voltage falls below the preset threshold, timely and effective measures can be taken to restore the PCC point voltage value to the preset voltage threshold, ensuring the normal operation of the power system.

[0102] Further, in step S210, the output reactive power of the SVG device is controlled to be at its maximum value. The first equivalent power output and the first target capacity output capacity of the new energy power plant are calculated. Based on the relationship between the first equivalent power output and the first target capacity output capacity, the first reactive power output value of the SVG device is determined, including:

[0103] Step S211: Adjust the reactive power output value of the SVG device to the maximum value and obtain the rated output capacity of the first AC system under the current state.

[0104] Step S212: Control the capacity of the energy storage device and the state of several inverters in the new energy power generation device to remain unchanged, and calculate the first equivalent output power of the new energy power plant.

[0105] By keeping the capacity of the energy storage device and the state of several inverters in the new energy power generation device constant, the first equivalent output power of the new energy power plant is calculated. This ensures that when analyzing the impact of the SVG device on the system, the interference caused by the state changes of other devices is eliminated, so that the calculation results more accurately reflect the role of the SVG device.

[0106] Step S213: Calculate the first target capacity output capacity based on the rated output capacity of the first AC system and the first equivalent output power.

[0107] Step S214: When the first target capacity output capacity is less than the first equivalent output power, the reactive power output value of the SVG device is controlled to be the difference between the target capacity output capacity and the sum of the reactive power output values ​​of the energy storage device and the new energy power generation device.

[0108] When the first target capacity output is less than the first equivalent output power, the reactive power output value of the controlled SVG device is the difference between the target capacity output and the sum of the reactive power output values ​​of the energy storage device and the new energy power generation device. This method of flexibly adjusting the reactive power output according to different situations ensures that the SVG device can play an optimal regulatory role under different system states, thereby improving the stability and reliability of the system.

[0109] Step S215: When the first target capacity output capacity is greater than or equal to the first equivalent output power, the first reactive power output value of the SVG device is controlled to be the maximum value.

[0110] When the first target capacity output capacity is greater than or equal to the first equivalent output power, the first reactive power output value of the SVG device is controlled to be at its maximum value, so as to make full use of the adjustment capability of the SVG device and quickly respond to the voltage change requirements of the system.

[0111] Throughout the process, the SVG equipment cooperated with energy storage devices and new energy power generation devices. By rationally adjusting the reactive power output of the SVG equipment, multi-source coordinated control was achieved, optimizing the system performance of the new energy power plant. Under different system states, the output of each device could be dynamically adjusted according to actual needs, improving the system's adaptability and stability.

[0112] Further, in step S220, the active power input value of the energy storage device is adjusted to its maximum value, and the second reactive power demand value and the second reactive power supply value of the new energy power plant are calculated again. Based on the relationship between the second reactive power demand value and the second reactive power supply value, the second active power output value of the energy storage device is determined, including:

[0113] Step S221: Adjust the active power input value of the energy storage device to the maximum value to obtain the rated output capacity of the second AC system under the current state.

[0114] By adjusting the active power input value of the energy storage device to its maximum value, the active power regulation capability of the energy storage device can be fully utilized, providing strong support for improving the voltage stability of new energy power plants.

[0115] Step S222: Control the states of several inverters in the SVG equipment and the new energy power generation device to remain unchanged, and calculate the second equivalent output power of the new energy power plant.

[0116] By keeping the states of several inverters in the SVG equipment and the new energy power generation device unchanged, the second equivalent output power of the new energy power plant is calculated. This method ensures that when analyzing the impact of the energy storage device on the system, the interference caused by the state changes of other equipment is eliminated, so that the calculation results more accurately reflect the role of the energy storage device.

[0117] Step S223: Calculate the second target capacity output capacity based on the rated output capacity of the second AC system and the second equivalent output power.

[0118] Step S224: When the second target capacity output capacity is less than the second equivalent output power, the reactive power absorption value of the energy storage device is controlled to be the difference between the target capacity output capacity and the output capacity of all other devices except the SVG device and the energy storage device.

[0119] When the second target capacity output is less than the second equivalent output power, the reactive power absorption value of the energy storage device is controlled as the difference between the target capacity output and the output capacity of all other devices except the SVG device and the energy storage device. This method of flexibly adjusting the reactive power absorption value according to different situations ensures that the energy storage device can play an optimal regulatory role under different system states, thereby improving the stability and reliability of the system.

[0120] Step S225: When the second target capacity output capacity is greater than or equal to the second equivalent output power, the second active power output value of the energy storage device is controlled to be the maximum value.

[0121] When the second target capacity output capacity is greater than or equal to the second equivalent output power, the second active power output value of the energy storage device is controlled to the maximum value, so as to make full use of the regulation capability of the energy storage device and quickly respond to the voltage change requirements of the system.

[0122] Throughout the process, the energy storage device, SVG equipment, and new energy power generation devices cooperated with each other. By rationally adjusting the active power output and reactive power absorption of the energy storage device, multi-source coordinated control was achieved, optimizing the system performance of the new energy power plant. Under different system states, the output of each device can be dynamically adjusted according to actual needs, improving the system's adaptability and stability.

[0123] Further, in step S230, the reactive power output value of the energy storage device is adjusted to its maximum value, and the third equivalent power output and the third target capacity output capacity of the new energy power plant are calculated again. Based on the relationship between the third equivalent power output and the third target capacity output capacity, the third reactive power output value of the energy storage device is determined, including:

[0124] Step S231: Adjust the reactive power output value of the energy storage device to the maximum value to obtain the rated output capacity of the third AC system under the current state.

[0125] By adjusting the reactive power output of the energy storage device to its maximum value, the reactive power regulation capability of the energy storage device can be fully utilized, thereby improving the voltage stability of new energy power plants.

[0126] Step S232: Control the states of several inverters in the SVG equipment and the new energy power generation device to remain unchanged, and control the active power output value of the control energy storage device to remain unchanged, and calculate the third equivalent power output of the new energy power plant.

[0127] By keeping the states of several inverters in the SVG equipment and the new energy power generation device constant, and keeping the active power output value of the energy storage device constant, the third equivalent power output of the new energy power plant is calculated. This method ensures that when analyzing the impact of the reactive power output of the energy storage device on the system, interference from changes in the state of other equipment is eliminated, making the calculation results more accurately reflect the role of the reactive power of the energy storage device.

[0128] Step S233: Calculate the third target capacity output capacity based on the rated output capacity of the third AC system and the third equivalent output power.

[0129] Step S234: When the third target capacity output capacity is less than the third equivalent output power, the third reactive power output value of the energy storage device is controlled to be the difference between the target capacity output capacity and the sum of the reactive power output value of the SVG device, the active power output value of the energy storage device, and the output capacity of the new energy power generation device.

[0130] When the third target capacity output capacity is less than the third equivalent output power, the third reactive power output value of the energy storage device is controlled as the difference between the target capacity output capacity and the sum of the reactive power output value of the SVG device, the active power output value of the energy storage device, and the output capacity of the new energy power generation device. This method of flexibly adjusting the reactive power output according to different situations ensures that the energy storage device can play an optimal regulatory role under different system states, thereby improving the stability and reliability of the system.

[0131] Step S235: When the third target capacity output capacity is greater than or equal to the third equivalent output power, the third reactive power output value of the energy storage device is controlled to be the maximum value.

[0132] When the third target capacity output capacity is greater than or equal to the third equivalent output power, the third reactive power output value of the energy storage device is controlled to the maximum value, so as to make full use of the regulation capability of the energy storage device and quickly respond to the voltage change requirements of the system.

[0133] Throughout the process, the energy storage device, SVG equipment, and new energy power generation device cooperated with each other. By reasonably adjusting the reactive power output of the energy storage device, multi-source coordinated control was achieved, and the system performance of the new energy power plant was optimized.

[0134] Further, in step S240, the reactive power output value of the new energy power generation device is adjusted to the maximum value, and the fourth equivalent output power and the fourth target capacity output capacity of the new energy power plant are calculated again. Based on the relationship between the fourth equivalent output power and the fourth target capacity output capacity, the fourth reactive power output value of the new energy power generation device is determined, including:

[0135] Step S241: Adjust the reactive power output value of the new energy power generation device to the maximum value, and obtain the rated output capacity of the fourth AC system under the current state.

[0136] Step S242: Control the states of several inverters and the capacity of energy storage devices in the SVG equipment to remain unchanged, and calculate the fourth equivalent power output of the new energy power plant.

[0137] By keeping the states of several inverters and the capacity of the energy storage device in the SVG equipment constant, the fourth equivalent output power of the new energy power plant is calculated. This method ensures that interference from changes in the states of other equipment is eliminated when analyzing the impact of reactive power output from new energy power generation devices on the system.

[0138] Step S243: Calculate the fourth target capacity output capacity based on the fourth AC system rated output capacity and the fourth equivalent output power.

[0139] Step S244: When the fourth target capacity output capacity is less than the fourth equivalent output power, the fourth reactive power output value of the new energy power generation device is controlled to be the difference between the target capacity output capacity and the sum of the reactive power output value of the SVG device, the energy storage device capacity, and the active power output value of the new energy power generation device.

[0140] When the fourth target capacity output capacity is less than the fourth equivalent output power, the fourth reactive power output value of the new energy power generation device is controlled to be the difference between the target capacity output capacity and the sum of the reactive power output value of the SVG device, the energy storage device capacity, and the active power output value of the new energy power generation device.

[0141] Step S245: When the target capacity output capacity is greater than or equal to the equivalent output power, the fourth reactive power output value of the new energy power generation device is controlled to be the maximum value.

[0142] When the target capacity output capacity is greater than or equal to the equivalent output power, the fourth reactive power output value of the new energy power generation device is controlled to the maximum value, so as to make full use of the regulation capability of the new energy power generation device and quickly respond to the voltage change requirements of the system.

[0143] By rationally adjusting the reactive power output of new energy power generation devices, multi-source coordinated control can be achieved, thereby optimizing the system performance of new energy power plants.

[0144] Accordingly, please refer to Figure 3 A second aspect of this invention provides a multi-source coordinated voltage control system for a new energy power plant. The new energy power plant includes: SVG equipment, energy storage devices, and new energy power generation devices. The voltage control system includes:

[0145] Voltage detection module 1 is used to acquire the voltage value of the PCC point in the new energy power plant.

[0146] The power adjustment module 2 is used to adjust the output power of the SVG device, energy storage device and new energy power generation device in sequence when the voltage value at the PCC point is lower than the preset voltage threshold, so that the voltage value at the PCC point reaches the preset voltage threshold.

[0147] Further, please refer to Figure 4 The power adjustment module 2 includes:

[0148] The SVG device adjustment unit 21 is used to control the output reactive power of the SVG device to the maximum value, calculate the first equivalent power output and the first target capacity output capacity of the new energy power plant, and determine the first reactive power output value of the SVG device based on the relationship between the first equivalent power output and the first target capacity output capacity.

[0149] The first energy storage adjustment unit 22 is used to adjust the active power input value of the energy storage device to the maximum value if the first target capacity output capacity is greater than the first equivalent output power, and to recalculate the second equivalent output power and the second target capacity output capacity of the new energy power plant, and determine the second active power output value of the energy storage device based on the relationship between the second equivalent output power and the second target capacity output capacity.

[0150] The second energy storage adjustment unit 23 is used to adjust the reactive power output value of the energy storage device to the maximum value if the output capacity of the second target capacity is greater than the second equivalent output power, and to recalculate the third equivalent output power and the third target capacity output capacity of the new energy power plant, and determine the third reactive power output value of the energy storage device based on the relationship between the third equivalent output power and the third target capacity output capacity.

[0151] The new energy power generation adjustment unit 24 is used to adjust the output reactive power of the new energy power generation device to the maximum value if the third target capacity output capacity is greater than the third equivalent output power, and to recalculate the fourth equivalent output power and the fourth target capacity output capacity of the new energy power plant. Based on the relationship between the fourth equivalent output power and the fourth target capacity output capacity, the fourth reactive power output value of the new energy power generation device is determined.

[0152] Accordingly, a third aspect of the present invention provides an electronic device, including: at least one processor; and a memory connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to cause the at least one processor to perform the above-described multi-source coordinated voltage control method for new energy power plants.

[0153] Accordingly, a fourth aspect of the present invention provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the above-described multi-source coordinated voltage control method for new energy power plants.

[0154] This invention aims to protect a multi-source coordinated voltage control method and system for new energy power plants. The new energy power plant includes an SVG device, an energy storage device, and a new energy power generation device. The voltage control method includes the following steps: obtaining the PCC point voltage value of the new energy power plant; when the PCC point voltage value is lower than a preset voltage threshold, sequentially adjusting the output power of the SVG device, the energy storage device, and the new energy power generation device to bring the PCC point voltage value up to the preset voltage threshold. The above technical solution has the following effects:

[0155] 1. By integrating SVG equipment, energy storage devices, and new energy power generation devices for coordinated control, there are clear steps and judgment criteria for adjusting the output power of each device, which realizes the fine regulation of the voltage of new energy power plants. Each device plays a role at different stages, cooperates with each other, and dynamically adjusts the output according to the actual needs of the system, thereby improving the flexibility and effectiveness of voltage control.

[0156] 2. SVG equipment can quickly adjust reactive power, energy storage devices have flexible active and reactive power adjustment capabilities, and new energy power generation devices can also provide reactive power support. By adjusting each device in sequence, we can give full play to their advantages in reactive and active power adjustment, ensure the stable operation of new energy power plants, and reduce the adverse effects of voltage fluctuations.

[0157] 3. Under different system conditions, determine the output values ​​of each device based on reasonable calculation methods. Adjust the device output flexibly according to the relationship between the target output capacity and the equivalent transmitted power, enabling the system to better adapt to different voltage variations and improving the stability and reliability of new energy power plants.

[0158] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0159] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0160] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0161] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0162] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A multi-source coordinated voltage control method for new energy power plants, characterized in that, The new energy power plant includes: SVG equipment, energy storage device, and new energy power generation device. The voltage control method includes the following steps: Obtain the PCC point voltage value of the new energy power plant; When the voltage value at the PCC point is lower than the preset voltage threshold, the output power of the SVG device, the energy storage device and the new energy power generation device are adjusted in sequence to make the voltage value at the PCC point reach the preset voltage threshold. The step of sequentially adjusting the output power of the SVG device, energy storage device, and new energy power generation device includes: The reactive power output of the SVG device is controlled to be at its maximum value. The first equivalent power output and the first target capacity output capacity of the new energy power plant are calculated. The first reactive power output value of the SVG device is determined based on the relationship between the first equivalent power output and the first target capacity output capacity. If the first target capacity output capacity is greater than the first equivalent output power, the active power input value of the energy storage device is adjusted to the maximum value, and the second equivalent output power and the second target capacity output capacity of the new energy power plant are calculated again. The second active power output value of the energy storage device is determined according to the relationship between the second equivalent output power and the second target capacity output capacity. If the second target capacity output capacity is greater than the second equivalent output power, the reactive power output value of the energy storage device is adjusted to the maximum value, and the third equivalent output power and the third target capacity output capacity of the new energy power plant are calculated again. The third reactive power output value of the energy storage device is determined based on the relationship between the third equivalent output power and the third target capacity output capacity. If the third target capacity output capacity is greater than the third equivalent output power, the reactive power output value of the new energy power generation device is adjusted to the maximum value, and the fourth equivalent output power and the fourth target capacity output capacity of the new energy power plant are calculated again. The fourth reactive power output value of the new energy power generation device is determined based on the relationship between the fourth equivalent output power and the fourth target capacity output capacity.

2. The multi-source coordinated voltage control method for new energy power plants according to claim 1, characterized in that, The reactive power output of the SVG control device is set to its maximum value. The first equivalent power output and the first target capacity output of the new energy power plant are calculated. Based on the relationship between the first equivalent power output and the first target capacity output, the first reactive power output value of the SVG device is determined, including: Adjust the reactive power output value of the SVG device to the maximum value to obtain the rated output capacity of the first AC system under the current state; The capacity of the energy storage device and the state of several inverters in the new energy power generation device are kept constant, and the first equivalent output power of the new energy power plant is calculated. Calculate the first target capacity output capacity based on the rated output capacity of the first AC system and the first equivalent output power. When the first target capacity output capacity is less than the first equivalent output power, the reactive power output value of the SVG device is controlled to be the difference between the target capacity output capacity and the sum of the reactive power output values ​​of the energy storage device and the new energy power generation device. When the first target capacity output capacity is greater than or equal to the first equivalent output power, the first reactive power output value of the SVG device is controlled to be the maximum value.

3. The multi-source coordinated voltage control method for new energy power plants according to claim 1, characterized in that, The process involves adjusting the active power input value of the energy storage device to its maximum value, recalculating the second reactive power demand value and the second reactive power supply value of the new energy power plant, and determining the second active power output value of the energy storage device based on the relationship between the second reactive power demand value and the second reactive power supply value. This includes: Adjust the active power input value of the energy storage device to its maximum value to obtain the rated output capacity of the second AC system under the current state; The states of several inverters in the SVG equipment and the new energy power generation device are kept unchanged, and the second equivalent output power of the new energy power plant is calculated. Calculate the second target capacity output capacity based on the rated output capacity of the second AC system and the second equivalent output power. When the second target capacity output capacity is less than the second equivalent output power, the reactive power absorption value of the energy storage device is controlled to be the difference between the target capacity output capacity and the output capacity of all other devices except the SVG device and the energy storage device. When the second target capacity output capacity is greater than or equal to the second equivalent output power, the second active power output value of the energy storage device is controlled to be the maximum value.

4. The multi-source coordinated voltage control method for new energy power plants according to claim 1, characterized in that, The process involves adjusting the reactive power output of the energy storage device to its maximum value, recalculating the third equivalent power output and the third target capacity output of the new energy power plant, and determining the third reactive power output value of the energy storage device based on the relationship between the third equivalent power output and the third target capacity output. This includes: Adjust the reactive power output value of the energy storage device to the maximum value to obtain the rated output capacity of the third AC system under the current state; The states of several inverters in the SVG device and the new energy power generation device are kept constant, and the active power output value of the energy storage device is kept constant. The third equivalent output power of the new energy power plant is calculated. Calculate the third target capacity output capacity based on the rated output capacity of the third AC system and the third equivalent output power. When the third target capacity output capacity is less than the third equivalent output power, the third reactive power output value of the energy storage device is controlled to be the difference between the target capacity output capacity and the sum of the reactive power output value of the SVG device, the active power output value of the energy storage device, and the output capacity of the new energy power generation device. When the third target capacity output capacity is greater than or equal to the third equivalent output power, the third reactive power output value of the energy storage device is controlled to be the maximum value.

5. The multi-source coordinated voltage control method for new energy power plants according to claim 1, characterized in that, The reactive power output value of the adjusted new energy power generation device is set to the maximum value, and the fourth equivalent output power and the fourth target capacity output capacity of the new energy power plant are calculated again. Based on the relationship between the fourth equivalent output power and the fourth target capacity output capacity, the fourth reactive power output value of the new energy power generation device is determined, including: Adjust the reactive power output value of the new energy power generation device to the maximum value to obtain the rated output capacity of the fourth AC system under the current state; By keeping the states of several inverters in the SVG device and the capacity of the energy storage device constant, the fourth equivalent output power of the new energy power plant is calculated. Calculate the fourth target capacity output capacity based on the rated output capacity of the fourth AC system and the fourth equivalent output power. When the fourth target capacity output capacity is less than the fourth equivalent output power, the fourth reactive power output value of the new energy power generation device is controlled to be the difference between the target capacity output capacity and the reactive power output value of the SVG device, the capacity of the energy storage device and the active power output value of the new energy power generation device. When the target capacity output capacity is greater than or equal to the equivalent output power, the fourth reactive power output value of the new energy power generation device is controlled to be the maximum value.

6. A multi-source coordinated voltage control system for new energy power plants, characterized in that, The new energy power plant includes: SVG equipment, energy storage devices, and new energy power generation devices; the voltage control system includes: A voltage detection module is used to acquire the voltage value of the PCC point of the new energy power plant; A power adjustment module is used to adjust the output power of the SVG device, energy storage device and new energy power generation device in sequence when the voltage value of the PCC point is lower than the preset voltage threshold, so that the voltage value of the PCC point reaches the preset voltage threshold. The power adjustment module includes: The SVG device adjustment unit is used to control the output reactive power of the SVG device to the maximum value, calculate the first equivalent power output and the first target capacity output capacity of the new energy power plant, and determine the first reactive power output value of the SVG device based on the relationship between the first equivalent power output and the first target capacity output capacity. The first energy storage adjustment unit is used to adjust the active power input value of the energy storage device to the maximum value if the first target capacity output capacity is greater than the first equivalent output power, and to recalculate the second equivalent output power and the second target capacity output capacity of the new energy power plant, and determine the second active power output value of the energy storage device based on the relationship between the second equivalent output power and the second target capacity output capacity. The second energy storage adjustment unit is used to adjust the reactive power output value of the energy storage device to the maximum value if the output capacity of the second target capacity is greater than the second equivalent output power, and to recalculate the third equivalent output power and the third target capacity output capacity of the new energy power plant, and determine the third reactive power output value of the energy storage device based on the relationship between the third equivalent output power and the third target capacity output capacity. The new energy power generation adjustment unit is used to adjust the output reactive power of the new energy power generation device to the maximum value if the output capacity of the third target capacity is greater than the third equivalent output power, and to recalculate the fourth equivalent output power and the fourth target capacity output capacity of the new energy power plant. Based on the relationship between the fourth equivalent output power and the fourth target capacity output capacity, the fourth reactive power output value of the new energy power generation device is determined.

7. An electronic device, characterized in that, include: At least one processor; The at least one processor is connected to a memory; wherein the memory stores instructions that can be executed by the at least one processor, the instructions being executed by the at least one processor to cause the at least one processor to perform the multi-source coordinated voltage control method for new energy power plants as described in any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, It stores computer instructions, which, when executed by a processor, implement the multi-source coordinated voltage control method for new energy power plants as described in any one of claims 1-5.

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