Multi-source cooperative voltage control method and system for new energy plant station

Abstract

The invention discloses a multi-source cooperative voltage control method and system for a new energy plant station, the new energy plant station comprises SVG equipment, an energy storage device and a new energy power generation device, and the voltage control method comprises the following steps: obtaining a PCC point voltage value of the new energy plant station; and when the voltage value of the PCC point is lower than the preset voltage threshold value, the output power of the SVG equipment, the energy storage device and the new energy power generation device is sequentially adjusted, so that the voltage value of the PCC point reaches the preset voltage threshold value. Multi-source cooperative voltage control is carried out on the new energy plant station, the SVG equipment, the energy storage device and the new energy power generation device are sequentially adjusted, the PCC point voltage of the new energy plant station is accurately regulated and controlled, the reactive power regulation capability of each equipment is fully exerted based on the output optimal principle, the stability and adaptability of the system are improved, and stable operation of the new energy plant station is guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of new energy plant control technology, and in particular to a new energy plant multi-source coordinated voltage control method and system. Background Art

[0002] The development of large-scale new energy bases has accelerated, and countries around the world are committed to developing new energy represented by wind and solar. However, the output of wind turbines and photovoltaic units is largely affected by the weather, and their power generation output has large random fluctuations, making the phenomenon of "abandoning wind" and "abandoning solar" on the power generation side often occur.

[0003] At present, photovoltaic power sources are mainly connected to the power system in two forms: one is large-capacity centralized access, and the other is distributed access. Among them, centralized photovoltaic power sources are mainly connected to the high-voltage transmission network, while distributed photovoltaic power sources are mainly connected to the distribution network. However, due to the technical characteristics of distributed power generation methods that are different from traditional energy generation methods, its large-scale grid connection will not only reduce environmental pressure and create economic benefits, but also increase the risk of safe operation of the distribution network, posing new challenges to the safe operation of the distribution network. After the distributed power source is connected, the distribution network structure will change from the traditional radial chain structure to a multi-power structure, which will change the original power flow and voltage distribution of the distribution network; the distributed power source has the characteristics of intermittent and volatile output itself, which may cause the voltage of each node of the distribution network line to fluctuate, thereby making the regulation and operation of the distribution network more complicated.

[0004] In addition, with the massive access of new energy systems, the short-circuit capacity of traditional power grids continues to decline, and the traditional power grids lack voltage regulation means, and their ability to control voltage is getting worse and worse, which leads to the voltage control ability of the entire system getting worse and worse. At present, the voltage support of new energy plants mainly adopts SVG for voltage support, but the support capacity of SVG is limited, especially in transient processes, and can only support the voltage of PCC points.

[0005] Reactive voltage control of large-scale new energy bases follows the principle of "layering and zoning, local balance", coordinates various reactive equipment in large-scale new energy bases, makes full use of the performance differences between various types of equipment, controls the voltage of each node in the area within the specified range, and ensures the safety of regional power grid voltage. During the operation of the power system, various inductive equipment and transformers consume a lot of reactive power. If not controlled, the power factor of the power system will decrease, affecting the stability of the system operation. Summary of the invention

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

[0007] In order to solve the above technical problems, a first aspect of an embodiment of the present invention provides a multi-source coordinated voltage control method for a new energy plant, wherein the new energy plant includes: an SVG device, an energy storage device, and a new energy power generation device, and the voltage control method includes the following steps:

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

[0009] When the voltage value at the PCC point is lower than a preset voltage threshold, the output powers of the SVG device, the energy storage device and the new energy power generation device are adjusted in sequence so that the voltage value at the PCC point reaches the preset voltage threshold.

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

[0011] Controlling the output reactive power of the SVG device to be a maximum value, calculating the first equivalent output power and the first target output capacity of the new energy plant, and determining the first reactive power output value of the SVG device according to the relationship between the first equivalent output power and the first target 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 plant are calculated again, and 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 plant are calculated again, and the third reactive power output value of the energy storage device is determined according to the magnitude relationship between the third equivalent output power and the third target capacity output capacity;

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

[0015] Further, the output reactive power of the SVG device is controlled to be a maximum value, a first equivalent output power and a first target output capacity of the new energy plant are calculated, and a first reactive power output value of the SVG device is determined according to a relationship between the first equivalent output power and the first target output capacity, including:

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

[0017] Respectively controlling the capacity of the energy storage device and the states of several inverters in the new energy power generation device to remain unchanged, and calculating the first equivalent output power of the new energy plant;

[0018] Calculating a 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 a maximum value.

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

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

[0023] respectively controlling the states of several inverters in the SVG device and the new energy power generation device to remain unchanged, and calculating the second equivalent output power of the new energy plant;

[0024] Calculating a 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 a maximum value.

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

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

[0029] Controlling the states of several inverters in the SVG device and the new energy power generation device to remain unchanged respectively, and controlling the active power output value of the energy storage device to remain unchanged, and calculating the third equivalent output power of the new energy plant;

[0030] Calculating a third target capacity output capacity based on the third AC system rated output capacity 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 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 a maximum value.

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

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

[0035] Controlling the states of several inverters in the SVG device and the capacity of the energy storage device to remain unchanged, and calculating the fourth equivalent output power of the new energy plant;

[0036] Calculating a fourth target capacity output capacity based on the fourth AC system rated output capacity 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 an embodiment of the present invention provides a new energy plant multi-source coordinated voltage control system, wherein the new energy plant comprises: an SVG device, an energy storage device and a new energy power generation device, and the voltage control system comprises:

[0040] A voltage detection module, which is used to obtain the PCC point voltage value of the new energy 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] an SVG device adjustment unit, which is used to control the output reactive power of the SVG device to be a maximum value, calculate the first equivalent output power and the first target output capacity of the new energy plant, and determine the first reactive power output value of the SVG device according to the relationship between the first equivalent output power and the first target output capacity;

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

[0045] A second energy storage adjustment unit, which is used to adjust the reactive power output value of the energy storage device to a maximum value if the second target capacity output capacity is greater than the second equivalent output power, and recalculate the third equivalent output power and the third target capacity output capacity of the new energy plant, and determine the third reactive power output value of the energy storage device according to the magnitude 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 value of the new energy power generation device to a maximum value if the third target capacity output capacity is greater than the third equivalent output power, and recalculate the fourth equivalent output power and the fourth target capacity output capacity of the new energy plant, and determine the fourth reactive power output value of the new energy power generation device according to the size relationship between the fourth equivalent output power and the fourth target capacity output capacity.

[0047] Correspondingly, a third aspect of an embodiment of the present invention provides an electronic device, comprising: 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, and the instructions are executed by the at least one processor so that the at least one processor executes the above-mentioned new energy plant multi-source collaborative voltage control method.

[0048] Correspondingly, a fourth aspect of an embodiment of the present invention provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the above-mentioned new energy plant multi-source coordinated voltage control method.

[0049] The above technical solution of the embodiment of the present invention has the following beneficial technical effects:

[0050] 1. Integrate SVG equipment, energy storage devices and new energy power generation devices for coordinated control, with clear steps and judgment basis for adjusting the output power of each device, and realize fine control of the voltage of new energy plants. Each device plays a role at different stages and cooperates with each other to dynamically adjust the output according to the actual needs of the system, thus 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 turn, their advantages in reactive power and active power adjustment can be fully utilized to ensure the stable operation of new energy plants and stations and reduce the adverse effects of voltage fluctuations;

[0052] 3. Under different system conditions, the output value of each device is determined based on a reasonable calculation method. The output of the device is flexibly adjusted according to the relationship between the target capacity output capacity and the equivalent output power, so that the system can better adapt to different voltage changes and improve the stability and reliability of new energy plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 It is a schematic diagram of the topological structure of a new energy plant provided by an embodiment of the present invention;

[0054] Figure 2 It is a flow chart of a multi-source coordinated voltage control method for a new energy plant provided by an embodiment of the present invention;

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

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

[0057] Reference numerals:

[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 DESCRIPTION

[0059] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0060] Please refer to Figure 1 and Figure 2 A first aspect of an embodiment of the present invention provides a multi-source coordinated voltage control method for a new energy plant, wherein the new energy plant includes: an SVG device, an energy storage device, and a new energy power generation device, and the voltage control method includes the following steps:

[0061] Step S100, obtaining the PCC point voltage value of the new energy plant.

[0062] By obtaining the PCC point voltage value of the new energy plant, the voltage status of the plant can be grasped 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 accurate response.

[0063] Step S200, when the voltage value at the PCC point is lower than a 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 increase the voltage value at the PCC point so that the voltage value at the PCC point reaches the preset voltage threshold.

[0064] By integrating and controlling various types of equipment such as SVG equipment, energy storage devices, and new energy power generation devices, SVG equipment can quickly adjust reactive power output; energy storage devices have flexible active and reactive power adjustment capabilities; and new energy power generation devices can also provide reactive power support to a certain extent. Each device cooperates with each other, gives full play to its own advantages, and complements each other. The output power of different equipment is adjusted in turn, and targeted regulation can be carried out according to the characteristics and actual conditions of different equipment, thereby improving the flexibility and effectiveness of voltage control.

[0065] Both the new energy system and the energy storage system have a certain reactive power support capability. In the new energy plant, the reactive power of each device should be fully utilized to achieve comprehensive regulation of the AC voltage. Based on the reactive power support capability of the new energy system and the energy storage system, they are fully utilized in the plant to achieve comprehensive regulation of the AC voltage. This helps to improve the stability and reliability of the power system and reduce the adverse effects caused by voltage fluctuations. By effectively controlling the voltage at the PCC point, the voltage value reaches the preset voltage threshold, which ensures the stable operation of the new energy plant, reduces the risk of equipment damage, and improves the overall safety and reliability of the power system.

[0066] like Figure 1 As shown in the figure, the basic structure diagram of a new energy plant is shown, where the inverter can represent a photovoltaic inverter, a wind turbine inverter, an energy storage inverter, and an SVG inverter.

[0067] Assume the active power of inverter n is P n , the reactive power is Q n , the port voltage is U n , the branch current is I n , the DC impedance is X n , then:

[0068]

[0069] where α n is the phase angle of the voltage and current at the inverter n output.

[0070] Assume the voltage of the PCC point of the new energy plant is U pcc , the equivalent voltage of the AC system is U s , the system equivalent impedance is X s , the equivalent current is I s . Then we have:

[0071]

[0072] where δ n is the phase angle between the voltage of the new energy plant and the equivalent current of the system. j represents the symbol of the imaginary part of the complex domain.

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

[0074] I s =∑I n +I X (3)

[0075] Among them I x Represents the equivalent current collected by other plants or AC systems.

[0076] According to formula (2), when the grid structure is fixed, the equivalent voltage of the AC system is U s , equivalent impedance I s will not change, so the change of PCC point voltage is mainly caused by I s In the process of voltage regulation at the new energy station, I n Changes in I s Considering that the reactive power of the AC system is mainly balanced locally, the equivalent model of the AC system mainly considers the reactive power transmission and the reactive power consumption of the equivalent impedance. Therefore, the voltage drop at the PCC point caused by the current change can be expressed as follows:

[0077]

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

[0079] in

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

[0081] Where S p is the equivalent output power of the new energy plant, S o is the equivalent capacity of other AC systems. When the equivalent capacity of other AC systems increases, S o Increase will cause voltage drop.

[0082]

[0083] When the voltage drops, on the one hand, the voltage can be increased by adjusting the output power, and on the other hand, the reactive power generated can be increased to supplement S o Part of the reactive power is used to increase the voltage.

[0084] If we assume that the minimum target value of voltage regulation is set to K pcc , then the target capacity output capacity is:

[0085]

[0086] Where K pcc Generally not less than 0.95.

[0087] Monitor the PCC voltage. When the PCC voltage is lower than K pcc When , the target capacity output capacity is calculated according to formula (7):

[0088]

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

[0090] According to formula (6), it is necessary to adjust the state of each inverter to satisfy formula (8).

[0091] There are clear steps and judgment bases for adjusting the output power of each device, which realizes the fine control of the voltage of the new energy plant. By gradually adjusting the output power of different devices, it is possible to more accurately find the optimal combination that makes the PCC point voltage value reach the preset voltage threshold.

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

[0093] Step S210, controlling the output reactive power of the SVG device to be a maximum value, calculating the first equivalent output power and the first target output capacity of the new energy plant, and determining the first reactive power output value of the SVG device according to the relationship between the first equivalent output power and the first target output capacity.

[0094] Adjust the output reactive power of the SVG equipment to the maximum value, and use the characteristics of the SVG equipment to quickly adjust the reactive power to quickly respond to voltage changes. Calculate the first equivalent output power and the first target capacity output capacity, and determine the first reactive power output value of the SVG equipment based on the relationship between the two, 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 plant are calculated again, and 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.

[0096] If the output capacity of the first target 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. This step fully utilizes the active power regulation capability of the energy storage device, affects the system state by absorbing active power, calculates the second equivalent output power and the second target capacity output capacity again, and determines the second active power output value of the energy storage device.

[0097] Step S230: 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 plant are calculated again, and the third reactive power output value of the energy storage device is determined according to the relationship between the third equivalent output power and the third target capacity output capacity.

[0098] 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. To further tap the reactive power regulation potential of the energy storage device, the third equivalent output power and the third target capacity output capacity are calculated again to determine the third reactive power output value of the energy storage device.

[0099] Step S240, if the third target capacity output capacity is greater than the third equivalent output power, the output 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 plant are calculated again, and the fourth reactive power output value of the new energy power generation device is determined according to the size 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 output reactive power output value of the new energy power generation device is finally adjusted to the maximum value. The fourth equivalent output power and the fourth target capacity output capacity are calculated again by using the reactive support capacity of the new energy power generation device to determine the fourth reactive power output value of the new energy power generation device.

[0101] Throughout the process, SVG equipment, energy storage devices and new energy power generation devices play their roles in turn and work together to effectively control the voltage of new energy plants. 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. Through this phased and targeted adjustment method, it can better adapt to different voltage changes and improve the stability and reliability of new energy plants. When the voltage is lower than the preset threshold, timely and effective measures can be taken to restore the voltage value of the PCC point to the preset voltage threshold to ensure the normal operation of the power system.

[0102] Furthermore, in step S210, the output reactive power of the SVG device is controlled to be a maximum value, a first equivalent output power and a first target output capacity of the new energy plant are calculated, and a first reactive power output value of the SVG device is determined according to a relationship between the first equivalent output power and the first target output capacity, including:

[0103] Step S211, adjusting the reactive power output value of the SVG device to a maximum value, and obtaining the rated output capacity of the first AC system in the current state.

[0104] Step S212, respectively controlling the capacity of the energy storage device and the states of several inverters in the new energy power generation device to remain unchanged, and calculating the first equivalent output power of the new energy plant.

[0105] The capacity of the energy storage device and the states of several inverters in the new energy power generation device are controlled to remain unchanged, and the first equivalent output power of the new energy 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 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. This method of flexibly adjusting the reactive power output according to different situations can ensure that the SVG device can play the best regulatory role in 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 a 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 maximum, so as to make full use of the regulation capability of the SVG device and quickly respond to the voltage change demand of the system.

[0111] During the whole process, SVG equipment cooperates with energy storage devices and new energy power generation devices. By reasonably adjusting the reactive power output of SVG equipment, multi-source coordinated control is achieved, optimizing the system performance of new energy plants. Under different system states, the output of each device can be dynamically adjusted according to actual needs, improving the adaptability and stability of the system.

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

[0113] Step S221, adjusting the active power input value of the energy storage device to a maximum value, and obtaining the rated output capacity of the second AC system in the current state.

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

[0115] Step S222, respectively controlling the states of several inverters in the SVG device and the new energy power generation device to remain unchanged, and calculating the second equivalent output power of the new energy plant.

[0116] The states of several inverters in the SVG equipment and the new energy power generation device are controlled to remain unchanged, and the second equivalent output power of the new energy 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 can more accurately reflect the role of the energy storage device.

[0117] Step S223, calculating 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 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. This method of flexibly adjusting the reactive power absorption value according to different situations can ensure that the energy storage device can play the best regulatory role in 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 a 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 be maximum, so as to make full use of the regulation capability of the energy storage device and quickly respond to the voltage change demand of the system.

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

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

[0124] Step S231, adjusting the reactive power output value of the energy storage device to a maximum value, and obtaining the rated output capacity of the third AC system in the current state.

[0125] By adjusting the reactive power output value of the energy storage device to the maximum value, the ability of the energy storage device in reactive power regulation can be fully utilized to improve the voltage stability of the new energy plant.

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

[0127] The states of several inverters in the SVG equipment and the new energy power generation device are controlled to remain unchanged, and the active power output value of the energy storage device is controlled to remain unchanged, and the third equivalent output power of the new energy plant is calculated. This method ensures that when analyzing the impact of the reactive power output 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 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 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 to be the difference between the target capacity output capacity and 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 can ensure that the energy storage device can play the best regulatory role in 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 a 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 be maximum, so as to make full use of the regulation capability of the energy storage device and quickly respond to the voltage change demand of the system.

[0133] During the entire process, the energy storage device cooperates with the SVG equipment and the new energy power generation device. By rationally adjusting the reactive power output of the energy storage device, multi-source coordinated control is achieved, thus optimizing the system performance of the new energy plant.

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

[0135] Step S241, adjusting the reactive power output value of the new energy power generation device to a maximum value, and obtaining the rated output capacity of the fourth AC system in the current state.

[0136] Step S242, controlling the states of several inverters and the capacity of the energy storage device in the SVG device to remain unchanged, and calculating the fourth equivalent output power of the new energy plant.

[0137] The states of several inverters and the capacity of energy storage devices in the SVG equipment are controlled to remain unchanged, and the fourth equivalent output power of the new energy plant is calculated. This method ensures that when analyzing the impact of the reactive power output of the new energy power generation device on the system, the interference of changes in the state of other equipment is eliminated.

[0138] Step S243, calculating a fourth target capacity output capacity based on the rated output capacity of the fourth AC system 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 capacity of the energy storage device 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 equipment, 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 be the maximum value, making full use of the regulation capability of the new energy power generation device and quickly responding 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 and the system performance of new energy plants can be optimized.

[0144] Accordingly, please refer to Figure 3 A second aspect of an embodiment of the present invention provides a new energy plant multi-source coordinated voltage control system, the new energy plant includes: SVG equipment, energy storage device and new energy power generation device, the voltage control system includes:

[0145] Voltage detection module 1, which is used to obtain the PCC point voltage value of the new energy plant;

[0146] The power adjustment module 2 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.

[0147] For further information, 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 be a maximum value, calculate the first equivalent output power and the first target output capacity of the new energy plant, and determine the first reactive power output value of the SVG device according to the relationship between the first equivalent output power and the first target 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 a maximum value if the first target capacity output capacity is greater than the first equivalent output power, and calculate the second equivalent output power and the second target capacity output capacity of the new energy plant again, and determine the second active power output value of the energy storage device according to 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 a maximum value if the second target capacity output capacity is greater than the second equivalent output power, and calculate the third equivalent output power and the third target capacity output capacity of the new energy plant again, and determine the third reactive power output value of the energy storage device according to 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 value 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 recalculate the fourth equivalent output power and the fourth target capacity output capacity of the new energy plant, and determine the fourth reactive power output value of the new energy power generation device according to the size relationship between the fourth equivalent output power and the fourth target capacity output capacity.

[0152] Correspondingly, a third aspect of an embodiment of the present invention provides an electronic device, comprising: at least one processor; and a memory connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor executes the above-mentioned new energy plant multi-source collaborative voltage control method.

[0153] Correspondingly, a fourth aspect of an embodiment of the present invention provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the above-mentioned new energy plant multi-source coordinated voltage control method.

[0154] The embodiment of the present invention aims to protect a multi-source coordinated voltage control method and system for a new energy plant. The new energy plant includes: SVG equipment, energy storage device and new energy power generation device. The voltage control method includes the following steps: obtaining the PCC point voltage value of the new energy plant; when the PCC point voltage value is lower than the preset voltage threshold, adjusting the output power of the SVG equipment, energy storage device and new energy power generation device in turn, so that the PCC point voltage value reaches the preset voltage threshold. The above technical solution has the following effects:

[0155] 1. Integrate SVG equipment, energy storage devices and new energy power generation devices for coordinated control, with clear steps and judgment basis for adjusting the output power of each device, and realize fine control of the voltage of new energy plants. Each device plays a role at different stages and cooperates with each other to dynamically adjust the output according to the actual needs of the system, thus 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 turn, their advantages in reactive power and active power adjustment can be fully utilized to ensure the stable operation of new energy plants and stations and reduce the adverse effects of voltage fluctuations;

[0157] 3. Under different system conditions, the output value of each device is determined based on a reasonable calculation method. The output of the device is flexibly adjusted according to the relationship between the target capacity output capacity and the equivalent output power, so that the system can better adapt to different voltage changes and improve the stability and reliability of new energy plants.

[0158] 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.

[0159] 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.

[0160] 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.

[0161] 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.

[0162] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does 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 a new energy plant, characterized in that: The new energy plant station includes: SVG equipment, energy storage device and new energy power generation device, and the voltage control method includes the following steps: Obtaining the PCC point voltage value of the new energy plant; When the voltage value at the PCC point is lower than a preset voltage threshold, the output powers of the SVG device, the energy storage device and the new energy power generation device are adjusted in sequence so that the voltage value at the PCC point reaches the preset voltage threshold.

2. The multi-source coordinated voltage control method for a new energy plant according to claim 1 is characterized in that: The step of sequentially adjusting the output power of the SVG device, the energy storage device and the new energy power generation device comprises: Controlling the output reactive power of the SVG device to be a maximum value, calculating the first equivalent output power and the first target output capacity of the new energy plant, and determining the first reactive power output value of the SVG device according to the relationship between the first equivalent output power and the first target 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 plant are calculated again, and 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 plant are calculated again, and the third reactive power output value of the energy storage device is determined according to the magnitude relationship between the third equivalent output power and the third target capacity output capacity; If the output capacity of the third target capacity is greater than the third equivalent output power, the output reactive power 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 plant are calculated again, and the fourth reactive power output value of the new energy power generation device is determined according to the relationship between the fourth equivalent output power and the fourth target capacity output capacity.

3. The multi-source coordinated voltage control method for a new energy plant according to claim 2 is characterized in that: The controlling the output reactive power of the SVG device to be the maximum value, calculating the first equivalent output power and the first target output capacity of the new energy plant, and determining the first reactive power output value of the SVG device according to the relationship between the first equivalent output power and the first target output capacity, comprises: Adjust the reactive power output value of the SVG device to a maximum value, and obtain the rated output capacity of the first AC system in the current state; Respectively controlling the capacity of the energy storage device and the states of several inverters in the new energy power generation device to remain unchanged, and calculating the first equivalent output power of the new energy plant; Calculating a 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 a maximum value.

4. The multi-source coordinated voltage control method for a new energy plant according to claim 2 is characterized in that: The step of adjusting the active power input value of the energy storage device to a maximum value, and recalculating the second reactive power demand value and the second reactive power supply value of the new energy plant, and determining the second active power output value of the energy storage device based on the magnitude relationship between the second reactive power demand value and the second reactive power supply value, comprises: Adjusting the active power input value of the energy storage device to a maximum value to obtain the rated output capacity of the second AC system in the current state; respectively controlling the states of several inverters in the SVG device and the new energy power generation device to remain unchanged, and calculating the second equivalent output power of the new energy plant; Calculating a 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 a maximum value.

5. The multi-source coordinated voltage control method for a new energy plant according to claim 2 is characterized in that: The step of adjusting the reactive power output value of the energy storage device to a maximum value, and calculating the third equivalent output power and the third target output capacity of the new energy plant again, and determining the third reactive power output value of the energy storage device according to the magnitude relationship between the third equivalent output power and the third target output capacity, comprises: Adjust the reactive power output value of the energy storage device to a maximum value, and obtain the rated output capacity of the third AC system in the current state; Controlling the states of several inverters in the SVG device and the new energy power generation device to remain unchanged respectively, and controlling the active power output value of the energy storage device to remain unchanged, and calculating the third equivalent output power of the new energy plant; Calculating a third target capacity output capacity based on the third AC system rated output capacity 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 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 a maximum value.

6. The multi-source coordinated voltage control method for a new energy plant according to claim 2 is characterized in that: The method of adjusting the output reactive power value of the new energy power generation device to a maximum value, and calculating the fourth equivalent output power and the fourth target output capacity of the new energy plant again, and determining the fourth reactive power output value of the new energy power generation device according to the magnitude relationship between the fourth equivalent output power and the fourth target output capacity, comprises: Adjust the reactive power output value of the new energy power generation device to a maximum value, and obtain the rated output capacity of the fourth AC system in the current state; Controlling the states of several inverters in the SVG device and the capacity of the energy storage device to remain unchanged, and calculating the fourth equivalent output power of the new energy plant; Calculating a fourth target capacity output capacity based on the fourth AC system rated output capacity 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.

7. A new energy plant multi-source coordinated voltage control system, characterized in that: The new energy plant station includes: SVG equipment, energy storage device and new energy power generation device, and the voltage control system includes: A voltage detection module, which is used to obtain the PCC point voltage value of the new energy plant; 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.

8. The multi-source coordinated voltage control system for new energy plants according to claim 7 is characterized in that: The power adjustment module comprises: an SVG device adjustment unit, which is used to control the output reactive power of the SVG device to be a maximum value, calculate the first equivalent output power and the first target output capacity of the new energy plant, and determine the first reactive power output value of the SVG device according to the relationship between the first equivalent output power and the first target output capacity; A first energy storage adjustment unit, which is used to adjust the active power input value of the energy storage device to a maximum value if the first target capacity output capacity is greater than the first equivalent output power, and recalculate the second equivalent output power and the second target capacity output capacity of the new energy plant, and determine the second active power output value of the energy storage device according to the relationship between the second equivalent output power and the second target capacity output capacity; A second energy storage adjustment unit, which is used to adjust the reactive power output value of the energy storage device to a maximum value if the second target capacity output capacity is greater than the second equivalent output power, and recalculate the third equivalent output power and the third target capacity output capacity of the new energy plant, and determine the third reactive power output value of the energy storage device according to the magnitude 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 value of the new energy power generation device to a maximum value if the third target capacity output capacity is greater than the third equivalent output power, and recalculate the fourth equivalent output power and the fourth target capacity output capacity of the new energy plant, and determine the fourth reactive power output value of the new energy power generation device according to the size relationship between the fourth equivalent output power and the fourth target capacity output capacity.

9. An electronic device, characterized in that: include: at least one processor; And a memory connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor executes the multi-source collaborative voltage control method for a new energy plant as described in any one of claims 1-6.

10. A computer-readable storage medium, characterized in that: Computer instructions are stored thereon, which, when executed by a processor, implement the multi-source coordinated voltage control method for a new energy plant as described in any one of claims 1-6.

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