IGBT drive resistor remote switching device

Abstract

The utility model relates to the field of power electronics, concretely relates to a kind of IGBT drive resistance remote switching device, including IGBT drive signal input port, IGBT gate connection port, opening resistance switchable network, off resistance switchable network, switching switch drive circuit and control unit, the opening and off resistance network are all by multiple parallel resistance branch, each branch series resistance and switching switch, control unit is gated specific branch by drive circuit, realizes independent, accurate regulation to opening and off resistance value.The utility model replaces traditional manual replacement resistance with digital control mode, overcomes the defect of inconvenient operation, cannot remote control and special chip cost is high, poor flexibility, significantly improves the debugging efficiency and operating reliability of power electronic system.

Description

Technical Field

[0001] This utility model relates to the field of power electronics technology, specifically to a remote switching device for IGBT drive resistors. Background Technology

[0002] Insulated-gate bipolar transistors (IGBTs) are core power switching devices in modern power electronic devices, widely used in key equipment such as frequency converters, inverters, and switching power supplies. Their performance depends heavily on the design of the drive circuit, and the gate drive resistor—especially the independently set turn-on resistor (Ron) and turn-off resistor (Roff)—is a core adjustment parameter in the drive circuit. A suitable Ron can effectively control the device's turn-on speed and suppress the rate of change of current (di / dt), thereby mitigating voltage overshoot caused by parasitic inductance in the circuit. Conversely, an appropriate Roff can adjust the rate of change of voltage (du / dt) during the turn-off process, preventing false turn-on due to the Miller capacitance effect and ensuring the efficiency and reliability of system operation.

[0003] In practical debugging and application, to adapt to different operating conditions, load characteristics, or different IGBT models, it is often necessary to adjust the resistance values ​​of Ron and Roff accordingly. Currently, the common methods are to manually replace the resistors on the circuit board or adjust them using a local potentiometer; the former is cumbersome and inefficient, while the latter has limitations in adjustment accuracy, stability affected by temperature and vibration, and the inability to achieve remote control. Traditional adjustment methods are particularly inconvenient when the equipment is installed in enclosed or high locations where it is difficult to access.

[0004] Although there are some dedicated chips or adjustment devices on the market that integrate adjustable drive resistors, their structures are often complex and costly, and their adjustment range and flexibility are often limited by the internal architecture of the chip, making it difficult to meet the diverse needs of rapid, flexible and precise adjustment in the field. Utility Model Content

[0005] To address the above technical problems, this utility model provides a technical solution for a remote switching device for IGBT drive resistors.

[0006] The technical problem solved by this utility model can be achieved by the following technical solution:

[0007] A remote switching device for IGBT drive resistors, comprising:

[0008] The IGBT drive signal input port is connected to the external IGBT drive circuit.

[0009] The IGBT gate connection port is connected to the gate of the IGBT;

[0010] A switchable turn-on resistor network is provided, wherein the common input terminal of the switchable turn-on resistor network is connected to the IGBT drive signal input port, and the common output terminal of the switchable turn-on resistor network is connected to the IGBT gate connection port; the switchable turn-on resistor network includes multiple parallel turn-on resistor branches, and each turn-on resistor branch has a turn-on resistor and a turn-on resistor switching switch connected in series.

[0011] A switchable turn-off resistor network is provided, wherein the common input terminal of the switchable turn-off resistor network is connected to the gate connection port of the IGBT, and the common output terminal of the switchable turn-off resistor network is connected to a common potential terminal; the switchable turn-off resistor network includes multiple parallel turn-off resistor branches, and each of the turn-off resistor branches contains a turn-off resistor and a turn-off resistor switching switch connected in series.

[0012] A switching drive circuit, wherein the output terminal of the switching drive circuit is respectively connected to the control terminal of the on-resistance switching switch and the control terminal of the off-resistance switching switch.

[0013] The control unit has its output connected to the input of the switching drive circuit.

[0014] Preferably, the common potential terminal is a reference ground or the emitter of the IGBT.

[0015] Preferably, the switchable turn-on resistor network includes five parallel turn-on resistor branches, and the resistance values ​​of the turn-on resistors in each of the turn-on resistor branches are different.

[0016] Preferably, the switchable shutdown resistor network includes five parallel shutdown resistor branches, and the resistance values ​​of the shutdown resistors in each of the shutdown resistor branches are different.

[0017] Preferably, both the on-resistance switching switch and the off-resistance switching switch are electromagnetic relays or semiconductor switching transistors.

[0018] Preferably, the switching drive circuit includes a driving transistor or relay driving chip corresponding to the number of the on-resistance switching switches and the off-resistance switching switches.

[0019] Preferably, the control unit is a single-chip microcomputer or microcontroller, which selects one on-resistance branch in the switchable on-resistance network and one off-resistance branch in the switchable off-resistance network.

[0020] Preferably, it further includes: a command input module, which is connected to the control unit and includes at least one of a Bluetooth module and a physical switch.

[0021] Preferably, the Bluetooth module is a Bluetooth serial port module, which communicates with the control unit via a UART interface; the physical switch is at least one of a rotary encoder switch, a DIP switch, and a button.

[0022] Preferably, the system further includes a power module, which is connected to the command input module and the control unit.

[0023] Beneficial effects: This utility model achieves precise and independent adjustment of the IGBT gate turn-on resistance and turn-off resistance by remotely switching the parallel resistor branch through digital control. It not only effectively overcomes the shortcomings of traditional manual adjustment methods, such as inconvenience, poor accuracy and inability to be remotely controlled, but also avoids the problems of complex structure, high cost and insufficient flexibility of dedicated integrated chip solutions. It significantly improves the debugging efficiency, adaptability and operational reliability of power electronic systems under complex working conditions. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the device structure of this utility model;

[0025] Figure 2 This is a schematic diagram of the IGBT gate connection port structure of this utility model;

[0026] Figure 3 This is a circuit diagram of the switchable on-resistance network of this utility model;

[0027] Figure 4 This is a circuit diagram of the switchable shut-off resistor network of this utility model. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments of the present invention can be combined with each other.

[0030] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention.

[0031] Reference Figure 1 This utility model provides a remote switching device for IGBT drive resistors, comprising:

[0032] IGBT drive signal input port 1 is connected to an external IGBT drive circuit;

[0033] IGBT gate connection port 2 is connected to the gate of the IGBT;

[0034] The switching resistor network 3 has a common input terminal IN_ON connected to the IGBT drive signal input port 1, and a common output terminal OUT_ON-G connected to the IGBT gate connection port 2. The switching resistor network 3 includes multiple parallel switching resistor branches, and each switching resistor branch has a switching resistor and a switching resistor switching switch connected in series.

[0035] A switchable turn-off resistor network 4 is provided. The common input terminal IN_OFF-G of the switchable turn-off resistor network 4 is connected to the gate connection port 2 of the IGBT, and the common output terminal OUT_OFF of the switchable turn-off resistor network 4 is connected to the reference ground or the emitter of the IGBT. The switchable turn-off resistor network 4 includes multiple parallel turn-off resistor branches, and each of the turn-off resistor branches has a turn-off resistor and a turn-off resistor switching switch connected in series.

[0036] A switching drive circuit 5 is provided, the output of which is connected to the control terminal of the on-resistance switching switch and the control terminal of the off-resistance switching switch, respectively.

[0037] Control unit 6, the output of which is connected to the input of the switching drive circuit 5, to select one of the switching resistor branches in the switching resistor network 3 and one of the switching resistor branches in the switching resistor network 4.

[0038] Specifically, in this embodiment of the present invention, in view of the problems of cumbersome operation and inability to be remotely controlled by traditional IGBT gate resistance adjustment methods, and the complex structure, high cost and lack of flexibility of existing dedicated adjustment schemes, an independent switchable network consisting of digital selection by control unit 6 and multiple parallel resistor branches is constructed, and precise control is achieved by combining switching drive circuit 5. This avoids the inconvenience of manual on-site operation and the inherent limitations of dedicated chips, and realizes remote, independent, flexible and high-precision adjustment of IGBT turn-on and turn-off resistance values, thereby optimizing the switching process and improving the overall system performance.

[0039] Specifically, the device operates according to a clear timing and control logic. First, the IGBT drive signal input port 1 receives the raw pulse signal from the external drive circuit, which is the drive signal source to be adjusted. At the same time, the control unit 6, as the core control component, receives and parses the control commands from the local interface or wireless module, and accurately calculates the on and off resistance values ​​of the circuit to be connected. Subsequently, the control unit 6 sends a corresponding low-level gating command to the switching drive circuit 5. Then, according to the command, the switching drive circuit 5 completes level conversion and power amplification, and outputs a strong electrical signal with sufficient drive current (or voltage) to reliably close the switching switches in the target on-resistance branch and the target off-resistance branch.

[0040] As the switch is activated, the physical connections of the circuit are reconfigured: the selected turn-on resistor is connected in the series path between the drive signal and the IGBT gate, directly determining the turn-on current rise rate of the device; while the selected turn-off resistor is connected in the discharge loop between the IGBT gate and the common ground, used to regulate the turn-off voltage rise rate and provide a discharge path for the Miller capacitor current, effectively suppressing false turn-on.

[0041] Ultimately, through this series of coherent "command-action-effect" logics, dynamic and precise optimization of the IGBT switching process is achieved, enabling remote adaptation to changing working conditions without manual intervention.

[0042] More specifically, in the embodiments of this utility model, referring to Figure 1 and Figure 2 The common output terminal OUT_ON-G of the switchable turn-on resistor network 3 is connected to pin 1 of the IGBT gate connection port 2, and the common input terminal IN_OFF-G of the switchable turn-off resistor network 4 is connected to pin 2 of the IGBT gate connection port 2. The common output terminal OUT_OFF of the switchable turn-off resistor network 4 and pin 3 of the IGBT gate connection port 2 are connected to the reference ground or the emitter of the IGBT, thus forming a clear and independent turn-on and turn-off current path in terms of physical connection.

[0043] This design not only effectively isolates transient interference during the switching process and ensures the purity of the drive signal, but also provides the shortest and lowest impedance discharge circuit for the turn-off current, significantly enhancing the reliability and speed of the turn-off process and suppressing voltage oscillations and the risk of false turn-on caused by circuit parasitic parameters.

[0044] In a preferred embodiment of this utility model, the switchable switching resistor network 3 includes five parallel switching resistor branches, and the resistance values ​​of the switching resistors in each of the switching resistor branches are different.

[0045] Specifically, in the embodiments of this utility model, reference is made to Figure 3 The switchable on-resistance network 3 includes:

[0046] The first turn-on resistor branch is connected in series with the first turn-on resistor R_on1 and the first turn-on resistor switching switch K_on1;

[0047] The second turn-on resistor branch is connected in series with the second turn-on resistor R_on2 and the second turn-on resistor switching switch K_on2;

[0048] The third turn-on resistor branch is connected in series with the third turn-on resistor R_on3 and the third turn-on resistor switching switch K_on3;

[0049] The fourth turn-on resistor branch is connected in series with the fourth turn-on resistor R_on4 and the fourth turn-on resistor switching switch K_on4;

[0050] The fifth turn-on resistor branch is connected in series with the fifth turn-on resistor R_on5 and the fifth turn-on resistor switching switch K_on5.

[0051] One end of all the turn-on resistor branches 3 is connected in parallel to the common input terminal IN_ON, and the other end is connected in parallel to the common output terminal OUT_ON-G. The switching drive circuit 5 provides drive power to K_on1 to K_on5 through its 12V voltage source. By controlling the conduction of any one of the switches, the corresponding turn-on resistor value can be uniquely connected to the loop between the drive signal and the IGBT gate, thereby accurately switching between five different turn-on resistor values ​​to flexibly adapt to the requirements of turn-on speed, current stress and suppression of voltage overshoot under different working conditions.

[0052] More specifically, since the values ​​of the turn-on resistors R_on1 to R_on5 are preset to different specific values ​​(e.g., 10Ω, 20Ω, 30Ω, 40Ω, 50Ω), the network can provide five discrete and precise selectable resistor levels by selecting different individual branches. This design of different resistor values ​​ensures that during commissioning or operation, the optimal turn-on resistor can be precisely matched for different bus voltages, load currents, or IGBT models, achieving fine-tuned step-by-step adjustment of the turn-on characteristics.

[0053] In a preferred embodiment of this utility model, the switchable shutdown resistor network 4 includes five parallel shutdown resistor branches, and the resistance values ​​of the shutdown resistors in each of the shutdown resistor branches are different.

[0054] Specifically, in the embodiments of this utility model, reference is made to Figure 4 The switchable shutdown resistor network 4 includes:

[0055] The first shut-off resistor branch is connected in series with the first shut-off resistor R_off1 and the first shut-off resistor switching switch K_off1;

[0056] The second shut-off resistor branch is connected in series with the second shut-off resistor R_off2 and the second shut-off resistor switching switch K_off2;

[0057] The third shut-off resistor branch is connected in series with the third shut-off resistor R_off3 and the third shut-off resistor switching switch K_off3;

[0058] The fourth shut-off resistor branch is connected in series with the fourth shut-off resistor R_off4 and the fourth shut-off resistor switching switch K_off4;

[0059] The fifth shut-off resistor branch is connected in series with the fifth shut-off resistor R_off5 and the fifth shut-off resistor switching switch K_off5.

[0060] One end of all the turn-off resistor branches 4 is connected in parallel to the common input terminal IN_OFF-G, and the other end is connected in parallel to the common output terminal OUT_OFF. The switching drive circuit 5 provides driving power to K_off1 to K_off5 through its 12V voltage source. By controlling the conduction of any one of the switches, the corresponding turn-off resistor value can be uniquely connected to the discharge circuit from the IGBT gate to the common ground, thereby accurately switching between five different turn-off resistor values ​​to flexibly adapt to the requirements of turn-off speed, voltage stress and suppression of mis-turn-on under different working conditions.

[0061] More specifically, since the resistance values ​​of the turn-off resistors R_off1 to R_off5 are preset to different specific values ​​(e.g., 5Ω, 15Ω, 25Ω, 35Ω, 45Ω), the network can provide five discrete and precise selectable turn-off resistor levels by selecting different individual branches. The design of different resistor values ​​ensures that the optimal turn-off resistor can be precisely matched according to key parameters such as voltage spikes during turn-off, electromagnetic interference (EMI) levels, and Miller plateau duration, achieving step-by-step fine-tuning of turn-off characteristics and optimization of system reliability.

[0062] Specifically, the number of branches in the switchable resistor network 3 and the switchable resistor network 4 can be flexibly configured according to actual application requirements, and is not limited to the five shown in this embodiment. By increasing or decreasing the number of parallel branches, the range of resistance values ​​and adjustment accuracy can be expanded. For example, in high-performance applications requiring finer adjustment, the number of branches can be increased to provide more resistance value ranges, while in cost-sensitive applications, the number of branches can be appropriately reduced to simplify the structure. This modular design concept gives the device excellent scalability and engineering adaptability.

[0063] In a preferred embodiment of this utility model, both the on-resistance switching switch and the off-resistance switching switch are electromagnetic relays or semiconductor switching transistors.

[0064] Specifically, since the IGBT drive circuit has high requirements for the on-state voltage drop and response speed of the switching devices, and the drive side and control side need to achieve electrical isolation to enhance anti-interference capability, based on this, in this embodiment of the utility model, an electromagnetic relay is selected as the switching switch. The electromagnetic relay can achieve extremely low on-resistance and ideal electrical isolation by utilizing its physical contacts, effectively reducing additional losses. Alternatively, semiconductor switching transistors such as MOSFETs and transistors can be selected. Semiconductor switching transistors can achieve extremely fast switching of the drive resistor with their nanosecond-level switching speed, meeting the requirements of high-frequency applications, and have no mechanical wear and longer lifespan.

[0065] In addition, other solid-state switching devices with isolation characteristics, such as optocoupler relays, can be used as switching devices. However, their on-state resistance is usually higher than that of electromagnetic relays, and their cost is relatively high. Therefore, in this embodiment of the invention, it is preferable to use electromagnetic relays that achieve a balance between cost and conduction performance, or to use semiconductor switching transistors when there are strict requirements for speed and lifespan, so as to ensure the core performance of the system while taking into account the practicality and economy of the solution.

[0066] In a preferred embodiment of this utility model, the switching drive circuit 5 includes a driving transistor or relay driving chip corresponding to the number of the on-resistance switching switches and the off-resistance switching switches.

[0067] Specifically, since the digital signal output by control unit 6 has limited driving capability, it cannot directly and reliably drive the electromagnetic relay coil or quickly and fully turn on semiconductor switching transistors such as MOSFETs. In this embodiment of the invention, the switching drive circuit 5, as a key interface and power amplification stage, has the core function of receiving low-level or weak-current control signals from control unit 6, amplifying or level-converting them, and generating a strong-current signal sufficient to drive various switching switches (such as providing the rated pull-in current required by the relay coil, or satisfying the driving voltage for rapid charging and discharging of the MOSFET gate capacitor). Its specific configuration strictly corresponds to the type of switching switch selected, as follows:

[0068] When the changeover switch is an electromagnetic relay, the changeover switch drive circuit 5 preferably uses a transistor or Darlington transistor array (such as ULN2003) to provide the rated pull-in current required by the relay coil.

[0069] When the switching switch is a semiconductor switching transistor such as a MOSFET, the switching switch driving circuit 5 preferably uses a dedicated gate driving chip or an optimized transistor amplifier circuit to provide a sufficiently steep gate driving voltage to ensure its rapid turn-on and turn-off.

[0070] This design performs precise current amplification and level conversion on the control signal, thereby providing stable, sufficient and fast drive power for various switching switches, ensuring their reliable operation and effectively reducing the load on the control unit 6.

[0071] More specifically, since each resistor switch requires an independent control signal to ensure that it can be selected individually and accurately, in this embodiment of the invention, the number of output channels of the switch driving circuit 5 strictly corresponds to the total number of all switches, with each channel dedicated to driving one switch, specifically:

[0072] When using a driving transistor, an independent transistor driving unit 6 needs to be configured for each switching switch. Its base is directly controlled by the I / O port of the control unit 6, and the current path flowing through the relay coil or MOSFET gate is controlled by the switching action of the transistor.

[0073] When using a driver chip, refer to Figure 3 and Figure 4 Two driver chips (such as the first driver chip U1 and the second driver chip U2) are used to drive the on-resistance switching switches (K_on1 to K_on5) and the off-resistance switching switches (K_off1 to K_off5) respectively. The control unit 6 sends the selection code to the driver chip through the parallel data line. The multi-channel Darlington transistor array inside the chip converts the weak logic signal into a strong drive current, thereby synchronously and efficiently driving all the specified switching actions.

[0074] This one-to-one correspondence ensures that the control unit 6 can select any one of the turn-on and turn-off resistor branches without conflict through the drive circuit, thereby achieving flexible, accurate and reliable configuration of the resistance value.

[0075] In a preferred embodiment of this utility model, the control unit 6 is a microcontroller.

[0076] Specifically, in order to achieve precise selection control of the multi-channel switching switch and to have the ability to flexibly respond to local and remote commands, in this embodiment of the present invention, the control unit 6 preferably uses a microcontroller with high integration, rich interfaces and controllable cost as the core, such as STM32 series, MSP430 series, Arduino series and other MCUs (Microcontroller Units).

[0077] In applications requiring high computing power and communication interfaces, the STM32 series microcontroller based on the ARM core can be selected; in applications emphasizing ultra-low power consumption, the MSP430 series microcontroller can be selected; and in scenarios where cost is extremely sensitive or rapid development is required, classic 8051 core microcontrollers or integrated development environments such as Arduino Nano can also be selected. The control unit 6 receives and parses various control commands in real time by running internal firmware, and generates corresponding digital control signal sequences accordingly. These signals are then output through its I / O ports to the subsequent switching drive circuit 5, thereby coordinating the reliable operation of the entire resistor switching network.

[0078] In a preferred embodiment of the present invention, an instruction input module is further included, which is connected to the control unit 6 and includes at least one of a Bluetooth module 7 and a physical switch 8.

[0079] Specifically, in order to build a flexible and convenient human-machine interface to adapt to different application scenarios of on-site manual adjustment and remote wireless control, this utility model embodiment sets up an instruction input module based on physical switch 8 to provide users with a direct, reliable local control method that does not rely on external devices.

[0080] Furthermore, considering the growing demand for remote monitoring and parameter adjustment of equipment in modern industrial applications, a Bluetooth module 7 can be designed simultaneously to expand the device's wireless control capabilities and enable data interaction with smart terminals (such as mobile phones and tablets), greatly improving the convenience of equipment debugging and management.

[0081] Specifically, the Bluetooth module 7 can be connected to the control unit 6 via a serial interface as an independent external module (such as HC-05); or it can be directly integrated into the control unit 6, i.e., a microcontroller with integrated Bluetooth wireless communication function (such as ESP32-C3, ESP32-S3 series chips) can be selected, thereby realizing the dual functions of core control and wireless communication on a single chip. This helps to further simplify the hardware structure and reduce the overall cost and size of the system.

[0082] In a preferred embodiment of this utility model, the Bluetooth module 7 is a Bluetooth serial port module, which communicates with the control unit 6 through a UART interface; the physical switch 8 is at least one of a rotary encoder switch, a DIP switch, and a button.

[0083] Specifically, in this embodiment of the present invention, the Bluetooth module 7 is preferably a low-cost, highly mature serial port pass-through module such as HC-05, HC-06 or ESP32 with integrated Bluetooth function. It directly interfaces with the control unit 6 through the UART interface and can seamlessly convert the received external Bluetooth commands into a serial data stream for the control unit 6 to parse, which greatly simplifies the hardware and software design of wireless communication.

[0084] The physical switch 8 can be flexibly configured according to the complexity and cost requirements of different application scenarios:

[0085] In scenarios where intuitive operation and simplified interface are desired, a rotary encoder switch is preferred. It integrates rotary encoding and press confirmation, allowing users to browse resistance levels by rotating and make the final selection by pressing. The operation process is intuitive and can effectively save I / O port resources of control unit 6.

[0086] In scenarios where multiple parameters need to be preset in parallel or fixedly configured, a DIP switch can be used to directly set a set of resistance values ​​by toggling different positions. The state is fixed and is not lost when power is off.

[0087] In scenarios where functional requirements are extremely simple or cost control is extremely strict, independent button combinations can be used, such as using "increase" and "decrease" buttons to achieve step-by-step switching of resistance levels.

[0088] Furthermore, combinations of the aforementioned switches can be used to balance flexibility and efficiency. For example, a combination of a DIP switch and a rotary encoder switch can be employed, where the DIP switch is used to set the coarse adjustment range for the operating mode or resistance selection, while the rotary encoder switch is used for fine adjustment of the resistance value in the current mode. This combination greatly expands the dimensions and efficiency of local operation, meeting more complex on-site commissioning needs.

[0089] In a preferred embodiment of the present invention, a power supply module 9 is also included, which is connected to the instruction input module and the control unit 6.

[0090] Specifically, in this embodiment of the present invention, the power module 9 converts and stabilizes the external input power (such as DC 12V-24V) to the operating voltage required by each unit in the system (for example, providing 3.3V or 5V logic power to the control unit 6 and Bluetooth module 7, and providing 12V drive power to the switching drive circuit 5 and relay coil). It integrates multiple independent LDO or DC-DC conversion circuits, ensuring a stable, clean and efficient power supply for different functional units such as digital control, wireless communication and power drive, which is the foundation for ensuring the reliable operation of the entire device.

[0091] In summary, this invention, by constructing a remotely switchable network consisting of a control unit 6 for intelligent management and multiple parallel resistor branches, and integrating a combined human-machine interface with Bluetooth wireless and diverse local physical switches 8, successfully achieves remote and local, independent, flexible, and high-precision adjustment of the IGBT gate turn-on and turn-off resistance values. This fundamentally overcomes the inherent limitations of traditional solutions, such as cumbersome operation, poor flexibility, high cost of dedicated chips, and weak adaptability, providing an efficient and reliable solution for online debugging and performance optimization of power electronic devices.

[0092] This utility model has the following significant advancements and advantages:

[0093] Regarding system structure and cost control: This invention abandons the complex and expensive dedicated driver chip solution, and instead adopts a modular architecture consisting of a general-purpose microcontroller, standard resistive and capacitive components, and electromagnetic relays. This architecture is not only simple in structure and has low-cost core components, but also facilitates production and maintenance, effectively reducing the manufacturing cost of the equipment and the threshold for subsequent maintenance.

[0094] Regarding human-machine interaction and control modes: This invention creatively combines Bluetooth wireless control with local physical switch control, providing unprecedented operational flexibility. Engineers can perform rapid debugging on-site via DIP switches, or perform fine-tuning and status monitoring remotely via a smart terminal, greatly expanding the applicable scenarios of the device, especially suitable for modern industrial applications where the equipment installation location is inconvenient for direct contact or requires remote centralized management.

[0095] Regarding debugging functions and performance: This invention provides five discrete and independently selectable preset positions for the turn-on and turn-off resistors. This multi-position design is sufficient to cover the drive parameter requirements of most IGBT models under different operating conditions, achieving a leap from "absence" to "superiority". Simultaneously, the resistor switching process is fully electrified, eliminating the need for manual soldering or plugging / unplugging, making drive parameter adjustment exceptionally convenient and quick, improving debugging efficiency by several orders of magnitude, and completely avoiding potential circuit board damage or poor contact problems caused by frequent manual component replacement.

[0096] In terms of system integration and applicability: The device is designed as a standardized, independent functional module that can be directly connected in series between existing IGBT driver boards and IGBT gates. This "plug-and-play" design concept means that users do not need to make any structural modifications to the original main circuit or driver circuit to give existing systems advanced remote adjustable functions, demonstrating strong versatility and engineering applicability, and facilitating rapid promotion and popularization in various new and old equipment.

[0097] The following is an illustration using a specific example:

[0098] Example:

[0099] 1. Hardware configuration and electrical connections:

[0100] 1.1 Core Control Unit: The STM32F103C8T6 microcontroller is used as control unit 6, which is responsible for executing all logical judgments and distributing instructions.

[0101] 1.2 Signal Interface:

[0102] IGBT drive signal input port 1 is connected to the signal output terminal of an external IGBT driver board.

[0103] IGBT gate connection port 2 is directly connected to the gate of the IGBT device.

[0104] 1.3 Resistor Switching Network:

[0105] Switchable turn-on resistor network 3: It consists of five parallel branches, each branch is connected in series with turn-on resistors (R_on1 to R_on5) with resistance values ​​of 10Ω, 20Ω, 30Ω, 40Ω and 50Ω respectively, and corresponding electromagnetic relays (K_on1 to K_on5); the common terminal IN_ON of all branches is connected to IGBT drive signal input port 1, and the common output terminal OUT_ON-G is connected to IGBT gate connection port 2.

[0106] The switchable turn-off resistor network 4 also consists of five parallel branches, each branch connected in series with resistors (R_off1 to R_off5) with resistance values ​​of 5Ω, 15Ω, 25Ω, 35Ω and 45Ω respectively, and the corresponding electromagnetic relays (K_off1 to K_off5); the common input terminal IN_OFF-G of all branches is connected to the IGBT gate connection port 2, and the common output terminal OUT_OFF is connected to the reference ground.

[0107] 1.4 Command Input Module:

[0108] Bluetooth Module 6: Uses HC-05 Bluetooth serial port module, whose UART interface (TXD, RXD) is connected to the microcontroller's USART1 (PA9, PA10).

[0109] Physical switch 7: A 5-bit DIP switch is used, with each switch signal line directly connected to the general-purpose GPIO pin of the microcontroller.

[0110] 1.5 Drive and Power Supply:

[0111] Switching drive circuit 5: Uses ULN2003 Darlington transistor array chip; the microcontroller's 10 GPIO output ports (5 for turning on the network and 5 for turning off the network) are respectively connected to the input terminals of two ULN2003 chips, the output terminals of ULN2003 are connected to the coil of the corresponding relay, and the other end of the relay coil and the COM port of ULN2003 are connected to the 12V drive power supply.

[0112] Power module 9: The external 24V DC input is first converted to 5V by the MP1584EN step-down module to power the drive circuit and relay coil; this 5V is then converted to 3.3V by the AMS1117-3.3V LDO to power the microcontroller and Bluetooth module.

[0113] 2. Workflow and Implementation Steps:

[0114] 2.1 Initialization: After the device is powered on, the power module 9 outputs stable 5V and 3.3V voltages. The microcontroller completes its own initialization, configures its GPIO and UART interfaces, and reads the initial state of physical switch 8 as the default configuration.

[0115] 2.2 User Operations and Command Acquisition: Users can choose one of the following two methods to operate, depending on the actual situation:

[0116] Local manual operation: The user walks directly to the device and manually moves the 5-bit DIP switch. For example, the high 2 bits representing the on position are set to "10" (corresponding to the 3rd position, where positions 1-5 correspond to R_off1-R_off5), and the low 2 bits representing the off position are set to "01" (corresponding to the 2nd position).

[0117] Remote wireless operation: Users can open the dedicated app on their mobile phones from a location away from the device, select "On Resistance" at level 4 and "Off Resistance" at level 5 on the interface, and then click the "Send" button. The app will combine these selections into a command string (e.g., "ON4OFF5") and send it wirelessly via Bluetooth.

[0118] 2.3 Instruction Parsing and Decision Making:

[0119] If the user operates locally, the microcontroller will continuously scan and detect changes in the GPIO level of the DIP switch, and then decode the user-set target gear (gear 3 on, gear 2 off) according to the preset encoding rules.

[0120] If the user operates remotely, the HC-05 Bluetooth module 7 will receive the command string sent by the APP and transmit it to the microcontroller via the serial port. The microcontroller parses the string and extracts the target gear information (4th gear on, 5th gear off).

[0121] 2.4 Drive signal output and resistor switching:

[0122] Based on the parsed target gear, the microcontroller outputs the corresponding control level to the ULN2003 chip of the switching drive circuit 5 through its GPIO port.

[0123] The ULN2003 amplifies the signal and drives the coil of the target relay to be energized and engaged (for the local operation example, K_on3 and K_off2 are engaged; for the remote operation example, K_on4 and K_off5 are engaged).

[0124] After the relay is energized, the resistance of its branch is connected to the drive circuit. In the local operation example, the IGBT's turn-on resistance is switched to 30Ω and the turn-off resistance is switched to 15Ω; in the remote operation example, the turn-on resistance is switched to 40Ω and the turn-off resistance is switched to 45Ω.

[0125] 2.5 Steady-state operation and cycle monitoring: After completing this resistance switching, the device returns to command listening state. Users can then initiate new resistance value adjustment commands at any time by toggling the DIP switch or operating the mobile app, and the system will respond by repeating steps 2.2 to 2.4.

[0126] Through the above steps, this embodiment clearly demonstrates how users can intervene in the control in different ways, and ultimately achieve flexible and convenient switching of the IGBT drive resistor.

[0127] The above description is only a preferred embodiment of the present utility model and does not limit the implementation method and protection scope of the present utility model. Those skilled in the art should realize that all solutions obtained by equivalent substitutions and obvious changes made based on the description and illustrations of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A remote switching device for IGBT drive resistors, characterized in that, include: The IGBT drive signal input port (1) is connected to the external IGBT drive circuit; IGBT gate connection port (2), connected to the gate of the IGBT; A switchable turn-on resistor network (3) is provided, wherein the common input terminal of the switchable turn-on resistor network (3) is connected to the IGBT drive signal input port (1), and the common output terminal of the switchable turn-on resistor network (3) is connected to the IGBT gate connection port (2); the switchable turn-on resistor network (3) includes multiple parallel turn-on resistor branches, and each turn-on resistor branch is connected in series with a turn-on resistor and a turn-on resistor switching switch; A switchable turn-off resistor network (4) is provided, wherein the common input terminal of the switchable turn-off resistor network (4) is connected to the gate connection port (2) of the IGBT, and the common output terminal of the switchable turn-off resistor network (4) is connected to a common potential terminal; the switchable turn-off resistor network (4) includes multiple parallel turn-off resistor branches, and each of the turn-off resistor branches is connected in series with a turn-off resistor and a turn-off resistor switching switch. The output terminal of the switching drive circuit (5) is connected to the control terminal of the turn-on resistor switching switch and the control terminal of the turn-off resistor switching switch, respectively. Control unit (6), the output terminal of which is connected to the input terminal of the switching drive circuit (5).

2. The IGBT drive resistor remote switching device according to claim 1, characterized in that, The common potential terminal is either reference ground or the emitter of the IGBT.

3. The IGBT drive resistor remote switching device according to claim 1, characterized in that, The switchable switching network (3) includes five parallel switching resistor branches, each with a different switching resistor value.

4. The IGBT drive resistor remote switching device according to claim 1, characterized in that, The switchable shutdown resistor network (4) includes five parallel shutdown resistor branches, each with a different shutdown resistor value.

5. The IGBT drive resistor remote switching device according to claim 1, characterized in that, Both the on-resistance switching switch and the off-resistance switching switch are electromagnetic relays or semiconductor switching transistors.

6. The IGBT drive resistor remote switching device according to claim 1, characterized in that, The switching drive circuit (5) includes a driving transistor or relay driving chip corresponding to the number of the on-resistance switching switches and the off-resistance switching switches.

7. The IGBT drive resistor remote switching device according to claim 1, characterized in that, The control unit (6) is a microcontroller that selects one of the turn-on resistor branches in the switchable turn-on resistor network (3) and one of the turn-off resistor branches in the switchable turn-off resistor network (4).

8. A remote switching device for IGBT drive resistors according to any one of claims 1-7, characterized in that, It also includes an instruction input module connected to the control unit (6), which includes at least one of a Bluetooth module (7) and a physical switch (8).

9. The IGBT drive resistor remote switching device according to claim 8, characterized in that, The Bluetooth module (7) is a Bluetooth serial port module, which communicates with the control unit (6) through the UART interface; The physical switch (8) is at least one of a rotary encoder switch, a DIP switch, and a button.

10. The IGBT drive resistor remote switching device according to claim 8, characterized in that, It also includes a power module (9), which is connected to the instruction input module and the control unit (6).

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