Cold cathode trigger tube model and improved cold cathode trigger tube model capable of controlling conduction delay time

Abstract

The invention discloses a cold cathode trigger tube model and an improved structure capable of controlling conduction delay time thereof, and relates to the technical field of integrated circuit design, and the cold cathode trigger tube model comprises a main gap channel circuit, a trigger gap channel circuit and a control module. According to the cold cathode trigger tube SPICE improved model capable of controlling the conduction delay time, a gas discharge switch model circuit is added to a trigger gap channel circuit of a cold cathode trigger tube SPICE model, and the gas discharge switch model circuit is used as a switching device for controlling the conduction delay time. A cold cathode trigger tube SPICE model with universality and high realizability is designed and researched, different parameters of the model can be modified to meet requirements of different scenes, a foundation is laid for follow-up research work, a gas discharge switch model circuit is added into a trigger gap channel circuit, and the simulation performance of the gas discharge switch model circuit is improved. The problem that the conduction delay time of a traditional cold cathode trigger tube is uncontrollable is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuit design, and in particular to a cold cathode trigger tube model and an improved version thereof capable of controlling a conduction delay time. Background Art

[0002] As a type of triggered spark gap switch, the cold cathode trigger tube has some characteristics that cannot be replaced by other types of devices. It has a wide range of applications, mainly as a high-voltage pulse switch for various high-voltage pulse generators, aircraft engine ignition, and protection of high-voltage equipment and components. However, there is currently no complete, simple and reliable SPICE model.

[0003] This paper proposes a cold cathode trigger tube SPICE model to meet the functions of modern cold cathode trigger tubes, and has carried out simulation verification. The model can modify different parameters to meet the needs of different scenarios.

[0004] In response to some problems found in the simulation verification process, an improved cold cathode trigger tube model was proposed based on the gas discharge principle. This improved model effectively solves the problem of uncontrollable conduction delay time of traditional cold cathode trigger tubes. At the same time, application simulation verification was carried out in three mainstream circuit simulation software: LTspice, Multisim and Pspice. The simulation results further verified the universality of the model established in this paper, which has strong feasibility, and laid a foundation for subsequent research work. Summary of the invention

[0005] The present invention aims to provide a cold cathode trigger tube model and an improved version thereof with controllable conduction delay time, so as to solve the problem that there is no complete, simple and reliable SPICE model and the problem that the conduction delay time of the traditional cold cathode trigger tube is uncontrollable.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A cold cathode trigger tube model comprises a main gap channel circuit, a trigger gap channel circuit and a control module, wherein the main gap channel circuit comprises a first circuit simulating a non-working state and a second circuit simulating a working state, wherein in the non-working state, the main gap channel circuit has a relatively large insulation resistance, which is greater than 10MΩ, and in the working state, the main gap channel resistance drops to a few tenths of an ohm, which is approximately a short-circuit state; the trigger gap channel circuit simulates a process in which, when the voltage applied across the main gap channel is lower than the self-breakdown voltage of the trigger tube, a trigger pulse with a certain amplitude and width is applied to the trigger electrode, and the trigger gap between the trigger electrode and the adjacent electrode breaks down and conducts to generate discharge; the control module simulates the self-breakdown voltage of the cold cathode trigger tube and the working voltage of the cold cathode trigger tube, and limits the working current range of the cold cathode trigger tube.

[0008] A further technical feature is that the main gap channel circuit includes, from left to right, a first circuit and a second circuit from node A to node K, and an external working voltage acts between the node A and the node K;

[0009] The first circuit includes a resistor R_Off and an inductor L_Off connected in series, and also includes a capacitor C_Off connected in parallel with the resistor R_Off and the inductor L_Off;

[0010] The second circuit includes a resistor R_On, an inductor L_On, a voltage-controlled switch S_Open, a shunt switch D1 from left to right, and a behavior voltage source B_E_On connected in series, and also includes a capacitor C_On connected in parallel with the resistor R_On and the inductor L_On, a shunt switch D2 and a behavior voltage source B_E_FwBreak connected in series from left to right, and a shunt switch diode D1 and a behavior voltage source B_E_On connected in parallel, a behavior voltage source B_E_ReBreak connected in series, and a shunt switch D3 from right to left, and a shunt switch diode D1 and a behavior voltage source B_E_On connected in parallel,

[0011] The voltage-controlled switch S_Open is turned on or off by the node Open, a node FwBreak is set between the shunt switch D2 and the behavior voltage source B_E_FwBreak, and a node ReBreak is set between the behavior voltage source B_E_ReBreak and the shunt switch D3;

[0012] The trigger gap channel circuit includes, from left to right, a flow control switch W1, a resistor R_Tk and an inductor L_Tk connected in series from node T to node K, and also includes a capacitor C_Tk connected in parallel with the resistor R_Tk and the inductor L_Tk;

[0013] The control module includes a self-breakdown voltage control module, an operating voltage control module and an operating current limiting module;

[0014] The self-breakdown voltage control module includes a DC voltage source V_P with one end grounded and the other end set at a node V_P, a DC voltage source V_D with one end grounded and the other end set at a node V_D, and a DC voltage source V_A with one end grounded and the other end set at a node V_A, and the DC voltage source V_P, the DC voltage source V_D and the DC voltage source V_A are respectively connected in parallel with a resistor V_P, a resistor V_D and a resistor V_A at both ends of each of the DC voltage source V_P, the DC voltage source V_D and the DC voltage source V_A;

[0015] The working voltage control module includes a behavior voltage source B_Ctrl with one end grounded and the other end connected to the Ctrl node, a resistor R_Ctrl is connected in parallel at both ends of the behavior voltage source B_Ctrl, a behavior voltage source B_Tril, a current source G_Omin in the form of TBL and a resistor R_Omin are connected in series with each other at both ends to form a loop, and also includes a behavior voltage source B_Tmin with one end grounded and the other end connected to the Tmin node, and a resistor R_Tmin is connected in parallel at both ends of the behavior voltage source B_Tmin;

[0016] The working current limiting module comprises a behavior voltage source B_Open with one end grounded and the other end connected to an Open node, and resistors R_Open are connected in parallel at both ends of the behavior voltage source B_Open.

[0017] An improved model of a cold cathode trigger tube capable of controlling a conduction delay time also includes a gas discharge switch model circuit, which is added to the trigger gap channel circuit and used as a switch device to control the conduction delay time.

[0018] A further technical feature is that the gas discharge switch circuit has a behavioral current source B_Ind, a voltage-controlled switch S_Ch and a behavioral voltage source B_Res connected in series from node T1 to node T2, and also includes a capacitor C_Cap connected in parallel with the behavioral current source B_Ind, the voltage-controlled switch S_Ch and the behavioral voltage source B_Res.

[0019] A further technical feature is that the breakdown of the gas discharge switch is equivalent to the conduction of the voltage-controlled switch S_Ch, and the voltage-controlled switch S_Ch is controlled to be turned on or off by the gap switch control circuit connected to the node Ch_On.

[0020] A further technical feature is that in the gap switch control circuit, the voltage-controlled switch S_Ch is turned on or off by the voltage source B_Ch_On, the voltage source B_Ch_On is connected to the node Ch_On, and its output is determined by the OR logic composed of the node voltage V(Delay_Ovre) and the node voltage V(Maintain), if any one of V(Delay_Ovre) and V(Maintain) is greater than 0.5, then the output of B_Ch_On is 1, the switch S_Ch is turned on, the voltage source B_Ch_On is also connected in series with the voltage source B_Ch_On, and also includes a capacitor C1 connected in parallel with the voltage source B_Ch_On and the voltage source B_Ch_On;

[0021] The node voltage V(Delay_Ovre) is controlled by the behavior voltage source B_Dly_Ovr to output a value, and its output is true if the node voltage V(T_Over) is greater than the node voltage V(Delay), and the output is 1. The node voltage V(T_Over) indicates the time when the gap voltage exceeds the static breakdown voltage, and the node voltage V(Delay) indicates the breakdown delay time;

[0022] The V(T_Over) is generated by the behavior voltage source B_T_Ovr, and its output is the simulation time Time minus the voltage value V(T_B) of the node T_B, in seconds. The circuit of the simulation time is composed of the behavior voltage source B_Time, the switch S1 and the capacitor C2 connected in series to form a loop. The node Time is inserted between the behavior voltage source B_Time and the switch S1. The node output is controlled by the behavior voltage source B_Time to output the simulation time Time. The node T_B is inserted between the switch S1 and the capacitor C2. The switch S1 is turned on by the behavior voltage source B_! Ovr. Its output is that when V(Over) is greater than 0.5V, the behavior voltage source B_! Ovr drops from 1V to 0V, the switch S1 is disconnected, the capacitor C2 is frozen, and then the voltage of the node T_B is frozen;

[0023] The voltage value V(Over) of the node Over is provided by the voltage source B_Ovr, whose output is an If judgment statement. If the gap voltage is greater than the static breakdown voltage, the output is 1 when true, otherwise it is 0. When the judgment is true, the tanh function is used to smooth the transition of the switch S1 from the off state to the on state;

[0024] The size of the gap voltage is controlled by the voltage V(V_Gap) at the node V_Gap, which is generated by the behavioral voltage B_V_Gap, and its output is the absolute value of the voltage difference between T1 and T2. The size of the static breakdown voltage is controlled by the voltage V(V_Break) at the node V_Break, which is generated by the behavioral voltage B_V_Break, and its output is an empirical formula:

[0025]

[0026] The unit is kV;

[0027] V(Delay) is generated by the behavioral voltage source B_Dly, and its output is the empirical formula:

[0028]

[0029] Where: E is the gap electric field, in KV / cm, calculated by the node E_Gap, generated by the behavioral voltage source B_E_Gap, whose output is the ratio of the node voltage V(V_Gap) to the channel gap D, ρ is the gap gas volume density, in g / cm 3 , calculated at node Rho_V, generated by the behavioral voltage source B_Rho, whose output is P / 760×1.2, where P is the gap gas pressure.

[0030] The node voltage V(Maintain) is controlled by the behavioral voltage source B_Maint. When the channel current is greater than the minimum current value, the output of V(Maintain) is 1. The minimum current value is represented by the voltage V(I_Min) at the node I_Min, which is generated by the DC voltage source B_I_Min. The channel current is represented by the voltage V(I_Ch) at the node I_Ch, which is generated by the behavioral current source B_I_Ch. The output is the absolute value of the channel current.

[0031] A further technical feature is that the output value of the behavioral voltage source B_Res is the product of the current passing through itself and the voltage at the node R_Ch, which represents the channel gap resistance after the gas discharge switch is broken down. The output value of the behavioral voltage source B_Res is based on a formula for calculating the channel resistance:

[0032]

[0033] Where c is the proportional constant 876, d is the gap distance, i is the channel current, and r is the channel radius in meters;

[0034] The channel radius formula is:

[0035]

[0036] Wherein i is the channel current, in kV, t is the channel formation time, in μs, ρ is the gap gas density, in g / cm3, the channel radius formula drives the voltage at the node Ch_Rad through the current source B_Ch_Rad, and the circuit is connected in series from the ground node to the node Ch_Rad with the current source B_Ch_Rad and the diode D4 from left to right, and the current source B_Ch_Rad and the diode D4 are also connected in parallel with the capacitor C5 and the resistor R3;

[0037] The discharge switch model circuit also includes a timing circuit for calculating the time of the last transition of the switch S_Ch from off to on,

[0038] The timing circuit is composed of a capacitor C6 and a switch S2 connected in series, a node Time is inserted before the switch S2, a node T_C is inserted between the switch S2 and the capacitor C2, the switch S2 is controlled to be turned on by the behavior voltage source B_! On, and its output is that when V(Ch_On) is greater than 0.5V, the behavior voltage source B_! On drops from 1V to 0V, the switch S2 is disconnected, the capacitor C6 is frozen, and then the voltage of the node T_C is frozen, and the output time is represented by the voltage at the node T_arc, the node T_arc is driven by the behavior voltage source B_T_Arc, and its output is the simulation time Time minus the voltage V(T_C) at the node T_C;

[0039] After the voltage across the inductor is converted into current by the behavioral current source B_Ind, the current is integrated by the capacitor C4. The integration circuit is a behavioral voltage source B_Ch_Rad connected in parallel with the capacitor C4. A node Int_V_L is inserted between the voltage source B_Ch_Rad and the capacitor C4. The integration result generates a voltage at the node Int_V_L. The current generated by the behavioral current source B_Ind is set to the voltage V(Int_V_L) generated at the node Int_V_L divided by the voltage V(L_Ch) at the node L_Ch. The voltage at the node L_Ch is generated by the behavioral voltage source B_L_Ch. The output of the voltage source B_L_Ch is the inductance expression:

[0040]

[0041] Wherein d is the gap distance, r is the channel radius, and the output of the voltage source B_L_Ch adopts the limiting function limit.

[0042] A further technical feature is that the gap switch control circuit also includes a static breakdown weakening module, and the static breakdown suppression module includes a node V_Break_End. The voltage at the node V_Break_End is generated by a behavioral voltage source B_Brk_End. The output of the behavioral voltage source B_Brk_End is a static breakdown voltage V(V_Break) multiplied by a weakening coefficient r. The output of the node Over becomes a method for determining whether the gap voltage V(V_Gap) is greater than the weakened static breakdown voltage V(V_Break_End).

[0043] A further technical feature is that the gas discharge switch model circuit and the static breakdown voltage weakening module are respectively inserted into the trigger gap channel circuit and the gas discharge switch model circuit, the gas discharge switch inserted with the static breakdown voltage weakening module is placed between the parallel voltage source V_E_M and the resistor R_MK, a node M is set between the voltage source V_E_M and the gas discharge switch, the trigger gap circuit is connected to a voltage source B_E_T, and the voltage source output is used to judge whether the current of the resistor R_MK is greater than the minimum current value V(I_Min), if so, the voltage V(M) at the node M is output, if not, 0 is output.

[0044] The principle and beneficial effects of this technical solution:

[0045] 1. This paper proposes and studies a cold cathode trigger tube SPICE model with universality and strong feasibility, in which all characteristic parameters conform to the detailed specifications of the RQ-10 cold cathode trigger tube, and the model can modify different parameters to meet the needs of different scenarios, laying a foundation for subsequent research work.

[0046] 2. The present invention also proposes a gas discharge switch model circuit, which is added to the trigger gap channel circuit of the present invention. Through simulation experiments, it is verified that the problem of uncontrollable conduction delay time of traditional cold cathode trigger tubes is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is the circuit diagram of the main gap channel;

[0048] Figure 2 This is the circuit diagram for triggering the gap channel;

[0049] Figure 3 It is a self-breakdown voltage control module;

[0050] Figure 4 The general characteristic curve (a) and the approximate processing line (b) of the cold cathode trigger tube;

[0051] Figure 5 It is the minimum trigger circuit module;

[0052] Figure 6 It is a working current limiting module;

[0053] Figure 7 It is a circuit diagram for self-breakdown circuit voltage test;

[0054] Figure 8 This is the simulation waveform diagram of the self-breakdown voltage test;

[0055] Fig. 9 This is the minimum trigger voltage test circuit diagram;

[0056] Fig.10 This is the simulation waveform diagram for the minimum trigger voltage test;

[0057] Fig.11 This is the simulation waveform diagram for the minimum working voltage test;

[0058] Fig.12 Test the simulation waveform for the highest working voltage;

[0059] Fig.13 Test the simulated waveform for the working current range;

[0060] Fig.14 A gas discharge switch circuit;

[0061] Fig.15 It is a gap switch control module;

[0062] Fig.16 It is the channel resistance calculation module;

[0063] Fig.17 Verify circuits for gas discharge switches;

[0064] Fig.18 Verify waveforms for gas discharge switches;

[0065] Fig.19 To weaken the module for static breakdown voltage;

[0066] Fig. 20 It is an improved cold cathode trigger tube model (trigger gap channel);

[0067] Fig.21 This is the simulation waveform diagram of the self-breakdown voltage test;

[0068] Fig. 22 This is the simulation waveform diagram for the minimum trigger voltage test;

[0069] Fig.23 This is the simulation waveform diagram for the minimum working voltage test;

[0070] Fig.24 This is the simulation waveform diagram for the highest working voltage test;

[0071] Fig.25 Simulation waveform diagram for working current range test;

[0072] Fig.26 Effect of different gap distances on the turn-on delay time of the improved cold cathode trigger tube model (LTspice);

[0073] Fig. 27 The effect of different gas pressures on the turn-on delay time of the improved cold cathode trigger tube model (LTspice);

[0074] Fig.28 The effect of different gap voltages on the turn-on delay time of the improved cold cathode trigger tube model (LTspice);

[0075] Fig.29 The effect of different gap distances on the turn-on delay time of the improved cold cathode trigger tube model (Multisim);

[0076] Fig.30 The effect of different gas pressures on the conduction delay time of the improved cold cathode trigger tube model (Multisim);

[0077] Fig.31 The effect of different gap voltages on the turn-on delay time of the improved cold cathode trigger tube model (Multisim);

[0078] Fig.32 The effect of different gap distances on the turn-on delay time of the improved cold cathode trigger tube model (Pspice);

[0079] Fig.33 The effect of different gas pressures on the turn-on delay time of the improved cold cathode trigger tube model (Pspice);

[0080] Fig.34 The effect of different gap voltages on the turn-on delay time of the improved cold cathode trigger tube model (Pspice); DETAILED DESCRIPTION

[0081] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments:

[0082] Example 1

[0083] 1 A cold cathode trigger tube model

[0084] The invention comprises a main gap channel circuit, a trigger gap channel circuit and a control module circuit. The main gap channel circuit comprises a first circuit for simulating a non-working state and a second circuit for simulating a working state. In the non-working state, the main gap channel circuit has a relatively large insulation resistance, which is greater than 10MΩ. In the working state, the resistance of the main gap channel drops to a few tenths of an ohm, which is close to a short-circuit state. The trigger gap channel circuit simulates a process in which a trigger gap between the trigger electrode and an adjacent electrode is broken down and turned on to generate discharge when a trigger pulse with a certain amplitude and width is applied to the trigger electrode when the voltage applied to both ends of the main gap channel is lower than the self-breakdown voltage of the trigger tube. The control module simulates the self-breakdown voltage of the cold cathode trigger tube and the working voltage of the cold cathode trigger tube, and limits the working current range of the cold cathode trigger tube.

[0085] 1.1 Main gap channel circuit

[0086] like Figure 1 As shown, it includes, from left to right, a first circuit and a second circuit from node A to node K, and an external working voltage acts between node A and node K;

[0087] The first circuit includes a resistor R_Off and an inductor L_Off connected in series, and also includes a capacitor C_Off connected in parallel with the resistor R_Off and the inductor L_Off;

[0088] The second circuit includes a resistor R_On, an inductor L_On, a voltage-controlled switch S_Open, a shunt switch D1 from left to right, and a behavior voltage source B_E_On connected in series, and also includes a capacitor C_On connected in parallel with the resistor R_On and the inductor L_On, a shunt switch D2 and a behavior voltage source B_E_FwBreak connected in series from left to right, and the shunt switch diode D1 and the behavior voltage source B_E_On are connected in parallel with each other, and a behavior voltage source B_E_ReBreak and a shunt switch D3 from right to left are connected in series with the shunt switch diode D1 and the behavior voltage source B_E_On are connected in parallel with each other,

[0089] The voltage-controlled switch S_Open is turned on or off by the node Open, a node FwBreak is set between the shunt switch D2 and the behavior voltage source B_E_FwBreak, and a node ReBreak is set between the behavior voltage source B_E_ReBreak and the shunt switch D3.

[0090] Under certain triggering conditions, when an external working voltage is applied to both ends of the main gap channel, the cold cathode trigger tube as a whole may be in working or non-working state, depending on the magnitude and direction of the external voltage. When the cold cathode trigger tube is in non-working state, the main gap channel will show a large insulation resistance. Generally, the resistance of the main gap channel of a 10M trigger tube is reduced to a few tenths of an ohm, which is close to a short circuit state. Figure 1 In the figure, R_On and R_Off are used above Ω, and after conduction, they represent the channel resistance of the main gap channel in the working state and the non-working state respectively. C_On and L_On represent the distributed capacitance and distributed inductance of the main gap channel in the on state respectively, and C_Off and L_Off represent the distributed capacitance and distributed inductance of the main gap channel in the non-conducting state respectively; the output voltages of the behavioral voltage sources B_E_FwBreak and B_E_ReBreak represent the forward and reverse breakdown threshold voltages respectively, and the output voltage of the behavioral voltage source B_E_On represents the working voltage of the main gap channel. D1, D2 and D3 serve as branch switches of the three branches; the voltage-controlled switch S_Open is used to limit the working current of the main gap channel.

[0091] 1.2 Trigger gap channel circuit

[0092] like Figure 2 As shown, the trigger gap channel circuit includes, from left to right, a flow control switch W1, a resistor R_Tk and an inductor L_Tk connected in series from node T to node K, and also includes a capacitor C_Tk connected in parallel with the resistor R_Tk and the inductor L_Tk;

[0093] Under normal circumstances, when the voltage applied to both ends of the main gap channel is lower than the self-breakdown voltage of the trigger tube, the trigger tube will not break down and conduct. At this time, if a trigger pulse with a certain amplitude and width is applied to the trigger electrode, the trigger gap between the trigger electrode and the adjacent electrode will break down and conduct, generating discharge. The discharge process is also the breakdown and conduction of the trigger tube. Due to the possible interference of external uncertain factors, in order to avoid the trigger tube from being mis-conducted, it is necessary to set the minimum trigger current I TKmin . Figure 2 In the example, W1 acts as a flow control switch. When the current in the trigger gap channel is greater than I TKmin When the switch is closed, the trigger pulse can reach the adjacent electrode. R_Tk, C_Tk and L_Tk represent the distributed resistance, distributed inductance and distributed capacitance of the trigger gap channel circuit respectively.

[0094] 1.3 Control module circuit

[0095] It includes a self-breakdown voltage control module, an operating voltage control module and an operating current limiting module;

[0096] 1.3.1 Self-breakdown voltage control module

[0097] The self-breakdown voltage of the cold cathode trigger tube is mainly affected by many factors such as the type and pressure of the gas in the tube, the gap distance between adjacent electrodes, the electrode material, size, shape and electrode surface condition. The following is a formula for calculating the self-breakdown voltage of the cold cathode trigger tube based on three parameters: the ionization constant, the gap distance between adjacent electrodes and the gas pressure in the trigger tube:

[0098]

[0099] Where: a is the gas constant; d is the gap distance between adjacent electrodes in the trigger tube; p is the gas pressure in the trigger tube.

[0100] The output voltages of three different DC voltage sources are used to replace the above three parameters to realize the input of parameters and the calculation of self-breakdown voltage.

[0101] like Figure 3 As shown, the self-breakdown voltage control module includes a DC voltage source V_P with one end grounded and the other end set at a node V_P, a DC voltage source V_D with one end grounded and the other end set at a node V_D, and a DC voltage source V_A with one end grounded and the other end set at a node V_A, and the DC voltage source V_P, the DC voltage source V_D and the DC voltage source V_A are each connected in parallel with a resistor V_P, a resistor V_D and a resistor V_A at both ends, respectively, wherein R_A, R_D and R_P represent the series internal resistances of the three DC voltage sources, respectively.

[0102] 1.3.2 Working voltage control module

[0103] A trigger pulse with a certain amplitude and width is applied, and the required working voltage is calculated from the general working characteristic curve of the cold cathode trigger tube. However, the general working characteristic curve of the actual cold cathode trigger tube is difficult to express in the form of a mathematical function, such as Figure 4 (a) is shown. Here, the TBL current source in LTspice is used to simulate the characteristic curve. According to the requirements of the TBL current source, it is impossible to use the same input to obtain different outputs. Here, the general characteristic curve of the cold cathode trigger tube is approximated, that is, as many key node data as possible are taken to clamp several points of the curve

[22] , and the following is obtained: Figure 4 (b) The relationship line shown.

[0104] like Figure 5 As shown, the working voltage control module includes a behavior voltage source B_Ctrl with one end grounded and the other end connected to the Ctrl node, and a resistor R_Ctrl is connected in parallel at both ends of the behavior voltage source B_Ctrl, and also includes a behavior voltage source B_Tril, a current source G_Omin in the form of TBL and a resistor R_Omin connected in series at both ends to form a loop, and also includes a behavior voltage source B_Tmin with one end grounded and the other end connected to the Tmin node, and a resistor R_Tmin is connected in parallel at both ends of the behavior voltage source B_Tmin;

[0105] The behavior voltage source B_Tril provides the absolute value of the external trigger voltage for the TBL-type current source G_Omin, so that the output of G_Omin corresponds to the working voltage U in the cold cathode trigger tube approximate processing line. AK For currents of the same value, the resistance R_Omin is the equivalent series resistance of B_Tril and G_Omin (b) Figure 5 Approximate processing line. The voltage value of node Tmin is generated by the behavior voltage source B_Tmin, which represents the set minimum trigger voltage U Tmin The voltage of node Ctrl is generated by the behavioral voltage source B_Ctrl, and its output uses the IF judgment statement. When the trigger gap channel voltage is greater than the minimum trigger voltage U Tmin The output is 1 when the voltage is 0, otherwise it is used to affect the working voltage of the main gap channel.

[0106] 1.3.3 Working current limiting module

[0107] According to the general working characteristic curve of the cold cathode trigger tube, when a larger working voltage is applied, the main gap channel circuit may have a larger working current, while the general cold cathode trigger tube has a limited working current range. When the main gap current is less than the maximum working current I opmax When , the voltage at the node Open closes the voltage-controlled switch S_Open, and the entire main gap channel is closed, so that the cold cathode trigger tube can work normally.

[0108] like Figure 6 As shown, the working current limiting module includes a behavior voltage source B_Open with one end grounded and the other end connected to the Open node, and a resistor R_Open is connected in parallel at both ends of the behavior voltage source B_Open. The output of the behavior voltage source is an If judgment statement, which judges when the main gap current I(R_On) is less than the given maximum working current I opmax =10K, the result is true and output 1, otherwise output 0.

[0109] 1.4 Characteristic parameter verification and problem analysis of a cold cathode trigger tube

[0110] Referring to the cold cathode trigger tube test method of the electronic industry standard of the People's Republic of China, the constructed cold cathode trigger tube SPICE model was tested and verified under the circuit simulation software LTspice. Considering the actual situation of the circuit simulation software, the verification circuit was simplified during the simulation. In the test, the resistance values ​​of resistors R1 and R2 were 0.001Ω and 20Ω respectively, the capacitance value of capacitor C1 was 0.94μF, and the types of diodes D1, D2 and D3 were all set to 1N5817.

[0111] 1.4.1 Self-breakdown voltage test

[0112] according to Figure 7 As shown in the figure, the cold cathode trigger tube of the present invention is connected, and the DC voltage applied to both ends of the main gap is slowly increased within the specified voltage rise time until the main gap breaks down, and the breakdown voltage value is recorded, which is the self-breakdown voltage value of the trigger tube.

[0113] The output voltage of the behavioral voltage source B_Open is set to 1V, so that the voltage-controlled switch S_Open is continuously closed. The voltage source V3 generates a pulse voltage with an initial value of 0, a peak value of 30kV, a delay time of 0s, a rise time of 50ns, a duration of 0s, and a fall time of 50ns. CTT is the established cold cathode trigger tube equivalent model. The measurement of the main gap channel current is equivalent to measuring the current flowing through the resistor R_On. The simulation waveform is as follows: Figure 8 shown.

[0114] 1.4.2 Minimum trigger voltage test

[0115] according to Fig. 9 Connect the tube to be tested. Apply the specified working voltage to both ends of the main gap, gradually increase the trigger voltage to make the trigger tube work, and record the voltage value of the DC voltage of the trigger tube at this time, which is the minimum trigger voltage of the trigger tube.

[0116] The voltage source V3 generates a constant DC voltage with an amplitude of 9 kV, and the voltage source V4 generates a pulse voltage with an initial value of 0, a peak value of 30 kV, a delay time of 0 s, a rise time of 50 ns, a duration of 0 s, and a fall time of 50 ns. The simulation waveform is as follows: Fig.10 shown.

[0117] 1.4.3 Working voltage range test

[0118] according to Fig. 9 Connect the tube to be tested. Under the specified triggering conditions, gradually increase the DC voltage applied to both ends of the main gap to make the trigger tube work, and record the DC voltage value, which is the minimum working voltage of the trigger tube. The voltage source V3 generates a pulse voltage with an initial value of 0, a peak value of 10kV, a delay time of 0s, a rise time of 50ns, a duration of 0s, and a fall time of 50ns. The voltage source V4 generates a constant DC voltage with an amplitude of 20kV. The simulation waveform is as follows: Fig.11 shown.

[0119] like Fig.12 As shown in the figure, the minimum trigger voltage test result shows that the minimum trigger voltage of the trigger tube is U Tmin =3.00kV, if the DC voltage source V4 output is changed to make its output slightly larger than the voltage U Tmin , the output peak value of the voltage source V3 changes to 15kV, record the moment when the trigger tube starts working, and record the DC voltage value, which is the maximum working voltage of the trigger tube.

[0120] 1.4.4 Working current range test

[0121] according to Fig. 9 Connect the tube under test, apply the specified trigger voltage and working voltage, make the trigger tube work normally, and measure the maximum working current value. Voltage source V3 generates a pulse voltage with an initial value of 0, a peak value of 15kV, a delay time of 0s, a rise time of 50ns, a duration of 150ns, and a fall time of 10ns. Voltage source V4 generates a pulse voltage with an initial value of 0, a peak value of 20kV, a delay time of 0s, a rise time of 50ns, a duration of 0s, and a fall time of 50ns. The simulation waveform is as follows: Fig.13 shown.

[0122] Through the above test results and in comparison with the RQ-10 cold cathode trigger tube test standard, as shown in Table 1, various characteristic parameters of the cold cathode trigger tube SPICE model designed by the present invention meet the standard requirements.

[0123] Table 1 Test results and standard comparison

[0124]

[0125]

[0126] During the test, it was found that the turn-on delay time of the cold cathode trigger tube depends on the arrival time of the external main gap channel voltage and the trigger voltage. In the absence of a control device, the turn-on delay time is difficult to control artificially.

[0127] Example 2

[0128] 2 An Improved Model of Cold Cathode Trigger Tube

[0129] In response to the problem raised in the first embodiment, the present invention proposes a gas discharge switch added to the cold cathode trigger tube SPICE model in the first embodiment to control the turn-on delay time.

[0130] 2.1 Gas discharge switch circuit

[0131] like Fig.14 As shown, the gas discharge switch circuit is composed of four basic elements. The gas discharge switch circuit has a behavioral current source B_Ind, a voltage-controlled switch S_Ch and a behavioral voltage source B_Res connected in series from node T1 to node T2, and also includes a capacitor C_Cap connected in parallel with the behavioral current source B_Ind, the voltage-controlled switch S_Ch and the behavioral voltage source B_Res.

[0132] Among them, T1 and T2 serve as the input and output terminals of the external power supply, the behavioral current source B_Ind is used to represent the distributed inductance of the channel, the voltage-controlled switch S_Ch controls the on and off of the channel, and the behavioral voltage source B_Res is used to represent the distributed resistance of the channel.

[0133] 2.1.1 Gap switch control

[0134] like Figure 14-15 As shown, the breakdown of the gas discharge switch is equivalent to the closing of the voltage-controlled switch S_Ch. The closing of S_Ch is controlled by the voltage source B_Ch_On. The voltage source B_Ch_On is connected to the node Ch_On. Its output is determined by the OR logic composed of V(Delay_Over) and V(Maintain). If any one of V(Delay_Over) and V(Maintain) is greater than 0.5V, the output of B_Ch_On is 1V, and the switch S_Ch is turned on. The voltage source B_Ch_On is also connected in series with the voltage source B_Ch_On, and also includes a capacitor C1 connected in parallel with the voltage source B_Ch_On. The existence of the resistor R1 and the capacitor C1 provides a limited time for the rise of the node voltage V(Ch_On), thereby ensuring that the transition time of the switch S_Ch is limited.

[0135] 2.1.1.1 Breakdown Delay

[0136] like Fig.15 As shown, the node voltage V(Delay_Ovre) is controlled by the behavior voltage source B_Dly_Ovr to output a value, and its output is true if the judgment node voltage V(T_Over) is greater than the node voltage V(Delay), and the output is 1. The node voltage V(T_Over) indicates the time when the gap voltage exceeds the static breakdown voltage, and the node voltage V(Delay) indicates the breakdown delay time;

[0137] V(T_Over) is generated by the behavior voltage source B_T_Ovr, and its output is the simulation time Time minus the voltage value V(T_B) of the node T_B, in seconds. The circuit of the simulation time is composed of the behavior voltage source B_Time, switch S1 and capacitor C2 connected in series to form a loop. The node Time is inserted between the behavior voltage source B_Time and the switch S1. The node output is controlled by the behavior voltage source B_Time, and the simulation time Time is output. The node T_B is inserted between the switch S1 and the capacitor C2. The switch S1 is turned on by the behavior voltage source B_! Ovr. Its output is when V(Over) is greater than 0.5V, the behavior voltage source B_! Ovr drops from 1V to 0V, the switch S1 is disconnected, the capacitor C2 is frozen, and then the voltage of the node T_B is frozen;

[0138] The voltage value V(Over) of the node Over is determined by the voltage source B_Ovr, whose output is an If judgment statement. If the gap voltage is greater than the static breakdown voltage, the output is 1 when it is true, otherwise it is 0. Here, when the IF statement judgment condition is true, the result uses the tanh function to smooth the transition of the switch S1 from the off state to the on state to avoid discontinuities that may prevent the simulation solution from converging.

[0139] The size of the gap voltage is controlled by the voltage V(V_Gap) at the node V_Gap, which is generated by the behavioral voltage B_V_Gap. Its output is the absolute value of the voltage difference between T1 and T2. The size of the static breakdown voltage is controlled by the voltage V(V_Break) at the node V_Break, which is generated by the behavioral voltage B_V_Break. Its output is an empirical formula:

[0140]

[0141] The unit is kV; E

[0142] V(Delay) is generated by the behavioral voltage source B_Dly, and its output is the empirical formula:

[0143]

[0144] Where: E is the gap electric field, in KV / cm, calculated by the node E_Gap, generated by the behavioral voltage source B_E_Gap, whose output is the ratio of the node voltage V(V_Gap) to the channel gap D, ρ is the gap gas volume density, in g / cm 3 , calculated at node Rho_V, generated by the behavioral voltage source B_Rho, whose output is P / 760×1.2, where P is the gap gas pressure.

[0145] 2.1.1.2 Channel holding current

[0146] After the switch S_Ch is initially closed, the gap voltage will drop rapidly and the current will begin to fill the entire loop. In order to maintain the continuity of the closure of the switch S_Ch, it is assumed that there is a minimum current value. When the channel current is greater than the minimum value, there is no need to consider the breakdown delay problem. The switch will continue to close and B_Ch_On will maintain the output at 1V.

[0147] like Fig.15 As shown, the above-mentioned minimum current value is represented by node I_Min, which is generated by the DC voltage source B_I_Min. When the channel current I_Ch is greater than the minimum value, the V(Maintain) output is 1 V. The channel current I_Ch is represented by the voltage V(I_Ch) at the node I_Ch, which is generated by the behavioral current source B_I_Ch, and its output is the absolute value of the channel current.

[0148] The node voltage V(Maintain) is controlled by the behavior voltage source B_Maint, and its output is 1 when the channel current is greater than the minimum current.

[0149] 2.1.2 Channel resistance

[0150] The output of the voltage source B_Res is the product of the current passing through itself and the voltage at the node R_Ch, which represents the channel gap resistance after the gas discharge switch is broken down, in Ω. According to an empirical formula for calculating the channel resistance based on three parameters: gap distance, channel radius and channel current

[0151]

[0152] Where c is the proportionality constant 876, d is the gap distance, i is the channel current, and r is the calculated channel radius in meters;

[0153]

[0154] Where i is the channel current in kA, t is the channel formation time in μs, and is the gap gas density in g / cm3; the formula is used by the current source B_Ch_Rad to drive the voltage at the node Ch_Rad to represent the channel radius.

[0155] like Fig.16 As shown, the circuit is connected in series with a current source B_Ch_Rad and a diode D4 from left to right from the ground node to the node Ch_Rad, and the current source B_Ch_Rad and the diode D4 are also connected in parallel with a capacitor C5 and a resistor R3.

[0156] Where D4 limits the charging of C5 to the peak output of B_Ch_Rad, which is then attenuated by R3. This combination exists because the derivation of the channel radius calculation formula above only considers the channel growth driven by the pulse and does not ignore any contraction or dissipation. At the same time, when the channel is not conducting, a switch controlled by the Ch_On node voltage can be used to keep C6 discharged.

[0157] The above channel radius expression requires the time after arc formation as an input variable; therefore, a timing circuit is added to the model to calculate the time of the last transition of the switch S_Ch from off to on;

[0158] like Fig.16As shown, the timing circuit is composed of a capacitor C6 and a switch S2 connected in series, a node Time is inserted before the switch S2, a node T_C is inserted between the switch S2 and the capacitor C2, and the switch S2 is turned on by the behavior voltage source B_! On, and its output is when V(Ch_On) is greater than 0.5V, the behavior voltage source B_! On drops from 1V to 0V, the switch S2 is disconnected, the capacitor C6 is frozen, and then the voltage of the node T_C is frozen, and the output time is represented by the voltage at the node T_arc, and the node T_arc is driven by the behavior voltage source B_T_Arc, and its output is the simulation time Time minus the voltage V(T_C) at the node T_C.

[0159] The time of the last transition of the switch S_Ch from off to on is represented by the voltage at the node T_arc and is generated in the same way as the overvoltage time described above, using the logical inverse of the node Ch_On voltage as the control signal for the sample and hold circuit that determines the arc start time at the node T_C.

[0160] In order to calculate the channel radius and channel resistance, the time after the channel is closed needs to be taken into account. To achieve this, an additional timing circuit is designed in the model, whose function is to measure the time elapsed from the last transition of the switch S_Ch from off to on. This time interval is inferred by monitoring the voltage change at the node T_arc, and its method is similar to the calculation method described earlier for the time when the gap voltage exceeds the static breakdown voltage. Specifically, the logical negation of the voltage at the node Ch_On is used as the control input of the sample and hold circuit, thus determining the exact moment when the arc is formed at the node T_C.

[0161] The voltage at the node T_arc is driven by a behavioral voltage source B_T_arc, and the output of the behavioral voltage source B_T_arc is the simulation time Time minus the voltage V(T_C) at the node T_C.

[0162] Specifically, when the switch S_Ch is turned off, the voltage at the node Ch_On is 0, the behavior voltage source B_! On outputs the logic negation of the voltage at the node Ch_On, outputs 1, the switch S2 is turned on, the voltage at the node T_C is equal to the voltage at the simulation time Time node, and the node T_arc outputs the voltage 0. When the switch S_Ch is turned on, the voltage at the node Ch_On is 1, the behavior voltage source B_! On outputs the logic negation of the voltage at the node Ch_On, outputs 0, the switch S2 is turned off, the voltage at the node T_C is equal to 0, and the node T_arc outputs the voltage at the Time node

[0163] 2.1.3 Channel Inductance

[0164] In the main circuit, the closed channel inductance is modeled with a behavioral current source B_Ind. After the voltage across the inductor is converted into a current by B_Ind, the current is integrated by capacitor C4. The integration circuit is a behavioral voltage source B_Ch_Rad in parallel with capacitor C4. A node Int_V_L is inserted between the voltage source B_Ch_Rad and capacitor C4. The result of the integration generates a voltage at the node Int_V_L in units of V·S×109. The current generated by B_Ind is then set to the voltage at Int_V_L divided by the voltage at L_Ch to represent the channel inductance in nH. The voltage at node L_Ch is generated by the voltage source B_L_Ch, and its output uses the inductance expression of an isolated thin line in units of nH.

[0165]

[0166] Where: d is the gap distance, in cm; r is the channel radius, in m;

[0167] The output of the voltage source B_L_Ch uses a limiting function limit. This is because when the inductance is too small, the output of the voltage source B_Ind will reach infinity. For a smaller channel radius, an upper limit is set so that the inductance is not too large.

[0168] 2.2 Gas discharge switch circuit model verification and parameter setting

[0169] like Fig.17 As shown, a trigger voltage with a certain amplitude and a certain width is applied to activate switches S3 and S4. Capacitors C7 and C8 have the same initial voltage but opposite direction. When the switch is activated, capacitors C7 and C8 begin to discharge. The lossy transmission line Rg218 is used to simulate the same type of coaxial cable connecting the pulse transmitter and the test unit. L1 and L2 represent the distributed inductance of the pulse generator, and L3-L6 and C9-C12 model the reactive impedance of the test unit components as discrete element transmission lines.

[0170] In LTspice, TRTOL is set to 0.1, the solver is set to Alternate, and the other parameters are kept at the default values. The simulation time is set to 30ns, the gap distance D = 0.64mm, the gas pressure P = 100psig, the gas discharge switch channel distributed capacitance C = 1p, and the initial voltage of capacitors C6 and C7 is scanned using the .step command. The initial value is set to 17.5kV, the step size is 5kV, and the step is 5 times. The measurement result is the gap voltage, that is, the voltage difference between ports T1 and T2.

[0171] like Fig.18As shown, when the pulses arrive at the measuring unit at the same time, a voltage approximately equal to 3.5 times the initial charging voltage of the capacitor appears on the switch, the time it takes for the pulses to arrive at the gas discharge switch is approximately 3ns, the peak duration is approximately 8ns, and the rise and fall times are both approximately 8ns.

[0172] 2.4 Static breakdown suppression module

[0173] The turn-on moment of the gap channel of the gas discharge switch is related to the time when the gap voltage exceeds the static breakdown voltage and the breakdown delay time. The breakdown delay time is determined by the empirical formula proposed above. Its input parameters include node voltages E_Gap and Rho_V. The magnitudes of the two node voltages are related to the gas pressure P, gap distance D and gap voltage V(T1)-V(T2). By using this relationship, the turn-on moment of the gap channel can be controlled by adjusting the parameters P, D and V(T1)-V(T2). However, the premise is to ensure that the gap voltage V_Gap is greater than the static breakdown voltage V_Break of the switch. The static breakdown voltage of the switch increases with the increase of P and D, and a static breakdown suppression module is added here. Fig.19 As shown, the static breakdown suppression module includes a node V_Break_End, and the voltage at the node V_Break_End is generated by a behavioral voltage source B_Brk_End. The output of the behavioral voltage source B_Brk_End is a static breakdown voltage V(V_Break) multiplied by a weakening coefficient r. The output of the node Over becomes a function of judging whether the gap voltage V(V_Gap) is greater than the weakened static breakdown voltage V(V_Break_End). The principle is to introduce a weakening coefficient r. The existence of r makes the gap voltage always greater than the static breakdown voltage. At the same time, the output voltage of the node Over becomes a function of judging whether the voltage at the node V_Gap is greater than the weakened static breakdown voltage V(V_Break_End), thereby ensuring that the switch can be broken down and turned on.

[0174] 2.5 An improved cold cathode trigger tube SPICE model with controllable turn-on delay time

[0175] The gas discharge switch main circuit and the static breakdown voltage weakening module are added to the cold cathode trigger tube trigger gap channel circuit and the gas discharge switch control module respectively to realize the function of controlling the cold cathode trigger tube conduction delay time, such as Fig. 20As shown, the gas discharge switch model circuit and the static breakdown voltage reduction module are respectively inserted into the trigger gap channel circuit and the gas discharge switch model circuit, the gas discharge switch inserted with the static breakdown voltage reduction module is placed between the voltage source V_E_M and the resistor R_MK in parallel, a node M is set between the voltage source V_E_M and the gas discharge switch, the trigger gap circuit is connected to a voltage source B_E_T, and the voltage source output is used to judge whether the current of the resistor R_MK is greater than the minimum current value V(I_Min), if so, the voltage V(M) at the node M is output, if not, 0 is output.

[0176] 2.6 Characteristic parameter test and verification of the improved cold cathode trigger tube SPICE model

[0177] Referring to the cold cathode trigger tube test method of the electronic industry standard of the People's Republic of China, the characteristic parameter test and verification of the constructed improved cold cathode trigger tube SPICE model are carried out. In the simulation, the verification circuit and parameter settings are the same as the aforementioned cold cathode trigger tube model. In the improved cold cathode trigger tube SPICE model with controllable conduction delay time, the gas discharge switch distributed capacitance C is set to 100nF, the diodes D1, D2, and D3 are all 1N5817, and the attenuation coefficient r is set to 0.1. The simulation waveforms of various characteristic parameter tests are shown in the figure below. Figure 21-24 As shown in the figure, it can be seen that the results are similar to the various characteristic parameters of the model before improvement. In order to verify the universality of this improved cold cathode trigger tube, this improved cold cathode trigger tube model was simulated in three mainstream circuit simulation software: Ltspice, Multisim and Pspice.

[0178] Table 2 Improved test results and standard comparison

[0179]

[0180] 2.6.1 Controllable turn-on delay time

[0181] In order to verify the universality of this improved cold cathode trigger tube, the model of this improved cold cathode trigger tube was simulated in three mainstream circuit simulation software: Ltspice, Multisim and Pspice.

[0182] For the improved cold cathode trigger tube SPICE model established above, when the main gap channel applies a DC voltage with an amplitude of 10kV and V_E_M provides a DC voltage with an amplitude of 6kV, the control variable method is used to study the effects of different gap distances and gas pressures on the conduction delay time; when the gas pressure is 1000psig, the gap distance is 3mm, and V_E_M provides a DC voltage with an amplitude of 6kV, the control variable method is used to study the effects of different gap voltages on the conduction delay time. The diode type settings during the simulation verification process are shown in Table 3. Due to software convergence issues, in the Pspice software, the MUR105 model diode is used to verify the effects of the gap voltage of 9kV and 8kV on the conduction delay time; the MUR1560 model diode is used to verify the effects of the gap voltage of 10kV, the gap distance of 5mm, and the gas pressure of 2000psig on the conduction delay time. The rest of the cases are shown in Table 3. The attenuation coefficient r is set to 0.1, and the changes of the switch state and the main gap channel current with the simulation time under three different circuit simulation software are measured as follows: Figure 26-34 shown.

[0183] Table 3 Controllable conduction time simulation verification diode type setting

[0184]

[0185]

[0186] 2.6.2 Conclusion

[0187] According to the above simulation results, when the gas pressure and the gap voltage remain unchanged, the turn-on delay time gradually increases with the increase of the gap distance. When the gap distance is 3mm, 4mm and 5mm, the turn-on delay time is 81.30ns, 223.57ns and 481.71ns respectively; when the gap distance and the gap voltage remain unchanged, the turn-on delay time gradually increases with the increase of the gas pressure. When the gas pressure is 1200psig, 1600psig and 2000psig, the turn-on delay time is 129.67ns, 251.63ns and 450.97ns respectively; when the gas pressure and the gap distance remain unchanged, the turn-on delay time gradually decreases with the increase of the gas pressure. When the gap voltage is 8kV, 9kV and 10kV, the turn-on delay time is 481.58ns, 321.14ns and 223.50ns respectively.

[0188] The present invention proposes and studies a new type of cold cathode trigger tube SPICE model. Under the set parameters, its self-breakdown voltage is 15.51kV, the minimum trigger voltage is 3.00kV, the operating voltage range is 7.03-10.00kV, and the operating current is less than 7.14kA. All characteristic parameters meet the detailed specifications of the RQ-10 cold cathode trigger tube. In view of the uncontrollable turn-on delay time, an improved cold cathode trigger tube model is designed. The gas discharge switch used is constructed based on the gas discharge principle. When the pulses arrive at the measuring unit at the same time, a voltage approximately equal to 3.5 times the initial charging voltage of the capacitor appears on the switch. The time for the pulse to arrive at the switch is about 3ns, the peak duration is about 8ns, and the rise and fall times are both about 8ns.

[0189] The parameter characteristics of this improved model were simulated and verified as above, and the results were similar to the various characteristic parameters of the model before improvement. In order to verify the universality of this improved cold cathode trigger tube, this improved cold cathode trigger tube model was simulated in three mainstream circuit simulation software Ltspice, Multisim and Pspice: the effects of gap distance, gas pressure and gap voltage on the turn-on delay time were simulated under external working voltages of 16kV, 18kV and 20kV, respectively. The simulation results show that the turn-on delay time is proportional to the gap distance and gas pressure, and inversely proportional to the gap voltage. Under the parameter conditions set in this article, the turn-on delay time ranges from 81.30ns to 481.71ns.

[0190] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A cold cathode trigger tube model, characterized in that: It includes a main gap channel circuit, a trigger gap channel circuit and a control module. The main gap channel circuit includes a first circuit simulating a non-working state and a second circuit simulating a working state. In the non-working state, the main gap channel circuit has a large insulation resistance, which is greater than 10MΩ. In the working state, the main gap channel resistance drops to a few tenths of an ohm, which is close to a short-circuit state. The trigger gap channel circuit simulates the process that when the voltage applied at both ends of the main gap channel is lower than the self-breakdown voltage of the trigger tube, if a trigger pulse with a certain amplitude and width is applied to the trigger electrode, the trigger gap between the trigger electrode and the adjacent electrode breaks down and conducts to generate discharge; The control module simulates the self-breakdown voltage of the cold cathode trigger tube and the operating voltage of the cold cathode trigger tube, and limits the operating current range of the cold cathode trigger tube.

2. A cold cathode trigger tube model according to claim 1, characterized in that: The main gap channel circuit includes, from left to right, a first circuit and a second circuit from node A to node K, and an external working voltage acts between the node A and the node K; The first circuit includes a resistor R_Off and an inductor L_Off connected in series, and also includes a capacitor C_Off connected in parallel with the resistor R_Off and the inductor L_Off; The second circuit includes a resistor R_On, an inductor L_On, a voltage-controlled switch S_Open, a shunt switch D1 from left to right, and a behavior voltage source B_E_On connected in series, and also includes a capacitor C_On connected in parallel with the resistor R_On and the inductor L_On, a shunt switch D2 and a behavior voltage source B_E_FwBreak connected in series from left to right, and a shunt switch diode D1 and a behavior voltage source B_E_On connected in parallel, a behavior voltage source B_E_ReBreak connected in series, and a shunt switch D3 from right to left, and a shunt switch diode D1 and a behavior voltage source B_E_On connected in parallel, The voltage-controlled switch S_Open is turned on or off by the node Open, a node FwBreak is set between the shunt switch D2 and the behavior voltage source B_E_FwBreak, and a node ReBreak is set between the behavior voltage source B_E_ReBreak and the shunt switch D3; The trigger gap channel circuit includes, from left to right, a flow control switch W1, a resistor R_Tk and an inductor L_Tk connected in series from node T to node K, and also includes a capacitor C_Tk connected in parallel with the resistor R_Tk and the inductor L_Tk; The control module includes a self-breakdown voltage control module, an operating voltage control module and an operating current limiting module; The self-breakdown voltage control module includes a DC voltage source V_P with one end grounded and the other end set at a node V_P, a DC voltage source V_D with one end grounded and the other end set at a node V_D, and a DC voltage source V_A with one end grounded and the other end set at a node V_A, and the DC voltage source V_P, the DC voltage source V_D and the DC voltage source V_A are respectively connected in parallel with a resistor V_P, a resistor V_D and a resistor V_A at both ends of each of the DC voltage source V_P, the DC voltage source V_D and the DC voltage source V_A; The working voltage control module includes a behavior voltage source B_Ctrl with one end grounded and the other end connected to the Ctrl node, a resistor R_Ctrl is connected in parallel at both ends of the behavior voltage source B_Ctrl, a behavior voltage source B_Tril, a current source G_Omin in the form of TBL and a resistor R_Omin are connected in series with each other at both ends to form a loop, and also includes a behavior voltage source B_Tmin with one end grounded and the other end connected to the Tmin node, and a resistor R_Tmin is connected in parallel at both ends of the behavior voltage source B_Tmin; The working current limiting module comprises a behavior voltage source B_Open with one end grounded and the other end connected to an Open node, and resistors R_Open are connected in parallel at both ends of the behavior voltage source B_Open.

3. An improved model of a cold cathode trigger tube capable of controlling the turn-on delay time, comprising any one of the cold cathode trigger tube models described in claims 1-2, characterized in that: It also includes a gas discharge switch model circuit, which is added to the trigger gap channel circuit and used as a switch device to control the conduction delay time.

4. The improved model of a cold cathode trigger tube capable of controlling the conduction delay time according to claim 3, characterized in that: The gas discharge switch circuit is connected in series with a behavioral current source B_Ind, a voltage-controlled switch S_Ch and a behavioral voltage source B_Res from node T1 to node T2, and also includes a capacitor C_Cap connected in parallel with the behavioral current source B_Ind, the voltage-controlled switch S_Ch and the behavioral voltage source B_Res.

5. The improved model of a cold cathode trigger tube capable of controlling the conduction delay time according to claim 4, characterized in that: The breakdown of the gas discharge switch is equivalent to the conduction of the voltage-controlled switch S_Ch, and the voltage-controlled switch S_Ch is controlled to be turned on or off by the gap switch control circuit connected to the node Ch_On.

6. The improved model of a cold cathode trigger tube capable of controlling the conduction delay time according to claim 5, characterized in that: In the gap switch control circuit, the voltage-controlled switch S_Ch is turned on or off by the voltage source B_Ch_On, the voltage source B_Ch_On is connected to the node Ch_On, and its output is determined by the OR logic composed of the node voltage V(Delay_Ovre) and the node voltage V(Maintain), if any one of V(Delay_Ovre) and V(Maintain) is greater than 0.5, then the output of B_Ch_On is 1, the switch S_Ch is turned on, the voltage source B_Ch_On is also connected in series with the voltage source B_Ch_On, and a capacitor C1 is connected in parallel with the voltage source B_Ch_On and the voltage source B_Ch_On; The node voltage V(Delay_Ovre) is controlled by the behavior voltage source B_Dly_Ovr to output a value, and its output is true if the node voltage V(T_Over) is greater than the node voltage V(Delay), and the output is 1. The node voltage V(T_Over) indicates the time when the gap voltage exceeds the static breakdown voltage, and the node voltage V(Delay) indicates the breakdown delay time; The V(T_Over) is generated by the behavior voltage source B_T_Ovr, and its output is the simulation time Time minus the voltage value V(T_B) of the node T_B, in seconds. The circuit of the simulation time is composed of the behavior voltage source B_Time, the switch S1 and the capacitor C2 connected in series to form a loop. The node Time is inserted between the behavior voltage source B_Time and the switch S1. The node output is controlled by the behavior voltage source B_Time to output the simulation time Time. The node T_B is inserted between the switch S1 and the capacitor C2. The switch S1 is turned on by the behavior voltage source B_! Ovr. Its output is that when V(Over) is greater than 0.5V, the behavior voltage source B_! Ovr drops from 1V to 0V, the switch S1 is disconnected, the capacitor C2 is frozen, and then the voltage of the node T_B is frozen; The voltage value V(Over) of the node Over is provided by the voltage source B_Ovr, whose output is an If judgment statement. If the gap voltage is greater than the static breakdown voltage, the output is 1 when true, otherwise it is 0. When the judgment is true, the tanh function is used to smooth the transition of the switch S1 from the off state to the on state; The size of the gap voltage is controlled by the voltage V(V_Gap) at the node V_Gap, which is generated by the behavioral voltage B_V_Gap, and its output is the absolute value of the voltage difference between T1 and T2. The size of the static breakdown voltage is controlled by the voltage V(V_Break) at the node V_Break, which is generated by the behavioral voltage B_V_Break, and its output is an empirical formula: The unit is kV; V(Delay) is generated by the behavioral voltage source B_Dly, and its output is the empirical formula: Where: E is the gap electric field, in KV / cm, calculated by the node E_Gap, generated by the behavioral voltage source B_E_Gap, whose output is the ratio of the node voltage V(V_Gap) to the channel gap D, ρ is the gap gas volume density, in g / cm 3 , calculated at node Rho_V, generated by the behavioral voltage source B_Rho, whose output is P / 760×1.2, where P is the gap gas pressure. The node voltage V(Maintain) is controlled by the behavioral voltage source B_Maint. When the channel current is greater than the minimum current value, the output of V(Maintain) is 1. The minimum current value is represented by the voltage V(I_Min) at the node I_Min, which is generated by the DC voltage source B_I_Min. The channel current is represented by the voltage V(I_Ch) at the node I_Ch, which is generated by the behavioral current source B_I_Ch. The output is the absolute value of the channel current.

7. The improved model of a cold cathode trigger tube capable of controlling the conduction delay time according to claim 3, characterized in that: The output value of the behavioral voltage source B_Res is the product of the current passing through itself and the voltage at the node R_Ch, which represents the channel gap resistance after the gas discharge switch is broken down. The output value of the behavioral voltage source B_Res is based on a formula for calculating the channel resistance: Where c is the proportional constant 876, d is the gap distance, i is the channel current, and r is the channel radius in meters; The channel radius formula is: Wherein i is the channel current, in kV, t is the channel formation time, in μs, ρ is the gap gas density, in g / cm3, the channel radius formula drives the voltage at the node Ch_Rad through the current source B_Ch_Rad, and the circuit is connected in series from the ground node to the node Ch_Rad with the current source B_Ch_Rad and the diode D4 from left to right, and the current source B_Ch_Rad and the diode D4 are also connected in parallel with the capacitor C5 and the resistor R3; The discharge switch model circuit also includes a timing circuit for calculating the time of the last transition of the switch S_Ch from off to on, The timing circuit is composed of a capacitor C6 and a switch S2 connected in series, a node Time is inserted before the switch S2, a node T_C is inserted between the switch S2 and the capacitor C2, the switch S2 is controlled to be turned on by the behavior voltage source B_! On, and its output is that when V(Ch_On) is greater than 0.5V, the behavior voltage source B_! On drops from 1V to 0V, the switch S2 is disconnected, the capacitor C6 is frozen, and then the voltage of the node T_C is frozen, and the output time is represented by the voltage at the node T_arc, the node T_arc is driven by the behavior voltage source B_T_Arc, and its output is the simulation time Time minus the voltage V(T_C) at the node T_C; After the voltage across the inductor is converted into current by the behavioral current source B_Ind, the current is integrated by the capacitor C4. The integration circuit is a behavioral voltage source B_Ch_Rad connected in parallel with the capacitor C4. A node Int_V_L is inserted between the voltage source B_Ch_Rad and the capacitor C4. The integration result generates a voltage at the node Int_V_L. The current generated by the behavioral current source B_Ind is set to the voltage V(Int_V_L) generated at the node Int_V_L divided by the voltage V(L_Ch) at the node L_Ch. The voltage at the node L_Ch is generated by the behavioral voltage source B_L_Ch. The output of the voltage source B_L_Ch is the inductance expression: Wherein d is the gap distance, r is the channel radius, and the output of the voltage source B_L_Ch adopts the limiting function limit.

8. The improved model of a cold cathode trigger tube capable of controlling the conduction delay time according to claim 6, characterized in that: The gap switch control circuit also includes a static breakdown weakening module, and the static breakdown suppression module includes a node V_Break_End. The voltage at the node V_Break_End is generated by a behavioral voltage source B_Brk_End. The output of the behavioral voltage source B_Brk_End is a static breakdown voltage V(V_Break) multiplied by a weakening coefficient r. The output of the node Over becomes a method for determining whether the gap voltage V(V_Gap) is greater than the weakened static breakdown voltage V(V_Break_End).

9. The improved model of a cold cathode trigger tube capable of controlling the conduction delay time according to any one of claims 3 to 8, characterized in that: The gas discharge switch model circuit and the static breakdown voltage reduction module are respectively inserted into the trigger gap channel circuit and the gas discharge switch model circuit, the gas discharge switch inserted with the static breakdown voltage reduction module is placed between the voltage source V_E_M and the resistor R_MK in parallel, a node M is set between the voltage source V_E_M and the gas discharge switch, the trigger gap circuit is connected with a voltage source B_E_T, and the output of the voltage source is to judge whether the current of the resistor R_MK is greater than the minimum current value V(I_Min), if so, the voltage V(M) at the node M is output, if not, 0 is output.

Images