Modeling method, system, device and medium for lightning transient process of diode assembly

Abstract

The present invention discloses a modeling method, system, device and medium for the transient process of lightning strike of a diode component, wherein the method includes: constructing an electrical model framework of the lightning strike time scale of a high-voltage uncontrolled rectifier valve series diode component according to the time scale characteristics of a lightning wave and the overall structural characteristics of a high-voltage uncontrolled rectifier valve; constructing an equivalent model of the power frequency operation of a diode reverse process based on the power frequency steady-state operation time scale; constructing a physical process model of the reverse shutdown of a diode under the action of a lightning strike based on the lightning wave time scale; constructing an electrical model of a high-voltage uncontrolled rectifier valve series diode component through electrical connection; constructing an electrical model of a series diode for the entire process of a lightning strike based on the waveform characteristics of a lightning wave. The present invention constructs a physical model of diode reverse shutdown based on the physical process of a power diode, overcomes the defect that the time scale of the diode junction capacitance equivalent model is much larger than the lightning wave time scale, and can be widely used in the field of modeling of high-voltage uncontrolled rectifier valves.

Description

Technical Field

[0001] The invention relates to the field of high-voltage uncontrolled rectifier valve modeling, and in particular to a modeling method, system, device and medium for a lightning transient process of a diode component. Background Art

[0002] High-voltage uncontrolled rectifier valves (uncontrolled rectifier circuits) are core key components for high-voltage and high-power DC power conversion and transmission, and are widely used in high-voltage DC transmission and DC transmission of offshore wind power. High-voltage uncontrolled rectifier valves contain a large number of semiconductor devices and are typical sensitive devices. They are easily affected by external factors such as short circuits, load switching and lightning strikes, which can cause them to fail and endanger their safe and stable operation. On the other hand, the towers and overhead lines for high-voltage power transmission are relatively high, making high-voltage uncontrolled rectifier valves more susceptible to lightning strikes. The lightning strike process is short and releases huge energy, which requires the high-voltage uncontrolled rectifier valve series diode assembly to withstand severe overvoltage shocks, and even causes the high-voltage uncontrolled rectifier valve to lose its operating ability, resulting in a large amount of economic losses. Therefore, how to analyze the voltage distribution characteristics of the high-voltage uncontrolled rectifier valve series diode assembly under the action of lightning strikes to ensure its safe and stable operation is a research challenge that needs to be solved urgently.

[0003] Lightning strike is one of the common faults in high-voltage power transmission. At present, the research on the series diode components of high-voltage uncontrolled rectifier valves under lightning strikes is still in a blank stage. In view of the time scale of lightning waves, the dynamic characteristics of the series diodes in the high-frequency rectifier system can be used to learn from the dynamic characteristics of the series diodes in the high-frequency rectifier system to carry out the research on the voltage distribution of the series diode components of high-voltage uncontrolled rectifier valves. The model of the series diode components of high-voltage uncontrolled rectifier valves usually adopts the junction capacitance equivalent model, and combines the parasitic capacitance of the series diode to analyze its transient voltage distribution characteristics. However, the junction capacitance of the diode is a simplification of its reverse recovery process on a larger time scale. When the time scale of the system state change is small, the junction capacitance will not be able to explain the reverse shutdown process, which is not conducive to the analysis of the transient voltage distribution of the series diode of the high-voltage uncontrolled rectifier valve. On the other hand, the lightning strike process is short and the energy released is huge. The traditional diode junction capacitance equivalent model cannot be applied to the analysis of nonlinear transient processes under lightning strikes. Summary of the invention

[0004] In order to solve at least one of the technical problems existing in the prior art to a certain extent, the present invention aims to provide a modeling method, system, device and medium for a lightning transient process of a diode assembly.

[0005] The technical solution adopted by the present invention is:

[0006] A modeling method for a transient process of a lightning strike on a diode assembly comprises the following steps:

[0007] According to the characteristics of lightning wave time scale and the overall structural features of high-voltage uncontrolled rectifier valve, the electrical model framework of lightning strike time scale of high-voltage uncontrolled rectifier valve series diode assembly is constructed;

[0008] According to the electrical model framework, the reverse process electrical model of the diode is divided into the reverse process power frequency working electrical model of the diode and the reverse process transient working electrical model of the diode;

[0009] Based on the power frequency steady-state working time scale, an equivalent model of the diode reverse process power frequency working is constructed;

[0010] Based on the lightning wave time scale, a physical process model of diode reverse shutdown under lightning strike is constructed;

[0011] Through electrical connection, an electrical model of a high-voltage uncontrolled rectifier valve in series with a diode assembly is constructed;

[0012] Based on the waveform characteristics of lightning waves, an electrical model of series diodes for the entire lightning impulse process is constructed.

[0013] Furthermore, the waveform of the lightning wave is that the lightning current rises rapidly before the steep wave and drops relatively slowly to a normal current state after the steep wave.

[0014] Furthermore, the power frequency operation equivalent model of the diode reverse process is constructed in a simplified form in which the junction capacitance C is connected in parallel with the diode internal resistance R.

[0015] Furthermore, the construction of a physical process model of diode reverse shutdown under lightning strike includes:

[0016] In the minority carrier depletion stage, the voltage across the diode is maintained at the on-state voltage. Combined with the charge state of the PN junction, the current model flowing through the diode is:

[0017]

[0018]

[0019] q E =(τ+T M )i

[0020] Where i is the current flowing through the diode, qE is the charge on the PN junction, qM is the charge stored at the PN junction boundary, TM is the transfer time, and τ is the carrier lifetime;

[0021] qE is determined by the PN junction material and is expressed as:

[0022]

[0023] Where, v is the diode junction voltage, Is is the diode reverse saturation current, and VTj is the voltage equivalent of temperature;

[0024] In the minority carrier depletion stage, since the diode is in the on state, the current flowing through the diode is also affected by the current of the uncontrolled rectifier valve, so the current flowing through the diode is:

[0025] i=i F +at

[0026] Where a is the current change rate, a = di / dt;

[0027] In the minority carrier depletion stage, qM changes during the current decay process and gradually depletes qE; then in the minority carrier depletion stage, qM is analyzed as:

[0028]

[0029] Within the minority carrier depletion time range, the current changes with slope a, and the process time is:

[0030]

[0031] When in the reverse recovery process, the current is expressed as:

[0032]

[0033] Among them, t3 represents the start time of the reverse recovery phase; the reverse recovery time constant is τ rr , and the carrier lifetime τ and carrier transfer time T M Related, expressed as:

[0034]

[0035] Since when t=I RM / a+t F When the reverse recovery current is:

[0036] I RM / 10

[0037] Then tF is resolved to:

[0038] t F =τ rr log(10)+i RM / a

[0039] The amount of charge during the tS time:

[0040]

[0041] The amount of charge during the time tF is:

[0042] Q F =τ rr i RM

[0043] Q rr =Q S +Q F

[0044] Then the reverse recovery time under the reverse recovery charge constraint is:

[0045]

[0046] Among them, I RM Indicates the amplitude of the maximum reverse current; i RM Indicates the instantaneous value of the maximum reverse current.

[0047] Furthermore, the electrical model of the high-voltage uncontrolled rectifier valve series diode assembly is constructed through electrical connection, including:

[0048] By adopting electrical connection, the diode reverse process models under the same time scale are connected in series to form an electrical model of a high-voltage uncontrolled rectifier valve in series with a diode assembly.

[0049] Furthermore, the diode reverse process models under the same time scale are connected in series, including:

[0050] Connect the equivalent model of the diode reverse process working at power frequency in series; or,

[0051] The physical process model of diode reverse shutdown under lightning strike is connected in series.

[0052] Furthermore, the electrical model of the series diode for the whole process of lightning impulse is constructed based on the waveform characteristics of the lightning wave, including:

[0053] The time scale characteristics of lightning waves are extracted, and the reverse process model of the switching diode is formed to form an electrical model of the series diode for the entire process of lightning impulse.

[0054] Another technical solution adopted by the present invention is:

[0055] A modeling system for a transient process of a lightning strike on a diode assembly, comprising:

[0056] An architecture building module, used to build an electrical model architecture of the lightning strike time scale of a high-voltage uncontrolled rectifier valve series diode component according to the lightning wave time scale characteristics and the overall structural characteristics of the high-voltage uncontrolled rectifier valve;

[0057] A model division module is used to divide the reverse process electrical model of the diode into a reverse process power frequency working electrical model of the diode and a reverse process transient working electrical model of the diode according to the electrical model architecture;

[0058] The power frequency model module is used to construct a power frequency equivalent model of the diode reverse process based on the power frequency steady-state working time scale;

[0059] The lightning model module is used to build a physical process model of diode reverse shutdown under lightning strike based on the lightning wave time scale;

[0060] A series model module is used to construct an electrical model of a high-voltage uncontrolled rectifier valve series diode component through electrical connections;

[0061] The lightning transient module is used to build an electrical model of a series diode for the entire lightning impulse process based on the waveform characteristics of the lightning wave.

[0062] Another technical solution adopted by the present invention is:

[0063] A modeling device for a transient process of a lightning strike of a diode assembly, comprising:

[0064] at least one processor;

[0065] at least one memory for storing at least one program;

[0066] When the at least one program is executed by the at least one processor, the at least one processor implements the above method.

[0067] Another technical solution adopted by the present invention is:

[0068] A computer-readable storage medium stores a program executable by a processor, wherein the program executable by the processor is used to execute the method described above when executed by the processor.

[0069] The beneficial effects of the present invention are as follows: based on the physical process of power diodes, the present invention constructs a diode reverse shutdown physical model of the lightning wave time scale, thereby overcoming the defect that the time scale of the diode junction capacitance equivalent model is much larger than the lightning wave time scale. In addition, the diode reverse shutdown physical model is conducive to analyzing the nonlinear distribution characteristics of the transient process of the lightning overvoltage of the series diode of the high-voltage uncontrolled rectifier valve, which helps to improve the lightning resistance design of the high-voltage uncontrolled rectifier valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the embodiments of the present invention or the drawings of related technical solutions in the prior art are introduced below. It should be understood that the drawings introduced below are only for the convenience of clearly describing some embodiments of the technical solutions of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0071] Figure 1 It is a flow chart of a modeling method for a lightning transient process of a high-voltage uncontrolled rectifier valve connected in series with a diode assembly in an embodiment of the present invention;

[0072] Figure 2 is a schematic diagram of an RC equivalent circuit in an embodiment of the present invention;

[0073] Figure 3 is a schematic diagram of an equivalent circuit of a nonlinear capacitor in an embodiment of the present invention;

[0074] Figure 4 is a schematic diagram of an equivalent circuit of series diodes based on an RC equivalent circuit in an embodiment of the present invention;

[0075] Figure 5 is a schematic diagram of a series diode equivalent circuit of a nonlinear capacitor equivalent circuit in an embodiment of the present invention;

[0076] Figure 6 is a schematic diagram of a lightning current waveform in an embodiment of the present invention;

[0077] Figure 7 Schematic diagram of voltage distribution of steady-state series diodes in an embodiment of the present invention;

[0078] Figure 8 Schematic diagram of voltage distribution of series diodes during a lightning strike transient process in an embodiment of the present invention. DETAILED DESCRIPTION

[0079] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and are not to be construed as limitations of the present invention. For the step numbers in the following embodiments, they are only provided for the convenience of explanation, and the order between the steps is not limited in any way, and the execution order of each step in the embodiment can be adaptively adjusted according to the understanding of those skilled in the art.

[0080] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0081] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0082] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0083] like Figure 1 As shown, this embodiment provides a modeling method for a lightning transient process of a high-voltage uncontrolled rectifier valve in series with a diode assembly, which specifically includes the following steps:

[0084] S1. Construct the electrical model framework of the lightning strike time scale of the high-voltage uncontrolled rectifier valve series diode assembly.

[0085] According to the time scale characteristics of lightning waves and the overall structural features of high-voltage uncontrolled rectifier valves, a lightning strike time scale electrical model framework of high-voltage uncontrolled rectifier valve series diode components is constructed.

[0086] S2. Based on the architecture, the reverse process electrical model of the diode is divided into a reverse process low-frequency working electrical model of the diode and a reverse process transient working electrical model of the diode.

[0087] The high-voltage uncontrolled rectifier valve series diode assembly in this embodiment includes three series diodes. In this embodiment, the reverse process refers to the process in which the diode gradually changes from forward conduction to reverse cutoff after the forward voltage at both ends of the diode is changed to a reverse voltage.

[0088] S3. Construct an equivalent model of the diode's reverse process working at industrial frequency.

[0089] like Figure 2 As shown in the figure, the equivalent model of the low-frequency operation of the diode reverse process can be simplified in the form of a junction capacitance C connected in parallel with the diode internal resistance R.

[0090] S4. Construct a physical process model of diode reverse shutdown under lightning strike.

[0091] The physical process model of the diode reverse shutdown under the action of lightning can be simplified to a nonlinear capacitance effect according to the shutdown process. The modeling steps are as follows:

[0092] S41. In the minority carrier depletion stage, the voltage across the diode remains at the on-state voltage during the t1-t2 period. Combined with the charge state of the PN junction, the current model flowing through the diode is:

[0093]

[0094]

[0095] q E =(τ+T M )i

[0096] Where i is the current flowing through the diode, q E is the charge of the PN junction, q M is the charge stored at the PN junction boundary, T M is the transfer time, and τ is the carrier lifetime. E Determined by the PN junction material, it can be expressed as:

[0097]

[0098] Where v is the diode junction voltage, I s is the diode reverse saturation current, V Tj is the voltage equivalent of temperature.

[0099] In this stage, since the diode is actually still in the on state, the current flowing through the diode is also affected by the current of the uncontrolled rectifier valve, so the current flowing through the diode is:

[0100] i=i F +at

[0101] Wherein, a is the current change rate, a=di / dt.

[0102] In the minority carrier depletion stage, q M During the current decay process, changes occur and q is gradually depleted E . In this stage, q M Can be parsed as:

[0103]

[0104] In the minority carrier depletion time range, the current changes with slope a, and the process time is

[0105]

[0106] S42, diode reverse recovery stage.

[0107] When in the reverse recovery process, the current can be expressed as:

[0108]

[0109] The reverse recovery time constant is τ rr , and the carrier lifetime τ and carrier transfer time T M Related, it can be expressed as:

[0110]

[0111] Since when t=I RM / a+t F = t4-t1, the reverse recovery current is:

[0112] I RM / 10

[0113] Then t F Can be parsed as:

[0114] t F =τ rr log(10)+i RM / a

[0115] t S Charge in time:

[0116]

[0117] t F The amount of charge in time is:

[0118] Q F =τ rr i RM

[0119] Q rr =Q S +Q F

[0120] Then the reverse recovery time under the reverse recovery charge constraint is:

[0121]

[0122] Then, this process can be equivalent to the time-varying nonlinear resistance Crr, such as Figure 3 shown.

[0123] S5. Construct an electrical model of a high-voltage uncontrolled rectifier valve series diode assembly through electrical connection.

[0124] The electrical model of the high-voltage uncontrolled rectifier valve in series with the diode assembly adopts electrical connection to connect the diode reverse process models in the same time scale in series, that is, the low-frequency working equivalent model of the diode reverse process in series, such as Figure 4 As shown; or the physical process model of the reverse shutdown of the diode under lightning strike is connected in series, as shown Figure 5 As shown, the electrical model of the high-voltage uncontrolled rectifier valve series diode component is constructed.

[0125] S5. Establish an electrical model of series diodes for the entire lightning strike process.

[0126] The reverse process electrical model of the high-voltage uncontrolled rectifier valve in series with the diode for the entire lightning impulse process is used to extract the time scale characteristics of the lightning wave, that is, the lightning current rises rapidly before the steep wave and drops relatively slowly to the normal current state after the steep wave, such as Figure 6 As shown, the reverse process model of the switching diode is used to form the electrical model of the series diode of the entire lightning impulse process. When the high-voltage uncontrolled rectifier valve is in steady-state operation, the diode RC parallel model is used, and the voltage distribution characteristics of the series diode are as follows Figure 7 When the high-voltage uncontrolled rectifier valve is in a lightning transient state, the diode RC parallel model is switched to the diode nonlinear capacitance model according to the current change rate. The voltage distribution characteristics of the series diode are as follows: Figure 8 shown.

[0127] In summary, the method of this embodiment has the following beneficial effects compared with the prior art:

[0128] (1) This embodiment constructs a diode reverse turn-off physical model based on the physical process of power diodes on the time scale of lightning waves, thereby overcoming the defect that the time scale of the diode junction capacitance equivalent model is much larger than the time scale of lightning waves.

[0129] (2) The diode reverse turn-off physical model is conducive to analyzing the nonlinear distribution characteristics of the transient process of the lightning overvoltage of the series diode of the high-voltage uncontrolled rectifier valve, which helps to improve the lightning protection design of the high-voltage uncontrolled rectifier valve. The method of this embodiment can be used to analyze the voltage distribution characteristics of the high-voltage uncontrolled rectifier valve when the power system state suddenly changes, which is of great significance to the safe and stable operation of the high-voltage uncontrolled rectifier valve.

[0130] This embodiment also provides a modeling system for a transient process of a lightning strike of a diode assembly, including:

[0131] An architecture building module, used to build an electrical model architecture of the lightning strike time scale of a high-voltage uncontrolled rectifier valve series diode component according to the lightning wave time scale characteristics and the overall structural characteristics of the high-voltage uncontrolled rectifier valve;

[0132] A model division module is used to divide the reverse process electrical model of the diode into a reverse process power frequency working electrical model of the diode and a reverse process transient working electrical model of the diode according to the electrical model architecture;

[0133] The power frequency model module is used to construct a power frequency equivalent model of the diode reverse process based on the power frequency steady-state working time scale;

[0134] The lightning model module is used to build a physical process model of diode reverse shutdown under lightning strike based on the lightning wave time scale;

[0135] A series model module is used to construct an electrical model of a high-voltage uncontrolled rectifier valve series diode component through electrical connections;

[0136] The lightning transient module is used to build an electrical model of a series diode for the entire lightning impulse process based on the waveform characteristics of the lightning wave.

[0137] A modeling system for a diode component lightning transient process in this embodiment can execute a modeling method for a diode component lightning transient process provided by a method embodiment of the present invention, can execute any combination of implementation steps of the method embodiment, and has the corresponding functions and beneficial effects of the method.

[0138] This embodiment also provides a modeling device for a transient process of a lightning strike of a diode assembly, comprising:

[0139] at least one processor;

[0140] at least one memory for storing at least one program;

[0141] When the at least one program is executed by the at least one processor, the at least one processor implements the following Figure 1 The method shown.

[0142] A modeling system for a diode component lightning transient process in this embodiment can execute a modeling method for a diode component lightning transient process provided by a method embodiment of the present invention, can execute any combination of implementation steps of the method embodiment, and has the corresponding functions and beneficial effects of the method.

[0143] The present application also discloses a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. A processor of a computer device can read the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes Figure 1 The method shown.

[0144] This embodiment also provides a storage medium storing instructions or programs that can execute a method for modeling a transient process of a lightning strike on a diode component provided by an embodiment of the method of the present invention. When the instructions or programs are run, any combination of implementation steps of the method embodiment can be executed, and the corresponding functions and beneficial effects of the method can be obtained.

[0145] In some selectable embodiments, the function / operation mentioned in the block diagram may not occur in the order mentioned in the operation diagram. For example, depending on the function / operation involved, the two boxes shown in succession can actually be executed substantially simultaneously or the boxes can sometimes be executed in reverse order. In addition, the embodiment presented and described in the flow chart of the present invention is provided by way of example, for the purpose of providing a more comprehensive understanding of technology. The disclosed method is not limited to the operation and logic flow presented herein. Selectable embodiments are expected, wherein the order of various operations is changed and the sub-operation of a part for which is described as a larger operation is performed independently.

[0146] In addition, although the present invention is described in the context of functional modules, it should be understood that, unless otherwise specified, one or more of the functions and / or features described may be integrated into a single physical device and / or software module, or one or more functions and / or features may be implemented in separate physical devices or software modules. It is also understood that a detailed discussion of the actual implementation of each module is unnecessary for understanding the present invention. More specifically, in view of the properties, functions, and internal relationships of the various functional modules in the device disclosed herein, the actual implementation of the module will be understood within the conventional skills of the engineer. Therefore, those skilled in the art can implement the present invention set forth in the claims without excessive experimentation using ordinary techniques. It is also understood that the specific concepts disclosed are merely illustrative and are not intended to limit the scope of the present invention, which is determined by the full scope of the appended claims and their equivalents.

[0147] 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.

[0148] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0149] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0150] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0151] In the above description of this specification, the description with reference to the terms "one embodiment / example", "another embodiment / example" or "certain embodiments / examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0152] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

[0153] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the above embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A modeling method for a transient process of a lightning strike on a diode component, characterized in that: The following steps are involved: According to the characteristics of lightning wave time scale and the overall structural features of high-voltage uncontrolled rectifier valve, the electrical model framework of lightning strike time scale of high-voltage uncontrolled rectifier valve series diode assembly is constructed; According to the electrical model framework, the reverse process electrical model of the diode is divided into the reverse process power frequency working electrical model of the diode and the reverse process transient working electrical model of the diode; Based on the power frequency steady-state working time scale, an equivalent model of the diode reverse process power frequency working is constructed; Based on the lightning wave time scale, a physical process model of diode reverse shutdown under lightning strike is constructed; Through electrical connection, an electrical model of a high-voltage uncontrolled rectifier valve in series with a diode assembly is constructed; Based on the waveform characteristics of lightning waves, an electrical model of series diodes for the entire lightning impulse process is constructed; The construction of the physical process model of diode reverse shutdown under lightning strike includes: In the minority carrier depletion stage, the voltage across the diode is maintained at the on-state voltage. Combined with the charge state of the PN junction, the current model flowing through the diode is: q E =(τ+T M )i Where i is the current flowing through the diode, q E is the charge of the PN junction, q M is the charge stored at the PN junction boundary, T M is the transfer time, τ is the carrier lifetime; q E Determined by the PN junction material, expressed as: Where v is the diode junction voltage, I s is the diode reverse saturation current, V Tj is the voltage equivalent of temperature; In the minority carrier depletion stage, since the diode is in the on state, the current flowing through the diode is also affected by the current of the uncontrolled rectifier valve, so the current flowing through the diode is: i=i F +at Where a is the current change rate, a = di / dt; In the minority carrier depletion stage, q M During the current decay process, changes occur and q is gradually depleted E ; In the minority carrier depletion stage, q M Parses as: Within the minority carrier depletion time range, the current changes with slope a, and the process time is: When in the reverse recovery process, the current is expressed as: Among them, t3 represents the start time of the reverse recovery phase; the reverse recovery time constant is τ rr , and the carrier lifetime τ and carrier transfer time T M Related, expressed as: Since when t=I RM / a+t F When the reverse recovery current is: I RM / 10 Then t F Parses as: t F =τ rr log(10)+i RM / a t S Charge in time: t F The amount of charge in time is: Q F =t rr I RM Q rr =Q S +Q F Then the reverse recovery time under the reverse recovery charge constraint is: Among them, I RM Indicates the amplitude of the maximum reverse current; i RM Indicates the instantaneous value of the maximum reverse current.

2. A modeling method for a transient process of a lightning strike of a diode assembly according to claim 1, characterized in that: The waveform of the lightning wave is that the lightning current rises rapidly before the steep wave and drops relatively slowly to a normal current state after the steep wave.

3. A modeling method for a transient process of a lightning strike of a diode assembly according to claim 1, characterized in that: The power frequency operation equivalent model of the diode reverse process is constructed in a simplified form in which the junction capacitance C is connected in parallel with the diode internal resistance R.

4. A modeling method for a transient process of a lightning strike of a diode assembly according to claim 1, characterized in that: The electrical model of the high-voltage uncontrolled rectifier valve series diode assembly is constructed through electrical connection, including: By adopting electrical connection, the diode reverse process models under the same time scale are connected in series to form an electrical model of a high-voltage uncontrolled rectifier valve in series with a diode assembly.

5. A modeling method for a transient process of a lightning strike of a diode assembly according to claim 4, characterized in that: The diode reverse process models under the same time scale are connected in series, including: Connect the equivalent model of the diode reverse process working at power frequency in series; or, The physical process model of diode reverse shutdown under lightning strike is connected in series.

6. A modeling method for a transient process of a lightning strike of a diode assembly according to claim 1, characterized in that: The electrical model of the series diode for the whole process of lightning impulse is constructed based on the waveform characteristics of the lightning wave, including: The time scale characteristics of lightning waves are extracted, and the reverse process model of the switching diode is formed to form an electrical model of the series diode for the entire process of lightning impulse.

7. A modeling system for a transient process of a lightning strike of a diode component, applied to a modeling method for a transient process of a lightning strike of a diode component as claimed in any one of claims 1 to 6, characterized in that: include: An architecture building module, used to build an electrical model architecture of the lightning strike time scale of a high-voltage uncontrolled rectifier valve series diode component according to the lightning wave time scale characteristics and the overall structural characteristics of the high-voltage uncontrolled rectifier valve; A model division module is used to divide the reverse process electrical model of the diode into a reverse process power frequency working electrical model of the diode and a reverse process transient working electrical model of the diode according to the electrical model architecture; The power frequency model module is used to construct a power frequency equivalent model of the diode reverse process based on the power frequency steady-state working time scale; The lightning model module is used to build a physical process model of diode reverse shutdown under lightning strike based on the lightning wave time scale; A series model module is used to construct an electrical model of a high-voltage uncontrolled rectifier valve series diode component through electrical connections; The lightning transient module is used to build an electrical model of a series diode for the entire lightning impulse process based on the waveform characteristics of the lightning wave.

8. A modeling device for a transient process of a lightning strike on a diode assembly, characterized in that: include: at least one processor; at least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor implements the method according to any one of claims 1 to 6.

9. A computer-readable storage medium storing a program executable by a processor, characterized in that: The processor-executable program is used to perform the method according to any one of claims 1 to 6 when executed by the processor.

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