Electric energy quality management fusion system and comprehensive control method thereof

Abstract

The embodiment of the invention discloses an electric energy quality control fusion system and a comprehensive control method thereof, and the system comprises a comprehensive grounding transformer, a reactive power adjustable transformer, a series reactor, a reactive power compensation capacitor, an arc extinction adjustable transformer, and an arc extinction selection switch. The reactive power adjustable transformer is used for outputting a first stepless adjustable voltage, the arc extinction selection switch is used for closing a phase switch corresponding to a grounding fault phase under the condition that a power system needs grounding compensation, and the arc extinction adjustable transformer is used for outputting a second stepless adjustable voltage; through reasonable design, reactive compensation and grounding compensation can be achieved at the same time, reactive compensation does not need to be quitted when grounding compensation is carried out, the situation that protection action is too complex and power frequency resonance transient overvoltage is caused is avoided, and the arc extinguishing capacity and the reactive compensation capacity which are quick in response are achieved.

Description

Technical Field

[0001] The present invention relates to the field of power protection technology, and in particular to a power quality management fusion system and a comprehensive control method thereof. Background Art

[0002] In recent years, the widespread application of power systems has promoted the efficient operation of social production, and also provided a solid foundation for the development of the national economy and the improvement of comprehensive national strength. As an important guarantee for the stable operation of the power system, power quality management not only involves the management of power loss, but also includes the prevention and control of power quality problems, which improves the reliability and economy of the power system.

[0003] Power quality control measures mainly include reactive power compensation and grounding compensation. Reactive power compensation aims to improve the power factor of the power system, reduce reactive power loss, improve grid efficiency, and thus enhance the stability of the power system; while grounding compensation aims to reduce grounding resistance and effectively prevent overvoltage problems caused by grounding faults in the power grid, thereby ensuring the safe operation of power equipment.

[0004] However, the existing power quality management fusion system applied to the power system (i.e., the fusion system of arc extinguishing device and reactive power compensation device) often needs to exit reactive power compensation when performing grounding compensation. This not only increases the complexity of the protection action, but may also cause power frequency resonant transient overvoltage, posing a threat to the stability of the power system, and does not have the ability to quickly respond to arc extinguishing and reactive power compensation. Summary of the invention

[0005] Based on this, it is necessary to propose a power quality management fusion system and its comprehensive control method to address the above problems. Through reasonable design, reactive power compensation and grounding compensation can be realized at the same time, so that there is no need to exit reactive compensation when grounding compensation is performed, avoiding excessive complexity of protection action and causing power frequency resonance transient overvoltage. It also has fast response arc extinguishing capability and reactive power compensation capability.

[0006] To achieve the above-mentioned object, the present invention provides a power quality management fusion system in a first aspect, the system comprising a comprehensive grounding transformer, a reactive power adjustable transformer, a series reactor, a reactive power compensation capacitor, an arc extinguishing adjustable transformer and an arc extinguishing selection switch;

[0007] The primary side of the integrated grounding transformer is connected to the three-phase busbar of the power system in three phases, and the secondary side of the integrated grounding transformer is respectively connected to the primary side of the reactive power adjustable transformer and the primary side of the arc-extinguishing adjustable transformer in three phases; the secondary side of the reactive power adjustable transformer is connected to one side of the series reactor in three phases, and the other side of the series reactor is connected to the reactive power compensation capacitor in three phases; the secondary side of the arc-extinguishing adjustable transformer is connected to one side of the arc-extinguishing selection switch in three phases, and the other side of the arc-extinguishing selection switch is short-circuited with the neutral point of the primary side of the integrated grounding transformer, and the neutral point of the secondary side of the arc-extinguishing adjustable transformer is grounded;

[0008] In the case where the power system requires reactive power compensation, the reactive power adjustable transformer is used to output a first steplessly adjustable voltage;

[0009] In the case where the power system requires grounding compensation, the arc extinguishing selection switch is used to close the phase switch corresponding to the grounding fault phase, and the arc extinguishing adjustable transformer is used to output a second steplessly adjustable voltage.

[0010] Optionally, the system further comprises an integrated controller;

[0011] The integrated controller is respectively connected to the reactive power adjustable transformer, the arc extinguishing adjustable transformer, and the arc extinguishing selection switch;

[0012] In the case where the power system requires reactive power compensation, the integrated controller is used to determine the first steplessly adjustable voltage according to the current active power and the current reactive power of the power system, and the rated capacity and the rated voltage of the reactive compensation capacitor, and control the reactive adjustable transformer to output the first steplessly adjustable voltage;

[0013] When the power system requires grounding compensation, the integrated controller is used to determine the grounding fault phase and the second steplessly adjustable voltage, and control the arc extinguishing selection switch to close the phase switch corresponding to the grounding fault phase, and control the arc extinguishing adjustable transformer to output the second steplessly adjustable voltage.

[0014] Optionally, the capacity of the integrated grounding transformer is greater than or equal to the sum of the capacities of the reactive adjustable transformer and the arc-extinguishing adjustable transformer, the capacity of the reactive adjustable transformer is greater than or equal to the reactive capacity required for reactive compensation of the power system, and the capacity of the arc-extinguishing adjustable transformer is greater than or equal to 3 times the maximum capacity required for grounding compensation of the power system.

[0015] Optionally, the reactive power compensation capacitor adopts a star connection mode or a triangle connection mode.

[0016] To achieve the above object, the present invention provides, in a second aspect, a comprehensive control method for a power quality management fusion system, the method being applied to a system as described in any one of the first aspects, the method comprising:

[0017] Acquiring the current active power and the current reactive power of the power system, as well as the rated capacity and the rated voltage of the reactive compensation capacitor;

[0018] In the case where the power system requires reactive power compensation, determining a first steplessly adjustable voltage according to the current active power, the current reactive power, the rated capacity and the rated voltage, and controlling the reactive power adjustable transformer in the system to output the first steplessly adjustable voltage;

[0019] In the case where the power system requires grounding compensation, the grounding fault phase and the second steplessly adjustable voltage are determined, and the arc extinguishing selection switch in the system is controlled to close the phase switch corresponding to the grounding fault phase, and the arc extinguishing adjustable transformer in the system is controlled to output the second steplessly adjustable voltage.

[0020] Optionally, determining the first steplessly adjustable voltage according to the current active power, the current reactive power, the rated capacity and the rated voltage includes:

[0021] Get the power factor threshold;

[0022] The first steplessly adjustable voltage is determined according to the power factor threshold, the current active power, the current reactive power, the rated capacity and the rated voltage.

[0023] Optionally, determining the first steplessly adjustable voltage according to the power factor threshold, the current active power, the current reactive power, the rated capacity and the rated voltage includes:

[0024] Using the formula determining the first steplessly adjustable voltage;

[0025] Among them, U1 is the first steplessly adjustable voltage, U e is the rated voltage, P is the current active power, λ TH is the power factor threshold, Q e is the rated capacity, and Q is the current reactive power.

[0026] Optionally, the method further comprises:

[0027] Get the power factor threshold;

[0028] Determining a current power factor according to the current active power and the current reactive power;

[0029] When the current power factor is less than the power factor threshold, it is determined that the power system requires reactive power compensation.

[0030] Optionally, determining the second steplessly adjustable voltage includes:

[0031] Obtaining an average value of line voltages of three-phase buses of the power system;

[0032] The second steplessly adjustable voltage is determined according to the average value.

[0033] Optionally, the method further comprises:

[0034] Acquiring a current grounding state of the power system;

[0035] When the current grounding state is a grounding fault, it is determined that the power system needs grounding compensation.

[0036] To achieve the above object, the present invention provides, in a third aspect, an integrated control device for a power quality management fusion system, the device being applied to a system as described in any one of the first aspects, the device comprising:

[0037] An acquisition module, used for acquiring the current active power and the current reactive power of the power system, and the rated capacity and the rated voltage of the reactive compensation capacitor;

[0038] A reactive power compensation module, used for determining a first steplessly adjustable voltage according to the current active power, the current reactive power, the rated capacity and the rated voltage when the power system needs reactive power compensation, and controlling the reactive power adjustable transformer in the system to output the first steplessly adjustable voltage;

[0039] A grounding compensation module is used to determine the grounding fault phase and the second stepless adjustable voltage when the power system requires grounding compensation, and to control the arc extinguishing selection switch in the system to close the phase switch corresponding to the grounding fault phase, and to control the arc extinguishing adjustable transformer in the system to output the second stepless adjustable voltage.

[0040] To achieve the above-mentioned purpose, the present invention provides in a fourth aspect a computer-readable storage medium storing a computer program, wherein when the computer program is executed by an integrated controller, the integrated controller executes the method as described in any one of the first aspects.

[0041] To achieve the above-mentioned purpose, the present invention provides a computer device in a fifth aspect, including a memory and an integrated controller, wherein the memory stores a computer program, and when the computer program is executed by the integrated controller, the integrated controller executes the method as described in any one of the first aspects.

[0042] The embodiment of the present invention has the following beneficial effects: the system is connected to the three-phase busbar of the power system through the primary side of the integrated grounding transformer, the secondary side of the integrated grounding transformer is respectively connected to the primary side of the reactive power adjustable transformer and the primary side of the arc extinguishing adjustable transformer, the secondary side of the reactive power adjustable transformer is connected to one side of the series reactor for three phases, the other side of the series reactor is connected to the reactive power compensation capacitor for three phases, the secondary side of the arc extinguishing adjustable transformer is connected to one side of the arc extinguishing selection switch for three phases, the other side of the arc extinguishing selection switch is short-circuited and connected to the neutral point of the primary side of the integrated grounding transformer. The neutral point of the secondary side of the arc-extinguishing adjustable transformer is grounded. When the power system requires reactive power compensation, the reactive power adjustable transformer is used to output a first stepless adjustable voltage. When the power system requires grounding compensation, the arc-extinguishing selection switch is used to close the phase switch corresponding to the grounding fault phase, and the arc-extinguishing adjustable transformer is used to output a second stepless adjustable voltage. That is, through reasonable design, reactive power compensation and grounding compensation can be achieved at the same time, so that there is no need to exit reactive power compensation when grounding compensation is performed, avoiding excessive complexity of protection action and causing power frequency resonance transient overvoltage, and it also has fast response arc extinguishing capability and reactive power compensation capability. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0044] in:

[0045] Figure 1 A schematic diagram of a power quality management fusion system in an embodiment of the present application Figure 1 ;

[0046] Figure 2 A schematic diagram of a power quality management fusion system in an embodiment of the present application Figure 2 ;

[0047] Figure 3 A schematic diagram of a power quality management fusion system in an embodiment of the present application Figure 3 ;

[0048] Figure 4 A schematic diagram of a comprehensive control method for a power quality management fusion system in an embodiment of the present application;

[0049] Figure 5 A schematic diagram of the waveforms of reactive power and active power of the power system during simulation verification in an embodiment of the present application;

[0050] Figure 6 A schematic diagram of a comprehensive control device for a power quality management fusion system in an embodiment of the present application;

[0051] Figure 7 1 is a diagram of the internal structure of a computer device in some embodiments. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] In recent years, the widespread application of power systems has promoted the efficient operation of social production, and also provided a solid foundation for the development of the national economy and the improvement of comprehensive national strength. As an important guarantee for the stable operation of the power system, power quality management not only involves the management of power loss, but also includes the prevention and control of power quality problems, which improves the reliability and economy of the power system.

[0054] Power quality control measures mainly include reactive power compensation and grounding compensation. Reactive power compensation aims to improve the power factor of the power system, reduce reactive power loss, improve grid efficiency, and thus enhance the stability of the power system; while grounding compensation aims to reduce grounding resistance and effectively prevent overvoltage problems caused by grounding faults in the power grid, thereby ensuring the safe operation of power equipment.

[0055] However, the existing power quality management fusion system applied to the power system (i.e., the fusion system of arc extinguishing device and reactive power compensation device) often needs to exit reactive power compensation when performing grounding compensation. This not only increases the complexity of the protection action, but may also cause power frequency resonant transient overvoltage, posing a threat to the stability of the power system, and does not have the ability to quickly respond to arc extinguishing and reactive power compensation.

[0056] In response to the above problems, the present application proposes a power quality management fusion system and its comprehensive control method. Through reasonable design, it can realize reactive power compensation and grounding compensation at the same time, so that there is no need to exit reactive power compensation when performing grounding compensation, avoiding overly complicated protection actions and causing power frequency resonant transient overvoltage. It also has fast response arc extinguishing capability and reactive power compensation capability. The specific implementation principle will be described in detail in the following embodiments.

[0057] In a first aspect, the present application provides a power quality management fusion system.

[0058] See also Figure 1, which is a schematic diagram of a power quality management fusion system in an embodiment of the present application Figure 1 The system includes an integrated grounding transformer 110, a reactive power adjustable transformer 140, a series inductor 150, a reactive power compensation capacitor 160, an arc extinguishing adjustable transformer 120 and an arc extinguishing selection switch 130.

[0059] Among them, the primary side of the integrated grounding transformer 110 is connected to the three-phase bus of the power system in three phases, and the secondary side of the integrated grounding transformer 110 is respectively connected to the primary side of the reactive power adjustable transformer 140 and the primary side of the arc-extinguishing adjustable transformer 120 in three phases; the secondary side of the reactive power adjustable transformer 140 is connected to one side of the series inductor 150 in three phases, and the other side of the series inductor 150 is connected to the reactive power compensation capacitor 160 in three phases; the secondary side of the arc-extinguishing adjustable transformer 120 is connected to one side of the arc-extinguishing selection switch 130 in three phases, and the other side of the arc-extinguishing selection switch 130 is short-circuited with the neutral point of the primary side of the integrated grounding transformer 110 in three phases, and the neutral point of the secondary side of the arc-extinguishing adjustable transformer 120 is grounded.

[0060] In a feasible implementation, when the power system requires reactive power compensation, the reactive power adjustable transformer 140 is used to output a first steplessly adjustable voltage; when the power system requires grounding compensation, the arc extinguishing selection switch 130 is used to close the phase switch corresponding to the grounding fault phase, and the arc extinguishing adjustable transformer 120 is used to output a second steplessly adjustable voltage.

[0061] It should be noted that the reactive power adjustable transformer 140 and the arc extinguishing adjustable transformer 120 are both continuously adjustable, and correspondingly, the first steplessly adjustable voltage and the second steplessly adjustable voltage are also both continuously adjustable. The first steplessly adjustable voltage and the second steplessly adjustable voltage can be adjusted in real time by the operator according to the actual conditions of reactive power compensation and grounding compensation, and no limitation is made here.

[0062] In some embodiments, when the power system requires reactive power compensation, the reactive power adjustable transformer 140 can be adjusted to output a first steplessly adjustable voltage so that the reactive power output by the reactive compensation capacitor 160 reaches the reactive power compensation amount required for reactive power compensation of the power system after passing through the series inductor 150, the reactive power adjustable transformer 140 and the integrated transformer in sequence.

[0063] In some embodiments, when the power system requires arc extinguishing compensation, the phase switch corresponding to the ground fault phase in the arc extinguishing selection switch 130 can be closed, and the arc extinguishing adjustable transformer 120 can be adjusted to output a second steplessly adjustable voltage, so that the second steplessly adjustable voltage reaches the grounding compensation amount required for the power system to perform grounding compensation after passing through the arc extinguishing selection switch 130 and the integrated transformer in sequence.

[0064] It should be particularly noted that, since the power system may require reactive compensation and arc-extinguishing compensation at the same time, the reactive power adjustable transformer 140 outputs a first stepless adjustable voltage and the arc-extinguishing adjustable transformer 120 outputs a second stepless adjustable voltage at the same time, so as to realize reactive compensation and arc-extinguishing compensation at the same time.

[0065] In the embodiment of the present application, the system of the present application can realize reactive power compensation and grounding compensation at the same time through reasonable design, so that there is no need to exit reactive power compensation when performing grounding compensation, thus avoiding overly complicated protection actions and causing power frequency resonant transient overvoltage, and also has fast response arc extinguishing capability and reactive power compensation capability.

[0066] In addition, the system of the present application also has the following advantages: the first stepless adjustable voltage output by the reactive power adjustable transformer 140 and the second stepless adjustable voltage output by the arc extinguishing adjustable transformer 120 are both continuously adjustable, so that they can be adjusted according to the actual needs of reactive power compensation and arc extinguishing compensation to achieve the purpose of precise compensation; by adopting the reactive power compensation capacitor 160 as the output source of reactive power compensation, not only can full reactive power compensation be achieved, but also harmonic elimination can be achieved to avoid overvoltage damage to equipment; since the system is a fusion system of reactive power compensation device and arc extinguishing device, its operation, maintenance, construction cost and losses are relatively low.

[0067] In order to facilitate further understanding, the present application provides an exemplary specific wiring method of the integrated grounding transformer 110, the reactive power adjustable transformer 140, the series reactor 150, the reactive power compensation capacitor 160, the arc extinguishing adjustable transformer 120 and the arc extinguishing selection switch 130. Figure 1 , see Figure 2 , which is a schematic diagram of a power quality management fusion system in an embodiment of the present application Figure 2 The schematic diagram shows the specific wiring method of the integrated grounding transformer 110, the reactive power adjustable transformer 140, the series inductor 150, the reactive power compensation capacitor 160, the arc extinguishing adjustable transformer 120 and the arc extinguishing selection switch 130.

[0068] based on Figure 1 , see Figure 3 , which is a schematic diagram of a power quality management fusion system in an embodiment of the present application Figure 3 The system also includes an integrated controller 310.

[0069] The integrated controller 310 is respectively connected to the reactive power adjustable transformer 140 , the arc extinguishing adjustable transformer 120 , and the arc extinguishing selection switch 130 .

[0070] In a feasible implementation, when the power system requires reactive power compensation, the integrated controller 310 is used to determine the first stepless adjustable voltage based on the current active power and the current reactive power of the power system, and the rated capacity and the rated voltage of the reactive compensation capacitor 160, and control the reactive adjustable transformer 140 to output the first stepless adjustable voltage; when the power system requires grounding compensation, the integrated controller 310 is used to determine the grounding fault phase and the second stepless adjustable voltage, and control the arc extinguishing selection switch 130 to close the phase switch corresponding to the grounding fault phase, and control the arc extinguishing adjustable transformer 120 to output the second stepless adjustable voltage.

[0071] It should be noted that the rated voltage of the reactive compensation capacitor 160 of the present application is equal to the rated output voltage of the reactive adjustable transformer 140. Therefore, in some embodiments, when the power system requires reactive compensation, the integrated controller 310 can also be used to determine the first steplessly adjustable voltage based on the current active power and current reactive power of the power system, the rated capacity of the reactive compensation capacitor 160, and the rated output voltage of the reactive adjustable transformer 140.

[0072] In the embodiment of the present application, by introducing the integrated controller 310, it is possible to intelligently determine the optimal stepless adjustable voltage value based on the real-time operating status of the power system, namely, active power, reactive power, rated capacity and voltage of the reactive compensation capacitor 160 and other information, thereby ensuring the accuracy of reactive compensation and grounding compensation.

[0073] In addition, the integrated controller 310 can automatically control the reactive power adjustable transformer 140 and the arc extinguishing adjustable transformer 120, as well as the arc extinguishing selection switch 130, to achieve automatic operation without human intervention, thereby improving system efficiency and reliability.

[0074] In a feasible implementation, the capacity of the integrated grounding transformer 110 in the above embodiment is greater than or equal to the sum of the capacities of the reactive power adjustable transformer 140 and the arc-extinguishing adjustable transformer 120, the capacity of the reactive power adjustable transformer 140 is greater than or equal to the reactive capacity required for reactive power compensation of the power system, and the capacity of the arc-extinguishing adjustable transformer 120 is greater than or equal to 3 times the maximum capacity required for grounding compensation of the power system.

[0075] In the embodiment of the present application, by setting the capacity of the integrated grounding transformer 110 to be greater than or equal to the sum of the capacities of the reactive power adjustable transformer 140 and the arc extinguishing adjustable transformer 120, it is possible to ensure that both reactive compensation and grounding compensation can achieve full compensation, and it is also possible to ensure that the equipment is not damaged due to overload during grounding compensation and reactive power compensation; by setting the capacity of the reactive power adjustable transformer 140 to be greater than or equal to the reactive capacity required for reactive power compensation of the power system, it is possible to ensure that the system can meet the reactive power compensation requirements of the power system and improve the efficiency of the power grid; by setting the capacity of the arc extinguishing adjustable transformer 120 to be greater than or equal to 3 times the maximum capacity required for grounding compensation of the power system, it is possible to ensure that the system can meet the grounding compensation requirements of the power system and ensure that the system can respond quickly when a grounding fault occurs, extinguish the arc and avoid transient overvoltage from causing harm to the equipment.

[0076] In a feasible implementation, the reactive power compensation capacitor 160 in the above embodiment adopts a star connection mode or a triangle connection mode.

[0077] In an embodiment of the present application, by connecting the reactive compensation capacitor 160 using a star connection method or a triangle connection method, the grounding resistance of the system can be effectively reduced, the overall stability and reliability of the power grid can be improved, and at the same time, the adverse effects caused by the characteristics of the reactive compensation capacitor 160's own capacitance can be avoided.

[0078] In a second aspect, the present application provides a comprehensive control method for a power quality management fusion system.

[0079] See also Figure 4 , is a schematic diagram of a comprehensive control method for a power quality management fusion system in an embodiment of the present application, the method is applied to a system as in any one of the first aspects, the method comprising:

[0080] Step 410: Acquire the current active power and current reactive power of the power system, and the rated capacity and rated voltage of the reactive compensation capacitor.

[0081] It should be noted that the rated voltage of the reactive compensation capacitor of the present application is equal to the rated output voltage of the reactive adjustable transformer. Therefore, in some embodiments, when the power system requires reactive compensation, the integrated controller can also be used to determine the first steplessly adjustable voltage based on the current active power and current reactive power of the power system, the rated capacity of the reactive compensation capacitor, and the rated output voltage of the reactive adjustable transformer.

[0082] Step 420: When the power system requires reactive power compensation, determine the first steplessly adjustable voltage according to the current active power, the current reactive power, the rated capacity and the rated voltage, and control the reactive power adjustable transformer in the system to output the first steplessly adjustable voltage;

[0083] Regarding the method for determining the first steplessly adjustable voltage, in some embodiments, the current power factor of the power system can be determined based on the current active power and the current reactive power, and then the current reactive compensation amount can be determined based on the current power factor. Finally, the first steplessly adjustable voltage can be determined based on the current reactive compensation amount combined with the rated capacity and the rated voltage.

[0084] Step 430: When the power system requires grounding compensation, determine the grounding fault phase and the second stepless adjustable voltage, and control the arc extinguishing selection switch in the system to close the phase switch corresponding to the grounding fault phase, and the arc extinguishing adjustable transformer in the control system to output the second stepless adjustable voltage.

[0085] As for the method for determining the ground fault phase, some existing methods for determining the ground fault phase may be adopted, and this application does not limit this.

[0086] Regarding the manner of determining the second continuously variable voltage, in some embodiments, the second continuously variable voltage may be determined according to the line voltage of the three-phase bus of the power system.

[0087] In an embodiment of the present application, by acquiring real-time active power, reactive power and rated parameters of the reactive compensation capacitor, the optimal first stepless adjustable voltage is intelligently determined to ensure accurate reactive compensation and improve grid efficiency. By accurately identifying the ground fault phase and determining a suitable second stepless adjustable voltage, ground compensation is quickly achieved, transient overvoltages are eliminated, and equipment safety is ensured.

[0088] In addition, this method does not require human intervention, and the system can run automatically, improving operational efficiency and reliability.

[0089] In a feasible implementation, step 420 in the above embodiment determines the first steplessly adjustable voltage based on the current active power, the current reactive power, the rated capacity and the rated voltage, including: obtaining a power factor threshold; determining the first steplessly adjustable voltage based on the power factor threshold, the current active power, the current reactive power, the rated capacity and the rated voltage.

[0090] The power factor threshold is the minimum power factor allowed by the power system operating conditions and safety requirements, and can be set in advance by the operator according to actual conditions.

[0091] In some embodiments, the current power factor of the power system can be determined based on the current active power and the current reactive power, and then the current reactive compensation amount can be determined based on the current power factor and the power threshold factor, and finally the first steplessly adjustable voltage can be determined based on the current reactive compensation amount combined with the rated capacity and the rated voltage.

[0092] In an embodiment of the present application, by setting a power factor threshold, the reactive compensation strategy is made more accurate and intelligent, that is, the power factor threshold is obtained. When the power factor of the system is lower than the power factor threshold, the required reactive compensation amount is calculated based on information such as the current active power, reactive power, rated capacity and rated voltage, so as to adjust the first stepless adjustable voltage output by the reactive adjustable transformer according to the reactive compensation amount, so that the system power factor is increased to the power factor threshold. Compared with the existing determination method, it is more precise and can avoid over-compensation or under-compensation, thereby improving the efficiency of the power grid and stabilizing the system operation.

[0093] In a feasible implementation, the first steplessly adjustable voltage is determined according to the power factor threshold, the current active power, the current reactive power, the rated capacity and the rated voltage in the above embodiment, including:

[0094] Using the formula determining a first steplessly adjustable voltage;

[0095] Among them, U1 is the first stepless adjustable voltage, U e is the rated voltage, P is the current active power, λ TH is the power factor threshold, Q e is the rated capacity, and Q is the current reactive power.

[0096] In the embodiments of the present application, a rigorous calculation formula for the first steplessly adjustable voltage is provided from a mathematical perspective. The accuracy of the calculated first steplessly adjustable voltage can be ensured from the rigor of mathematical logic, and the above calculation formula is preferably shown to provide reference, understanding and calculation for technical personnel.

[0097] In addition, by adopting the calculation formula of the first steplessly adjustable voltage preferably provided in the above-mentioned application to calculate the first steplessly adjustable voltage, it can ensure that the reactive compensation amount is accurately controlled under the premise of meeting the power factor threshold, thereby improving the automation degree and control accuracy of the system.

[0098] Furthermore, through formula calculation, the system can automatically adjust the reactive power compensation voltage according to the real-time current and power data to achieve the optimal power factor control effect, avoiding the errors caused by manual experience and parameter adjustment.

[0099] In a feasible implementation, the method in the above embodiment also includes: obtaining a power factor threshold; determining a current power factor based on current active power and current reactive power; and determining that the power system requires reactive power compensation when the current power factor is less than the power factor threshold.

[0100] It should be noted that by setting the power factor threshold, the power factor of the power system can be monitored in real time. When the power factor of the system is lower than the preset power factor threshold, the system will determine that reactive power compensation is required, and then adjust the first stepless adjustable voltage output by the reactive power adjustable transformer to improve the power factor of the system so that it reaches the set safe operating range.

[0101] In the embodiment of the present application, by setting the power factor threshold, the rough control of reactive power compensation based solely on preset parameters is avoided. Instead, dynamic adjustment is performed according to real-time data. Through precise power factor control, the grid voltage drop caused by too low power factor can be effectively avoided, and possible grid shaking and equipment failure can be prevented.

[0102] In a feasible implementation, step 430 in the above embodiment, determining the second continuously variable voltage, includes: obtaining an average value of line voltages of three-phase buses of the power system; and determining the second continuously variable voltage according to the average value.

[0103] In some embodiments, the present application preferably adopts the average value Times is used as the second continuously variable voltage; of course, in other embodiments, the average value can also be used as the second continuously variable voltage.

[0104] In an embodiment of the present application, by obtaining the average value of the three-phase bus line voltage of the power system, the voltage that needs to be compensated during a ground fault can be judged more quickly, and then the second steplessly adjustable voltage can be determined based on the average value to ensure the accuracy and efficiency of arc extinguishing compensation. Compared with the existing method, this method is more scientific and accurate, and can effectively improve the system's power quality management capabilities.

[0105] In a feasible implementation, the method in the above embodiment further includes: acquiring a current grounding state of the power system; and determining that the power system needs grounding compensation when the current grounding state is a grounding fault.

[0106] In an embodiment of the present application, by acquiring the real-time grounding status of the power system, the occurrence of a grounding fault can be accurately identified, thereby determining whether grounding compensation needs to be performed. This real-time monitoring and judgment mechanism can avoid unnecessary grounding compensation operations in non-grounding fault situations, thereby improving the efficiency and stability of the system.

[0107] In addition, timely monitoring of ground faults can also effectively reduce the risk of overvoltage caused by ground faults and protect the safe operation of power equipment.

[0108] In order to fully verify the effectiveness and feasibility of this application, this application selected the professional power system simulation software PSCAD / EMTDC, and carefully constructed a 10kV medium-voltage power grid simulation model according to the actual situation, including:

[0109] 1. A main transformer is configured, and its performance parameters are set according to the operating standards and safety specifications of the power system to ensure the stable operation of the power grid and the reasonable conversion of voltage levels. In order to simulate the complex characteristics of the real power grid, a Zny11 type integrated grounding transformer and a three-phase autovoltage regulator are used as reactive adjustable transformers for simulation.

[0110] 2. According to the actual needs of the power grid, the medium voltage grid voltage level is set to 10kV, the total line capacitance to ground is 10.59μF, the voltage transformation ratio of the integrated grounding transformer is 25, the rated voltage of the secondary side of the integrated grounding transformer is 0.4kV, the rated voltage of the reactive adjustable transformer is 0.4kV, the output voltage of the reactive adjustable transformer is 0-0.4kV adjustable, and the rated capacity of the reactive compensation capacitor group is 1MVar.

[0111] 3. Taking reactive power compensation as an example, simulation verification is performed: the current active power and reactive power of the power system are set to 1MW and 0.75MVAr respectively, the current power factor of the power system is set to 0.8, the power factor threshold is set to 0.95, and the first stepless adjustable voltage of the reactive power adjustable transformer is determined to be 0.26kV based on the system active power, reactive power, power factor threshold, rated capacity of reactive compensation capacitor and rated voltage of reactive power adjustable transformer. Figure 5 , which is a waveform diagram of the reactive power and active power of the power system during the simulation verification in the embodiment of the present application. The diagram shows that at 0.2s of the simulation, the reactive adjustable transformer, the series inductor and the reactive compensation capacitor are put into use for reactive compensation, so that the reactive power of the power system is reduced and the power factor is increased from 0.8 to 0.95, achieving the purpose of improving the power factor and improving the power quality. In addition, the transient process of reactive regulation is very short and the disturbance to the normal operation of the system is not obvious, which is sufficient to prove the effect of the present application.

[0112] In a third aspect, the present application provides a comprehensive control device for a power quality management fusion system.

[0113] See also Figure 6 , is a schematic diagram of an integrated control device of a power quality management fusion system in an embodiment of the present application, the device is applied to a system as in any one of the first aspect, the device 610 includes:

[0114] An acquisition module 611 is used to acquire the current active power and the current reactive power of the power system, and the rated capacity and the rated voltage of the reactive compensation capacitor;

[0115] The reactive power compensation module 612 is used to determine the first steplessly adjustable voltage according to the current active power, the current reactive power, the rated capacity and the rated voltage when the power system needs reactive power compensation, and control the reactive power adjustable transformer in the system to output the first steplessly adjustable voltage;

[0116] The grounding compensation module 613 is used to determine the grounding fault phase and the second stepless adjustable voltage when the power system needs grounding compensation, and control the arc extinguishing selection switch in the system to close the phase switch corresponding to the grounding fault phase, and the arc extinguishing adjustable transformer in the system to output the second stepless adjustable voltage.

[0117] In the embodiment of the present application, the relevant contents of the acquisition module 611, the reactive power compensation module 612 and the grounding compensation module 613 can be found in Figure 4 The contents in the illustrated embodiment will not be described in detail here.

[0118] It should be noted that the device 610 of the present application also includes some other modules. It can be understood that the method of the present application and the device 610 have a one-to-one correspondence. Therefore, some other modules of the device 610 of the present application are the contents corresponding to the method of the present application in the above-mentioned embodiment.

[0119] In an embodiment of the present application, by acquiring real-time active power, reactive power and rated parameters of the reactive compensation capacitor, the optimal first stepless adjustable voltage is intelligently determined to ensure accurate reactive compensation and improve grid efficiency. By accurately identifying the ground fault phase and determining a suitable second stepless adjustable voltage, ground compensation is quickly achieved, transient overvoltages are eliminated, and equipment safety is ensured.

[0120] In addition, this method does not require human intervention, and the system can run automatically, improving operational efficiency and reliability.

[0121] In a fourth aspect, the present application further provides a computer-readable storage medium storing a computer program. When the computer program is executed by the integrated controller, the integrated controller executes an integrated control method for a power quality management fusion system in the above method embodiment.

[0122] In a fifth aspect, the present application further provides a computer device, including a memory and an integrated controller, wherein the memory stores a computer program, and when the computer program is executed by the integrated controller, the integrated controller executes an integrated control method for a power quality management fusion system in the above method embodiment.

[0123] Figure 7 The internal structure diagram of a computer device in some embodiments is shown. The computer device may be a terminal, a server, or a gateway. Figure 7As shown, the computer device includes an integrated controller, a memory and a network interface connected via a system bus.

[0124] The memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium of the computer device stores an operating system and may also store a computer program. When the computer program is executed by the integrated controller, the integrated controller can implement each step in the above method embodiment. The internal memory may also store a computer program. When the computer program is executed by the integrated controller, the integrated controller can implement each step in the above method embodiment. Those skilled in the art can understand that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0125] A person skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing related hardware through a computer program. The program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods.

[0126] Among them, any reference to memory, storage, database or other media used in the embodiments provided in the present application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synch li nk) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0127] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0128] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A power quality management fusion system, characterized in that: The system includes a comprehensive grounding transformer, a reactive power adjustable transformer, a series reactor, a reactive power compensation capacitor, an arc extinguishing adjustable transformer and an arc extinguishing selection switch; The primary side of the integrated grounding transformer is connected to the three-phase busbar of the power system in three phases, and the secondary side of the integrated grounding transformer is respectively connected to the primary side of the reactive power adjustable transformer and the primary side of the arc-extinguishing adjustable transformer in three phases; the secondary side of the reactive power adjustable transformer is connected to one side of the series reactor in three phases, and the other side of the series reactor is connected to the reactive power compensation capacitor in three phases; the secondary side of the arc-extinguishing adjustable transformer is connected to one side of the arc-extinguishing selection switch in three phases, and the other side of the arc-extinguishing selection switch is short-circuited with the neutral point of the primary side of the integrated grounding transformer, and the neutral point of the secondary side of the arc-extinguishing adjustable transformer is grounded; In the case where the power system requires reactive power compensation, the reactive power adjustable transformer is used to output a first steplessly adjustable voltage; In the case where the power system requires grounding compensation, the arc extinguishing selection switch is used to close the phase switch corresponding to the grounding fault phase, and the arc extinguishing adjustable transformer is used to output a second steplessly adjustable voltage.

2. The system according to claim 1, characterized in that The system also includes an integrated controller; The integrated controller is respectively connected to the reactive power adjustable transformer, the arc extinguishing adjustable transformer, and the arc extinguishing selection switch; In the case where the power system requires reactive power compensation, the integrated controller is used to determine the first steplessly adjustable voltage according to the current active power and the current reactive power of the power system, and the rated capacity and the rated voltage of the reactive compensation capacitor, and control the reactive adjustable transformer to output the first steplessly adjustable voltage; When the power system requires grounding compensation, the integrated controller is used to determine the grounding fault phase and the second steplessly adjustable voltage, and control the arc extinguishing selection switch to close the phase switch corresponding to the grounding fault phase, and control the arc extinguishing adjustable transformer to output the second steplessly adjustable voltage.

3. The system according to claim 1, characterized in that The capacity of the integrated grounding transformer is greater than or equal to the sum of the capacities of the reactive power adjustable transformer and the arc-extinguishing adjustable transformer, the capacity of the reactive power adjustable transformer is greater than or equal to the reactive capacity required for reactive power compensation of the power system, and the capacity of the arc-extinguishing adjustable transformer is greater than or equal to three times the maximum capacity required for grounding compensation of the power system.

4. The method according to claim 1, characterized in that: The reactive power compensation capacitor adopts a star connection mode or a triangle connection mode.

5. A comprehensive control method for a power quality management fusion system, the method being applied to a system as claimed in any one of claims 1 to 4, characterized in that: The method comprises: Acquiring the current active power and the current reactive power of the power system, as well as the rated capacity and the rated voltage of the reactive compensation capacitor; In the case where the power system requires reactive power compensation, determining a first steplessly adjustable voltage according to the current active power, the current reactive power, the rated capacity and the rated voltage, and controlling the reactive power adjustable transformer in the system to output the first steplessly adjustable voltage; In the case where the power system requires grounding compensation, the grounding fault phase and the second steplessly adjustable voltage are determined, and the arc extinguishing selection switch in the system is controlled to close the phase switch corresponding to the grounding fault phase, and the arc extinguishing adjustable transformer in the system is controlled to output the second steplessly adjustable voltage.

6. The method according to claim 5, characterized in that The determining of the first steplessly adjustable voltage according to the current active power, the current reactive power, the rated capacity and the rated voltage comprises: Get the power factor threshold; The first steplessly adjustable voltage is determined according to the power factor threshold, the current active power, the current reactive power, the rated capacity and the rated voltage.

7. The method according to claim 6, characterized in that The determining the first steplessly adjustable voltage according to the power factor threshold, the current active power, the current reactive power, the rated capacity and the rated voltage includes: Using the formula determining the first steplessly adjustable voltage; Among them, U1 is the first steplessly adjustable voltage, U e is the rated voltage, P is the current active power, λ TH is the power factor threshold, Q e is the rated capacity, and Q is the current reactive power.

8. The method according to claim 5, characterized in that The method further comprises: Get the power factor threshold; Determining a current power factor according to the current active power and the current reactive power; When the current power factor is less than the power factor threshold, it is determined that the power system requires reactive power compensation.

9. The method according to claim 5, characterized in that Determining the second steplessly adjustable voltage includes: Obtaining an average value of line voltages of three-phase buses of the power system; The second steplessly adjustable voltage is determined according to the average value.

10. The method according to claim 5, characterized in that The method further comprises: Acquiring a current grounding state of the power system; When the current grounding state is a grounding fault, it is determined that the power system needs grounding compensation.

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