High-voltage IGBT gate driver for railway

Abstract

The present invention provides a gate driver for a railway. More specifically, the present invention relates to a railway gate driver using a high-voltage IGBT having a bipolar transistor structure, and a driving method for processing fault information thereof. According to an embodiment of the present invention, the operation characteristics of the gate driver during actual operation of railway equipment can be stored under user-specified conditions and analyzed via an external device. This enables convenient identification of the operation characteristics of the gate driver in relation to the stack characteristics of a power conversion device, thereby allowing accurate configuration of gate resistance and protection operations. As a result, unnecessary protection operations of the gate driver can be prevented, IGBT burnout can be avoided, and stack losses can be minimized.

Description

High-voltage IGBT gate drivers for railway applications

[0001] The present invention relates to a gate driver for railway use, and more particularly, to a gate driver for railway use for driving a high-voltage IGBT having a bipolar transistor structure.

[0002] Power conversion systems for railway vehicles typically consist of a propulsion control power converter and an auxiliary power supply. These power conversion systems primarily utilize high-switching frequency power semiconductors to reduce size and improve performance. IGBTs are widely used as power semiconductor components.

[0003] To drive these IGBT devices, a device that supplies the necessary voltage and current is required, and this is called a gate driver unit (GDU).

[0004] The aforementioned gate driver is a core component of a power conversion device, and depending on its characteristics, it can be said to be a device that has a great influence on the operation of the power conversion device and the reliability of the entire system.

[0005] Currently, gate drivers used in railway vehicle systems are equipped with built-in protection features (e.g., overcurrent, undervoltage, etc.), which halt operation in the event of a fault. However, when protection functions are activated according to the existing method, only information about the fault item is available. Therefore, the exact operating status (waveform) of the gate driver itself cannot be confirmed in the event of a fault. Consequently, in most cases, managers typically resolve the issue by inspecting and replacing the main circuit. This management method is a major cause of disruptions in the smooth operation of railway vehicles.

[0006] Meanwhile, the gate driver must be selected based on operating characteristics, protective operation, and other factors, such as the impedance of the IGBT element used, the stack configuration of the device being configured, and busbar connections. Failure to do so can result in unnecessary protective operation, IGBT damage, and increased loss, resulting in overheating.

[0007] Moreover, not only is separate equipment, such as double pulse test equipment, required to solve these problems, but even if the information obtained through this is used, there are limitations in solving problems that occur during actual railway operation.

[0008] (Patent Document 1) Patent Registration No. 110-2388544 (Publication Date: April 15, 2022)

[0009] The present invention has been devised to solve the aforementioned problem, and the present invention has a problem in that it provides a gate driver and a driving method thereof that can improve reliability through an analysis function of the operation state and failure state of the gate driver by implementing a function of storing operation and failure data such as voltage, current, temperature, and failure of the railway gate driver itself according to conditions specified by a user.

[0010] In order to solve the above-described problem, a high-voltage IGBT gate driver for railway use according to an embodiment of the present invention is a gate driver that is electrically connected to a switching element and controls driving, and may include an insulated power supply that receives driving power from an external source and supplies it to each component, an optical signal conversion unit that receives a PWM signal in the form of an optical signal output from a main controller that controls driving of the switching element and converts it into the form of an electric signal, a driver circuit that generates a gate driving signal that turns on or off the switching element and supplies it to the switching element, a data storage unit that stores constant data and fault / setting data according to driving of the switching element, and a control unit that supplies a converted PWM signal to the driver circuit to generate the gate driving signal and stores the constant data and fault / setting data generated when the device is driven according to settings in the data storage unit.

[0011] The above switching element may be an IGBT (Insulated Gate Bipolar Mode Transistor) element for high-speed switching having a bipolar transistor structure.

[0012] The high-voltage IGBT gate driver for railways of the present invention may include an overcurrent detection circuit that is electrically connected to the collector of the switching element and detects an overcurrent flowing through the switching element and provides the detection result to the control unit.

[0013] The high-voltage IGBT gate driver for railway of the present invention may include a low-voltage detection circuit that is electrically connected to the insulated power supply and detects an overvoltage in which the voltage level applied to each driving unit falls below a certain level and provides the detection result to the control unit.

[0014] The high-voltage IGBT gate driver for railways of the present invention may include a latch circuit that latches the current state so as to block the gate drive signal for a certain period of time or until a certain condition is satisfied under the control of the control unit when overcurrent and low voltage occur.

[0015] The above driver circuit may further include an amplifier that amplifies the gate driving signal and applies it to the gate of the switching element to drive the switching element.

[0016] The high-voltage IGBT gate driver for railways of the present invention may further include a data conversion unit that is connected to an external device through a terminal and extracts and converts the constant data and fault / setting data from the data storage unit and transmits them to the external device.

[0017] The data storage unit includes a first storage space in which the constant data is stored and a second storage space in which the fault / setting data is stored, and the control unit can delete stored data and add new data in a first-in, first-out manner according to the capacity of the first and second storage spaces.

[0018] The above control unit can record the failure / setting data in the second storage space at a time before and after the occurrence of an event condition set by the user through the external device.

[0019] According to an embodiment of the present invention, by storing the operating characteristics of the gate driver according to conditions specified by the user during actual operation of railway equipment and analyzing them through an external device, the operating characteristics of the gate driver with respect to the stack characteristics of a power conversion device can be conveniently confirmed, and accordingly, the gate resistance and protection operation settings can be accurately performed, thereby preventing unnecessary protection operation of the gate driver, preventing damage to the IGBT, and minimizing stack loss.

[0020] In particular, according to an embodiment of the present invention, when a failure occurs, the characteristics of the PWM input waveform and operating waveform of the gate driver, and the status of temperature and current can be checked, so that the cause of the failure can be identified more quickly and accurately.

[0021] FIG. 1 is a schematic drawing of a high-voltage IGBT gate driver for railway use and its entire connection structure according to an embodiment of the present invention.

[0022] FIG. 2 is a drawing specifically showing the structure of a high-voltage IGBT gate driver for railway use according to an embodiment of the present invention.

[0023] FIG. 3 is a drawing showing a driving method of a high-voltage IGBT gate driver for railway use according to an embodiment of the present invention.

[0024] The present invention as described above will be described in detail through the attached drawings and examples.

[0025] It should be noted that the technical terms used in the present invention are used merely to describe specific embodiments and are not intended to limit the present invention. Furthermore, unless specifically defined otherwise herein, the technical terms used herein should be interpreted as having a meaning generally understood by those skilled in the art to which the present invention pertains, and should not be interpreted in an excessively broad or narrow sense. Furthermore, if a technical term used herein is incorrect and fails to accurately express the spirit of the present invention, it should be replaced with a technical term that can be correctly understood by those skilled in the art. Furthermore, general terms used herein should be interpreted according to their dictionary definitions or according to the context, and should not be interpreted in an excessively narrow sense.

[0026] Additionally, singular expressions used in the present invention include plural expressions unless the context clearly dictates otherwise. In the present invention, terms such as "consist of" or "include" should not be construed to necessarily include all of the components or steps described in the invention, and should be construed to mean that some of the components or steps may not be included, or that additional components or steps may be included.

[0027] Additionally, terms including ordinal numbers, such as "first" and "second," used in the present invention may be used to describe components, but the components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component."

[0028] Furthermore, in describing the present invention, detailed descriptions of related known technologies will be omitted if they are deemed to obscure the gist of the present invention. Furthermore, it should be noted that the attached drawings are intended solely to facilitate understanding of the spirit of the present invention and should not be construed as limiting the spirit of the present invention.

[0029] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or similar components are given the same reference numbers and redundant descriptions thereof will be omitted.

[0030] In the following description, the term “high voltage IGBT gate driver for railway” of the present invention may be used interchangeably as “gate driver.”

[0031] Hereinafter, a high-voltage IGBT gate driver for railway use according to an embodiment of the present invention will be described in detail with reference to the drawings.

[0032] FIG. 1 is a schematic drawing of a high-voltage IGBT gate driver for railway use and its entire connection structure according to an embodiment of the present invention.

[0033] Referring to FIG. 1, a high-voltage IGBT gate driver (100) for railway use according to an embodiment of the present invention is a device that drives a switching element (1) mounted on a railway vehicle under the control of a main controller (10), and not only drives the switching element (1), but also has a CPU and memory mounted therein so that the operating state and fault state of the switching element (1) can be classified and recorded according to user conditions, and furthermore, the function of outputting the information to an external device (200) that is connected later can be provided.

[0034] The aforementioned switching element (1) is driven as a main power conversion element in a railway vehicle, and can control the operation of a railway motor (2) according to the control of a gate driver (100).

[0035] In particular, as a switching element (1) according to an embodiment of the present invention, a voltage-driven switching element whose switching characteristics are determined by a voltage applied to a gate may be used, and an IGBT (Insulated Gate Bipolar Mode Transistor) element for high-speed switching having a structure of a known bipolar transistor may be used.

[0036] In particular, the railway IGBT according to the embodiment of the present invention can be a device that is evaluated to have a capacity of up to 500 kW on its own and an operating frequency of up to 70 kHz. In general, a device with a high operating frequency has a low usable capacity, and the higher the device capacity, the lower the operating frequency. The IGBT is a power device with usable capacity and operating frequency conditions suitable for industrial use, and can have excellent characteristics such as an insulated gate voltage driving characteristic and a low loss characteristic.

[0037] These IGBTs have a fast switching characteristic because their basic structure is a BJT (bipolar junction transistor), and since the gate has insulating characteristics similar to a FET, while BJTs have current-driven characteristics, IGBTs have voltage-driven characteristics and have the advantage of very low driving current.

[0038] The gate driver (100) is electrically connected to the gate electrode of the aforementioned switching element (1), receives an optical signal output from the main controller (10), and generates a gate driving signal that turns on or off the switching element (1) at high speed through a process such as amplification, and inputs the gate driving signal to the switching element (1).

[0039] In these gate drivers (100), operating characteristics and protective operations can be set according to the impedance due to the stack shape of the device to be configured, bus bar connection, etc., including the switching elements to be connected.

[0040] In addition, the gate driver (100) may be equipped with an overcurrent detection means that receives a voltage applied to the collector terminal of the switching element (1) and compares it with a reference voltage to detect overcurrent, and a low voltage detection means that compares a gate drive signal with a reference voltage to detect low voltage. A detailed description of the internal components of the gate driver (100) will be described later.

[0041] An external device (200) can receive and output various records generated when the switching element (1) and gate driver (100) are driven. This external device (200) can be implemented as a PC, a mobile terminal, etc., can be connected via a serial port such as USB, can transmit setting values ​​input by a user through a UI to the gate driver (100), and can output fault information, etc. transmitted from the gate driver (100).

[0042] According to the structure described above, the high-voltage IGBT gate driver for railway according to an embodiment of the present invention can supply power to an electric motor of a railway vehicle, etc. by driving the gate driver according to the control of the main controller to generate a gate drive signal and control an IGBT type switching element. In addition, the present invention has an advantage in that it collects and stores PWM signals, gate drive signals, current values, temperature values, and fault data detected from the gate driver, and provides them to an external device according to a user's settings, thereby making it possible to determine the appropriateness of the IGBT operation or easily analyze the cause of a device failure.

[0043] Hereinafter, a high-voltage IGBT gate driver for railway use according to an embodiment of the present invention will be described in detail with reference to the drawings.

[0044] FIG. 2 is a drawing specifically showing the structure of a high-voltage IGBT gate driver for railway use according to an embodiment of the present invention.

[0045] Referring to FIG. 2, a high-voltage IGBT gate driver (100) for railway use according to an embodiment of the present invention is a gate driver that is electrically connected to a switching element (1) and controls driving, and includes an insulated power supply (105) that receives driving power from the outside and supplies it to each component, an optical signal conversion unit (110) that receives a PWM signal in the form of an optical signal output from a main controller (10) that controls driving of the switching element (1) and converts it into an electrical signal, a driver circuit (115) that generates a gate driving signal that turns on or off the switching element (1) and supplies it to the switching element (1), a data storage unit (120) that stores constant data and fault / setting data according to driving of the switching element (1), a control unit (130) that supplies the converted PWM signal to the driver circuit (115) to generate a gate driving signal and stores constant data and fault / setting data generated when the device is driven according to settings in the data storage unit, and a control unit (130) that is electrically connected to the collector of the switching element (1) and controls overcurrent flowing through the switching element. It may include an overcurrent detection circuit (140) that detects and provides the detection result to the control unit (130), an undervoltage detection circuit (145) that is electrically connected to the insulated power supply (105) and detects overvoltage in which the voltage level applied to each driving unit drops below a certain level and provides the detection result to the control unit (130), a latch circuit (150) that latches the current state so as to block the gate driving signal for a certain period of time or until a certain condition is satisfied according to the control of the control unit (130) when overcurrent and undervoltage occur, and a data conversion unit (160) that is connected to an external device (200) through a terminal and extracts and converts constant data and fault / setting data from the data storage unit (120) and transmits them to the external device (200).

[0046] The insulated power supply (105) serves to supply power for driving the gate driver (100), and can receive driving power from the power system and provide it to the control unit (130) and each component of the gate driver (100).

[0047] The optical signal conversion unit (110) receives an optical signal transmitted from the optical signal output means of the main controller (10), converts it into an electrical signal, and inputs it to the control unit (130), thereby generating a gate driving signal by the control unit (130). Here, the optical signal described above may be a signal in the form of a PWM waveform.

[0048] To this end, the optical signal conversion unit (110) may include an optical connector for connection with the main controller (10), and may receive not only the optical signal described above but also a fault signal and provide it to the latch circuit (150) described below, thereby stopping the operation of the gate driver (100) through a latch function in the event of a fault, thereby preventing circuit damage.

[0049] The driver circuit (115) can input a gate driving signal corresponding to a PWM signal provided from the control unit (130) to the switching element (1). In particular, the driver circuit (115) can control the driving thereof by amplifying the PWM signal to a certain level or higher and applying it to the gate of the switching element (1), and an amplifier for this purpose can be mounted.

[0050] The data storage unit (120) can be implemented as a known memory device and can store various data including a fault signal generated when the gate driver (100) is driven, and the stored data can be provided to an external device (200) through a conversion process via the control unit (130).

[0051] In particular, according to an embodiment of the present invention, the data storage unit (120) has a first storage space for storing constant data and a second storage space for storing data regarding failures and settings, which are defined separately from each other, so that each piece of data can be stored separately. Among these, the constant data is data that is constantly generated when the gate driver (100) is driven, and can be stored and managed in a first-in, first-out manner considering the limited capacity of the storage space. That is, if data exceeding the memory capacity in the current state is input, the data stored earliest can be sequentially deleted from the first storage space.

[0052] In addition, in the second storage space, pre- and post-failure data and setting data can be recorded based on the time of occurrence of an event condition set by the user, and such data can also be managed in a first-in, first-out manner.

[0053] According to the data storage unit (120) having the above-described partition structure, data that occurs frequently and data that occurs intermittently according to the occurrence of an event can be managed separately and thus the utilization of limited space can be increased.

[0054] In addition, data stored in the data storage unit (120) can be transmitted when an external device (200) is connected, and the user can download the constant data and fault / setting data to the external device (200) and perform analysis on the gate driver (100).

[0055] The control unit (130) can use a known CPU device and can control the operation of each component of the gate driver (100), and in particular, generates a gate drive signal having a waveform corresponding to a PWM signal and provides it to the switching element (1) through the driver circuit (115), thereby enabling the railway motor to be driven.

[0056] In addition, when the control unit (130) detects overcurrent / low voltage from the overcurrent detection circuit (140) and low voltage detection circuit (145) described later during device operation, the control unit (130) controls the latch circuit (150) to latch the current state and store the current constant data as well as fault data in the data storage unit (120).

[0057] In addition, the control unit (130) can read the constant data stored in the data storage unit (120) according to the connection and request of the external device (200), convert it into a form (text file, etc.) that can be used externally through the data conversion unit (160), and transmit it to the external device (200).

[0058] The overcurrent detection circuit (140) is electrically connected to the collector (C) of the switching element (1), and can detect overcurrent flowing through the switching element (1) and provide the detection result to the control unit (130).

[0059] A diode string (142) is formed by connecting multiple diode elements in series to form a single string, and is connected to the collector (C) of the above-described overcurrent detection circuit (140) and the switching element (1), thereby enabling the overcurrent detection circuit (140) to detect that overcurrent is flowing through the switching element (1).

[0060] The low voltage detection circuit (145) can be electrically connected to an insulated power supply (105) that supplies driving power, and can detect an overvoltage state in which the voltage level applied to each driving unit falls below a certain level and provide the detection result to the control unit (130).

[0061] The latch circuit (150) can latch the current state to block the gate drive signal for a certain period of time or until a certain condition is satisfied under the control of the control unit (130) when overcurrent or low voltage occurs, and can transmit fault data, etc. to an external device (200) in the form of an optical signal.

[0062] In addition, when the device returns to a normal operating state after latching, the latch circuit (150) can release the latch state under the control of the control unit (130), and the control unit (130) can resume operating the device.

[0063] The data conversion unit (160) is connected to an external device through a terminal, and can extract and convert operation data and fault / setting data from the data storage unit (120) and transmit them to the external device (200). A user can connect an external device (200), such as a PC, to the terminal of the data conversion unit (160) for operation management of the gate driver (100) and the railway motor, and can receive fault data, including constant data stored in the gate driver (100), check and analyze detailed information, and reflect it in device operation.

[0064] Hereinafter, a driving method of the high-voltage IGBT gate driver for railway use of the present invention described above will be described in detail with reference to the drawings.

[0065] FIG. 3 is a diagram illustrating a method for driving a high-voltage IGBT gate driver for railway use according to an embodiment of the present invention, and illustrates a procedure for determining the device status through the gate driver. In the following description, the subject of execution for each step is the gate driver and its components of the present invention, even if not otherwise described.

[0066] Referring to FIG. 3, in a method for driving a high-voltage IGBT gate driver for railway use according to an embodiment of the present invention, as a method for driving a gate driver for driving an IGBT element for controlling an electric motor mounted on a railway, first, a driving power is applied from a power source and a PWM signal is applied from a main controller (10), and a gate driving signal is generated using the same to control a switching element and drive the electric motor (S100).

[0067] Next, the control unit can store the operation data according to the current operation of the gate driver in the data storage unit (S200). At this time, the operation data is data that occurs continuously and is continuously stored in the first storage space secured in advance according to a certain cycle. However, if the space is insufficient, the control unit updates the data according to a first-in, first-out basis.

[0068] Here, the driving data (constant data) may include input PWM signals, gate driving signals, current values, temperature values, and fault information.

[0069] Next, the control unit can store the user's event conditions when they are set, and when the overcurrent detection circuit detects that overcurrent is flowing in the switching element or the undervoltage detection circuit detects that undervoltage is applied during the operation of the gate driver, the control unit detects fault data and related setting data that occur according to the fault (S300). In step S300, the control unit repeats the previous step if the current fault data is not selected for the set event conditions, and if the fault data satisfies the event conditions, it can be stored in the second storage space allocated in advance in the data storage unit.

[0070] While the above description contains many specific details, it should be construed as illustrative of preferred embodiments rather than limiting the scope of the invention. Therefore, the invention should be defined not by the described embodiments, but by the claims and their equivalents.

Claims

1. A gate driver that is electrically connected to a switching element and controls operation. An isolated power supply device that receives driving power from an external source and supplies it to each component; An optical signal conversion unit that receives a PWM signal in the form of an optical signal output from a main controller that controls the operation of the above switching element and converts it into an electrical signal; A driver circuit that generates a gate drive signal for turning on or off the switching element and supplies it to the switching element; A data storage unit that stores constant data and fault / setting data according to the operation of the above switching element; and A control unit that supplies the converted PWM signal to the driver circuit to generate the gate drive signal and stores the constant data and fault / setting data generated when the device is driven according to the setting in the data storage unit. High voltage IGBT gate driver for railway applications including.

2. In paragraph 1, The above switching element, A high-voltage IGBT gate driver for railway use, which is an IGBT (Insulated Gate Bipolar Mode Transistor) device having a bipolar transistor structure for high-speed switching.

3. In paragraph 1, The above high-voltage IGBT gate driver for railway applications is, An overcurrent detection circuit electrically connected to the collector of the above switching element, detecting overcurrent flowing through the above switching element and providing the detection result to the above control unit. High voltage IGBT gate driver for railway applications including.

4. In paragraph 1, The above high-voltage IGBT gate driver for railway applications is, A low voltage detection circuit that is electrically connected to the above-mentioned insulated power supply and detects overvoltage in which the voltage level applied to each driving unit falls below a certain level and provides the detection result to the above-mentioned control unit. High voltage IGBT gate driver for railway applications including.

5. In paragraph 3 or 4, The above high-voltage IGBT gate driver for railway applications is, A latch circuit that latches the current state so that the gate drive signal is blocked for a certain period of time or until a certain condition is satisfied according to the control of the control unit when overcurrent and undervoltage occur. High voltage IGBT gate driver for railway applications including.

6. In paragraph 1, The above driver circuit, An amplifier that amplifies the above gate driving signal and applies it to the gate of the above switching element to drive the switching element. High voltage IGBT gate driver for railway applications including further.

7. In paragraph 1, The above high-voltage IGBT gate driver for railway applications is, A data conversion unit connected to an external device through a terminal, extracting and converting the constant data and fault / setting data from the data storage unit and transmitting them to the external device. High voltage IGBT gate driver for railway applications including further.

8. In paragraph 7, The above data storage unit includes a first storage space in which the constant data is stored and a second storage space in which the fault / setting data is stored. The above control unit, A high-voltage IGBT gate driver for railway use, which deletes stored data and adds new data in a first-in, first-out manner according to the capacity of the first and second storage spaces.

9. In paragraph 8, The above control unit, A high-voltage IGBT gate driver for railway use, which records the fault / setting data in the second storage space at a time before and after the occurrence of an event condition set by the user through the external device.

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