A phase-controlled switch design method for a dynamic mold system and related components

Abstract

The present invention discloses a phase-controlled switch design method and related components of a dynamic model system. The scheme is applied to a dynamic model system of a distribution network. After receiving a start signal, when the AC voltage of the fault phase set by the user is detected to pass through the zero point, the conduction of the bidirectional thyristor module connected to the fault phase is controlled after the fault trigger time has passed, so as to realize the grounding of the fault phase. It can be seen that since the conduction time of the thyristor is short, the delay time when controlling the conduction of the bidirectional thyristor module is very short. In addition, the conduction time of the bidirectional thyristor module can be accurately controlled through real-time zero-crossing detection, which further improves the control accuracy of the bidirectional thyristor module, thereby realizing the fault simulation of the dynamic model system of the distribution network.

Description

Technical Field

[0001] The present invention relates to the control field of a moving mold system, and in particular to a phase-controlled switch design method and related components of a moving mold system. Background Art

[0002] The neutral point grounding method of my country's distribution network is a small current grounding system. In the small current grounding system, the probability of single-phase grounding fault is the highest. Since its fault characteristics are affected by multiple factors such as system capacity, system imbalance, fault initial phase angle and fault transition resistance, its fault characteristics are quite complex. Therefore, the handling of single-phase grounding faults has always been a technical problem in the operation of distribution networks. In addition, the occurrence of single-phase grounding faults may damage the insulation of equipment, or cause fires or even personal injury. The new version of the "Technical Guidelines for Distribution Networks" Q / GDW10370-2016 requires that permanent single-phase grounding faults should be quickly isolated nearby. This places high demands on the single-phase grounding fault handling performance of the primary and secondary integrated equipment. Therefore, how to ensure the correctness of the equipment's operation after being connected to the network needs to be solved urgently.

[0003] The dynamic simulation system of the distribution network adopts the proportional simulation idea to simulate the operating characteristics of the distribution network. It can flexibly connect to the primary and secondary equipment to carry out the verification of the single-phase grounding fault handling function. In recent years, it has been widely used in various electrical research institutes and testing units. The single-phase grounding fault characteristics of the distribution network are closely related to factors such as the initial phase angle of the fault. This makes it urgent to study a high-precision phase-controlled switch to set the initial phase angle of the fault to accurately simulate the single-phase grounding fault of the distribution network.

[0004] At present, most of the phase-controlled switches used in dynamic model systems are realized by delaying the action of AC contactors or permanent magnet fast switches. However, since the switching action time of AC contactors or permanent magnet fast switches is somewhat discrete, it is impossible to determine the exact delay time of the current AC contactor or permanent magnet fast switch action, and the delay time has a certain relationship with the voltage phase at the triggering moment. Therefore, the simulation effect of single-phase fault grounding of the dynamic model system of the distribution network relying on AC contactors or permanent magnet fast switches is less accurate. Summary of the invention

[0005] The purpose of the present invention is to provide a phase-controlled switch design method and related components of a dynamic model system. Since the conduction time of the thyristor is short, the delay time when controlling the conduction of the bidirectional thyristor module is very short. In addition, the conduction time of the bidirectional thyristor module can be accurately controlled through real-time zero-crossing point detection, which further improves the control accuracy of the bidirectional thyristor module, thereby realizing fault simulation of the dynamic model system of the distribution network.

[0006] In order to solve the above technical problems, the present invention provides a phase-controlled switch design method for a dynamic mold system, which is applied to a distribution network dynamic mold system, wherein a bidirectional thyristor module is respectively provided between each phase output terminal and a ground terminal of the distribution network dynamic mold system, and the method comprises:

[0007] Performing real-time zero-crossing detection on each phase of the AC voltage of the power distribution network dynamic model system;

[0008] Determine the fault trigger time based on the zero-crossing point detection and the fault occurrence initial phase angle of the fault phase of the dynamic model system of the power distribution network set by the user;

[0009] Determine whether a start signal is received;

[0010] If yes, when the fault trigger time has passed after the AC voltage of the fault phase passes through the zero point, the bidirectional thyristor module connected to the fault phase is controlled to be turned on so that the fault phase is grounded;

[0011] After the fault duration set by the user has elapsed, the bidirectional thyristor module is controlled to be turned off.

[0012] Preferably, before determining the fault trigger time based on the zero-crossing point detection and the fault occurrence initial phase angle of the fault phase of the dynamic model system of the power distribution network set by the user, the method further includes:

[0013] Receive the fault phase setting of the power distribution network dynamic model system, the fault initial phase angle setting of the fault phase and the fault duration setting sent by the user through the human-computer interaction control device.

[0014] Preferably, a circuit breaker is provided between each phase output end of the power distribution network dynamic model system and the bidirectional thyristor module;

[0015] The human-machine interaction control device is also used to control the closing of each of the circuit breakers before sending the fault phase setting of the distribution network dynamic model system, the initial phase angle setting of the fault phase, and the fault duration setting; and to control the opening of each of the circuit breakers when an overcurrent fault occurs in the distribution network dynamic model system.

[0016] Preferably, after determining the fault trigger time based on the zero-crossing point detection and the fault occurrence initial phase angle of the fault phase of the dynamic model system of the power distribution network set by the user, the method further includes:

[0017] Set the timing time of the timer to the fault trigger time;

[0018] When the fault trigger time has passed after the AC voltage of the fault phase passes through a zero point, controlling the bidirectional thyristor module connected to the fault phase to be turned on so that the fault phase is grounded, including:

[0019] When the AC voltage of the fault phase passes through a zero point, the timer is controlled to be enabled so that the timer starts timing;

[0020] After receiving the timing end signal sent by the timer, the bidirectional thyristor module connected to the fault phase is controlled to be turned on, so that the fault phase is grounded.

[0021] Preferably, each phase of the power distribution network dynamic model system is respectively provided with a zero-crossing detection circuit for real-time detection of the zero-crossing point of the corresponding one-phase AC voltage in the power distribution network dynamic model system, and sending a zero-crossing signal when the zero-crossing point is detected;

[0022] Performing real-time zero-crossing detection on each phase AC voltage of the power distribution network dynamic model system includes:

[0023] Receiving the zero-crossing signal sent by each of the zero-crossing detection circuits to perform real-time zero-crossing detection on each phase of the AC voltage of the power distribution network dynamic model system;

[0024] The zero-crossing detection circuit includes a comparator, wherein the positive input terminal of the comparator is grounded, and the negative input terminal is connected to the secondary AC voltage of one phase corresponding to itself in the distribution network dynamic model system, and is used to output a negative level when the amplitude of the secondary AC voltage of one phase corresponding to itself in the distribution network dynamic model system is positive, and output a positive level when the amplitude of the secondary AC voltage of one phase corresponding to itself in the distribution network dynamic model system is negative. When the secondary AC voltage of one phase corresponding to itself in the distribution network dynamic model system passes through zero, a rising edge signal or a falling edge signal is output, and the rising edge signal or the falling edge signal is the zero-crossing signal.

[0025] Preferably, after receiving the zero-crossing signal sent by each of the zero-crossing detection circuits to perform real-time zero-crossing detection on each phase AC voltage of the power distribution network dynamic model system, the method further includes:

[0026] Determine whether the time difference between the time when the zero-crossing signal is received this time and the time when the zero-crossing signal was received last time is within a preset range;

[0027] If so, the step of determining the fault trigger time based on the zero-crossing point detection and the fault initial phase angle of the fault phase of the dynamic model system of the distribution network set by the user is entered.

[0028] Preferably, the control end of each bidirectional thyristor module is respectively connected to a thyristor trigger circuit;

[0029] Controlling the bidirectional thyristor module connected to the fault to be turned on, comprising:

[0030] Outputting a PWM flag enable signal, and controlling the control end of the thyristor trigger circuit corresponding to the bidirectional thyristor module connected to the fault to be enabled, and outputting a PWM waveform through the control end of the thyristor trigger circuit, so that the thyristor trigger circuit drives the bidirectional thyristor module connected to the fault to be turned on;

[0031] After a fault duration set by a user has elapsed, the bidirectional thyristor module is controlled to be turned off, comprising:

[0032] Stop outputting the PWM flag enable signal, and stop controlling the control end enable of the thyristor trigger circuit corresponding to the bidirectional thyristor module connected to the fault, so that the thyristor trigger circuit drives the bidirectional thyristor module connected to the fault to turn off.

[0033] Preferably, the power distribution network dynamic model system further comprises a current detection device for detecting a loop current in the power distribution network dynamic model system;

[0034] The method further comprises:

[0035] If it is detected that the loop current in the dynamic mode system of the power distribution network is greater than the overcurrent protection current, each of the bidirectional thyristor modules is controlled to be turned off.

[0036] Preferably, the bidirectional thyristor module includes a positive half-cycle conducting thyristor and a negative half-cycle conducting thyristor;

[0037] The first end of the positive half-cycle conducting thyristor is connected to the second end of the negative half-cycle conducting thyristor, and is connected to the corresponding one-phase output end of the power distribution network dynamic model system; the second end of the positive half-cycle conducting thyristor is connected to the first end of the negative half-cycle conducting thyristor, and is connected to the ground end;

[0038] Controlling the bidirectional thyristor module connected to the fault to be turned on, comprising:

[0039] The bidirectional thyristor module connected to the fault phase is controlled to be turned on, so that when the AC voltage of the fault phase is in a positive half cycle, the fault phase is grounded by turning on the thyristor in the positive half cycle, and when the AC voltage of the fault phase is in a negative half cycle, the fault phase is grounded by turning on the thyristor in the negative half cycle.

[0040] Preferably, the fault triggering time is determined based on the zero-crossing point detection and the fault occurrence initial phase angle of the fault phase of the dynamic model system of the power distribution network set by the user, including:

[0041] Determine the fault trigger time through a time calculation formula based on the zero-crossing point detection and the fault initial phase angle of the fault phase of the dynamic model system of the power distribution network set by the user;

[0042] The time calculation formula is:

[0043]

[0044] Wherein, T is the fault triggering time, An initial phase angle for the fault;

[0045] The fault triggering time is the time from detecting the zero crossing point to controlling the bidirectional thyristor module connected to the fault to be turned on.

[0046] In order to solve the above technical problems, the present invention provides a phase-controlled switch design system of a dynamic mold system, which is applied to a dynamic mold system of a power distribution network. A bidirectional thyristor module is provided between each phase output terminal and a ground terminal of the dynamic mold system of the power distribution network. The phase-controlled switch design system of the dynamic mold system comprises:

[0047] A detection unit, used for performing real-time zero-crossing detection on each phase AC voltage of the power distribution network dynamic model system;

[0048] A determination unit, configured to determine a fault trigger time based on the zero-crossing point detection and a fault occurrence initial phase angle of a fault phase of the dynamic model system of the power distribution network set by a user;

[0049] A judging unit, used to judge whether a start signal is received;

[0050] A first control unit is used for controlling the bidirectional thyristor module connected to the fault phase to be turned on after receiving a start signal and detecting that the AC voltage of the fault phase passes through a zero point and the fault trigger time has passed, so as to ground the fault phase;

[0051] The second control unit is used to control the bidirectional thyristor module to turn off after a fault duration set by a user has elapsed.

[0052] In order to solve the above technical problems, the present invention provides a phase-controlled switch design device for a moving mold system, comprising:

[0053] Memory for storing computer programs;

[0054] A processor is used to implement the steps of the phase-controlled switch design method of the dynamic mold system as described above when executing the computer program.

[0055] The present application provides a phase-controlled switch design method and related components for a dynamic model system. The scheme is applied to a dynamic model system of a distribution network. After receiving a start signal, when the AC voltage of the fault phase set by the user is detected to pass through the zero point, the conduction of the bidirectional thyristor module connected to the fault phase is controlled after the fault trigger time, so as to achieve grounding of the fault phase. It can be seen that due to the short conduction time of the thyristor, the delay time when controlling the conduction of the bidirectional thyristor module is very short. In addition, the conduction time of the bidirectional thyristor module can be accurately controlled through real-time zero-crossing detection, which further improves the control accuracy of the bidirectional thyristor module, thereby achieving fault simulation of the dynamic model system of the distribution network. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0057] Figure 1 A schematic flow chart of a phase-controlled switch design method for a dynamic mold system provided by the present invention;

[0058] Figure 2 A schematic diagram of the structure of a zero-crossing detection circuit provided by the present invention;

[0059] Figure 3 A schematic structural diagram of a thyristor trigger circuit provided by the present invention;

[0060] Figure 4 The present invention provides a structural schematic diagram of a phase-controlled switch design system for a moving mold system;

[0061] Figure 5 The present invention provides a structural schematic diagram of a phase-controlled switch design device for a moving mold system. DETAILED DESCRIPTION

[0062] The core of the present invention is to provide a phase-controlled switch design method and related components for a dynamic model system. Since the conduction time of the thyristor is short, the delay time when controlling the conduction of the bidirectional thyristor module is very short. In addition, the conduction time of the bidirectional thyristor module can be accurately controlled through real-time zero-crossing point detection, which further improves the control accuracy of the bidirectional thyristor module, thereby realizing fault simulation of the dynamic model system of the distribution network.

[0063] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] Please refer to Figure 1 , Figure 1 A flow chart of a phase-controlled switch design method for a dynamic model system provided by the present invention is provided. The method is applied to a dynamic model system of a power distribution network. A bidirectional thyristor module is provided between each phase output terminal and a ground terminal of the dynamic model system of the power distribution network. The method comprises:

[0065] S11: Perform real-time zero-crossing detection on each phase AC voltage of the dynamic model system of the distribution network;

[0066] In this embodiment, the applicant considers that in the prior art, when simulating a single-phase grounding fault of a distribution network dynamic model system, an AC contactor or a permanent magnet fast switch is usually set between the output terminal and the grounding terminal of the distribution network dynamic model system, and the AC contactor or the permanent magnet fast switch connected to a certain phase of the distribution network dynamic model system is controlled to close, thereby achieving single-phase grounding of the distribution network dynamic model system. However, due to the action delay of the AC contactor or the permanent magnet fast switch, the prior art cannot accurately control the AC contactor or the permanent magnet fast switch to close at the desired time. Although the AC contactor or the permanent magnet fast switch can be closed at the desired time by setting the delay time, the delay time of the AC contactor or the permanent magnet fast switch is discrete, that is, the delay time of the AC contactor or the permanent magnet fast switch is not fixed. Each time the delay time of the AC contactor or the permanent magnet fast switch is set, the delay time needs to be reset, which will lead to a decrease in work efficiency, and each time the delay time is adjusted, debugging is required, and the debugging process is also relatively complicated, which is not convenient for users to implement fault simulation.

[0067] In order to solve the above technical problems, in this application, the AC contactor or permanent magnet fast switch is first replaced with a bidirectional thyristor module. Since the conduction time of the thyristor is short and almost negligible, even if it is necessary to adjust its delay time to control the conduction of the bidirectional thyristor at the desired time, there is no need for multiple debugging.

[0068] In addition, the present application also performs real-time zero-crossing detection on each phase of the AC voltage of the distribution network dynamic model system, thereby obtaining the phase of each phase of the AC voltage of the distribution network dynamic model system in real time, thereby facilitating the subsequent control of the bidirectional thyristor module to be turned on at the desired time, that is, controlling the bidirectional thyristor module to be turned on at the initial phase angle of the fault phase set by the user.

[0069] S12: Determine the fault triggering time based on the zero-crossing point detection and the fault initial phase angle of the fault phase of the dynamic model system of the distribution network set by the user;

[0070] The zero-crossing point detection can detect the zero-crossing point of the fault phase set by the user. The zero-crossing point of the fault phase and the fault occurrence phase angle of the fault phase can determine that the fault phase reaches the fault occurrence initial phase angle of the fault phase after the zero-crossing point and the fault trigger time. That is, after the zero-crossing point of the fault phase is detected and the fault trigger time has passed, the bidirectional thyristor module corresponding to the fault is controlled to be turned on, so as to achieve grounding of the fault phase at the fault occurrence initial phase angle of the fault phase.

[0071] S13: Determine whether a start signal is received;

[0072] After calculating the fault trigger time, it is determined whether a start signal is received. The start signal can be a start signal sent immediately by the user, or a timer set in advance by the user through a timer, such as causing a start signal sending device to send a start signal at a preset time. If the start signal is not received, the bidirectional thyristor module is not controlled to be turned on in this application, but the zero-crossing detection is continuously performed.

[0073] S14: If a start signal is received, when the fault trigger time has passed after the AC voltage of the fault phase passes through the zero point, the bidirectional thyristor module connected to the fault phase is controlled to be turned on to ground the fault phase;

[0074] If the start signal is received, it means that the bidirectional thyristor module can be controlled to conduct at this time, and it is judged whether the zero crossing point is detected. If the zero crossing point is detected, the timing of the fault trigger time is started, and when the fault trigger time passes after the zero crossing point is detected, the bidirectional thyristor module connected to the fault phase is controlled to conduct. Thus, the fault phase is grounded at the initial phase angle of the fault in the fault phase.

[0075] S15: After the fault duration set by the user has passed, the bidirectional thyristor module is controlled to be turned off.

[0076] In addition, the user also sets the fault duration, that is, the grounding time of the fault phase, which starts timing after the bidirectional thyristor module connected to the fault phase is turned on. If the fault duration has passed, the bidirectional thyristor module is controlled to be turned off to stop the grounding of the fault phase.

[0077] It should be noted that the fault duration in the present application is not limited to a specific time, as long as it meets the needs of the user.

[0078] In addition, when the bidirectional thyristor module is controlled based on the fault initial phase angle of the fault phase set by the user, the fault initial phase angle of the fault phase can also be adjusted according to the actual detection results during zero-crossing detection to achieve precise control. This application does not limit the specific implementation.

[0079] Of course, the method in this application can be widely used in 400V, 690V, 800V and 1000V dynamic model systems, and this application does not limit this. This application can also be used for the construction of a multi-state single-phase grounding fault simulation scenario such as a real-type test field of a 10kV voltage level distribution network or a dynamic model system with different fault phases and different initial phase angles of the fault through the optimization of high-power thyristors and control methods.

[0080] A temperature detection module can also be provided in the present application to detect the temperature of the bidirectional thyristor module to avoid damage to the thyristor due to excessive thyristor temperature. When a high thyristor temperature is detected, the speed of the fan can be controlled to increase to cool the thyristor.

[0081] The fault phase is phase A, phase B or phase C of the dynamic model system of the distribution network. The initial phase angle of the fault can be set in the range of 0-360°, with a minimum resolution of 0.1°. The minimum resolution when setting the fault duration is 1ms, and the specific duration is not limited.

[0082] In summary, since the conduction time of the thyristor in the present application is short, the delay time when controlling the conduction of the bidirectional thyristor module is very short. In addition, the conduction time of the bidirectional thyristor module can be accurately controlled through real-time zero-crossing point detection, which further improves the control accuracy of the bidirectional thyristor module, thereby realizing fault simulation of the dynamic model system of the distribution network.

[0083] Based on the above embodiments:

[0084] As a preferred embodiment, before determining the fault trigger time based on the zero-crossing point detection and the fault initial phase angle of the fault phase of the dynamic model system of the distribution network set by the user, it also includes:

[0085] The fault phase setting, the initial phase angle setting of the fault phase and the fault duration setting of the dynamic model system of the distribution network sent by the user through the human-machine interactive control device are received.

[0086] In this embodiment, before performing zero-crossing detection, it is necessary to first receive the user's setting information, such as the fault phase setting of the distribution network dynamic model system, the initial phase angle setting of the fault phase, and the fault duration setting, and the above information is sent by the user through the human-computer interaction control device. After the user makes corresponding settings on the human-computer interaction control device, the human-computer interaction control device sends the setting information to the processor in this application through the bus module, so that the processor in this application can perform corresponding zero-crossing detection, fault trigger time calculation, and control of the bidirectional thyristor, etc.

[0087] In addition, the human-computer interaction control device in the present application may also include but is not limited to an LCD (Liquid Crystal Display) display module, which is used to display the voltage, current and operating status of the distribution network dynamic model system, so that the user can promptly know the status of the distribution network dynamic model system, and enable the user to perform protective operations in time when a fault occurs in the distribution network dynamic model system. It has the characteristics of reliability, convenience and high precision.

[0088] The human-machine interaction control device may include, but is not limited to, an MCU (Microcontroller Unit), and the processor may also be, but is not limited to, an MCU.

[0089] When the human-machine interactive control device and the processor are connected, they can be connected through a bus module, but not limited to. The bus module is mainly used for data transmission and signal synchronization between the human-machine interactive control device and the processor, including bus signals composed of 485 transceiver signals S_RXD, S_TXD, clock synchronization signal S_CLK and interrupt signal S_INT, etc., wherein S_RXD and S_TXD are data transceiver signals, which realize the sending of setting parameters (such as the setting of fault phase and related parameters) and the collection of voltage, current amplitude and processor operation status; wherein, the user can start the setting through the timer inside the human-machine interactive control device, such as setting the output of the start signal to the processor at a preset time, or sending the start signal to the processor through the human-machine interactive control device at the current time, when the immediate start signal is received or the timing of the start signal is reached, the clock synchronization signal S_CLK will generate a falling edge, and the processor will enter the corresponding interrupt processing function after collecting the falling edge signal to perform relevant calculations and controls. Among them, the interrupt processing function is to calculate the fault trigger time later, and perform zero crossing detection and other processing.

[0090] In addition, the human-machine interaction control device may further include a time synchronization module to synchronize the timer of the human-machine interaction control device based on a GPS (Global Positioning System) signal to ensure the accuracy of each signal when it is generated.

[0091] The human-computer interaction control device may also include a communication module, which is composed of a network port and a serial port, to facilitate the integrated development and remote control in this application.

[0092] As a preferred embodiment, a circuit breaker is provided between each phase output end of the power distribution network dynamic model system and the bidirectional thyristor module;

[0093] The human-machine interactive control device is also used to control the closing of each circuit breaker before sending the fault phase setting, the initial phase angle setting of the fault phase and the fault duration setting of the distribution network dynamic model system; and to control the opening of each circuit breaker when an overcurrent fault occurs in the distribution network dynamic model system.

[0094] The applicant has taken into consideration that when single-phase grounding occurs, there may be faults such as overcurrent in the dynamic model system of the distribution network. If the above faults occur, the components in the dynamic model system of the distribution network may be burned out, causing the dynamic model system of the distribution network to fail to work normally.

[0095] In order to solve the above technical problems, the present application also provides a circuit breaker arranged between each phase output end of the distribution network dynamic model system and the bidirectional thyristor module. Before the single-phase grounding fault simulation, that is, before sending the fault phase setting of the distribution network dynamic model system, the initial phase angle setting of the fault phase and the fault duration setting to the processor, the human-computer interaction control device first controls the closing of each circuit breaker, thereby ensuring that the fault phase of the distribution network dynamic model system can be grounded, and controls each circuit breaker to be disconnected when an overcurrent fault is detected in the distribution network dynamic model system, so that the fault phase of the distribution network dynamic model system is disconnected and grounded, thereby ensuring the normal operation of the distribution network dynamic model system.

[0096] In addition, if there is no overcurrent fault in the dynamic model system of the distribution network, the synchronous control circuit breaker is disconnected when the single-phase grounding fault simulation ends, that is, when the bidirectional thyristor circuit is disconnected.

[0097] As a preferred embodiment, after determining the fault trigger time based on the zero-crossing point detection and the fault occurrence initial phase angle of the fault phase of the dynamic model system of the distribution network set by the user, it also includes:

[0098] Set the timer to the fault trigger time;

[0099] When the fault trigger time has passed after the AC voltage of the fault phase passes through the zero point, the bidirectional thyristor module connected to the fault phase is controlled to be turned on to ground the fault phase, including:

[0100] When the AC voltage of the fault phase passes through zero, the timer is controlled to be enabled so that the timer starts timing;

[0101] After receiving the timing end signal sent by the timer, the bidirectional thyristor module connected to the fault phase is controlled to be turned on to ground the fault phase.

[0102] In this embodiment, when the zero crossing point of the fault phase is detected after receiving the start signal, the bidirectional thyristor module connected to the fault phase can be controlled to be turned on only after the fault trigger time has passed. Based on this, a timer is set in the present application, and the timing time of the timer is the fault trigger time. When the zero crossing point of the fault phase is detected after receiving the start signal, the timer is controlled to be enabled, and the timer starts timing. After the timing time of the timer reaches the fault trigger time, the timer will send a timing time end signal to the processor, and at this time, the processor controls the bidirectional thyristor connected to the fault phase to be turned on, so as to realize the grounding of the fault phase at the initial phase angle of the fault.

[0103] By setting the timing of the timer, the processor can ensure that the initial phase angle of the fault after detecting the zero crossing point of the fault phase controls the grounding of the fault phase, thereby ensuring the punctuality of the control and reducing the resource occupation of the processor.

[0104] As a preferred embodiment, each phase of the power distribution network dynamic model system is respectively provided with a zero-crossing detection circuit for real-time detection of the zero-crossing point of the corresponding one-phase AC voltage in the power distribution network dynamic model system, and sending a zero-crossing signal when the zero-crossing point is detected;

[0105] Real-time zero-crossing detection of each phase AC voltage of the distribution network dynamic model system, including:

[0106] Receive the zero-crossing signal sent by each zero-crossing detection circuit to perform real-time zero-crossing detection on each phase AC voltage of the power distribution network dynamic model system;

[0107] The zero-crossing detection circuit includes a comparator, wherein the positive input terminal of the comparator is grounded, and the negative input terminal is connected to the secondary AC voltage of one phase corresponding to itself in the distribution network dynamic model system. The comparator is used to output a negative level when the amplitude of the secondary AC voltage of one phase corresponding to itself in the distribution network dynamic model system is positive, and to output a positive level when the amplitude of the secondary AC voltage of one phase corresponding to itself in the distribution network dynamic model system is negative. The comparator outputs a rising edge signal or a falling edge signal when the secondary AC voltage of one phase corresponding to itself in the distribution network dynamic model system passes through a zero point. The rising edge signal or the falling edge signal is a zero-crossing signal.

[0108] In order to detect the zero crossing point of each phase AC voltage in the dynamic model system of the power distribution network, please refer to the zero crossing detection circuit in this embodiment. Figure 2 , Figure 2The present invention provides a schematic diagram of the structure of a zero-crossing detection circuit, in which the positive input terminal of the comparator is grounded, and the negative input terminal is connected to the secondary AC voltage of a phase corresponding to itself in the distribution network dynamic model system. When the amplitude of the secondary AC voltage of a phase corresponding to itself in the distribution network dynamic model system is positive, that is, the voltage at the positive input terminal of the comparator is less than the voltage at the negative input terminal, the comparator outputs a negative level, and when the amplitude of the secondary AC voltage of a phase corresponding to itself in the distribution network dynamic model system is negative, that is, the voltage at the positive input terminal of the comparator is greater than the voltage at the negative input terminal, the comparator outputs a positive level. When the input voltage of the comparator changes from positive to negative or from negative to positive, it is the zero-crossing point of the phase. At this time, the comparator outputs a rising edge or a falling edge. Therefore, the rising edge or falling edge signal output by the comparator at the zero-crossing point is a zero-crossing signal. Among them, Figure 2 The ZERO pin in the circuit is the output of the zero-crossing detection circuit. When the output is rising, the phase is 180°, and when the output is falling, the phase is 0°.

[0109] The comparator can be connected to the processor through a GPIO pin with a hardware interrupt function on the processor, thereby sending the zero-crossing signal of the faulty phase to the processor, so that the processor determines that the faulty phase has crossed the zero point when receiving the zero-crossing signal, so as to perform subsequent control.

[0110] The zero-crossing detection circuit in this embodiment can not only realize the detection of the zero-crossing point, but also avoid the problems of the conventional use of optocouplers as zero-crossing detection, such as the input resistor becoming hot, the inability to distinguish between 0° and 180°, and the inaccurate zero-crossing pulse.

[0111] As a preferred embodiment, after receiving the zero-crossing signals sent by each zero-crossing detection circuit to perform real-time zero-crossing detection on each phase AC voltage of the power distribution network dynamic model system, it also includes:

[0112] Determine whether the time difference between the time when the zero-crossing signal is received this time and the time when the zero-crossing signal is received last time is within a preset range;

[0113] If so, the step of determining the fault triggering time based on the zero-crossing point detection and the fault initial phase angle of the fault phase of the dynamic model system of the distribution network set by the user is entered.

[0114] The applicant has taken into consideration that when harmonics are present, the zero-crossing detection circuit may be affected by the harmonics and malfunction. If the processor performs control based on the zero-crossing signal sent by the zero-crossing detection circuit when it malfunctions, it may cause the faulty phase to be single-phase grounded at a time when the user does not expect a single-phase fault simulation.

[0115] In order to solve the above technical problems, in the present application, in order to control based on the correct zero-crossing signal, when receiving the zero-crossing signal, first determine whether the time difference between the time when the zero-crossing signal is received this time and the time when the zero-crossing signal is received last time is within a preset range, such as 10ms±△t, △t can be 0.5ms. If it is within the range, it can be determined that the zero-crossing signal received this time is valid, and control can be performed by the zero-crossing signal received this time. However, if the time difference exceeds the preset range, such as too large or too small, it can be determined that the zero-crossing signal is generated due to interference or harmonics, and no control is performed at this time to avoid safety problems for staff caused by mis-control of the fault phase grounding.

[0116] As a preferred embodiment, the control end of each bidirectional thyristor module is respectively connected to a thyristor trigger circuit;

[0117] Controlling the conduction of the bidirectional thyristor module connected to the fault, including:

[0118] Output PWM (Pulse width modulation) flag enable signal, and control the control end of the thyristor trigger circuit corresponding to the bidirectional thyristor module connected to the fault to enable, and output PWM waveform through the control end of the thyristor trigger circuit, so that the thyristor trigger circuit drives the bidirectional thyristor module connected to the fault to conduct;

[0119] After the fault duration set by the user, the bidirectional thyristor module is controlled to shut down, including:

[0120] Stop outputting the PWM flag enable signal, and stop controlling the control end enable of the thyristor trigger circuit corresponding to the bidirectional thyristor module connected to the fault, so that the thyristor trigger circuit drives the bidirectional thyristor module connected to the fault to turn off.

[0121] In this embodiment, when controlling the bidirectional thyristor module to turn on, it is achieved by outputting a PWM flag enable signal and controlling the control end of the corresponding thyristor trigger circuit to enable. Specifically, Figure 3 As shown, Figure 3 A schematic diagram of the structure of a thyristor trigger circuit provided by the present invention, Figure 3 The TRIG pin in the thyristor trigger circuit is the control terminal. Figure 3 When the TRIG pin in is enabled, a PWM waveform will be output through TRIG to control the on and off of the switch tube in the thyristor trigger circuit. Based on this, the bidirectional thyristor module connected to the fault phase can be controlled to be turned on to ground the fault phase.

[0122] When the thyristor trigger circuit controls the conduction of the bidirectional thyristor module, it outputs a trigger voltage of about 2.5V and a trigger current of about 100mA through the output end to trigger the thyristor to conduct. The circuit adopts pulse transformer isolation control, with strong driving ability and high voltage resistance. The processor outputs PWM waveform through TRIG, which is output to the transformer through the primary drive of Q18 or Q2, the secondary drive of Q8, Q13, Q1, Q3, and the transformer output is rectified by the rectifier module and connected to the control end of the bidirectional thyristor module.

[0123] In addition, after the fault duration has passed, the bidirectional thyristor module needs to be controlled to disconnect to disconnect the grounding of the faulty phase. At this time, this can be achieved by stopping the output of the PWM flag enable signal and stopping the control of the TRIG pin enable.

[0124] Based on this, the PWM waveform is output through the control end of the thyristor trigger circuit to control the switch tube in the thyristor trigger circuit, so as to realize the control of the bidirectional thyristor module with the effect of simple operation and easy adjustment.

[0125] As a preferred embodiment, the power distribution network dynamic model system further includes a current detection device for detecting a loop current in the power distribution network dynamic model system;

[0126] The method also includes:

[0127] If it is detected that the loop current in the dynamic mode system of the distribution network is greater than the overcurrent protection current, each bidirectional thyristor module is controlled to be turned off.

[0128] In order to avoid a large loop current when multiple phases in the distribution network dynamic model system are short-circuited at the same time, and the large short-circuit current causes the failure of the bidirectional thyristor module, a current detection circuit is also provided in this embodiment. The loop current in the distribution network dynamic model system is detected by the current detection circuit, so as to control each bidirectional thyristor module to be shut down when it is detected that the loop current is greater than the overcurrent protection current, so as to ensure the normal operation of the bidirectional thyristor module.

[0129] As a preferred embodiment, the bidirectional thyristor module includes a positive half-cycle conducting thyristor and a negative half-cycle conducting thyristor;

[0130] The first end of the positive half-cycle conducting thyristor is connected to the second end of the negative half-cycle conducting thyristor, and is connected to the corresponding one-phase output end of the power distribution network dynamic model system; the second end of the positive half-cycle conducting thyristor is connected to the first end of the negative half-cycle conducting thyristor, and is connected to the ground end;

[0131] Controlling the conduction of the bidirectional thyristor module connected to the fault, including:

[0132] The bidirectional thyristor module connected to the fault phase is controlled to be turned on, so that when the AC voltage of the fault phase is in the positive half cycle, the fault phase is grounded by turning on the thyristor in the positive half cycle, and when the AC voltage of the fault phase is in the negative half cycle, the fault phase is grounded by turning on the thyristor in the negative half cycle.

[0133] In this embodiment, the bidirectional thyristor module includes two thyristors, namely a positive half-cycle conduction thyristor and a negative half-cycle conduction thyristor. Since the distribution network dynamic model system outputs alternating current, thyristors need to be set in both directions to ensure that the fault phase can be grounded regardless of whether the alternating current output by the distribution network dynamic model system is in the positive half cycle or the negative half cycle.

[0134] As a preferred embodiment, the fault triggering time is determined based on the zero-crossing point detection and the fault occurrence initial phase angle of the fault phase of the dynamic model system of the distribution network set by the user, including:

[0135] The fault triggering time is determined by the time calculation formula based on the zero-crossing detection and the fault initial phase angle of the fault phase of the distribution network dynamic model system set by the user;

[0136] The time calculation formula is:

[0137]

[0138] Where T is the fault trigger time, is the initial phase angle of the fault;

[0139] The fault triggering time is the time from detecting the zero crossing point to controlling the bidirectional thyristor module connected to the fault to turn on.

[0140] When calculating the fault trigger time, is the initial phase angle of the fault, the unit is 0.1°, the unit of the fault trigger time T is us, since the frequency of the AC power output by the dynamic model system of the distribution network is 50Hz, the unit is s, therefore, this application is based on the formula The calculation result is relatively accurate and can be controlled according to the user's settings.

[0141] Please refer to Figure 4 , Figure 4 The present invention provides a structural schematic diagram of a phase-controlled switch design system for a dynamic mold system, which is applied to a dynamic mold system for a distribution network. A bidirectional thyristor module is provided between each phase output terminal and a ground terminal of the dynamic mold system for the distribution network. The phase-controlled switch design system for the dynamic mold system includes:

[0142] The detection unit 41 is used to perform real-time zero-crossing detection on each phase AC voltage of the dynamic model system of the power distribution network;

[0143] A determination unit 42, configured to determine a fault trigger time based on zero-crossing point detection and a fault occurrence initial phase angle of a fault phase of a dynamic model system of a power distribution network set by a user;

[0144] A judging unit 43, used to judge whether a start signal is received;

[0145] The first control unit 44 is used to control the bidirectional thyristor module connected to the fault phase to conduct after receiving the start signal and detecting that the AC voltage of the fault phase passes through the zero point and the fault trigger time has passed, so as to ground the fault phase;

[0146] The second control unit 45 is used to control the bidirectional thyristor module to turn off after a fault duration set by the user has elapsed.

[0147] For an introduction to a phase-controlled switch design system for a moving mold system provided by the present invention, please refer to the above method embodiment, and the present invention will not be described in detail here.

[0148] Please refer to Figure 5 , Figure 5 The present invention provides a schematic structural diagram of a phase-controlled switch design device for a moving mold system, the device comprising:

[0149] A memory 51, used for storing computer programs;

[0150] The processor 52 is used to implement the steps of the phase-controlled switch design method of the dynamic mold system as described above when executing the computer program.

[0151] For an introduction to a phase-controlled switch design device for a moving mold system provided by the present invention, please refer to the above method embodiment, and the present invention will not be repeated here.

[0152] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0153] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A phase-controlled switch design method for a moving mold system, characterized in that: Applied to a power distribution network dynamic model system, a bidirectional thyristor module is provided between each phase output terminal and a ground terminal of the power distribution network dynamic model system, and the method comprises: Performing real-time zero-crossing detection on each phase of the AC voltage of the power distribution network dynamic model system; Determine the fault trigger time based on the zero-crossing point detection and the fault occurrence initial phase angle of the fault phase of the dynamic model system of the power distribution network set by the user; Determine whether a start signal is received; If yes, when the fault trigger time has passed after the AC voltage of the fault phase passes through the zero point, the bidirectional thyristor module connected to the fault phase is controlled to be turned on so that the fault phase is grounded; After a fault duration set by a user has elapsed, controlling the bidirectional thyristor module to turn off; Each phase of the power distribution network dynamic model system is respectively provided with a zero-crossing detection circuit for real-time detection of the zero-crossing point of the corresponding one-phase AC voltage in the power distribution network dynamic model system, and sending a zero-crossing signal when the zero-crossing point is detected; Performing real-time zero-crossing detection on each phase AC voltage of the power distribution network dynamic model system includes: Receiving the zero-crossing signal sent by each of the zero-crossing detection circuits to perform real-time zero-crossing detection on each phase of the AC voltage of the power distribution network dynamic model system; The zero-crossing detection circuit comprises a comparator, wherein the positive input terminal of the comparator is grounded, and the negative input terminal is connected to the secondary AC voltage of one phase corresponding to itself in the dynamic model system of the distribution network, and is used for outputting a negative level when the amplitude of the secondary AC voltage of one phase corresponding to itself in the dynamic model system of the distribution network is positive, and outputting a positive level when the amplitude of the secondary AC voltage of one phase corresponding to itself in the dynamic model system of the distribution network is negative, and outputting a rising edge signal or a falling edge signal when the secondary AC voltage of one phase corresponding to itself in the dynamic model system of the distribution network passes through a zero point, and the rising edge signal or the falling edge signal is the zero-crossing signal; After receiving the zero-crossing signal sent by each of the zero-crossing detection circuits to perform real-time zero-crossing detection on each phase AC voltage of the power distribution network dynamic model system, the method further includes: Determine whether the time difference between the time when the zero-crossing signal is received this time and the time when the zero-crossing signal was received last time is within a preset range; If so, the step of determining the fault trigger time based on the zero-crossing point detection and the fault initial phase angle of the fault phase of the dynamic model system of the distribution network set by the user is entered.

2. The phase-controlled switch design method of the dynamic mold system according to claim 1, characterized in that: Before determining the fault trigger time based on the zero-crossing point detection and the fault occurrence initial phase angle of the fault phase of the dynamic model system of the power distribution network set by the user, the method further includes: Receive the fault phase setting of the power distribution network dynamic model system, the fault initial phase angle setting of the fault phase and the fault duration setting sent by the user through the human-computer interaction control device.

3. The phase-controlled switch design method of the dynamic mold system according to claim 2, characterized in that: A circuit breaker is provided between each phase output end of the power distribution network dynamic model system and the bidirectional thyristor module; The human-machine interaction control device is also used to control the closing of each of the circuit breakers before sending the fault phase setting of the distribution network dynamic model system, the initial phase angle setting of the fault phase, and the fault duration setting; and to control the opening of each of the circuit breakers when an overcurrent fault occurs in the distribution network dynamic model system.

4. The phase-controlled switch design method of the moving mold system according to claim 1, characterized in that: After determining the fault trigger time based on the zero-crossing point detection and the fault occurrence initial phase angle of the fault phase of the dynamic model system of the power distribution network set by the user, the method further includes: Set the timing time of the timer to the fault trigger time; When the fault trigger time has passed after the AC voltage of the fault phase passes through a zero point, controlling the bidirectional thyristor module connected to the fault phase to be turned on so that the fault phase is grounded, including: When the AC voltage of the fault phase passes through a zero point, the timer is controlled to be enabled so that the timer starts timing; After receiving the timing end signal sent by the timer, the bidirectional thyristor module connected to the fault phase is controlled to be turned on, so that the fault phase is grounded.

5. The phase-controlled switch design method of the moving mold system according to claim 1, characterized in that: The control end of each bidirectional thyristor module is respectively connected to a thyristor trigger circuit; Controlling the bidirectional thyristor module connected to the fault to be turned on, comprising: Outputting a PWM flag enable signal, and controlling the control end of the thyristor trigger circuit corresponding to the bidirectional thyristor module connected to the fault to be enabled, and outputting a PWM waveform through the control end of the thyristor trigger circuit, so that the thyristor trigger circuit drives the bidirectional thyristor module connected to the fault to be turned on; After a fault duration set by a user has elapsed, the bidirectional thyristor module is controlled to be turned off, comprising: Stop outputting the PWM flag enable signal, and stop controlling the control end enable of the thyristor trigger circuit corresponding to the bidirectional thyristor module connected to the fault, so that the thyristor trigger circuit drives the bidirectional thyristor module connected to the fault to turn off.

6. The phase-controlled switch design method of the moving mold system according to claim 1, characterized in that: The power distribution network dynamic model system further comprises a current detection device for detecting a loop current in the power distribution network dynamic model system; The method further comprises: If it is detected that the loop current in the dynamic mode system of the power distribution network is greater than the overcurrent protection current, each of the bidirectional thyristor modules is controlled to be turned off.

7. The phase-controlled switch design method of the moving mold system according to claim 1, characterized in that: The bidirectional thyristor module comprises a positive half-cycle conducting thyristor and a negative half-cycle conducting thyristor; The first end of the positive half-cycle conducting thyristor is connected to the second end of the negative half-cycle conducting thyristor, and is connected to the corresponding one-phase output end of the power distribution network dynamic model system; the second end of the positive half-cycle conducting thyristor is connected to the first end of the negative half-cycle conducting thyristor, and is connected to the ground end; Controlling the bidirectional thyristor module connected to the fault to be turned on, comprising: The bidirectional thyristor module connected to the fault phase is controlled to be turned on, so that when the AC voltage of the fault phase is in a positive half cycle, the fault phase is grounded by turning on the thyristor in the positive half cycle, and when the AC voltage of the fault phase is in a negative half cycle, the fault phase is grounded by turning on the thyristor in the negative half cycle.

8. The phase-controlled switch design method of the moving mold system according to claim 1, characterized in that: Determining the fault trigger time based on the zero-crossing point detection and the fault occurrence initial phase angle of the fault phase of the dynamic model system of the power distribution network set by the user includes: Determine the fault trigger time through a time calculation formula based on the zero-crossing point detection and the fault initial phase angle of the fault phase of the dynamic model system of the power distribution network set by the user; The time calculation formula is: Wherein, T is the fault triggering time, An initial phase angle for the fault; The fault triggering time is the time from detecting the zero crossing point to controlling the bidirectional thyristor module connected to the fault to be turned on.

9. A phase-controlled switch design system for a dynamic mold system, characterized in that: Applied to the dynamic model system of the power distribution network, a bidirectional thyristor module is respectively arranged between each phase output terminal and the ground terminal of the dynamic model system of the power distribution network, and the phase-controlled switch design system of the dynamic model system includes: A detection unit, used for performing real-time zero-crossing detection on each phase AC voltage of the power distribution network dynamic model system; A determination unit, configured to determine a fault trigger time based on the zero-crossing point detection and a fault occurrence initial phase angle of a fault phase of the dynamic model system of the power distribution network set by a user; A judging unit, used to judge whether a start signal is received; A first control unit is used for controlling the bidirectional thyristor module connected to the fault phase to be turned on after receiving a start signal and detecting that the AC voltage of the fault phase passes through a zero point and the fault trigger time has passed, so as to ground the fault phase; A second control unit, used to control the bidirectional thyristor module to turn off after a fault duration set by a user has elapsed; Each phase of the power distribution network dynamic model system is respectively provided with a zero-crossing detection circuit for real-time detection of the zero-crossing point of the corresponding one-phase AC voltage in the power distribution network dynamic model system, and sending a zero-crossing signal when the zero-crossing point is detected; The detection unit is specifically used for: Receiving the zero-crossing signal sent by each of the zero-crossing detection circuits to perform real-time zero-crossing detection on each phase of the AC voltage of the power distribution network dynamic model system; The zero-crossing detection circuit comprises a comparator, wherein the positive input terminal of the comparator is grounded, and the negative input terminal is connected to the secondary AC voltage of one phase corresponding to itself in the dynamic model system of the distribution network, and is used for outputting a negative level when the amplitude of the secondary AC voltage of one phase corresponding to itself in the dynamic model system of the distribution network is positive, and outputting a positive level when the amplitude of the secondary AC voltage of one phase corresponding to itself in the dynamic model system of the distribution network is negative, and outputting a rising edge signal or a falling edge signal when the secondary AC voltage of one phase corresponding to itself in the dynamic model system of the distribution network passes through a zero point, and the rising edge signal or the falling edge signal is the zero-crossing signal; The phase-controlled switch design system of the moving mold system is also used for: Determine whether the time difference between the time when the zero-crossing signal is received this time and the time when the zero-crossing signal was received last time is within a preset range; If so, the step of determining the fault trigger time based on the zero-crossing point detection and the fault initial phase angle of the fault phase of the dynamic model system of the distribution network set by the user is entered.

10. A phase-controlled switch design device for a moving mold system, characterized in that: include: Memory for storing computer programs; A processor, used to implement the steps of the phase-controlled switch design method of the dynamic mold system as claimed in any one of claims 1 to 8 when executing the computer program.

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