Efficient switching-on operation overvoltage control method

Abstract

The invention discloses a high-efficiency switching-on operation overvoltage control method, which comprises the steps of monitoring a line in real time, obtaining waveform characteristics of current line voltage, calculating a waveform zero point position at a switching-on moment according to the obtained line voltage characteristics, and dynamically adjusting a switching-on time sequence; smooth line voltages of different voltage levels are established step by step, bidirectional current buffer control is carried out in the switching-on process, and the rising rate of the current is adjusted; setting and monitoring a current threshold value during closing, and implementing high-current cut-off before the current reaches a preset value; asymmetrically controlling the closing phase of each phase of the three-phase closing operation; and monitoring the attenuation trend of the residual voltage, and triggering the closing operation when the residual voltage is reduced to a preset safety range. According to the invention, the service life of power equipment is effectively prolonged while the switching-on operation efficiency is improved, and a safe and efficient overvoltage control scheme is provided for a complex power system.

Description

Technical Field

[0001] The present invention relates to the technical field of overvoltage control, and in particular to a high-efficiency closing operation overvoltage control method. Background Art

[0002] In the power system, the closing operation is an inevitable control process of power equipment, but it is easy to generate transient overvoltage and current mutation at the moment of closing, especially for high inductive loads and long-distance lines, the instantaneous voltage peak superposition effect is more significant. Traditional overvoltage control mostly relies on fixed buffer devices or simple delay control, but under complex load conditions, these methods are difficult to achieve precise control of closing transients, and cannot effectively suppress the overvoltage caused by closing, which in turn affects the stability of the power grid and the service life of the equipment. With the increase in the complexity of the power system and the increase in the types of loads, the existing technology has shown limitations in closing transient control, and it is difficult to meet the high-precision requirements of dynamic voltage control. There is an urgent need for a technical method that can adapt to a variety of load conditions and improve the overvoltage control effect of the closing process. Summary of the invention

[0003] In view of the above existing problems, the present invention is proposed.

[0004] Therefore, the present invention provides an efficient closing operation overvoltage control method, which aims to solve the problems of power grid instability and equipment damage caused by transient overvoltage and current mutation in the existing closing operation, and proposes an overvoltage control method that dynamically adjusts the closing timing, closes in stages, and combines bidirectional current buffering with high current cutoff. This technology monitors the zero point of the voltage waveform in real time, analyzes the current characteristics, and dynamically sets the closing time and delay for different loads to achieve control and precise cutoff of the current rise rate and avoid the superposition effect of transient overvoltage. By optimizing voltage distribution and phase control, the present invention realizes dynamic management of the closing process under various load conditions, ensuring the safety of the closing operation and the stability of the power grid.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions, a high-efficiency closing operation overvoltage control method, comprising:

[0006] Monitor the instantaneous value, residual voltage and initial current of the line voltage in real time, obtain the waveform characteristics of the current line voltage, calculate the waveform zero point position at the closing time based on the obtained line voltage characteristics, and dynamically adjust the closing timing;

[0007] Implement multi-stage closing operation, gradually establish different voltage levels to smooth the line voltage, and perform bidirectional current buffer control to adjust the current rise rate during the closing process;

[0008] Set and monitor the current threshold when closing the circuit breaker, and implement high current cutoff before the current reaches the preset value;

[0009] Asymmetric control of the closing phase of each phase of the three-phase closing operation to optimize the phase interval;

[0010] Monitor the attenuation trend of the residual voltage and trigger the closing operation when the residual voltage drops to a preset safety range.

[0011] As a preferred solution of the high-efficiency closing operation overvoltage control method of the present invention, the dynamic adjustment of the closing timing includes real-time monitoring of the positive and negative peaks and zero point positions in the line voltage waveform to obtain the change trend of the voltage waveform, and the voltage monitoring device transmits the collected instantaneous voltage data to the control unit;

[0012] The control unit calculates the voltage zero point and peak position of each cycle based on the real-time waveform state and load characteristics of the line voltage, determines the extreme points of voltage fluctuation, and determines the closing time. The control unit analyzes the voltage waveform trend through a specific algorithm, predicts the time point when the voltage is about to reach zero, and matches the closing instruction with this time point to ensure that the closing operation is highly synchronized with the voltage zero point. The control unit adaptively sets the adjustment parameters of the closing timing based on the impedance characteristics of different loads and the line status.

[0013] As a preferred solution of the high-efficiency closing operation overvoltage control method of the present invention, wherein: the multi-stage closing operation includes applying a low voltage at the initial closing, as a start-up stage, the initial voltage level is set to 30% to 50% of the target operating voltage, and the line and load equipment are pre-adjusted;

[0014] After closing the circuit breaker during the startup phase, the control unit gradually increases the closing voltage at preset time intervals. The specific time intervals and increments are set based on the line length, capacitance, inductance parameters, and load characteristics, including the type and value of resistive or inductive loads.

[0015] As a preferred solution of the efficient closing operation overvoltage control method described in the present invention, the multi-stage closing operation includes: in each stage of closing voltage increase, the control unit ensures that the voltage rises step by step to the next set voltage value until the target operating voltage is reached, and the control unit continuously monitors the transient fluctuations in the voltage rise process, and adjusts the voltage increment and rising speed in real time according to the current response of the line, so that the line gradually transitions to the full voltage closing state.

[0016] As a preferred solution of the efficient closing operation overvoltage control method described in the present invention, the bidirectional current buffering control includes, at the moment of closing, detecting the forward current and reverse current components in the circuit, and setting different buffering factors to control the current rising rate.

[0017] As a preferred solution of the efficient closing operation overvoltage control method described in the present invention, the bidirectional current buffering control includes setting the buffering factor based on the impedance characteristics of the inductive load and the transient response parameters of the line, and adjusting the change rate of the forward and reverse currents in segments.

[0018] As a preferred solution of the efficient closing operation overvoltage control method described in the present invention, the high current cutoff includes real-time monitoring of the current value in the line at the closing moment, and setting a current threshold according to the inductive load characteristics. When the control unit detects that the current value reaches the preset threshold, it immediately triggers the disconnection operation to quickly interrupt the closing process. The current threshold is set by a dynamic adjustment mechanism, and the specific adjustment basis is the inductance, load impedance and line transient response speed.

[0019] As a preferred solution of the efficient closing operation overvoltage control method described in the present invention, the high current cutoff includes: the control unit pre-loads a dynamic adjustment algorithm for various inductive loads, calculates a suitable current threshold according to real-time load conditions, and starts a cutoff instruction when the current rises to the threshold, thereby interrupting the current immediately before the current waveform approaches the peak value.

[0020] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and is characterized in that when the processor executes the computer program, steps of a method for controlling overvoltage in an efficient closing operation are implemented.

[0021] A computer-readable storage medium having a computer program stored thereon, characterized in that when the computer program is executed by a processor, the steps of a method for efficiently controlling overvoltage in closing operation are implemented.

[0022] Beneficial effects of the present invention: The present invention effectively reduces transient overvoltages during the closing process and reduces system shocks caused by current mutations by introducing dynamic adjustment of closing timing and multi-stage closing operations. At the same time, combined with bidirectional current buffering control and high current cutoff, the current can be accurately cut off before the current reaches the set threshold, thereby achieving optimized control of the current steepness. This technology can be adaptively adjusted under a variety of load conditions, overcoming the limitations of traditional static buffering methods, making the closing operation smoother and more reliable. While improving the efficiency of closing operations, the present invention effectively extends the service life of power equipment, providing a safe and efficient overvoltage control solution for complex power systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0024] Figure 1 A schematic flow chart of a method for controlling overvoltage in a high-efficiency closing operation is provided as an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0026] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0027] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0028] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0029] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0030] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] Example 1, reference Figure 1 , which is the first embodiment of the present invention, provides an efficient closing operation overvoltage control method, comprising:

[0032] S1: Monitor the instantaneous value, residual voltage and initial current of the line voltage in real time, obtain the waveform characteristics of the current line voltage, calculate the waveform zero point position at the closing time according to the obtained line voltage characteristics, and dynamically adjust the closing timing.

[0033] S2: Implement multi-stage closing operation, gradually establish different voltage levels to smooth the line voltage, and perform bidirectional current buffer control during the closing process to adjust the current rise rate.

[0034] S3: Set and monitor the current threshold when closing the circuit breaker, and implement high current cutoff before the current reaches the preset value.

[0035] S4: Asymmetric control is performed on the closing phase of each phase of the three-phase closing operation to optimize the phase interval.

[0036] S5: Monitor the attenuation trend of the residual voltage and trigger the closing operation when the residual voltage drops to a preset safety range.

[0037] The dynamic adjustment of the closing timing includes real-time monitoring of the positive and negative peaks and zero position in the line voltage waveform to obtain the change trend of the voltage waveform, and the voltage monitoring device transmits the collected instantaneous voltage data to the control unit;

[0038] The control unit calculates the voltage zero point and peak position of each cycle based on the real-time waveform state and load characteristics of the line voltage, determines the extreme points of voltage fluctuation, and determines the closing time. The control unit analyzes the voltage waveform trend through a specific algorithm, predicts the time point when the voltage is about to reach zero, and matches the closing instruction with this time point to ensure that the closing operation is highly synchronized with the voltage zero point. The control unit adaptively sets the adjustment parameters of the closing timing based on the impedance characteristics of different loads and the line status.

[0039] The multi-stage closing operation includes applying a low voltage at the initial closing as a start-up stage, with the initial voltage level set to 30% to 50% of the target operating voltage to pre-adjust the line and load equipment;

[0040] After closing the circuit breaker during the startup phase, the control unit gradually increases the closing voltage at preset time intervals. The specific time intervals and increments are set based on the line length, capacitance, inductance parameters, and load characteristics, including the type and value of resistive or inductive loads.

[0041] The multi-stage closing operation includes: in each stage of closing voltage increase, the control unit ensures that the voltage rises step by step to the next set voltage value until the target operating voltage is reached, the control unit continuously monitors the transient fluctuations in the voltage rise process, and adjusts the voltage increment and rising speed in real time according to the current response of the line, so that the line gradually transitions to the full voltage closing state.

[0042] The bidirectional current buffer control includes, at the moment of closing the switch, detecting the forward current and reverse current components in the circuit, and setting different buffer factors to control the rising rate of the current.

[0043] The buffer factor is set based on the impedance characteristics of the inductive load and the transient response parameters of the line, and the change rate of the forward and reverse currents is adjusted in sections.

[0044] Specifically, assume that the line current i(t) starts to rise at the moment of closing, and define the positive and negative components of the current as i + (t) and i - (t), and introduce the buffer factor α + and α - To control its rising rate:

[0045]

[0046] Among them, f(i,L) is a response function that depends on the inductance L, which is used to indicate the adaptability of the current rise to the inductive load. f(i,L) is expressed as:

[0047]

[0048] Where k is the nonlinear adjustment coefficient, which increases the buffer response in current changes and smoothes transient changes.

[0049] To achieve buffer control of forward and reverse current, the buffer factor α + and α - At the moment of closing, the initial value is set to α 0+ and α 0- , and dynamically adjusts over time according to the following relationship:

[0050] α + (t) = α 0+ ·e -βt

[0051] α- (t) = α 0- ·e -γt

[0052] Among them, β and γ are the forward and reverse current buffer attenuation coefficients respectively. This adjustment method makes the current change steepest and the buffering effect strongest at the initial stage of closing, and gradually weakens over time.

[0053] The actual composite current i(t) in the line is obtained by superimposing the positive and reverse current components and is constrained by the buffer control function:

[0054] i(t)=i + (t)+i - (t)

[0055] By controlling α + and α - The dynamic change of i(t) controls the steepness of i(t) to make it transition smoothly under load. Its final form is expressed as:

[0056]

[0057] Compared with the traditional fixed buffer coefficient model, dynamic buffering is performed according to the current directionality and its change rate at the initial stage of closing, so that the current rise steepness is adaptively reduced over time, thereby optimizing the closing response of the inductive load.

[0058] The high current cutoff includes real-time monitoring of the current value in the line at the moment of closing the circuit, and setting a current threshold according to the inductive load characteristics. When the control unit detects that the current value reaches the preset threshold, it immediately triggers the disconnection operation to quickly interrupt the closing process. The current threshold is set by a dynamic adjustment mechanism, and the specific adjustment is based on the inductance, load impedance and transient response speed of the line.

[0059] The high current cutoff includes: the control unit pre-loads a dynamic adjustment algorithm for various inductive loads, calculates a suitable current threshold according to real-time load conditions, and starts a cutoff instruction when the current rises to the threshold, thereby immediately interrupting the current before the current waveform approaches the peak value.

[0060] The asymmetry control includes dynamically controlling the phase delay of the three-phase voltage, combining the transient response characteristics of the line, and realizing an asymmetric phase difference through time delay.

[0061] Specifically, assuming that the power frequency angular frequency of the line is ω, the phase delays of the three-phase closing are θ A ,θ B ,θ C , then the closing time of the three phases is t A ,t B ,t C It is expressed as:

[0062] t A =t0

[0063] t B =t0+Δt AB

[0064] t C =t0+Δt AC

[0065] Among them, t0 is the initial closing time of phase A, Δt AB and Δt AC They are the time delays of phase B and phase C relative to phase A, ensuring that the three-phase closing operation is asymmetric in time.

[0066] In order to ensure that the three-phase closing phases are staggered to reduce the transient overvoltage superposition, the relationship between the phase angle difference Δθ is defined as follows:

[0067] Δθ AB =ω·Δt AB

[0068] Δθ AC =ω·Δt AC

[0069] Among them, Δθ AB and Δθ AC The phase difference between phases B and C and phase A is dynamically adjusted by Δt AB and Δt AC , keeping the phases of each phase staggered.

[0070] Furthermore, according to the load characteristics and transient response, the phase delay of the three phases is optimized to achieve the best voltage distribution. Define the load adjustment factor k for each phase A , k B , k C , then the optimization model of time delay is:

[0071] Δt AB =k B ·T / 3

[0072] Δt AC =k C ·T / 3

[0073] in is the period of the system voltage. Load adjustment factor k B and k C Based on the impedance characteristics of the line and load, the phase delay of the three-phase closing is dynamically adjusted to reduce transient overvoltage. By accurately controlling the delay setting of the three phases during the closing process, the phase stagger angle difference is flexibly adjusted to reduce the superposition effect of the instantaneous voltage peak.

[0074] 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 preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0075] Example 2

[0076] The second embodiment of the present invention is different from the first two embodiments in that:

[0077] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0078] 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.

[0079] 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.

[0080] 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 in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0081] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0082] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. An efficient closing operation overvoltage control method, characterized in that: include, Monitor the instantaneous value, residual voltage and initial current of the line voltage in real time, obtain the waveform characteristics of the current line voltage, calculate the waveform zero point position at the closing time based on the obtained line voltage characteristics, and dynamically adjust the closing timing; Implement multi-stage closing operation, gradually establish different voltage levels to smooth the line voltage, and perform bidirectional current buffer control to adjust the current rise rate during the closing process; Set and monitor the current threshold when closing the circuit breaker, and implement high current cutoff before the current reaches the preset value; Asymmetric control of the closing phase of each phase of the three-phase closing operation to optimize the phase interval; Monitor the attenuation trend of the residual voltage and trigger the closing operation when the residual voltage drops to a preset safety range.

2. A high-efficiency closing operation overvoltage control method according to claim 1, characterized in that: The dynamic adjustment of the closing timing includes real-time monitoring of the positive and negative peaks and zero position in the line voltage waveform to obtain the change trend of the voltage waveform, and the voltage monitoring device transmits the collected instantaneous voltage data to the control unit; The control unit calculates the voltage zero point and peak position of each cycle based on the real-time waveform state and load characteristics of the line voltage, determines the extreme points of voltage fluctuation, and determines the closing time. The control unit analyzes the voltage waveform trend through a specific algorithm, predicts the time point when the voltage is about to reach zero, and matches the closing instruction with this time point to ensure that the closing operation is highly synchronized with the voltage zero point. The control unit adaptively sets the adjustment parameters of the closing timing based on the impedance characteristics of different loads and the line status.

3. A high-efficiency closing operation overvoltage control method as claimed in claim 2, characterized in that: The multi-stage closing operation includes applying a low voltage at the initial closing as a start-up stage, with the initial voltage level set to 30% to 50% of the target operating voltage to pre-adjust the line and load equipment; After closing the circuit breaker during the startup phase, the control unit gradually increases the closing voltage at preset time intervals. The specific time intervals and increments are set based on the line length, capacitance, inductance parameters, and load characteristics, including the type and value of resistive or inductive loads.

4. A high-efficiency closing operation overvoltage control method as claimed in claim 3, characterized in that: The multi-stage closing operation includes: in each stage of closing voltage increase, the control unit ensures that the voltage rises step by step to the next set voltage value until the target operating voltage is reached, the control unit continuously monitors the transient fluctuations in the voltage rise process, and adjusts the voltage increment and rising speed in real time according to the current response of the line, so that the line gradually transitions to the full voltage closing state.

5. A high-efficiency closing operation overvoltage control method as claimed in claim 4, characterized in that: The bidirectional current buffer control includes, at the moment of closing the switch, detecting the forward current and reverse current components in the circuit, and setting different buffer factors to control the rising rate of the current.

6. A high-efficiency closing operation overvoltage control method according to claim 5, characterized in that: The bidirectional current buffering control includes setting the buffering factor based on the impedance characteristics of the inductive load and the transient response parameters of the line, and adjusting the change rate of the forward and reverse currents in sections.

7. A high-efficiency closing operation overvoltage control method according to claim 6, characterized in that: The high current cutoff includes real-time monitoring of the current value in the line at the moment of closing the circuit, and setting a current threshold according to the inductive load characteristics. When the control unit detects that the current value reaches the preset threshold, it immediately triggers the disconnection operation to quickly interrupt the closing process. The current threshold is set by a dynamic adjustment mechanism, and the specific adjustment is based on the inductance, load impedance and transient response speed of the line.

8. The high-efficiency closing operation overvoltage control method according to claim 7, characterized in that: The high current cutoff includes: the control unit pre-loads a dynamic adjustment algorithm for various inductive loads, calculates a suitable current threshold according to real-time load conditions, and starts a cutoff instruction when the current rises to the threshold, thereby immediately interrupting the current before the current waveform approaches the peak value.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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