Marine DC solid-state breaking device

Abstract

A marine DC solid-state disconnect device comprises a controller, a signal acquisition module, a main switch, and a busbar circuit. The busbar circuit includes a port circuit and a starboard circuit. The main switch includes a port switch and a starboard switch. The port switch output is connected to the starboard switch output, the port switch input is connected to the port circuit, and the starboard switch input is connected to the starboard circuit. The signal acquisition module is connected to the busbar circuit and is used to detect electrical signals in the busbar circuit. One end of the controller is connected to the main switch and the other end is connected to the signal acquisition module. The controller determines the location of a fault in the busbar circuit based on the electrical signals sent by the signal acquisition module and controls the port and starboard switches to close or open accordingly. The controller detects the electrical signals in the busbar circuit in real time to accurately detect the fault location and quickly shuts off the corresponding main switch based on the fault location, ensuring the safety of the busbar circuit.

Description

Technical Field

[0001] The present invention relates to the field of direct current technology, and more particularly to a marine direct current solid-state breaking device. Background Art

[0002] The DC system responds very quickly to current changes and can quickly reflect the actual state of the current. It has been widely used in many fields such as power systems, industrial automation, and scientific research. Especially in ship integrated power systems, DC power has been increasingly used due to its advantages such as high efficiency and good performance.

[0003] However, the main problem with DC systems is that they have no natural zero crossing, the impedance of DC lines is low, and DC equipment is sensitive to overcurrent (or overvoltage). Therefore, how to quickly detect circuit faults and quickly and accurately cut off the faults is a key factor in the adaptability of DC systems to ship systems.

[0004] DC systems respond very quickly to current changes, quickly reflecting the actual current state. This is particularly important for control systems requiring fast response times. DC systems can accurately measure a wide range of currents, from milliamperes to hundreds of kiloamperes, meeting the needs of diverse application scenarios. DC systems typically offer excellent isolation, enabling safe measurements in high-voltage and high-current environments, effectively protecting measurement equipment and personnel. Due to their numerous advantages, DC systems have been widely adopted in various fields, including power systems, industrial automation, and scientific research. In particular, DC power systems are increasingly being used in integrated shipboard power systems due to their high efficiency and performance. However, key challenges with DC systems are the lack of a natural zero crossing, the low impedance of DC lines, and the increased sensitivity of DC equipment to overcurrent (or overvoltage). Consequently, DC system protection design presents more challenges than AC systems. Taking a ship's DC system as an example, when a short-circuit fault occurs in the DC system, the current rise rate can reach over 20A / µs, and the peak current can reach over 110kA, making disconnection difficult. If a traditional mechanical circuit breaker is used for protection, specially designed disconnection, arc extinguishing, and contact systems are required to achieve protection. In addition, the large amount of energy stored in the line inductance needs to be released, which will increase the system's withstand voltage and insulation strength.

[0005] Depending on the working conditions, the protective electrical appliances that can be considered include circuit breakers, fuses, load switches, disconnectors and converters. Load switches and disconnectors do not have short-circuit protection functions; DC fuses only have short-circuit protection functions but have long disconnection times and are difficult to maintain; if the power electronic devices of the converter are used for protection, the circuit breaker on the load side can be replaced by a DC disconnector. However, when the converter itself fails or the current limiting fails, a backup short-circuit protection measure is still required between the upper power supply and the converter. When designing the protection of the ship's DC power system, it is necessary to face the challenge that traditional fault detection and protection technologies based on conventional circuit breakers are no longer applicable. On the low-voltage DC side of the ship's integrated power system, a DC circuit breaker is required as a fault protection device for the lower-level inverter. The protection action time is required to be in the millisecond level. If it cannot be disconnected quickly, it will cause the system fault current to rise sharply and the DC bus voltage to drop, affecting the reliable operation of other load devices on the bus. For example Figure 1 As shown, in the case of short circuit on the input side of the subsequent converter, converter failure or current limiting failure, Figure 1 If the F1 or F2 fault cannot be disconnected quickly and reliably, the system fault current will rise sharply and the DC bus voltage will drop, causing other normally operating converters to shut down for protection, seriously affecting the continuity and reliability of power supply.

[0006] In addition, the DC side of the converter is equipped with parallel capacitors for energy storage and wave smoothing, such as Figure 2 and Figure 3 As shown in the figure, when a short circuit occurs, the energy stored in the capacitor will be rapidly released to the short circuit point, and the discharge current can reach thousands to tens of thousands of amperes. As a result, the energy stored in the capacitor and the parallel-connected capacitor used for energy storage and wave smoothing will be quickly released to the short circuit point when a short circuit occurs. The released current can reach thousands to tens of thousands of amperes, causing damage to the capacitor or other equipment and increasing the current intensity at the fault point. In the event of a short circuit, if the DC bus voltage drop is to be maintained within the normal range, the fault must be quickly cleared within a few milliseconds to maintain the DC bus voltage drop within the normal range and allow other equipment on the bus to operate normally. This places high demands on the speed of the DC circuit breaker. Summary of the Invention

[0007] The present invention provides a marine DC solid-state disconnecting device. The disconnecting circuit can accurately determine the fault location in a bus circuit in a short time and quickly disconnect the fault circuit, thereby ensuring the safety and stability of the bus circuit.

[0008] The present invention provides a marine DC solid-state disconnect device, comprising a controller, a signal acquisition module, a main switch, and a bus circuit; wherein the bus circuit comprises a port circuit and a starboard circuit; the main switch comprises a port switch and a starboard switch, wherein the output end of the port switch is connected to the output end of the starboard switch, the input end of the port switch is connected to the port circuit, and the input end of the starboard switch is connected to the starboard circuit; the signal acquisition module is connected to the bus circuit and is used to detect electrical signals in the bus circuit and send the electrical signals to the controller; one end of the controller is connected to the main switch and the other end is connected to the signal acquisition module; the controller determines the location of a fault in the bus circuit based on the electrical signals sent by the signal acquisition module, and controls the port switch and the starboard switch to close and open according to the fault location.

[0009] According to one embodiment of the present invention, the port switch includes a first IGBT module and a second IGBT module, the collector of the first IGBT module is connected to the collector of the second IGBT module and is connected to the bus circuit, and the emitter of the first IGBT module is connected to the emitter of the second IGBT module as the output end of the port switch;

[0010] The starboard switch includes a third IGBT module and a fourth IGBT module. The collector of the third IGBT module is connected to the collector of the fourth IGBT module and is also connected to the bus circuit. The emitter of the third IGBT module is connected to the emitter of the fourth IGBT module as the output end of the starboard switch.

[0011] According to one embodiment of the present invention, it also includes a first freewheeling circuit and a second freewheeling circuit; the first freewheeling circuit includes a first power diode and a first capacitor, the cathode of the first power diode is connected to the output end of the port switch, the anode of the first power diode is connected to the negative electrode of the port circuit, and the first capacitor is connected in parallel between the positive and negative electrodes of the port circuit; the second freewheeling circuit includes a second power diode and a second capacitor, the cathode of the second power diode is connected to the output end of the starboard switch, the anode of the second power diode is connected to the negative electrode of the starboard circuit, and the second capacitor is connected in parallel between the positive and negative electrodes of the starboard circuit. The port switch and the first freewheeling circuit and the starboard switch and the second freewheeling circuit form two step-down circuits connected in anti-series to the marine DC solid-state breaking device.

[0012] According to one embodiment of the present invention, the device further comprises a current-limiting reactor connected between the port switch and the starboard switch.

[0013] According to one embodiment of the present invention, an IGBT driving board is further included. The IGBT driving board is connected between the main switch and the controller and is used to control the main switch according to a control instruction sent by the controller.

[0014] According to one embodiment of the present invention, the signal acquisition module includes a port signal acquisition module and a starboard signal acquisition module; the controller is configured to compare the port electrical signal acquired by the port signal acquisition module and the starboard electrical signal acquired by the starboard signal acquisition module with the normal electrical signal, and control the port switch to be disconnected and / or the starboard switch to be disconnected when the fault location is determined.

[0015] According to one embodiment of the present invention, the port electrical signal is a port current, and the starboard electrical signal is a starboard current; the controller is configured to, when determining that a current rise rate of the port current is greater than a rise rate threshold, determine that the fault location occurs on the port side of the bus circuit, and control the port switch to disconnect; and, when determining that a current rise rate of the starboard current is greater than the rise rate threshold, determine that the fault location occurs on the starboard side of the bus circuit, and control the starboard switch to disconnect.

[0016] According to one embodiment of the present invention, the controller is further configured to, when it is determined that the current amplitude of the port current is greater than a current threshold, determine that the fault location occurs on the port side of the bus circuit, and the controller controls the port switch to disconnect; and, when it is determined that the current amplitude of the starboard current is greater than the current threshold, determine that the fault location occurs on the starboard side of the bus circuit, and the controller controls the starboard switch to disconnect.

[0017] According to one embodiment of the present invention, the signal acquisition module is a Rogowski coil.

[0018] According to one embodiment of the present invention, the port electrical signal is a port voltage, and the starboard electrical signal is a starboard voltage; and the controller is configured to control the port switch and the starboard switch to be disconnected when it is determined that the difference between the port voltage and the starboard voltage is greater than a voltage difference threshold.

[0019] The beneficial effect of the present invention is that the controller detects electrical signals in real time through the signal acquisition module. Once a line fault is detected, the port switch or the starboard switch can be quickly cut off according to the fault location to accurately cut off the fault circuit, avoid burning of electrical appliances connected to the bus circuit, and improve the stability and safety of the bus circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the DC regional power distribution system structure diagram;

[0021] Figure 2 This is a schematic diagram of the short circuit on the input side of the converter;

[0022] Figure 3 is the short-circuit current waveform under rated operating conditions;

[0023] Figure 4 A schematic structural diagram of a marine DC solid-state switching device provided in an embodiment of the present application;

[0024] Figure 5 A schematic diagram of the structure of a main switch provided in an embodiment of the present application;

[0025] Figure 6 A schematic structural diagram of another marine DC solid-state switching device provided in an embodiment of the present application;

[0026] Figure 7 A schematic structural diagram of another marine DC solid-state switching device provided in an embodiment of the present application;

[0027] Figure 8 A schematic diagram of the structure of a signal acquisition module provided in an embodiment of the present application;

[0028] Figure 9 A schematic diagram of a main controller control flow provided in an embodiment of the present application;

[0029] Figure 10 A schematic structural diagram of another signal acquisition module provided in an embodiment of the present application;

[0030] Figure 11 A schematic structural diagram of another signal acquisition module provided in an embodiment of the present application;

[0031] Figure 12 This is a short-circuit protection simulation diagram. DETAILED DESCRIPTION

[0032] The terms and words used in the following description are not limited to the literal meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present invention. Therefore, it will be apparent to those skilled in the art that the following description of various embodiments of the present invention is provided for illustration purposes only and not for the purpose of limiting the present invention as defined by the appended claims and their equivalents.

[0033] Although ordinal numbers such as "first," "second," and the like will be used to describe various components, these are not intended to limit those components. The terms are used solely to distinguish one component from another. For example, a first component could be referred to as a second component, and similarly, a second component could be referred to as a first component without departing from the teachings of the present inventive concept. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0034] The terms used herein are for the purpose of describing various embodiments only and are not intended to be limiting. As used herein, the singular is intended to include the plural, unless the context clearly indicates otherwise. It will also be understood that the terms "comprising" and / or "having" when used in this specification specify the presence of a stated feature, number, step, operation, component, element, or combination thereof, and do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, elements, or groups thereof.

[0035] like Figure 4 FIG. 1 is a structural diagram of a marine DC solid-state switching device 100 provided in an embodiment of the present application. The marine DC solid-state switching device 100 includes a controller 101, a signal acquisition module 102, a main switch 103, and a bus circuit. The main switch 103 includes a port switch 1031 and a starboard switch 1032. The output end of the port switch 1031 is connected to the output end of the starboard switch 1032. The bus circuit includes a port circuit 1041 and a starboard circuit 1042. The input end of the port switch 1031 is connected to the output end of the port circuit 1032. 41. The input end of the starboard switch 1032 is connected to the starboard circuit 1042. The signal acquisition module 102 is connected to the bus circuit and is used to detect the electrical signal of the bus circuit and send the electrical signal to the controller 101. One end of the controller 101 is connected to the main switch 103, and the other end is connected to the signal acquisition module 102. The controller 101 determines the location of the fault in the bus circuit based on the electrical signal sent by the signal acquisition module 102, and controls the closing and opening of the port switch 1031 and the starboard switch 1032 according to the fault location.

[0036] During operation, controller 101 monitors the electrical signals of port circuit 1041 and starboard circuit 1042 in the bus circuit in real time. These signals can reflect the bus circuit's operating status, fault conditions, or conditions requiring circuit breaker disconnection in real time. When controller 101 detects a condition requiring circuit disconnection, such as overcurrent, overvoltage, short circuit, open circuit, or other fault in the bus circuit, it determines whether the electrical signal is occurring in port circuit 1041 or starboard circuit 1042, and disconnects the corresponding port switch 1031 or starboard switch 1032 based on the location. Conversely, once the fault is resolved and the electrical signals of port circuit 1041 and starboard circuit 1042 meet normal conditions, controller 101 can also send a restoration signal to close the main switch, restoring circuit access.

[0037] Under normal operating conditions, the main switch is in a closed state, and current can flow in both directions. The controller 101 can be set locally and directly connected to the main switch. The controller 101 can also remotely control the main switch. Through the shutdown command issued by the controller 101, the port switch 1031 and / or the starboard switch 1032 are turned off, accurately determining the circuit status and fault location, and quickly separating the faulty part from the normal part. Compared with traditional protective electrical appliances, such as circuit breakers, fuses, load switches, disconnectors and converters, it can effectively improve the precise control of circuit faults and quickly cut off the circuit, avoiding the burning of electrical appliances connected to the bus circuit, and improving the stability and safety of the bus circuit.

[0038] like Figure 5 FIG. 1 is a schematic diagram of the structure of the main switch provided in an embodiment of the present application, wherein the port switch includes a first IGBT module Q A1 and the second IGBT module Q A2 , the first IGBT module Q A1 The collector of the second IGBT module Q A2 The collector of the first IGBT module Q is connected to the bus circuit. A1 The emitter of the second IGBT module Q A2 The emitter of the port switch is connected as the output terminal of the port switch; the starboard switch includes a third IGBT module Q A3 and the fourth IGBT module Q A4 , the collector of the third IGBT module QA3 and the collector of the fourth IGBT module Q A4 The collector of the third IGBT module Q A3 The emitter and the fourth IGBT module Q A4 The emitter of is connected as the output of the starboard switch.

[0039] When the current flows from the port side to the starboard side, the voltage of the port circuit 1041 is higher than that of the starboard circuit 1042. The controller 101 turns on the IGBTs in the port switch 1031 and the starboard switch 1032. The current path is that the current flows through the port circuit 1041, Q A1 , Q A4 , starboard circuit 1042. If the IGBT is not turned on, the anti-parallel diode in the IGBT module will turn on to provide a path, and the current path is that the current flows through the port circuit 1041, Q A1 Internal anti-parallel diode, Q A4 Internal anti-parallel diode, starboard circuit 1042.

[0040] When the current flows from starboard to port, the voltage of the starboard circuit 1042 is higher than that of the port circuit 1041, and the controller 101 turns on the IGBTs in the starboard switch 1032 and the port switch 1031. A3 , Q A2 , port circuit 1041. If the IGBT is not conducting, the anti-parallel diode in the IGBT module will conduct to provide a path. The current path is that the current flows through the starboard circuit 1042, Q A3 Anti-parallel diode, Q A2 Internal anti-parallel diode, port circuit 1041.

[0041] The breaking circuit provided in the embodiment of the present application adopts two sets of parallel IGBT modules (Q A1 ~Q A4 ) as the main switch, and then the modules are connected in reverse series to form the main switch of the disconnect circuit. Because it uses IGBT as the main switch, the disconnect circuit has an extremely fast response speed and can achieve circuit disconnection in a very short time.

[0042] like Figure 6 As shown, to improve the stability of the disconnect circuit, an IGBT driver board 105 is included between the main switch and the controller. The IGBT driver board 105 is connected between the main switch 103 and the controller 101 and is used to control the main switch 103 according to control instructions sent by the controller 101. Because both the IGBT driver board and the IGBT main switch are designed with high reliability in mind, the disconnect circuit can ensure stable operation even in harsh operating environments, effectively improving the stability and reliability of the entire system.

[0043] like Figure 7 FIG. 1 is a structural diagram of another marine DC solid-state switching device 100 provided in an embodiment of the present application. Figures 4 to 6 On the basis of, it further includes a freewheeling circuit. The freewheeling circuit specifically includes a first freewheeling circuit and a second freewheeling circuit; wherein, the first freewheeling circuit includes a left power diode D A1 And the first capacitor C1, the port power diode D A1 The cathode of the port switch is connected to the output terminal, and the port power diode D A1 The anode of the port circuit 1041 is connected to the negative electrode, and the first capacitor C1 is connected in parallel between the positive and negative electrodes of the port circuit 1041; the second freewheeling circuit includes the starboard power diode D A2 and the second capacitor C2, the starboard power diode D A2 The cathode of the starboard switch is connected to the output terminal, and the starboard power diode D A2The anode of the capacitor C2 is connected to the negative electrode of the starboard circuit 1042 , and the second capacitor C2 is connected in parallel between the positive electrode and the negative electrode of the starboard circuit 1042 .

[0044] In order to absorb the energy when the main switch is turned off, the power diode D A1 and D A2 Connected in parallel to the inside of the main switch, it establishes a freewheeling loop for the energy of the bus circuit, allowing the current to commutate through this branch, reducing the Q caused by turning off the main switch. A1 ~Q A4 The voltage stress generated can ensure the safety, speed and reliability of circuit breaking.

[0045] Further, continue to refer to Figure 7 As shown, the marine DC solid-state switching device further includes a current-limiting reactor L, which is connected between the port switch 1031 and the starboard switch 1032 .

[0046] The port switch and the first freewheeling circuit form a buck (step-down) circuit, while the starboard switch and the second freewheeling circuit form another buck circuit. These two buck circuits are connected in anti-series to the marine DC solid-state interrupter, effectively improving the DC bus voltage regulation capability. Working together, the two buck circuits enable more precise current diversion and voltage regulation during fault conditions, ensuring that load-side equipment is not damaged by transient current surges.

[0047] Specifically, in the event of a short-circuit fault, the main switch structure described above can rapidly control the current rise rate and reduce the stress caused by the short-circuit current on equipment. The Buck circuit, with its efficient step-down conversion characteristics, not only reduces energy loss but also further improves current transmission efficiency through anti-series connection. The two anti-series Buck circuits effectively control each other during current transmission, ensuring that the short-circuit current does not rise too quickly and reducing voltage shocks to equipment (such as switching elements and power electronics). Furthermore, the anti-series Buck circuits can better regulate the DC bus voltage, ensuring that voltage fluctuations remain within acceptable limits. Even during load changes or short-circuit faults, the system voltage remains stable, effectively protecting load equipment and preventing system instability or equipment damage caused by voltage anomalies.

[0048] At the same time, the two Buck circuits in the anti-series configuration can effectively isolate the load. When a system fault occurs, precise current control can be used to isolate the fault current to a minimum, preventing the fault from spreading to other devices and improving the system's fault tolerance and reliability.

[0049] Buck circuits, as solid-state switches, avoid the mechanical wear and tear of traditional bus tie switches, resulting in a longer service life and higher reliability. The absence of arcing ensures stable operation of the electrical system even under high-frequency use.

[0050] Continue to refer to Figure 7 In the marine DC solid-state disconnect device shown, the signal acquisition module 102 includes a port signal acquisition module and a starboard signal acquisition module; the controller 101 is configured to compare the port electrical signal acquired by the port signal acquisition module and the starboard electrical signal acquired by the starboard signal acquisition module with the normal electrical signal, and control the port switch to be disconnected and / or the starboard switch to be disconnected when the fault location is determined.

[0051] Furthermore, the busbar circuit is equipped with port and starboard disconnectors. These disconnectors connect and disconnect the circuit, maintaining a consistent timing logic with the solid-state main switch. This further ensures that faulty circuits are disconnected, improving the reliability of the busbar circuit system.

[0052] To enhance the busbar circuit's protective effect, the circuit breaker detects electrical signals from both the port and starboard circuits. Combined with high-speed sampling, calculation, and comparison judgment by the controller hardware and processor, the circuit breaker sets a suitable protection threshold. When the electrical signal exceeds the protection threshold, a fault is detected in either the port or starboard circuit, and the faulty circuit is disconnected. Furthermore, the parameters of the current-limiting reactor and capacitor are carefully designed so that the main circuit short-circuit current rises rapidly on the short-circuit side, allowing the current sensor to quickly detect the short-circuit current. On the IGBT-off side, the current rises slowly (relative to the short-circuit), allowing the controller hardware to quickly disconnect the faulty IGBT and reduce the current during IGBT shutdown. This significantly improves fault detection and fault circuit disconnection time, while ensuring busbar circuit safety, thereby enhancing circuit breaker efficiency.

[0053] For DC power supply systems, such as those used in marine DC power systems, a short circuit in any area can affect power supply to other healthy areas if it cannot be quickly shut off. To ensure power supply continuity and reliability, short-circuit detection and fault determination require a response time of tens of microseconds, with no failure or malfunction.

[0054] In order to further shorten the detection time of the fault circuit, such as Figure 8 FIG. 1 is a schematic diagram of a structure of a signal acquisition module provided in an embodiment of the present application, wherein the signal acquisition module 102 includes a port current acquisition module 1021 and a starboard current acquisition module 1022. Based on this, the port electrical signal is the port current, and the starboard electrical signal is the starboard current; based on Figure 8The signal acquisition module shown, the controller 101 can determine the fault location in the bus circuit based on the current signal and perform corresponding control.

[0055] In some examples, the control process of the controller 101 may include: Figure 9 The following steps are shown:

[0056] S801: The controller calculates the current rising rate of the port current and the current rising rate of the starboard current;

[0057] S802: When the current rising rate of the port current is greater than the rising rate threshold, it is determined that the fault location occurs on the port side of the bus circuit, and the controller controls the port side switch to be disconnected;

[0058] S803: When the current rising rate of the starboard current is greater than the rising rate threshold, it is determined that the fault location occurs on the starboard side of the bus circuit, and the controller controls the starboard switch to be disconnected.

[0059] The current rise rate is a physical quantity that describes the speed of current change, representing the amount of current change per unit time. In electrical equipment and systems, the current rise rate is of vital importance, significantly impacting the safety and stability of the equipment. If the current rises too quickly, in some cases, such as in thyristors, it can cause localized overheating and damage the equipment. Therefore, real-time detection of the current rise rate is crucial to ensuring the safe and stable operation of electrical equipment and systems. Specifically, the current rise rate can be calculated by measuring the current change and the time interval. For example, the current rise rate can be calculated by dividing the current change by the time interval.

[0060] In other examples, the control process of the controller 101 may include, when it is determined that the current amplitude of the port current is greater than a current threshold, determining that the fault location occurs on the port side of the bus circuit, and the controller controlling the port switch to disconnect; when it is determined that the current amplitude of the starboard current is greater than the current threshold, determining that the fault location occurs on the starboard side of the bus circuit, and the controller controlling the starboard switch to disconnect.

[0061] In some other examples, the control process of the controller 101 can also adopt a dual judgment rule, that is, while judging the current rise rate, it also judges the current amplitude. By monitoring the current rise rate and amplitude in real time, the system can quickly determine the type and severity of the short circuit. The current rise rate can reflect the speed at which the short circuit occurs, and the amplitude can provide information on the intensity of the short-circuit current. Combining these two parameters, the type and nature of the short-circuit event can be more accurately determined, thereby avoiding the misjudgment and delay that may be caused by the traditional single judgment method.

[0062] Traditional protection systems can misjudge when current peaks reach a certain threshold, leading to untimely circuit breaker activation or over-protection. However, by combining both the rate of rise and the amplitude for dual determination, false trips caused by current fluctuations can be effectively prevented, ensuring the system responds accurately to short circuits. Furthermore, the system can quickly detect current changes as soon as the short-circuit current begins to rise, determining whether protective measures are necessary. By using the short-circuit rise rate, the system can very quickly identify short-circuit faults with high rise rates, reducing protection delays.

[0063] Real-time monitoring of the short-circuit rise rate allows the system to react as the current begins to rise, preventing failure to operate due to delays in detection before the short-circuit current reaches its limit. Through accurate detection, the system can promptly disconnect the fault circuit and prevent the fault from spreading.

[0064] In some examples, the signal acquisition module is a Rogowski coil. Rogowski coils provide high-precision current waveform capture and fast response, enabling accurate measurement of high-frequency signals and sudden currents. They are particularly suitable for rapidly changing currents, such as short-circuit current detection. Furthermore, Rogowski coils can accurately capture the current waveform during capacitor discharge, enabling timely identification of its impact on the system, helping to further improve the response speed and accuracy of short-circuit protection.

[0065] like Figure 10 FIG. 1 is a schematic diagram of the structure of another signal acquisition module provided in an embodiment of the present application, wherein the signal acquisition module 102 includes a port voltage acquisition module 1023 and a starboard voltage acquisition module 1024. Based on this, the port electrical signal is the port voltage, and the starboard electrical signal is the starboard voltage; based on Figure 8 In the signal acquisition module shown, the controller 101 can control the port switch and the starboard switch to be disconnected when it is determined that the difference between the port voltage and the starboard voltage is greater than the voltage difference threshold.

[0066] In order to more reasonably judge the fault type and fault location in the bus circuit, the signal acquisition module can include both the current acquisition module and the voltage acquisition module, such as Figure 11 As shown, the signal acquisition module simultaneously collects current signals and voltage signals and transmits them to the controller. The controller calculates and compares and judges, and uses the judgment conditions such as the current exceeding the current threshold and the voltage difference between the two ends being higher than the voltage difference threshold as the basis for fault protection. At the same time, the parameters of the current limiting inductor and capacitor are reasonably designed so that the short-circuit current rise rate of the main circuit rises rapidly on the short-circuit side, and the short-circuit current is quickly detected by the current sensor; while the circuit on the IGBT shutdown side rises slowly (relative to the short circuit), and the controller hardware cooperates to quickly cut off the fault IGBT, reducing the current when the IGBT is turned off.

[0067] like Figure 12As shown in the figure, it is a short circuit protection simulation diagram. Figure 11 The short-circuit current rise rate of the system shown is relatively fast (greater than 60A / us), and the short-circuit current rise rate needs to be limited. The energy stored in the line inductance needs to be properly dissipated to protect the power electronic devices from overvoltage damage.

[0068] Experiments have proven that the marine DC solid-state disconnect device provided in the embodiments of the present application uses a hardware circuit to detect the current value of the main circuit. When the protection threshold is reached, a trip signal is output with a delay of 2-3 μs. The judgment value is transmitted to the controller (FPGA) with a delay of less than 1 μs. After receiving the trigger signal, the FPGA immediately executes the trip command with a delay of 2-3 μs. After receiving the trip command, the IGBT driver board executes the trip action and shuts down the IGBT in less than 10 μs. In summary, the time required for the entire process meets the 20 μs cut-off time requirement. This meets the requirement for rapid detection of faulty circuits in a short period of time, improving the reliability of the entire circuit system.

[0069] While the basic principles of the present invention have been described above in conjunction with specific embodiments, it should be noted that the advantages, strengths, and effects mentioned herein are merely illustrative and non-restrictive, and should not be construed as necessarily possessed by each embodiment of the present invention. Furthermore, the specific details disclosed above are provided for illustrative purposes and to facilitate understanding, and are not intended to be limiting. These details do not necessarily limit the present invention to being implemented using these specific details.

[0070] The block diagrams of the devices, apparatuses, equipment, and systems involved in the present invention are intended to be illustrative examples only and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems may be connected, arranged, or configured in any manner. Words such as "include," "comprise," "have," and the like are open-ended words that mean "including but not limited to," and may be used interchangeably therewith. The words "or," "and," and "as used herein refer to the words "and / or," and may be used interchangeably therewith, unless the context clearly indicates otherwise. The word "such as," as used herein, refers to the phrase "such as, but not limited to," and may be used interchangeably therewith.

[0071] It should also be noted that in the apparatus, device and method of the present invention, each component or each step can be decomposed and / or recombined, and such decomposition and / or recombination should be regarded as equivalent solutions of the present invention.

[0072] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present invention. Therefore, the present invention is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0073] The above description has been provided for the purpose of illustration and description. Furthermore, this description is not intended to limit the embodiments of the present invention to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A marine DC solid-state breaking device, characterized in that: It includes a controller, a signal acquisition module, a main switch and a bus circuit; wherein, The busbar circuit includes a port circuit and a starboard circuit; The main switch includes a port switch and a starboard switch, wherein the output end of the port switch is connected to the output end of the starboard switch, the input end of the port switch is connected to the port circuit, and the input end of the starboard switch is connected to the starboard circuit; The signal acquisition module is connected to the bus circuit, and is used to detect the electrical signal in the bus circuit and send the electrical signal to the controller; One end of the controller is connected to the main switch, and the other end is connected to the signal acquisition module. The controller determines the location of the fault in the bus circuit according to the electrical signal sent by the signal acquisition module, and controls the port switch and the starboard switch to be closed or disconnected according to the fault location. Also includes a first freewheeling circuit and a second freewheeling circuit; The port switch and the first freewheeling circuit and the starboard switch and the second freewheeling circuit form two step-down circuits connected in anti-series to the marine DC solid-state switching device; The signal acquisition module includes a port signal acquisition module and a starboard signal acquisition module, and the controller is configured to compare the port electrical signal acquired by the port signal acquisition module and the starboard electrical signal acquired by the starboard signal acquisition module with the normal electrical signal, and control the port switch to be disconnected and / or the starboard switch to be disconnected when the fault location is determined; The port electrical signal is the port current, and the starboard electrical signal is the starboard current; The first freewheeling circuit includes a first power diode and a first capacitor, wherein the cathode of the first power diode is connected to the output end of the port switch, the anode of the first power diode is connected to the negative electrode of the port circuit, and the first capacitor is connected in parallel between the positive and negative electrodes of the port circuit; The second freewheeling circuit includes a second power diode and a second capacitor, the cathode of the second power diode is connected to the output end of the starboard switch, the anode of the second power diode is connected to the negative electrode of the starboard circuit, and the second capacitor is connected in parallel between the positive and negative electrodes of the starboard circuit.

2. The marine DC solid-state breaking device according to claim 1, characterized in that: The invention also includes a current-limiting reactor connected between the port switch and the starboard switch; wherein the port switch includes a first IGBT module and a second IGBT module, the collector of the first IGBT module is connected to the collector of the second IGBT module and is connected to the bus circuit, and the emitter of the first IGBT module is connected to the emitter of the second IGBT module as the output end of the port switch; the starboard switch includes a third IGBT module and a fourth IGBT module, the collector of the third IGBT module is connected to the collector of the fourth IGBT module and is connected to the bus circuit, and the emitter of the third IGBT module is connected to the emitter of the fourth IGBT module as the output end of the starboard switch.

3. The marine DC solid-state breaking device according to any one of claims 1 to 2, characterized in that: It also includes an IGBT driving board, which is connected between the main switch and the controller and is used to control the main switch according to a control instruction sent by the controller.

4. The marine DC solid-state breaking device according to claim 1, characterized in that: The controller is configured to, when determining that the current rise rate of the port current is greater than a rise rate threshold, determine that the fault location occurs on the port side of the bus circuit, and control the port switch to disconnect; and, when determining that the current rise rate of the starboard current is greater than the rise rate threshold, determine that the fault location occurs on the starboard side of the bus circuit, and control the starboard switch to disconnect.

5. The marine DC solid-state breaking device according to claim 4, characterized in that: The controller is further configured to, when it is determined that the current amplitude of the port current is greater than a current threshold, determine that the fault location occurs on the port side of the bus circuit, and control the port switch to open; and, when it is determined that the current amplitude of the starboard current is greater than the current threshold, determine that the fault location occurs on the starboard side of the bus circuit, and control the starboard switch to open.

6. The marine DC solid-state breaking device according to claim 1, characterized in that: The signal acquisition module is a Rogowski coil.

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