Gate drive circuit of thyristor device, control method and power electronic device
By introducing pre-turn-off and hard-drive turn-off stages into the gate drive circuit of thyristor-type devices, the carrier concentration can be dynamically adjusted, solving the problem that the loss characteristics of thyristor-type devices cannot be flexibly adjusted, and achieving loss optimization and device reliability improvement under different operating conditions.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-27
- Publication Date
- 2026-04-14
AI Technical Summary
In the prior art, the trade-off relationship between the on-state loss and the off-state loss of thyristor devices is fixed and cannot be flexibly adjusted under the dynamic changing operating conditions of power electronic systems, resulting in additional losses.
The gate drive circuit using thyristor-type devices generates a pre-turn-off voltage during the pre-turn-off phase and maintains it for a certain duration, then switches to a hard-drive turn-off voltage to dynamically adjust the carrier concentration and optimize loss characteristics.
It enables dynamic adjustment of the loss characteristics of thyristor devices under different operating conditions, reduces turn-off loss, improves the robustness and reliability of the devices, and suppresses the dynamic avalanche effect.
Smart Images
Figure CN121864074A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of semiconductor device technology, and in particular to a gate drive circuit, control method and power electronic device for thyristor-type devices. Background Technology
[0002] Currently, typical applications of high-power semiconductor devices include medium-voltage motor drives (MVD), wind turbine converters, modular multilevel converters (MMC) in high-voltage direct current (HVDC) systems, electric traction systems, solid-state circuit breakers (SSB), and static synchronous compensators (STATCOM). Thyristor devices, with their low on-state losses and high reliability, are the preferred semiconductor devices for these applications. Thyristor devices can include IGCT (Integrated Gate Commutated Thyristor), GTO (Gate Turn-Off Thyristor), ETO (Emitter Turn-Off Thyristor), and other types of non-gate cathode short-circuit thyristors.
[0003] Taking the IGCT (Inductively Coupled Transistor) as an example, during conduction, the four-layer pnpn structure enters a latching state, generating a strong conductivity modulation effect. In this state, a large number of electrons and holes are injected into the base region of the device, forming a high-density plasma, resulting in extremely low on-resistance and on-state voltage drop (Von) during conduction. During turn-off, the gate drive unit of the IGCT needs to provide a high-amplitude negative voltage to commutate all the cathode current to the gate in a very short time, causing the pnpn structure to lose its latching condition and switch to pnp transistor mode, ultimately causing the main current to drop rapidly to zero. Because the carrier concentration in the base region of the IGCT is extremely high during conduction, a large amount of stored charge needs to be "extracted" from the base region during turn-off, resulting in a long current tail during turn-off and a high instantaneous power consumption peak in the overlapping region of voltage rise and current fall, thus generating a large turn-off loss (Eoff).
[0004] There is a trade-off between the on-state loss and turn-off loss of the aforementioned thyristor devices. From a device physics perspective, reducing the on-state voltage drop requires increasing carrier injection during the on-state, thereby enhancing the conductance modulation effect. However, more carrier injection means that more stored charge needs to be cleared during turn-off, thus increasing turn-off loss. Conversely, reducing turn-off loss requires reducing the amount of charge cleared during turn-off, which typically means a lower carrier concentration during the on-state, leading to a higher on-state voltage drop and increased on-state loss.
[0005] In related technologies, to optimize the trade-off between on-state and off-state losses in thyristor-type devices, the carrier lifetime within the device is typically shortened during semiconductor device manufacturing. This reduces the total amount of charge that needs to be swept away during off-state, thus reducing off-state losses. However, this also leads to a corresponding decrease in carrier concentration during the on-state, resulting in increased on-state voltage drop (Von) and increased on-state losses. This approach is usually used to customize semiconductor devices with loss characteristics that meet product requirements. Another approach is to reduce the thickness of the semiconductor device or improve carrier extraction efficiency, thereby reducing both on-state and off-state losses.
[0006] However, the aforementioned solutions all involve improvements to the manufacturing process and structure of thyristor devices, and are therefore static optimizations. Once a thyristor device is manufactured, the trade-off between its on-state loss and turn-off loss is permanently fixed and cannot be changed or adjusted. This contradicts the dynamically changing operating conditions of power electronic systems, leading to unnecessary additional losses due to the fixed loss characteristics when operating conditions change. Therefore, how to flexibly adjust on-state and turn-off losses based on the dynamically changing operating conditions of power electronic systems, and improve the flexibility and adaptability of optimization methods, has become an urgent technical problem to be solved. Summary of the Invention
[0007] This application provides a gate drive circuit, control method, and power electronic device for thyristor-type devices, which can improve the technical problem that the loss characteristics of thyristor-type devices cannot be adjusted according to the actual working environment in related technologies.
[0008] In a first aspect, this application provides a gate drive circuit for a thyristor-type device, comprising: The voltage generation module has its control terminal connected to the communication interface. The voltage generation module is used to generate a pre-shutdown voltage or a hard-drive shutdown voltage based on the received shutdown command. The switching module has its first terminal connected to the voltage generation module, its second terminal connected to the gate of a thyristor-type device, and its control terminal connected to the communication interface. The switching module is used to turn on based on a received turn-off command. During the pre-shutdown phase, the voltage generation module generates a pre-shutdown voltage in response to the shutdown command and maintains the pre-shutdown duration, while the switching module turns on in response to the shutdown command. During the hard-drive shutdown phase, the voltage generation module switches the pre-shutdown voltage to the hard-drive shutdown voltage, while the switching module remains on.
[0009] Optionally, the voltage generation module includes: Voltage regulator; A microcontroller, connected to the control terminal of a voltage regulator, is used to control the voltage regulator to generate a pre-shutdown voltage in response to a shutdown command during the pre-shutdown phase and to control the voltage regulator to generate a hard-drive shutdown voltage during the hard-drive shutdown phase.
[0010] Optionally, the shutdown instruction may also include a pre-shutdown duration; the microcontroller is further configured to determine the pre-shutdown duration of the pre-shutdown phase based on the received shutdown instruction.
[0011] Optionally, the microcontroller is also used to receive monitoring parameters during the operation of the thyristor-type device, and to determine the voltage amplitude of the pre-turn-off voltage and / or the pre-turn-off duration of the pre-turn-off phase based on the monitoring parameters.
[0012] Optionally, the switch module includes: The first switching device is connected between the voltage generation module and the gate of the thyristor-type device; the voltage generation module, the first switching device, and the gate of the thyristor-type device are used to form a hard-drive turn-off branch. An impedance element and a second switching device are connected in series between the voltage generation module and the gate of the thyristor-like device; the voltage generation module, the impedance element, the second switching device, and the gate of the thyristor-like device are used to form a pre-turn-off branch.
[0013] Optionally, the impedance element includes a resistive device or an inductive device.
[0014] Optionally, the gate drive circuit for thyristor-type devices further includes: The current generation module is connected to the gate of the thyristor-like device. The current generation module is used to provide a pre-turn-off current to the gate of the thyristor-like device during the pre-turn-off phase, so as to extract a portion of the charge carriers from the thyristor-like device while keeping it in the on state.
[0015] Optionally, the voltage generation module includes a voltage regulator and a microcontroller, the microcontroller also being used to adjust the pre-shutdown current based on monitoring parameters during the operation of the thyristor-type device.
[0016] Secondly, this application provides a control method for thyristor-type devices, applied to the gate drive circuit of the thyristor-type device of the first aspect, the method comprising: When the thyristor-type device is in the on state, in response to the turn-off command sent by the main control unit, a pre-turn-off voltage is applied to the gate of the thyristor-type device. When the duration of the applied pre-turn-off voltage reaches the pre-turn-off duration, a hard-drive turn-off voltage is applied to the gate of the thyristor-type device.
[0017] Optionally, if the duration of applying the pre-turn-off voltage reaches the pre-turn-off duration, before applying the hard-drive turn-off voltage to the gate of the thyristor-type device, the following steps are also included: Receive monitoring parameters of thyristor devices during operation via the communication interface; The voltage amplitude of the pre-shutdown voltage is determined based on the monitoring parameters, and / or the pre-shutdown duration of the pre-shutdown phase.
[0018] Optionally, in response to a turn-off command sent by the main control unit, a pre-turn-off voltage is applied to the gate of the thyristor-type device, including: In response to the shutdown command sent by the main control unit, the control voltage generation module generates a pre-shutdown voltage and controls the switch module to turn on. Applying a hard-drive turn-off voltage to the gate of a thyristor-type device, including; The control voltage generation module generates the hard drive shutdown voltage and the control switch module maintains the on state.
[0019] Optionally, in response to a turn-off command sent by the main control unit, a pre-turn-off voltage is applied to the gate of the thyristor-type device, including: In response to the shutdown command sent by the main control unit, the control voltage generation module generates a preset voltage and controls the first switching device to open and the second switching device to open. Applying a hard-drive turn-off voltage to the gate of a thyristor-type device, including; The control voltage generation module generates a preset voltage, controls the first switching device to turn on, and the second switching device to turn off.
[0020] Thirdly, this application provides a power electronic device, including a thyristor-type device and a gate drive circuit for the thyristor-type device of the first aspect.
[0021] The gate drive circuit, control method, and power electronic device of the thyristor-like device disclosed in this application, by setting a voltage generation module and a switching module, allows the voltage generation module to generate a pre-turn-off voltage and maintain the pre-turn-off duration during the pre-turn-off phase. The switching module can provide the pre-turn-off voltage to the gate of the thyristor-like device to reduce the carrier concentration of the device in advance during the pre-turn-off phase. During the hard-drive turn-off phase, the voltage generation module can generate a hard-drive turn-off voltage, thereby achieving the turn-off of the thyristor-like device. Because the carrier concentration of the device is reduced during the pre-turn-off phase, the total charge required for commutation during the hard-drive turn-off phase is reduced, the turn-off current decreases faster, and the tail current is smaller, thus effectively reducing the turn-off loss. Furthermore, according to the actual operating conditions of the thyristor-like device, the pre-turn-off duration and pre-turn-off voltage can be adjusted to balance the on-state loss and turn-off loss, thereby achieving dynamic adjustment of the loss characteristics of the thyristor-like device under different operating conditions. Attached Figure Description
[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0023] Figure 1 This is a schematic diagram showing the correspondence between the on-state voltage drop (Von) and the turn-off loss (Eoff) of different IGCTs in related technologies; Figure 2 This is a schematic diagram of the gate drive circuit of a thyristor-type device provided in an embodiment of this application; Figure 3 This is a schematic diagram showing the gate voltage of a pre-shutdown IGCT and a conventional IGCT over time, provided in an embodiment of this application. Figure 4 This is a schematic diagram showing the actual current and anode-cathode voltage difference of a pre-shutdown IGCT and a conventional IGCT over time, provided in an embodiment of this application.
[0024] Figure 5 This is a schematic diagram of the gate drive circuit of a thyristor-type device provided in another embodiment of this application; Figure 6 This is a schematic diagram of the gate drive circuit of a thyristor-type device provided in another embodiment of this application; Figure 7 This is a schematic flowchart of a control method for a thyristor-type device provided in an embodiment of this application; In the attached image: 10. Voltage generation module; 20. Communication interface; 30. Switching module; 40. Thyristor devices; 11. Voltage regulator; 12. Microcontroller; 31. First switching device; 32. Second switching device; 33. Impedance element. Detailed Implementation
[0025] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.
[0026] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.
[0027] Currently, typical applications of high-power semiconductor devices include medium-voltage motor drives (MVD), wind turbine converters, modular multilevel converters (MMC) in high-voltage direct current (HVDC) systems, electric traction systems, solid-state circuit breakers (SSB), and static synchronous compensators (STATCOM). Thyristor devices, with their low on-state losses and high reliability, are the preferred semiconductor devices for these applications. Thyristor devices can include IGCT (Integrated Gate Commutated Thyristor), GTO (Gate Turn-Off Thyristor), ETO (Emitter Turn-Off Thyristor), and other types of non-gate cathode short-circuit thyristors.
[0028] Taking the IGCT (Inductively Coupled Transistor) as an example, during conduction, the four-layer pnpn structure enters a latching state, generating a strong conductivity modulation effect. In this state, a large number of electrons and holes are injected into the base region of the device, forming a high-density plasma, resulting in extremely low on-resistance and on-state voltage drop (Von) during conduction. During turn-off, the gate drive unit of the IGCT needs to provide a high-amplitude negative voltage to commutate all the cathode current to the gate in a very short time, causing the pnpn structure to lose its latching condition and switch to pnp transistor mode, ultimately causing the main current to drop rapidly to zero. Because the carrier concentration in the base region of the IGCT is extremely high during conduction, a large amount of stored charge needs to be "extracted" from the base region during turn-off, resulting in a long current tail during turn-off and a high instantaneous power consumption peak in the overlapping region of voltage rise and current fall, thus generating a large turn-off loss (Eoff).
[0029] There is a trade-off between the on-state loss and turn-off loss of the aforementioned thyristor devices. From a device physics perspective, reducing the on-state voltage drop requires increasing carrier injection during the on-state, thereby enhancing the conductance modulation effect. However, more carrier injection means that more stored charge needs to be cleared during turn-off, thus increasing turn-off loss. Conversely, reducing turn-off loss requires reducing the amount of charge cleared during turn-off, which typically means a lower carrier concentration during the on-state, leading to a higher on-state voltage drop and increased on-state loss.
[0030] In related technologies, to optimize the trade-off between on-state and off-state losses in thyristor-type devices, the carrier lifetime within the device is typically shortened during semiconductor device manufacturing. This reduces the total amount of charge that needs to be swept away during off-state, thus reducing off-state losses. However, this also leads to a corresponding decrease in carrier concentration during the on-state, resulting in increased on-state voltage drop (Von) and increased on-state losses. This approach is usually used to customize semiconductor devices with loss characteristics that meet product requirements. Another approach is to reduce the thickness of the semiconductor device or improve carrier extraction efficiency, thereby reducing both on-state and off-state losses.
[0031] However, the above solutions all involve improvements to the manufacturing process and structure of thyristor devices, and are therefore static optimizations. Once a thyristor device is manufactured, the trade-off between its on-state loss and turn-off loss is permanently fixed and cannot be changed or adjusted. Taking the IGCT (Inductively Coupled Transistor) as an example... Figure 1 The trade-off relationship between on-state voltage drop (Von) and turn-off loss (Eoff) for different IGCTs is shown. Figure 1 As shown, IGCTs can be categorized into high-power technology (HPT-technology) and standard technology. For each IGCT, there is a negative correlation between its on-state voltage drop and turn-off loss; the larger the on-state voltage drop, the smaller the turn-off loss. Therefore, under high-frequency, low-current conditions, IGCTs with large on-state voltage drops and low turn-off losses can be selected, while under low-frequency, high-current conditions, IGCTs with small on-state voltage drops and high turn-off losses can be selected. However, the actual operating conditions of power electronic systems are dynamically changing. When operating conditions change, devices, due to their fixed loss characteristics, will generate unnecessary additional losses. Therefore, how to flexibly adjust on-state and turn-off losses based on the dynamically changing operating conditions of power electronic systems, and improve the flexibility and adaptability of optimization methods, has become an urgent technical problem to be solved.
[0032] To address at least one of the aforementioned technical problems, embodiments of this application provide a gate drive circuit, control method, and power electronic device for thyristor-type devices. The gate drive circuit for thyristor-type devices provided in this application embodiment will be described below first.
[0033] like Figure 2 As shown, the gate drive circuit of a thyristor-type device may include a voltage generation module 10 and a switching module 30.
[0034] The control terminal of the voltage generation module 10 can be connected to the communication interface 20. The main control unit of the device (not shown) can send corresponding control commands, such as turn-on commands and turn-off commands, to the voltage generation module 10 through the communication interface 20. When the voltage generation module 10 receives a turn-off command, it can generate a pre-turn-off voltage or a hard-drive turn-off voltage. The communication interface 20 can be a fiber optic interface or other types of communication interfaces, which are not limited here.
[0035] The first terminal of the switching module 30 can be connected to the voltage generation module 10, and the second terminal of the switching module 30 can be connected to the gate of the thyristor-like device 40. The control terminal of the switching module 30 can be connected to the communication interface 20 to receive control commands sent by the main control unit. When the switching module 30 receives a turn-off command, it can switch to the on state.
[0036] The thyristor device 40 can be divided into three stages during operation: the conduction stage, the pre-turn-off stage, and the hard-drive turn-off stage.
[0037] During the conduction phase, the voltage generation module 10 and the switching module 30 can provide a large peak value and narrow pulse forward trigger current to the thyristor-like device 40 in the initial stage of conduction, so that the thyristor-like device 40 enters the conduction state. In the conduction state, the voltage generation module 10 and the switching module 30 can switch to providing a weak back-porch current to maintain the pnpn structure of the thyristor-like device 40 in the latched conduction state. At this time, the device is filled with a high concentration of electron-hole plasma, exhibiting an extremely low on-state voltage drop and generating a small on-state loss.
[0038] During the pre-shutdown phase, the main control unit can send a shutdown command through the communication interface 20. The voltage generation module 10 can generate a pre-shutdown voltage based on the shutdown command, and the switching module 30 can turn on based on the shutdown command to provide the pre-shutdown voltage to the gate of the thyristor-type device 40. The voltage generation module 10 can maintain the pre-shutdown voltage for the pre-shutdown duration.
[0039] During this pre-turn-off period, the gate voltage of the thyristor-like device 40 is maintained at a weak negative bias value due to the lower pre-turn-off voltage. This weak negative bias weakens the conduction of the pn junction between the gate and cathode of the thyristor-like device 40, reducing the electron injection efficiency from the cathode. At the same time, this negative bias also enhances the gate's ability to extract holes from the p-base region.
[0040] As the carrier injection rate is suppressed while internal recombination and extraction processes continue, the plasma concentration in the n-base region begins to decrease slowly. With the decrease in plasma concentration, the on-state resistance of the device increases slightly, leading to a slight increase in the on-state voltage drop (Von), but the main current still flows steadily. That is, during the pre-turn-off phase, the carrier concentration decreases slightly and the on-state voltage drop of the device increases slightly.
[0041] During the hard-drive turn-off phase, the carrier concentration inside the thyristor device 40 decreases during the pre-turn-off duration maintained by the pre-turn-off voltage. At this time, the voltage generation module 10 can switch the pre-turn-off voltage to the hard-drive turn-off voltage, while the switching module 30 remains on, applying the hard-drive turn-off voltage to the gate of the thyristor device 40. That is, the gate drive circuit applies a large-amplitude negative bias voltage and provides a high di / dt negative gate current pulse during the hard-drive turn-off phase. During the hard-drive turn-off phase, the cathode current of the thyristor device 40 is rapidly commutated to the gate, causing the pnpn structure of the thyristor device 40 to lose its latching condition and quickly switch to pnp transistor mode, thus turning off the thyristor device 40.
[0042] As an example, the negative voltage amplitude of the hard-drive turn-off phase can be set to be greater than that of the pre-turn-off phase. For example, the negative bias value (VG, pre) of the pre-turn-off voltage with a smaller negative voltage amplitude in the pre-turn-off phase can be -1V to -5V; the negative bias value of the hard-drive turn-off voltage with a larger negative voltage amplitude in the hard-drive turn-off phase is approximately -20V.
[0043] As another example, the pre-turn-off phase and the hard-drive turn-off phase can also use the same voltage amplitude, with the magnitude of the pre-turn-off current and the hard-drive turn-off current limited by impedance elements in different branches.
[0044] It should be noted that the negative bias voltage with a small amplitude during the pre-turn-off phase should be greater than the gate-cathode negative breakdown voltage of thyristor-type devices.
[0045] Understandably, the aforementioned hard-drive turn-off stage, which involves a pre-turn-off phase, reduces the total charge (Qrr) required for commutation during the hard-drive turn-off phase compared to existing technologies that directly perform hard-drive turn-off. This is because the pre-turn-off phase clears some of the charge in advance, resulting in a faster drop in turn-off current, a smaller tail current, and a significantly reduced overlap area between voltage rise and current drop (i.e., turn-off loss Eoff), thus significantly reducing turn-off losses.
[0046] In the above embodiments, the pre-turn-off duration can be dynamically adjusted according to the specific application conditions of the thyristor device 40. For example, when the switching frequency of the thyristor device 40 is low and the current flowing through it in the on-state is large, the pre-turn-off duration can be reduced, or even reduced to 0. By reducing the pre-turn-off duration, the on-state loss during the pre-turn-off stage can be reduced. Since the switching frequency is low, the proportion of switching loss to the overall loss is small, and reducing the on-state loss can effectively reduce the overall loss.
[0047] When the switching frequency of the thyristor device 40 is high and the current flowing through it in the on state is small, the pre-turn-off time can be increased. During the pre-turn-off stage, the carrier concentration of the thyristor device 40 can be reduced significantly, thereby significantly reducing the turn-off loss in the hard-drive turn-off stage. Since the switching frequency is high, the switching loss accounts for a large proportion of the overall loss. By reducing the turn-off loss, the overall loss can be effectively reduced.
[0048] Understandably, the pre-turn-off voltage can be selected within a negative voltage range. Based on the specific application conditions of the thyristor device 40, adjusting the pre-turn-off voltage can also make the total charge swept out during the pre-turn-off phase vary with the pre-turn-off voltage.
[0049] As an example, by dynamically adjusting the magnitude of the pre-turn-off voltage and the duration of the pre-turn-off period, a trade-off between conduction loss and turn-off loss can be achieved based on the actual operating conditions of the thyristor device 40, thus enabling dynamic adjustment of the loss characteristics of the thyristor device 40 under different operating conditions. Specifically, setting a pre-turn-off phase will slightly increase the conduction voltage drop and conduction loss of the thyristor device during the pre-turn-off phase, but this is exchanged for a significant reduction in turn-off loss. This trade-off relationship between conduction loss and turn-off loss can be dynamically controlled by adjusting the pre-turn-off duration and pre-turn-off voltage, achieving real-time optimization and adjustment of the loss characteristic curve of the thyristor device.
[0050] In this embodiment, by setting a voltage generation module 10 and a switching module 30, the voltage generation module 10 can generate a pre-turn-off voltage and maintain the pre-turn-off duration during the pre-turn-off phase. The switching module 30 can provide the pre-turn-off voltage to the gate of the thyristor-like device 40 to reduce the carrier concentration of the device in advance during the pre-turn-off phase. During the hard-drive turn-off phase, the voltage generation module 10 can generate a hard-drive turn-off voltage, thereby turning off the thyristor-like device 40 during the hard-drive turn-off phase. Since the carrier concentration of the device is reduced during the pre-turn-off phase, the total charge that needs to be commutated during the hard-drive turn-off phase is reduced, the turn-off current decreases faster, and the tail current is smaller, thereby effectively reducing the turn-off loss. Furthermore, according to the actual operating conditions of the thyristor-like device 40, the pre-turn-off duration and pre-turn-off voltage can be adjusted to balance the on-state loss and turn-off loss, thereby achieving dynamic adjustment of the loss characteristics of the thyristor-like device 40 under different operating conditions.
[0051] It should be noted that, in addition to the dynamic adjustment of loss characteristics described in the above embodiments, the above implementation methods can also achieve the effects of suppressing dynamic avalanche and improving shutdown capability.
[0052] Specifically, suppressing dynamic avalanche refers to the phenomenon where, during the turn-off process, especially under high voltage, the rapid increase in the internal electric field of a device leads to collisional ionization of charge carriers, generating current filaments and ultimately causing device damage. The above-described implementation reduces the internal charge carrier concentration of the device in advance through a pre-turn-off phase, thus reducing the amount of charge that needs to be cleared during the hard-drive turn-off phase. This helps to alleviate the steepness of the electric field at the moment of turn-off to some extent, mitigating the dynamic avalanche effect and thereby improving the device's safety during high-voltage turn-off.
[0053] Improving turn-off capability refers to the pre-turn-off stage clearing some charge in advance, allowing the device to withstand higher current and voltage during the hard-drive turn-off stage. This expands the device's safe operating area (SOA) and enhances the robustness of thyristor devices 40 under extreme conditions. Without a pre-turn-off stage, uneven current distribution during turn-off can lead to permanent device failure. The above implementation pre-processes the carrier distribution of the thyristor device before turn-off through a pre-turn-off stage, fundamentally optimizing turn-off performance and thus suppressing turn-off failure to a certain extent, improving device reliability.
[0054] Please refer to Figure 3 Taking IGCT, a type of thyristor device, as an example, Figure 3The diagram illustrates the time-varying gate voltage of the pre-turn-off IGCT and the conventional IGCT disclosed in the above embodiments. t1 represents the turn-on stage, t2 the pre-turn-off stage, and t3 the hard-drive turn-off stage. The conventional IGCT does not have a pre-turn-off stage t2; it only provides the hard-drive turn-off voltage directly in stage t3. The pre-turn-off IGCT has a pre-turn-off stage t2, during which a small negative bias voltage is provided. This lowers the gate voltage of the pre-turn-off IGCT and sweeps out some of the charge within the device, reducing the carrier concentration and thus achieving rapid turn-off in the hard-drive turn-off stage t3, while also reducing turn-off losses.
[0055] Taking IGCT, a type of thyristor device, as an example, Figure 4 The diagram illustrates the changes in actual current and anode-cathode voltage difference over time at various stages for the pre-shutdown IGCT and conventional IGCT disclosed in the above embodiments.
[0056] During the conduction phase t1, the actual current Ia of the pre-turn-off IGCT and the conventional IGCT remains consistent with the anode-cathode voltage difference Vak. At this time, the anode-cathode voltage difference Vak of the IGCT is the on-state voltage drop Von.
[0057] During the pre-turn-off phase t2, since conventional IGCTs do not have a pre-turn-off phase t2, the actual current Ia and the anode-cathode voltage difference Vak of a conventional IGCT remain consistent with those during the conduction phase t1. However, in the pre-turn-off phase t2, the on-state voltage drop Von of the pre-turn-off IGCT increases due to the decrease in carrier concentration; that is, the anode-cathode voltage difference Vak of the pre-turn-off IGCT gradually increases during the pre-turn-off phase t2.
[0058] Understandably, during the pre-turn-off phase t2, although the anode-cathode voltage difference Vak of the pre-turn-off IGCT is increased, the actual current Ia still flows steadily, which is almost no different from that of a conventional IGCT.
[0059] During the hard-drive turn-off phase t3, the pre-turn-off IGCT, with its pre-turn-off phase t2, can reduce the carrier concentration earlier. Therefore, the actual current Ia of the pre-turn-off IGCT decreases more quickly, reaching the turn-off current. Similarly, the anode-cathode voltage difference Vak of the pre-turn-off IGCT reaches steady state faster than that of a conventional IGCT.
[0060] Please refer to Figure 5 In some embodiments, the voltage generation module 10 described above may include a voltage regulator 11 and a microcontroller 12.
[0061] The microcontroller 12 can be connected to the control terminal of the voltage regulator 11. When the microcontroller 12 receives the shutdown command sent by the main control unit through the communication interface 20, it can control the voltage regulator 11 to generate a pre-shutdown voltage in the pre-shutdown phase and control the voltage regulator 11 to generate a hard-drive shutdown voltage in the hard-drive shutdown phase.
[0062] The microcontroller 12 can also control the switching module 30 to maintain the on state during the pre-shutdown phase and the hard-drive shutdown phase.
[0063] In some embodiments, the shutdown command sent by the master control unit may also include a pre-shutdown duration. Based on this shutdown command, the microcontroller 12 can determine the pre-shutdown duration and control the voltage regulator 11 to generate a pre-shutdown voltage. When controlling the voltage regulator 11 to generate the pre-shutdown voltage, the microcontroller 12 can start timing. When the timing duration reaches the pre-shutdown duration, the microcontroller 12 can control the voltage regulator 11 to switch the pre-shutdown voltage to a hard-driven shutdown voltage.
[0064] Understandably, the microcontroller 12 can be pre-set with a default pre-shutdown duration. If the shutdown command sent by the master control unit includes a pre-shutdown duration, the timing will be based on the pre-shutdown duration in the shutdown command. If the shutdown command sent by the master control unit does not include a pre-shutdown duration, the microcontroller 12 can choose either the default pre-shutdown duration or the previously updated pre-shutdown duration.
[0065] In another optional implementation, the shutdown command sent by the master control unit may include a pre-shutdown command and a hard-drive shutdown command. When the master control unit sends a pre-shutdown command, the microcontroller 12 can control the voltage regulator 11 to generate a pre-shutdown voltage based on the pre-shutdown command. After sending the pre-shutdown command, the master control unit can start timing. When the timing duration reaches the pre-shutdown duration, the master control unit can send a hard-drive shutdown command. The microcontroller 12 can control the voltage regulator 11 to switch the pre-shutdown voltage to the hard-drive shutdown voltage based on the hard-drive shutdown command.
[0066] In some embodiments, the main control unit can monitor and collect various electrical signal parameters in the electrical circuit during the operation of the thyristor-type device 40, obtain the corresponding monitoring parameters, and transmit the monitoring parameters to the microcontroller 12 through the communication interface 20. The microcontroller 12 can determine the voltage amplitude of the pre-turn-off voltage or the pre-turn-off duration of the pre-turn-off phase based on the received monitoring parameters.
[0067] It is understood that the aforementioned monitoring parameters can be load current, device junction temperature, device switching frequency, and bus voltage in the circuit, etc. The microcontroller 12 can be pre-set with the correspondence between the monitoring parameters and the voltage amplitude or pre-turn-off duration. Based on the real-time received monitoring parameters, the microcontroller 12 can determine the current optimal pre-turn-off voltage amplitude or the pre-turn-off duration of the pre-turn-off stage, so that the current loss characteristics of the thyristor device 40 match the actual operating conditions.
[0068] It should be noted that the microcontroller 12 can adjust the voltage amplitude of the pre-turn-off voltage and the pre-turn-off duration of the pre-turn-off stage separately according to the monitoring parameters, or it can adjust both the voltage amplitude of the pre-turn-off voltage and the pre-turn-off duration of the pre-turn-off stage according to the monitoring parameters.
[0069] Please refer to Figure 6 In some embodiments, the switch module 30 may include a first switch device 31, an impedance element 33, and a second switch device 32.
[0070] The first switching device 31 can be connected between the voltage generation module 10 and the gate of the thyristor-like device 40. The voltage generation module 10, the first switching device 31, and the gate of the thyristor-like device 40 can form a hard-drive turn-off branch.
[0071] Impedance element 33 and second switching device 32 are connected in series between voltage generation module 10 and the gate of thyristor device 40. Voltage generation module 10, impedance element 33, second switching device 32 and gate of thyristor device 40 can form a pre-turn-off branch.
[0072] During the pre-shutdown phase, the first switching device 31 is turned off and the second switching device 32 is turned on. The voltage generation module 10 and the impedance element 33 can form a current source to apply a negative current to the gate of the thyristor-type device 40, thereby realizing the extraction of gate carriers.
[0073] During the hard drive turn-off phase, the first switching device 31 is turned on and the second switching device 32 is turned off. The voltage generation module 10 is directly connected to the gate of the thyristor-like device 40 through the first switching device 31. At this time, the voltage provided by the voltage generation module 10 is a negative voltage with a large amplitude, that is, the hard drive turn-off voltage, so as to realize the turn-off of the thyristor-like device 40.
[0074] In some embodiments, the impedance element 33 may include a resistive device or an inductor.
[0075] When the impedance element 33 is a resistive device, the voltage generation module 10 and the resistive device are equivalent to a stable current source, which can realize the preset current carrier extraction of the gate of the thyristor-type device 40, thereby reducing the carrier concentration of the device and realizing the pre-turn-off process.
[0076] When the impedance element 33 is an inductor, the voltage generation module 10 and the inductor can also extract carriers from the gate of the thyristor-type device 40, thereby reducing the carrier concentration of the device and realizing the pre-turn-off process.
[0077] In some embodiments, the gate drive circuit of the thyristor-like device described above may further include a current generation module (not shown). The current generation module may be connected to the gate of the thyristor-like device 40. During the pre-turn-off phase, the current generation module may provide a pre-turn-off current to the gate of the thyristor-like device 40, thereby extracting carriers from the thyristor-like device 40 while the thyristor-like device 40 remains in the on state, in order to reduce the carrier concentration of the thyristor-like device 40 during the pre-turn-off phase.
[0078] In the above embodiments, the voltage generation module 10 may include a voltage regulator 11 and a microcontroller 12. The microcontroller 12 may be electrically connected to the current generation module.
[0079] During the operation of the thyristor device 40, the microcontroller 12 can monitor the parameters of the thyristor device during operation and adjust the value of the pre-turn-off current based on the monitored parameters.
[0080] Understandably, during the pre-shutdown phase, the current generation module can maintain the pre-shutdown current at a fixed value, or the microcontroller 12 can adjust the pre-shutdown current value in real time based on the monitoring parameters; no restrictions are imposed here.
[0081] As an alternative implementation, improvements to the physical structure of the device chip can be incorporated into thyristor devices employing the aforementioned pre-turn-off stage. For example, during the chip manufacturing stage of thyristor devices, localized defect regions can be introduced into the silicon mass via electron or proton irradiation, enabling controllable carrier lifetime regulation. By precisely controlling the irradiation energy and dose, the on-state carrier concentration near the anode or in the n-base region can be locally reduced, thereby pre-reducing the total charge before device turn-off. This localized control can improve cathode emission efficiency, better match the pre-turn-off process, and achieve finer loss regulation. Furthermore, with a reduced total charge, the loss trade-off between on-state and turn-off losses can be dynamically adjusted by modifying the pre-turn-off duration of the pre-turn-off stage to suit different application conditions.
[0082] The chip physical structure of the aforementioned thyristor devices can also adopt a wave-shaped p-base region to optimize the uniformity of current distribution across the entire chip of the thyristor device during the pre-turn-off phase, avoid local current concentration at the moment of hard-drive turn-off after the pre-turn-off ends, and improve the reliability of the thyristor devices.
[0083] This application also provides a control method for thyristor-type devices. Figure 7 A flowchart illustrating a control method for a thyristor-type device according to an embodiment of this application is shown. The method may include the following steps: S110, when the thyristor-type device is in the on state, in response to the turn-off command sent by the main control unit, applies a pre-turn-off voltage to the gate of the thyristor-type device. S120 applies a hard-drive turn-off voltage to the gate of a thyristor-type device when the duration of the applied pre-turn-off voltage reaches the pre-turn-off duration.
[0084] In this embodiment, by setting a voltage generation module and a switching module, the voltage generation module can generate a pre-turn-off voltage and apply it to the gate of the thyristor-like device during the pre-turn-off phase, and maintain the pre-turn-off duration. The switching module can provide the pre-turn-off voltage to the gate of the thyristor-like device to reduce the carrier concentration of the device in advance during the pre-turn-off phase. During the hard-drive turn-off phase, the voltage generation module can generate a hard-drive turn-off voltage and apply it to the gate of the thyristor-like device, thereby achieving the turn-off of the thyristor-like device during the hard-drive turn-off phase. Since the carrier concentration of the device is reduced during the pre-turn-off phase, the total charge required for commutation during the hard-drive turn-off phase is reduced, the turn-off current decreases faster, and the tail current is smaller, thereby effectively reducing the turn-off loss. Furthermore, according to the actual operating conditions of the thyristor-like device, the pre-turn-off duration and pre-turn-off voltage can be adjusted to balance the conduction loss and turn-off loss, thereby achieving dynamic adjustment of the loss characteristics of the thyristor-like device under different operating conditions.
[0085] The specific implementation methods for each of the above steps are described below.
[0086] In S110, the gate drive circuit controls the turn-on and turn-off of thyristor-like devices. When the thyristor-like device is in the turn-on state, the gate drive circuit can receive the turn-off command sent by the main control unit through the communication interface and apply a pre-turn-off voltage to the gate of the thyristor-like device. At this time, the thyristor-like device enters the pre-turn-off stage. In the pre-turn-off stage, the pre-turn-off voltage is a negative bias voltage with a small amplitude. At this time, the bias state of the pn junction between the gate and cathode of the thyristor-like device changes from positive bias to zero bias or weak reverse bias, weakening the electron injection capability of the pn junction. The carrier injection rate of the thyristor-like device decreases, and the carriers are cleared through recombination and flow into the gate, resulting in a slow decrease in the carrier concentration inside the thyristor-like device during the pre-turn-off stage.
[0087] It should be noted that, as the carrier concentration of thyristor devices gradually decreases during the pre-turn-off phase, the conductivity modulation effect of the device weakens, resulting in a slight increase in the on-state voltage drop (Von) of thyristor devices during the pre-turn-off phase.
[0088] In S120, during the pre-turn-off phase, when the gate drive circuit applies the pre-turn-off voltage for the required duration, the gate drive voltage can adjust the gate voltage applied to the thyristor-like device to a hard-drive turn-off voltage. After the pre-turn-off phase, the carrier concentration inside the thyristor-like device decreases, reducing the total charge required for commutation during turn-off. This allows for rapid turn-off of the thyristor-like device during the hard-drive turn-off phase, and significantly reduces turn-off losses.
[0089] In some embodiments, prior to S120 above, the following may also be included: S210 receives monitoring parameters of thyristor devices during operation via a communication interface; S220, determines the voltage amplitude of the pre-shutdown voltage and / or the pre-shutdown duration of the pre-shutdown phase based on monitoring parameters.
[0090] In this embodiment, the microcontroller of the gate drive circuit can receive monitoring parameters associated with thyristor devices through a communication interface, and determine the current pre-turn-off voltage amplitude and pre-turn-off duration in real time based on the correspondence between the monitoring parameters and a pre-set value. Since both the pre-turn-off voltage amplitude and the pre-turn-off duration can be dynamically adjusted, when the actual operating conditions of the thyristor devices change, the voltage amplitude and stage duration can be adjusted to match the actual operating conditions, improving the flexibility and adaptability of the thyristor device turn-off control.
[0091] In S210, the microcontroller in the gate drive circuit can receive monitoring parameters of the thyristor-type devices during operation from the main control unit via a communication interface. These monitoring parameters can include load current, device junction temperature, device switching frequency, and bus voltage in the circuit.
[0092] In the S220, the microcontroller can be pre-set with the correspondence between monitoring parameters and voltage amplitude or pre-turn-off duration. Based on the real-time received monitoring parameters, the microcontroller can determine the current optimal pre-turn-off voltage amplitude or pre-turn-off duration of the pre-turn-off stage, so that the current loss characteristics of thyristor devices match the actual operating conditions.
[0093] In some embodiments, applying a pre-turn-off voltage to the gate of a thyristor-type device in response to a turn-off command sent by the main control unit may include: In response to the shutdown command sent by the main control unit, the control voltage generation module generates a pre-shutdown voltage and controls the switch module to turn on. The above-mentioned application of a hard-drive turn-off voltage to the gate of a thyristor-type device may include: The control voltage generation module generates the hard drive shutdown voltage and the control switch module maintains the on state.
[0094] In this embodiment, the voltage generation module can be a programmable voltage source, including a microcontroller and a voltage regulator.
[0095] During the pre-shutdown phase, the microcontroller can control the voltage regulator to generate a pre-shutdown voltage based on the shutdown command sent by the main control unit. At this time, the switching module is in the on state, and the pre-shutdown voltage can be applied to the gate of thyristor-type devices through the switching module.
[0096] During the hard-drive turn-off phase, the microcontroller can control the voltage regulator to generate a hard-drive turn-off voltage. At this time, the switching module remains in the on state, and the hard-drive turn-off voltage can be applied to the gate of thyristor-type devices through the switching module.
[0097] In the above embodiments, the switching module may contain only a single switching device, and the voltage generation module may generate voltages of different magnitudes, applying different voltages to the gate of thyristor-type devices through a single switching device.
[0098] In some embodiments, applying a pre-turn-off voltage to the gate of a thyristor-type device in response to a turn-off command sent by the main control unit includes: In response to the shutdown command sent by the main control unit, the control voltage generation module generates a preset voltage and controls the first switching device to open and the second switching device to open. The above-mentioned application of a hard-drive turn-off voltage to the gate of a thyristor-type device includes: The control voltage generation module generates a preset voltage, controls the first switching device to turn on, and the second switching device to turn off.
[0099] In this embodiment, the switching module may include a first switching device, an impedance element, and a second switching device.
[0100] During the pre-turn-off phase, the second switching device is turned on, and the voltage generation module, impedance element, second switching device, and gate of thyristor-type devices can form a pre-turn-off branch to reduce the carrier concentration of thyristor-type devices during the pre-turn-off phase.
[0101] During the hard-drive turn-off phase, the first switching device is turned on, and the voltage generation module, the first switching device, and the gate of the thyristor-type device can form a hard-drive turn-off branch to achieve hard turn-off of the thyristor-type device.
[0102] In the above embodiments, the voltage generation module can generate only a single voltage, and the switching module can switch different branches to conduct, thereby realizing the gate charge sweeping of thyristor devices in the pre-turn-off stage and the turn-off of thyristor devices in the hard-drive turn-off stage.
[0103] Based on the same inventive concept, this application also provides a power electronic device, including a thyristor-type device and a gate drive circuit for the thyristor-type device in the above embodiments.
[0104] In some embodiments, the thyristor devices described above are thyristor devices with a non-gate cathode short-circuit structure, such as IGCT (Integrated Gate Commutated Thyristor), ETO (Emitter Turn-Off Thyristor), GTO (Gate Turn-Off Thyristor), or other types of thyristors, without limitation.
[0105] The functional blocks shown in the above-described structural diagram can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this application are programs or code segments used to perform the required tasks. Programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried on a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, radio frequency (RF) links, etc. Code segments can be downloaded via computer networks such as the Internet, intranets, etc.
[0106] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0107] This document uses specific examples to illustrate the principles and implementation methods of this application. The examples are merely for the purpose of helping to understand the method and core ideas of this application. The above are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, and the existence of an infinite number of specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the concept and technical solution of this application to other situations without modification, should all be considered within the scope of protection of this application.
Claims
1. A gate drive circuit for a thyristor-type device, characterized in that, include: A voltage generation module, wherein the control terminal of the voltage generation module is connected to a communication interface, and the voltage generation module is used to generate a pre-shutdown voltage or a hard-drive shutdown voltage based on a received shutdown command. A switching module, wherein a first terminal of the switching module is connected to the voltage generation module, a second terminal of the switching module is connected to the gate of a thyristor-type device, and a control terminal of the switching module is connected to a communication interface, and the switching module is used to turn on based on a received turn-off command; During the pre-shutdown phase, the voltage generation module generates a pre-shutdown voltage in response to the shutdown command and maintains the pre-shutdown duration, while the switching module turns on in response to the shutdown command. During the hard-drive shutdown phase, the voltage generation module switches the pre-shutdown voltage to the hard-drive shutdown voltage, while the switching module remains in the on state.
2. The gate drive circuit for a thyristor-type device according to claim 1, characterized in that, The voltage generation module includes: Voltage regulator; A microcontroller, connected to the control terminal of the voltage regulator, is configured to, in response to a shutdown command, control the voltage regulator to generate a pre-shutdown voltage during a pre-shutdown phase and to control the voltage regulator to generate a hard-drive shutdown voltage during a hard-drive shutdown phase.
3. The gate drive circuit for thyristor-type devices according to claim 2, characterized in that, The shutdown instruction also includes a pre-shutdown duration; the microcontroller is further configured to determine the pre-shutdown duration of the pre-shutdown phase based on the received shutdown instruction.
4. The gate drive circuit for thyristor-type devices according to claim 2, characterized in that, The microcontroller is also used to receive monitoring parameters during the operation of thyristor-type devices, and to determine the voltage amplitude of the pre-turn-off voltage and / or the pre-turn-off duration of the pre-turn-off phase based on the monitoring parameters.
5. The gate drive circuit for a thyristor-type device according to claim 2, characterized in that, The switching module includes: A first switching device is connected between the voltage generation module and the gate of the thyristor-like device; the voltage generation module, the first switching device, and the gate of the thyristor-like device are used to form a hard-drive turn-off branch; An impedance element and a second switching device are connected in series between the voltage generation module and the gate of the thyristor-like device; the voltage generation module, the impedance element, the second switching device, and the gate of the thyristor-like device are used to form a pre-turn-off branch.
6. The gate drive circuit for a thyristor-type device according to claim 5, characterized in that, The impedance element includes a resistive device or an inductive device.
7. The gate drive circuit for a thyristor-type device according to any one of claims 1-6, characterized in that, Also includes: A current generation module is connected to the gate of the thyristor-like device. The current generation module is used to provide a pre-turn-off current to the gate of the thyristor-like device during the pre-turn-off phase, so as to extract a portion of the charge carriers from the thyristor-like device while keeping the thyristor-like device in the on state.
8. The gate drive circuit for a thyristor-type device according to claim 7, characterized in that, The voltage generation module includes a voltage regulator and a microcontroller. The microcontroller is also used to adjust the pre-turn-off current based on monitoring parameters during the operation of thyristor-type devices.
9. A control method for thyristor-type devices, characterized in that, The method applied to the gate drive circuit of the thyristor-type device according to any one of claims 1-8 includes: When the thyristor-type device is in the on state, in response to the turn-off command sent by the main control unit, a pre-turn-off voltage is applied to the gate of the thyristor-type device. When the duration of the applied pre-turn-off voltage reaches the pre-turn-off duration, a hard-drive turn-off voltage is applied to the gate of the thyristor-type device.
10. The control method for thyristor-type devices according to claim 9, characterized in that, Before applying a hard-drive turn-off voltage to the gate of the thyristor device when the duration of the applied pre-turn-off voltage reaches the pre-turn-off duration, the method further includes: Receive monitoring parameters of thyristor devices during operation via the communication interface; The voltage amplitude of the pre-shutdown voltage is determined based on the monitoring parameters, and / or the pre-shutdown duration of the pre-shutdown phase.
11. The control method for thyristor-type devices according to claim 9, characterized in that, The step of applying a pre-turn-off voltage to the gate of a thyristor-type device in response to a turn-off command sent by the main control unit includes: In response to the shutdown command sent by the main control unit, the voltage generation module is controlled to generate a pre-shutdown voltage and the switching module is controlled to turn on. Applying a hard-drive turn-off voltage to the gate of the thyristor-type device includes: The voltage generation module is controlled to generate a hard drive shutdown voltage and the switching module is controlled to maintain the on state.
12. The control method for thyristor-type devices according to claim 9, characterized in that, The step of applying a pre-turn-off voltage to the gate of a thyristor-type device in response to a turn-off command sent by the main control unit includes: In response to the shutdown command sent by the main control unit, the voltage generation module is controlled to generate a preset voltage and the first switching device is turned off and the second switching device is turned on. Applying a hard-drive turn-off voltage to the gate of the thyristor-type device includes: The voltage generation module is controlled to generate a preset voltage, and the first switching device is controlled to turn on and the second switching device is controlled to turn off.
13. A power electronic device, characterized in that, It includes thyristor-type devices and gate drive circuits for thyristor-type devices as described in any one of claims 1-8.