Solid-state direct-current circuit breaker based on three-winding coupling inductor and control method thereof

Abstract

The invention relates to the technical field of circuit breakers, and discloses a solid-state direct-current circuit breaker based on a three-winding coupling inductor and a control method of the solid-state direct-current circuit breaker. According to the connection relation of an energy consumption branch circuit, a through-flow branch circuit, a left side charging branch circuit, a right side charging branch circuit, a capacitor branch circuit, a capacitor charging resistor branch circuit, a first coupling inductor branch circuit and a second coupling inductor branch circuit; power is directly taken from a system line through the charging branch and the capacitor charging resistor branch, and an additional charging power supply does not need to be configured, so that the operation difficulty and the maintenance cost are reduced. Through the reasonable design of the circuit, the problem of unreliable on-off caused by unknown fault distance and parameters can be effectively avoided, a conduction impedance path in a through-flow branch is reduced, the operation energy consumption is reduced, the efficiency of the system is improved, after the current on-off is finished, a charging loop of the capacitor is not influenced and can be quickly recovered to an initial state, and the service life of the capacitor is prolonged. And the adaptability and the operation safety of the system under complex working conditions are enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit breakers, and in particular to a solid-state DC circuit breaker based on three-winding coupled inductance and a control method thereof. Background Art

[0002] In DC power systems, system protection is the core link to ensure its safety and reliability. Especially in modern application scenarios such as energy storage equipment, photovoltaic power generation, wind power generation, and electric vehicle charging stations, DC system protection is particularly important.

[0003] Compared with traditional AC systems, the dynamic characteristics of short-circuit faults in DC systems are significantly different, which is manifested in that the short-circuit current rises faster and has a larger amplitude. This characteristic not only poses a serious threat to the DC system itself, but may also damage key equipment in the system, causing overall system instability. Therefore, a fast and effective DC protection mechanism has become an important technical challenge in the design of DC power systems.

[0004] As the core equipment for DC system protection, DC circuit breakers can quickly and accurately detect and interrupt fault current when a fault occurs, preventing the fault from further spreading. This function can not only effectively avoid overcurrent damage to equipment, but also enhance the stability and reliability of the system, thereby improving the overall operating efficiency of the power system. Therefore, DC circuit breakers have become one of the hot topics in the field of power engineering research in recent years, and have received extensive attention and in-depth exploration.

[0005] Among them, solid-state DC circuit breakers have attracted much attention due to their design based on solid-state switching devices. Compared with traditional mechanical circuit breaker solutions, solid-state DC circuit breakers have significant advantages in breaking speed and operating accuracy, and are especially suitable for the high demand for fast protection in DC systems. Further analysis shows that compared with fully controlled switching devices, the application of semi-controlled devices such as thyristors in solid-state DC circuit breakers presents many advantages, including low on-resistance, mature manufacturing process, lower procurement cost and excellent surge current tolerance. These advantages have enabled the thyristor-based DC circuit breaker topology to develop significantly in recent years and have attracted widespread attention in academia and industry.

[0006] Nevertheless, existing thyristor-based solid-state DC circuit breaker designs still have the following limitations and challenges:

[0007] 1) Insufficient controllability: Passive thyristor solid-state DC circuit breakers can only act passively after a fault occurs and cannot actively interrupt the current when the system is operating normally, thus limiting its application potential in precise control.

[0008] 2) Risk of false triggering: Load changes may cause line current fluctuations. These fluctuation characteristics are similar to fault characteristics in some cases, which may trigger false operation of passive solutions, causing the system to shut down incorrectly and affecting power supply reliability.

[0009] 3) Increased current stress: During the fault current interruption process, the external line current will continue to rise, causing other power electronic devices in the DC system to face higher current stress, which may shorten the equipment life.

[0010] 4) Low efficiency: The operating current usually needs to pass through multiple power electronic devices in the current branch. The on-resistance of these devices is large, resulting in high energy loss and affecting system efficiency.

[0011] 5) Lack of reclosing function: After the fault is first interrupted, a reclosing operation is usually required to determine whether the fault still exists. However, some existing designs lack reliable reclosing protection functions, which limits their practical application scenarios.

[0012] 6) Insufficient reliability of the turn-off process: The turn-off circuit of the thyristor usually depends on external circuit parameters. This dependence may lead to reduced reliability in the current interruption process, especially in the case of parameter deviation or changes in environmental conditions. Summary of the invention

[0013] In view of this, in order to solve the above technical problems, the present invention provides a solid-state DC circuit breaker based on a three-winding coupled inductor and a control method thereof.

[0014] The first aspect of the present invention provides a solid-state DC circuit breaker based on a three-winding coupled inductor, comprising: an energy consumption branch 10, a current flow branch 20, a left charging branch 31, a right charging branch 32, a capacitor branch 40, a capacitor charging resistor branch 50, a first coupled inductor branch 60 and a second coupled inductor branch 70;

[0015] The energy consumption branch 10 is connected in parallel with the flow branch 20;

[0016] The two ends of the through-current branch 20 are electrically connected to the left charging branch 31 and the right charging branch 32 respectively;

[0017] One end of the left charging branch 31 away from the current-passing branch 20 and one end of the right charging branch 32 away from the current-passing branch 20 are connected to the first coupled inductor branch 60 and the second coupled inductor branch 70 respectively;

[0018] The first coupled inductor branch 60, the second coupled inductor branch 70 and the capacitor branch 40 are connected in parallel;

[0019] A first end of the capacitor charging resistor branch 50 is electrically connected to the first coupled inductor branch 60 , the second coupled inductor branch 70 and the capacitor branch 40 , respectively, and a second end of the capacitor charging resistor branch 50 is grounded.

[0020] Preferably, the energy consumption branch 10 includes a lightning arrester M m .

[0021] Preferably, the current-passing branch 20 includes a thyristor T1, a thyristor T2 and a tertiary winding N3;

[0022] The thyristor T1 and the thyristor T2 are connected in reverse parallel;

[0023] The thyristor T1 is connected to the tertiary winding N3 .

[0024] Preferably, the left charging branch 31 includes a diode D L , the diode D L The anode of the diode D is electrically connected to the current branch 20. L The cathode is electrically connected to the first coupled inductor branch 60.

[0025] Preferably, the right charging branch 32 includes a diode D R , the diode D R The anode of the diode D is electrically connected to the current branch 20. R The cathode of the diode D L The cathode of is electrically connected to the second coupled inductor branch 70.

[0026] Preferably, the capacitor branch 40 includes a capacitor C, a diode D C and arrester M C ;

[0027] The first end of the capacitor C is connected to the connection point of the left charging branch 31 and the right charging branch 32, and the second end of the capacitor C is connected to the first end of the capacitor charging resistor branch 50;

[0028] The diode D C The anode of the arrester M C The first end of the diode D is electrically connected to C The cathode is connected to the connection point of the left charging branch 31 and the right charging branch 32;

[0029] The arrester M C The second end of is connected to the connection point of the capacitor C and the capacitor charging resistance branch 50.

[0030] Preferably, the capacitor charging resistor branch 50 includes a resistor R C The resistor R C The first end of the resistor R is electrically connected to the first coupled inductor branch 60, the second coupled inductor branch 70 and the capacitor branch 40 respectively. C The second end is grounded.

[0031] Preferably, the first coupled inductor branch 60 includes a primary winding N1 and a thyristor T N1 ;

[0032] The first end of the primary winding N1 is electrically connected to the left charging branch 31, and the second end of the primary winding N1 is electrically connected to the thyristor T N1 Anode connection;

[0033] The thyristor T N1 The cathode is connected to the connection point of the capacitor branch 40 and the capacitor charging resistor branch 50.

[0034] Preferably, the second coupled inductor branch 70 includes a secondary winding N2 and a thyristor T N2 ;

[0035] The first end of the secondary winding N2 is electrically connected to the right charging branch 32, and the second end of the secondary winding N2 is electrically connected to the thyristor T N2 Anode connection;

[0036] The thyristor T N2 The cathode is connected to the connection point of the capacitor branch 40 and the capacitor charging resistor branch 50.

[0037] In a second aspect, the present invention further provides a control method for a solid-state DC circuit breaker based on a three-winding coupled inductor as described in the first aspect, comprising the following steps:

[0038] When the branch to be charged is fully charged through the left charging branch or the right charging branch, it is determined whether the DC system starts to start;

[0039] When it is determined that the DC system starts to start, a conduction signal is generated and sent to the flow branch, and it is determined whether the current of the flow branch passes through zero during normal operation;

[0040] When it is determined that the current of the through-flow branch does not pass zero during normal operation, it is determined whether the through-flow branch receives a current disconnection signal from a DC system; when it is determined that the current of the through-flow branch passes zero during normal operation, the process proceeds to the step of generating a conduction signal, sending the signal to the through-flow branch, and determining whether the current of the through-flow branch passes zero during normal operation;

[0041] When it is determined that the flow branch has not received the current disconnection signal of the DC system, the step of determining whether the current of the flow branch passes through zero during normal operation is performed;

[0042] When it is determined that the through-current branch receives the current disconnection signal of the DC system, it is determined whether the current flow direction of the through-current branch flows from the left charging branch direction to the right charging branch direction;

[0043] When it is determined that the current flow direction of the current-passing branch is from the left charging branch to the right charging branch, the first coupled inductor branch is turned on;

[0044] When it is determined that the current flow direction of the current-passing branch is not from the left charging branch to the right charging branch, the second coupled inductor branch is turned on;

[0045] Determining whether the DC system needs reclosing;

[0046] When it is determined that the DC system needs to be reclosed, the process proceeds to the step of determining whether the DC system starts to start after the branch to be charged is fully charged via the left charging branch or the right charging branch;

[0047] When it is determined that the DC system does not require reclosing, the process ends.

[0048] It can be seen from the above technical solutions that the embodiment of the present application directly draws power from the system line through the connection relationship between the energy consumption branch, the flow branch, the left charging branch, the right charging branch, the capacitor branch, the capacitor charging resistor branch, the first coupled inductor branch and the second coupled inductor branch, and does not need to configure an additional charging power supply, which not only reduces the hardware cost of the system, but also simplifies the installation and debugging process, thereby reducing the difficulty of operation and maintenance costs. Through the reasonable design of the circuit, the unreliable disconnection problem caused by the unknown fault distance and parameters can be effectively avoided, the reliability of fault current disconnection can be significantly improved, and the on-resistance path in the flow branch can be reduced, the operating energy consumption can be reduced, and the efficiency of the system can be improved. After the current is disconnected, the charging circuit of the capacitor is not affected and can be quickly restored to the initial state, which enhances the adaptability and operation safety of the system under complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0050] Figure 1 A schematic structural diagram of a solid-state DC circuit breaker based on a three-winding coupled inductor provided in an embodiment of the present invention;

[0051] Figure 2 A flow chart of a control method for a solid-state DC circuit breaker based on a three-winding coupled inductor provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] like Figure 1 As shown, the embodiment of the present application provides a solid-state DC circuit breaker based on a three-winding coupled inductor, including: an energy consumption branch 10, a current flow branch 20, a left charging branch 31, a right charging branch 32, a capacitor branch 40, a capacitor charging resistor branch 50, a first coupled inductor branch 60, and a second coupled inductor branch 70;

[0054] The energy consumption branch 10 is connected in parallel with the flow branch 20;

[0055] The two ends of the through-current branch 20 are electrically connected to the left charging branch 31 and the right charging branch 32 respectively;

[0056] One end of the left charging branch 31 away from the current-passing branch 20 and one end of the right charging branch 32 away from the current-passing branch 20 are connected to the first coupled inductor branch 60 and the second coupled inductor branch 70 respectively;

[0057] The first coupled inductor branch 60, the second coupled inductor branch 70 and the capacitor branch 40 are connected in parallel;

[0058] A first end of the capacitor charging resistor branch 50 is electrically connected to the first coupled inductor branch 60 , the second coupled inductor branch 70 and the capacitor branch 40 , respectively, and a second end of the capacitor charging resistor branch 50 is grounded.

[0059] It should be noted that the embodiment of the present application directly draws power from the system line through the connection relationship between the energy consumption branch, the flow branch, the left charging branch, the right charging branch, the capacitor branch, the capacitor charging resistor branch, the first coupled inductor branch and the second coupled inductor branch, and does not need to configure an additional charging power supply, which not only reduces the hardware cost of the system, but also simplifies the installation and debugging process, thereby reducing the difficulty of operation and maintenance costs. Through the reasonable design of the circuit, the unreliable disconnection problem caused by the unknown fault distance and parameters can be effectively avoided, the reliability of the fault current disconnection can be significantly improved, and the on-resistance path in the flow branch can be reduced, the operating energy consumption can be reduced, and the efficiency of the system can be improved. After the current is disconnected, the charging circuit of the capacitor is not affected and can be quickly restored to the initial state, which enhances the adaptability and operation safety of the system under complex working conditions.

[0060] In some embodiments, the energy consumption branch 10 includes a lightning arrester M m .

[0061] In some embodiments, the current-passing branch includes a thyristor T1, a thyristor T2, and a tertiary winding N3;

[0062] Thyristor T1 and thyristor T2 are connected in reverse parallel;

[0063] The thyristor T1 is connected to the tertiary winding N3.

[0064] Among them, the current branch is located at the positive pole of the DC system, one side is the left side, and the other side is the right side. From left to right, it passes through the reverse parallel thyristor T1 and thyristor T2 and the tertiary winding N3 of the coupled inductor in turn, among which the a3 end of the tertiary winding N3 is connected first and then the b3 end of the tertiary winding N3 is connected.

[0065] In some embodiments, the left charging branch includes a diode D L , diode D L The anode of the diode D is electrically connected to the current branch. L The cathode is electrically connected to the first coupled inductor branch.

[0066] In some embodiments, the right charging branch includes a diode D R , diode D R The anode of the diode D is electrically connected to the current branch. R The cathode of diode D L The cathode of the second coupled inductor branch is electrically connected.

[0067] In some embodiments, the capacitor branch includes a capacitor C, a diode D C and arrester M C ;

[0068] A first end of the capacitor C is connected to a connection point of the left charging branch and the right charging branch, and a second end of the capacitor C is connected to a first end of the capacitor charging resistor branch;

[0069] Diode D C Anode and arrester M C The first end of the diode D is electrically connected to C The cathode is connected to the connection point of the left charging branch and the right charging branch;

[0070] Lightning arrester M C The second end of is connected to the connection point of the capacitor C and the capacitor charging resistance branch.

[0071] In some embodiments, the capacitor charging resistor branch includes a resistor R C ; Resistance R C The first end of the resistor R is electrically connected to the first coupled inductor branch, the second coupled inductor branch and the capacitor branch respectively. C The second end is grounded.

[0072] In some embodiments, the first coupled inductor branch includes a primary winding N1 and a thyristor T N1 ;

[0073] The first end of the primary winding N1 is electrically connected to the left charging branch, and the second end of the primary winding N1 is electrically connected to the thyristor T N1 Anode connection;

[0074] Thyristor N1 The cathode is connected to the connection point of the capacitor branch and the capacitor charging resistor branch.

[0075] In some embodiments, the second coupled inductor branch includes a secondary winding N2 and a thyristor T N2 ;

[0076] The first end of the secondary winding N2 is electrically connected to the right charging branch, and the second end of the secondary winding N2 is electrically connected to the thyristor T N2 Anode connection;

[0077] Thyristor N2 The cathode is connected to the connection point of the capacitor branch and the capacitor charging resistor branch.

[0078] It should be noted that in the above embodiment, the winding N 1~3 a 1~3 For the same-name end, winding N 1~3 b 1~3 It is the end with the same name.

[0079] It can be understood that the circuit design of the solid-state DC circuit breaker based on the three-winding coupled inductor provided in the embodiment of the present application has the following advantages.

[0080] 1) Significant cost advantage: The present invention uses low-cost semi-controlled thyristors as core switching elements, which significantly reduces the overall manufacturing cost of the system compared to the traditional DC circuit breaker solution based on fully controlled switching devices. While ensuring performance, this design improves the economy of the solution and provides feasibility and market competitiveness for the large-scale promotion and application of DC circuit breakers.

[0081] 2) No need for additional charging power supply: The present invention directly draws power from the circuit through the left / right charging branch and the capacitor charging resistor branch, without the need for an additional independent charging power supply. This design effectively simplifies the system structure and reduces the need for additional hardware, thereby further reducing material costs. At the same time, this design method greatly reduces the complexity of installation and debugging, simplifies the operation process, and significantly improves the ease of use and maintenance of the system.

[0082] 3) High disconnection reliability: When a fault occurs, since the diodes in the left / right charging branches have unidirectional conduction characteristics, capacitor C will not release stored energy through the fault point, and its voltage remains stable throughout the entire fault handling process. This feature effectively avoids the adverse effects of capacitor voltage fluctuations and ensures the continuous stability of the capacitor state, thereby significantly improving the reliability and repeatability of the disconnection process, and can reliably complete fault isolation and protection operations even under complex working conditions.

[0083] 4) High-efficiency operation: Under normal system operation, the current in the flow branch only needs to pass through a single thyristor and winding N3, rather than the path of multiple switching devices in the traditional design. This design greatly reduces the on-resistance path, fundamentally reduces power loss, and significantly improves operating efficiency. Not only that, the optimization scheme also enhances the long-term performance stability of the system, while reducing operating energy consumption, providing an effective solution for building an energy-saving DC power system.

[0084] 5) Support reclosing protection: Regardless of whether a fault occurs on the left or right side, the capacitor can quickly recover to its initial state after the fault is handled, providing the necessary energy reserve for subsequent reclosing operations. This design enables the present invention to have a strong fault breaking capability while also supporting repetitive protection functions, greatly expanding the applicability of application scenarios and significantly improving the operating safety and stability of the DC system.

[0085] like Figure 2 As shown, the embodiment of the present application also provides a control method of a solid-state DC circuit breaker based on a three-winding coupled inductor as in the above embodiment, comprising the following steps:

[0086] Step S1: When the branch to be charged is fully charged via the left charging branch or the right charging branch, it is determined whether the DC system starts to start.

[0087] The branch to be charged is charged via line-left / right charging branch-capacitor branch-capacitor charging resistor branch-ground.

[0088] Step S2: when it is determined that the DC system starts to start, a conduction signal is generated and sent to the flow branch, and it is determined whether the current of the flow branch passes through zero during normal operation.

[0089] When it is determined that the DC system has not started, the process goes to step S1. When it is determined that the DC system has started, a conduction signal is generated and sent to the thyristor T1 and the thyristor T2 in the current-carrying branch to conduct.

[0090] Step S3: when it is determined that the current of the flow branch does not pass through zero during normal operation, it is determined whether the flow branch receives a current disconnection signal from the DC system; when it is determined that the current of the flow branch passes through zero during normal operation, the process proceeds to the step of generating a conduction signal and sending it to the flow branch, and determining whether the current of the flow branch passes through zero during normal operation.

[0091] Step S4: when it is determined that the flow branch has not received the current interruption signal of the DC system, the process proceeds to the step of determining whether the current of the flow branch passes through zero during normal operation.

[0092] Step S5: when it is determined that the flow branch receives the current interruption signal of the DC system, it is determined whether the current flow direction of the flow branch flows from the left charging branch to the right charging branch.

[0093] Step S6: When it is determined that the current flow direction of the current-carrying branch is from the left charging branch to the right charging branch, the first coupled inductor branch is turned on.

[0094] Step S7: when it is determined that the current flow direction of the current-carrying branch is not from the left charging branch to the right charging branch, the second coupled inductor branch is turned on.

[0095] Step S8: Determine whether the DC system needs reclosing.

[0096] Step S9: When it is determined that the DC system needs to be reclosed, the process proceeds to the step of determining whether the DC system starts to start after the branch to be charged is fully charged via the left charging branch or the right charging branch.

[0097] Step S10: When it is determined that the DC system does not need reclosing, the process ends.

[0098] It should be noted that steps S1 to S7 are the system startup and current interruption process. If reclosing is required, the process proceeds to step S8.

[0099] In the embodiment of the present application, it is necessary to ensure that the reverse recovery process of each thyristor is long enough through reasonable parameter design, so as to achieve a reliable shutdown function.

[0100] In the embodiment of the present application, the coupled inductor is designed to ensure that the stress generated inside the circuit breaker is kept within a controllable range, thereby avoiding excessive electrical stress on the equipment and ensuring the stability and reliability of the system.

[0101] In the embodiments of the present application, the current carrying capacity of each device is evaluated, especially in the case of current surge, to ensure that the device can withstand sudden current fluctuations, thereby preventing the surge current from causing damage or failure to the device.

[0102] The control method of the solid-state DC circuit breaker based on the three-winding coupled inductor provided in the embodiment of the present application is different from the passive scheme that uses the fault itself as the trigger condition. The embodiment of the present application adopts an active control strategy, which can actively interrupt the current during the operation of the system without relying on the occurrence of the fault itself. This active control method enables the circuit breaker to respond accurately according to the operating conditions detected in real time, thereby significantly improving the flexibility and reliability of control. Compared with the passive scheme, the present invention has stronger controllability and can effectively avoid damage to the equipment caused by fault expansion or current shock, ensuring the stability and safety of the system.

[0103] The embodiments of the present application can accurately judge the current change during the process of load switching and system current fluctuation, and will not cause false triggering due to current fluctuation or waveform characteristics similar to the fault. This feature enables the present invention to adapt to more complex working conditions, avoid misoperation or unnecessary actions, and thus ensure the stable operation of the system under different working environments. Compared with the traditional solution based on the fault itself triggering, the present invention has higher robustness and reliability when facing dynamic changes in the system.

[0104] In the design of the embodiment of the present application, the combined effect of the coupling inductor and the charging capacitor is utilized. After a successful action, the arrester in the energy consumption branch will act in time to clamp the voltage across the circuit breaker to a level higher than the system voltage. This process effectively and quickly suppresses the rise of line current, avoids the expansion of excessive current, and thus reduces the harm of the fault to the DC system. Through this design, the system can not only respond quickly when a fault occurs, but also provide stronger protection capabilities, thereby ensuring the stability and safety of the DC system in various fault scenarios.

[0105] In the embodiment of the present application, when the operating current or the fault current is disconnected, a unified control method is adopted, that is, control is performed by turning on the thyristor in the coupled inductor branch. This design simplifies the control steps, making the operation process of the entire circuit breaker simpler and more intuitive, and reducing the complexity and potential errors in the operation process. Due to the consistency of the control method, in the embodiment of the present application, the stability and efficiency of the disconnection process can be guaranteed under various operating conditions.

[0106] In the embodiment of the present application, the thyristor shutdown process in the current branch is independent of the external circuit and independently completes the current breaking task. Since the shutdown process does not depend on the external circuit parameters, the reliability of current breaking can be ensured, and the problem of breaking failure that may be caused by external circuit changes can be avoided. This design improves the autonomy and stability of the circuit breaker, enabling it to effectively perform breaking operations in complex electrical environments, thereby improving the overall reliability and safety of the DC system.

[0107] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0108] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A solid-state DC circuit breaker based on a three-winding coupled inductor, characterized in that: include: An energy consumption branch (10), a current flow branch (20), a left charging branch (31), a right charging branch (32), a capacitor branch (40), a capacitor charging resistor branch (50), a first coupled inductor branch (60), and a second coupled inductor branch (70); The energy consumption branch (10) is connected in parallel with the flow branch (20); Two ends of the through-current branch (20) are electrically connected to the left charging branch (31) and the right charging branch (32) respectively; An end of the left charging branch (31) away from the current-passing branch (20) and an end of the right charging branch (32) away from the current-passing branch (20) are respectively connected to the first coupled inductor branch (60) and the second coupled inductor branch (70); The first coupled inductor branch (60), the second coupled inductor branch (70), and the capacitor branch (40) are connected in parallel; The first end of the capacitor charging resistor branch (50) is electrically connected to the first coupled inductor branch (60), the second coupled inductor branch (70) and the capacitor branch (40) respectively, and the second end of the capacitor charging resistor branch (50) is grounded.

2. The solid-state DC circuit breaker based on three-winding coupled inductance according to claim 1, characterized in that: The energy consumption branch (10) includes a lightning arrester (M m ).

3. The solid-state DC circuit breaker based on three-winding coupled inductance according to claim 1, characterized in that: The current-passing branch (20) comprises a thyristor (T1), a thyristor (T2) and a tertiary winding (N3); The thyristor (T1) and the thyristor (T2) are connected in reverse parallel; The thyristor (T1) is connected to the tertiary winding (N3).

4. The solid-state DC circuit breaker based on three-winding coupled inductor according to claim 1, characterized in that: The left charging branch (31) includes a diode (D L ), the diode (D L ) is electrically connected to the current branch (20), and the diode (D L ) has a cathode electrically connected to the first coupled inductor branch (60).

5. The solid-state DC circuit breaker based on three-winding coupled inductance according to claim 4, characterized in that: The right charging branch (32) includes a diode (D R ), the diode (D R ) is electrically connected to the current branch (20), and the diode (D R ) are connected to the cathode of the diode (D L ) is electrically connected to the cathode of the second coupled inductor branch (70).

6. The solid-state DC circuit breaker based on three-winding coupled inductance according to claim 1, characterized in that: The capacitor branch (40) comprises a capacitor (C), a diode (D C ) and lightning arrester (M C ); The first end of the capacitor (C) is connected to the connection point of the left charging branch (31) and the right charging branch (32), and the second end of the capacitor (C) is connected to the first end of the capacitor charging resistor branch (50); The diode (D C ) of the anode and the arrester (M C ) is electrically connected to the first end of the diode (D C ) has a cathode connected to a connection point between the left charging branch (31) and the right charging branch (32); The arrester (M C ) is connected to the connection point of the capacitor (C) and the capacitor charging resistance branch (50).

7. The solid-state DC circuit breaker based on three-winding coupled inductance according to claim 1 or 6, characterized in that: The capacitor charging resistor branch (50) includes a resistor (R C ); the resistance (R C ) are respectively electrically connected to the first coupled inductor branch (60), the second coupled inductor branch (70) and the capacitor branch (40), and the resistor (R C ) is grounded.

8. The solid-state DC circuit breaker based on three-winding coupled inductor according to claim 1, characterized in that: The first coupled inductor branch (60) comprises a primary winding (N1) and a thyristor (T N1 ); The first end of the primary winding (N1) is electrically connected to the left charging branch (31), and the second end of the primary winding (N1) is electrically connected to the thyristor (T N1 )’s anode connection; The thyristor (T N1 ) is connected to the connection point of the capacitor branch (40) and the capacitor charging resistor branch (50).

9. The solid-state DC circuit breaker based on three-winding coupled inductor according to claim 1, characterized in that: The second coupled inductor branch (70) comprises a secondary winding (N2) and a thyristor (T N2 ); The first end of the secondary winding (N2) is electrically connected to the right charging branch (32), and the second end of the secondary winding (N2) is electrically connected to the thyristor (T N2 )’s anode connection; The thyristor (T N2 ) is connected to the connection point of the capacitor branch (40) and the capacitor charging resistor branch (50).

10. A control method for a solid-state DC circuit breaker based on a three-winding coupled inductor according to any one of claims 1 to 9, characterized in that: The following steps are involved: When the branch to be charged is fully charged through the left charging branch or the right charging branch, it is determined whether the DC system starts to start; When it is determined that the DC system starts to start, a conduction signal is generated and sent to the flow branch, and it is determined whether the current of the flow branch passes through zero during normal operation; When it is determined that the current of the through-current branch does not pass zero during normal operation, it is determined whether the through-current branch receives a current disconnection signal from the DC system; When it is determined that the current of the flow branch passes through zero during normal operation, the step of generating a conduction signal and sending it to the flow branch, and determining whether the current of the flow branch passes through zero during normal operation; When it is determined that the flow branch has not received the current disconnection signal of the DC system, the step of determining whether the current of the flow branch passes through zero during normal operation is performed; When it is determined that the through-current branch receives the current disconnection signal of the DC system, it is determined whether the current flow direction of the through-current branch flows from the left charging branch direction to the right charging branch direction; When it is determined that the current flow direction of the current-passing branch is from the left charging branch to the right charging branch, the first coupled inductor branch is turned on; When it is determined that the current flow direction of the current-passing branch is not from the left charging branch to the right charging branch, the second coupled inductor branch is turned on; Determining whether the DC system needs reclosing; When it is determined that the DC system needs to be reclosed, the process proceeds to the step of determining whether the DC system starts to start after the branch to be charged is fully charged via the left charging branch or the right charging branch; When it is determined that the DC system does not require reclosing, the process ends.

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