A bilateral self-powered bidirectional dc solid state circuit breaker

Abstract

A bidirectional DC solid-state circuit breaker with dual-sided self-powered power supply includes a bidirectional solid-state switch, a DC / DC converter, and an energy absorption circuit, the energy absorption circuit including a capacitor. C Varistors (MOVs), Diodes D 1. D 2 and grounding resistance R The source of SiC power switch J1 in the bidirectional solid-state switch is connected to the power supply side, and the source of SiC power switch J2 is connected to the line side after passing through the detection unit; capacitor C One end is connected to the drain of SiC power switching transistors J1 and J2, and the other end is pulled down to ground by a resistor. R ; Varistor MOV and capacitor C Parallel connection; diode D 1. D 2. Using a common anode configuration in anti-series connection, diodes D 1. D The cathodes of transistors 2 are connected to the sources of SiC power switches J1 and J2, respectively; the input of the DC / DC converter is connected to the capacitor. C The two ends are connected, and the DC / DC converter will connect the capacitor. C The voltage on the circuit is stepped down and isolated to power the detection unit, control unit, and drive unit; the drive unit controls the turn-off of SiC power switches J1 and J2. This invention enables flexible dual-side power supply and uninterrupted self-powering.

Description

Technical Field

[0001] This invention relates to the field of DC power distribution system protection technology, and in particular to a bidirectional DC solid-state circuit breaker with dual-sided self-powered operation. Background Technology

[0002] With the development of new energy power generation technologies such as wind power and photovoltaic power, distributed energy will be widely used in future power grids. Over the past few decades, DC power grids have received widespread attention from industry and academia due to the development of technologies such as wind power, photovoltaic power, hybrid energy storage, electric vehicles, and DC home appliances. Compared with AC power grids, DC power grids have advantages such as high efficiency, low reactive power loss, higher power quality, easier integration of DC power supplies, and no need for synchronization. However, due to the low impedance and small moment of inertia of DC power grid systems, the fault current rises rapidly and has a large amplitude during short-circuit faults. If mechanical switches are used to cut off the fault current, a high-voltage, large electric arc will be generated at the moment of cutting off, which can seriously burn out electrical equipment. Furthermore, mechanical switches have a slow segmentation speed. Fast, arc-free DC solid-state circuit breakers effectively solve these problems and have thus become a current research hotspot. However, due to the integration of various distributed generation systems, the DC system has changed from a single-ended power supply system to a dual-ended or multi-ended power supply system. The power transmission characteristics of the system have also changed, from unidirectional transmission in a single-ended system to bidirectional flow in a dual-ended or multi-ended system. However, due to the unidirectional turn-off characteristic of the power semiconductors that constitute the main power switch of the DC solid-state circuit breaker, it is impossible to achieve the function of bidirectional interruption, which has led to the demand for bidirectional solid-state circuit breakers (BSSBs).

[0003] Currently, most developed BSSCBs cannot be directly placed in power lines and require additional power supplies or auxiliary power lines. Although a small number of BSSCBs have achieved self-powering, they still have many shortcomings. Their self-powering solutions can be roughly divided into the following three types, such as... Figure 1 As shown. Figure 1 The self-powered methods shown in (a) and 1(b) simply draw power from one side of the BSSCB. However, if a short-circuit fault occurs on that side, it will severely affect the stability of the power supply, and may even lead to power supply failure. When using methods such as Figure 1(c) shows the power extraction method, where the voltage drop across the BSCB power switching device due to the excess fault current is used as the starting voltage to activate the circuit breaker's control unit and interrupt the fault current. This power extraction method is simple and easy to implement, and the auxiliary unit does not incur any losses when the BSCB is operating normally. However, this power extraction method prevents the BSCB from performing its normal interruption and real-time monitoring functions. Furthermore, its shutdown trigger condition is determined by the internal resistance of the power switching device and the startup voltage of the chip controlling the power switching device's shutdown. This results in a significant limitation as it cannot flexibly set the short-circuit threshold current according to application requirements. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a bidirectional DC solid-state circuit breaker that can achieve flexible power supply from both sides and uninterrupted self-power supply.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical method: a bidirectional DC solid-state circuit breaker with dual-sided self-powered operation, comprising a bidirectional solid-state switch, a detection unit, a control unit, and a drive unit, wherein the bidirectional solid-state switch is composed of SiC power switching transistors J1 and J2 connected in anti-series configuration with common drain; it also includes a DC / DC converter and an energy absorption circuit, wherein the energy absorption circuit includes a capacitor. C Varistors (MOVs), Diodes D 1. D 2 and grounding resistance R ;

[0006] The source of the SiC power switch J1 is connected to the power supply side, and a voltage source is connected to the power supply side. V 1. The source of the SiC power switch J2 is connected to the line side after passing through the detection unit, and a voltage source is connected to the line side. V 2; the capacitor C One end is connected to the drain of SiC power switching transistors J1 and J2, and the other end is pulled down to ground by a resistor. R The varistor MOV and capacitor C Parallel connection; the diodes D 1. D 2. Using a common anode configuration in anti-series connection, diodes D 1. D The cathodes of transistors 2 are connected to the sources of SiC power switches J1 and J2, respectively; the input terminal of the DC / DC converter is connected to the capacitor. C The two ends are connected, and the DC / DC converter will connect the capacitor. C The voltage on the device is stepped down and isolated to power the detection unit, control unit, and drive unit. The output of the detection unit is connected to the input of the control unit, the output of the control unit is connected to the input of the drive unit, and the output of the drive unit is connected to the gates of the SiC power switches J1 and J2.

[0007] Preferably, the grounding resistance R The value constraints are:

[0008] (1)

[0009] (2)

[0010] In the formula, This is the clamping voltage of the varistor MOV; This refers to the drain-source breakdown voltages of SiC power switching transistors J1 and J2. This is the maximum safe input voltage for the DC / DC converter. This refers to the power supply voltage. This is the maximum allowable difference in fault current between the two sides of a bidirectional DC solid-state circuit breaker.

[0011] Preferably, the value of the capacitor C is constrained as follows:

[0012] (3)

[0013] In the formula, Set a threshold for short-circuit current; For line inductance; This is the minimum safe input voltage for the DC / DC converter.

[0014] Furthermore, the bidirectional DC solid-state circuit breaker also includes a communication unit connected to the control unit, which is powered by a DC / DC converter.

[0015] Preferably, the SiC power switches J1 and J2 are SiC JFET type switches.

[0016] Preferably, a TVS transient voltage suppressor or a GDT ceramic gas discharge tube is used to replace the varistor MOV.

[0017] The bidirectional DC solid-state circuit breaker provided by this invention can achieve uninterrupted self-powered operation from both sides without the need for additional auxiliary power supply equipment or auxiliary power supply lines. Compared with the traditional method of self-powering a BSCB by drawing power from one side, this invention can draw power from both sides of the BSCB, avoiding the power supply failure problem that may occur when a fault occurs on the self-powered side, and improving the stable operation and reliable fault isolation capability of the BSCB. In addition, the traditional method of drawing power from the circuit breaker voltage drop means that the BSCB is in a state of no power supply after the fault is isolated or before the fault occurs, while this invention can support uninterrupted power supply to the BSCB, so that the BSCB can not only achieve fault isolation, but also have the functions of immediate disconnection, real-time monitoring and system communication. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the existing BSCCB self-powered method;

[0019] Figure 2 This is a schematic diagram of the flexible dual-sided power supply method for BSCB provided by the present invention;

[0020] Figure 3 This is a diagram of a bidirectional DC solid-state circuit breaker with dual-sided self-powered circuit breaker provided by the present invention;

[0021] Figure 4 This is a simplified model diagram of a line-side short-circuit fault in an embodiment of the present invention;

[0022] Figure 5 This is a waveform diagram of the BSSCB line-side fault response in an embodiment of the present invention;

[0023] Figure 6 This is a schematic diagram of the entire process of isolating a short-circuit fault on the line side in an embodiment of the present invention;

[0024] Figure 7 This is a simplified model diagram of a short-circuit fault on the power supply side in an embodiment of the present invention;

[0025] Figure 8 This is a waveform diagram of the BSCB power supply side fault response in an embodiment of the present invention;

[0026] Figure 9 This is a schematic diagram of the entire process of power supply side short circuit fault isolation in an embodiment of the present invention;

[0027] Figure 10 This is a topology diagram of the experimental platform in an embodiment of the present invention;

[0028] Figure 11 This is a waveform diagram of the experimental results in an embodiment of the present invention. Detailed Implementation

[0029] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments and accompanying drawings. The content mentioned in the embodiments is not intended to limit the present invention.

[0030] As described in the background section, in applications of two-terminal or multi-terminal DC systems, the method of self-powering the BSCB by drawing power from only one side of the circuit breaker or from the voltage drop of the circuit breaker has significant drawbacks and limitations. Therefore, this invention proposes a self-powered topology that can flexibly draw power from both sides of the BSCB, such as... Figure 2As shown, regardless of which side of the BSSCB the short-circuit fault occurs on, it can obtain stable power from the normally operating side and quickly respond to the fault by cutting off the fault current, thereby isolating the fault and ensuring the safe and stable operation of the system outside the fault. Simultaneously, it can overcome... Figure 1 (c) The limitation of power failure under normal conditions brought about by this self-powered scheme enables the disconnection function and online monitoring function under normal system operation, thus promoting the digitalization and informatization of the power grid.

[0031] like Figure 3 As shown, a bidirectional self-powered DC solid-state circuit breaker includes a bidirectional solid-state switch, a detection unit, a control unit, a drive unit, a communication unit, a DC / DC converter, and an energy absorption circuit. The DC / DC converter consists of a transformer with step-down isolation and a step-down isolation chip, among other components. The step-down isolation chip plays a driving and control role in the DC / DC converter, achieving a stable output voltage. The energy absorption circuit includes a capacitor. C Varistors (MOVs), Diodes D 1. D 2 and grounding resistance R As the most important energy absorption element in the energy absorption circuit, the MOV varistor can be replaced by a TVS transient voltage suppressor or a GDT ceramic gas discharge tube.

[0032] The connection relationships between the above circuit components are shown in [reference]. Figure 3 The bidirectional solid-state switch consists of two common-drain SiC power switches, J1 and J2 (both SiC JFET type switches), connected in anti-series. The source of SiC power switch J1 is connected to the power supply side, which is connected to a voltage source. V 1. The source of the SiC power switch J2 is connected to the line side after passing through the detection unit, and a voltage source is connected to the line side. V 2; Capacitor C One end is connected to the drain of SiC power switching transistors J1 and J2, and the other end is pulled down to ground by a resistor. R ; Varistor MOV and capacitor C Parallel connection; diode D 1. D 2. Using a common anode configuration in anti-series connection, diodes D 1. D The cathodes of transistors 2 are connected to the sources of SiC power switches J1 and J2, respectively; the input of the DC / DC converter is connected to the capacitor. C The two ends are connected, and the DC / DC converter will connect the capacitor. C The voltage on the capacitor is stepped down and isolated to power the detection unit, control unit, communication unit, and drive unit. CThe voltage is crucial for the BSCB to obtain stable power; the output of the detection unit is connected to the input of the control unit, the output of the control unit is connected to the input of the drive unit, and the output of the drive unit is connected to the gates of the SiC power switches J1 and J2.

[0033] The following section explains the working principle of how a BSCB, when installed in a two-terminal DC system, maintains continuous self-power supply in the face of different short-circuit faults. The power transmission cable is considered equivalent to an inductor. L Voltage source V 1. V 2 is a two-terminal DC power supply.

[0034] (1) Analysis of BSSCB response process under line-side short-circuit fault

[0035] Normally, the BSSCB is installed close to the power supply side. When a short-circuit fault occurs in the line, the line inductance varies depending on the location of the fault. L L There will be differences, such as Figure 4 The diagram shows a simplified model of a line short-circuit fault; the BSSCB response process includes 7 stages, such as... Figure 5 As shown; Figure 6 The entire process of BSSCB clearing fault current is described in detail.

[0036] Phase I (0- t 0): such as Figure 6 As shown in (a), the rated current of the DC system during normal operation is... At a preset threshold Within this range, BSCCB will not be triggered.

[0037] Phase II ( t 0- t 1): For example Figure 6 As shown in (b), when a short-circuit fault occurs in the line, the current in the line rises rapidly because of the on-state internal resistance of the SiC JFET. R ON Very small, practically negligible, power supply side current and line-side current The formula for current increase is equation (4);

[0038] (4)

[0039] In the formula, This refers to the power supply voltage. This refers to the line inductance.

[0040] Phase III t 1- t 2): For example Figure 6As shown in (b), this stage is the short-circuit fault response time, which occurs when the short-circuit current reaches the threshold. Afterwards, the current is sampled by the detection unit and reaches the control unit. After processing by the control unit, a turn-off signal is sent to the drive unit, and finally the SiC JFET turns off. The current rise formula in this stage is Equation (5);

[0041] (5)

[0042] Phase IV t 2- t 3): For example Figure 6 As shown in (c), after the BSSCB performs the turn-off action, the power switch J2 blocks the fault current, and the line inductance... The fault current passes through the self-powered capacitor. C Absorption and grounding resistance R Freewheeling, current and capacitance in the system C Voltage at both ends The changes are as shown in equation (6);

[0043] (6)

[0044] In the formula, This refers to the short-circuit fault current in the line.

[0045] Stage V ( t 3- t 4): For example Figure 6 As shown in (d), when the capacitor C The clamping voltage of the varistor MOV absorbs fault current. Subsequently, the fault current is transferred to the varistor MOV branch for absorption, affecting the current and capacitance in the system. C Voltage at both ends The changes are shown in equation (7);

[0046] (7)

[0047] Stage VI ( t 4- t 5): For example Figure 6 (e) shows that at this stage, the current in the line inductance is almost gone, and only the grounding resistor needs to be connected. R Freewheeling occurs; simultaneously, power switch J1 blocks the capacitor. C to voltage source V 1. The current drawn in, and the voltage across the power switch J1 are: .

[0048] Phase VII ( t 5- t 6): For example Figure 6As shown in (f), the detection unit, control unit, and drive unit all use self-powered capacitors. C To provide power, the capacitor C The absorbed fault current energy is absorbed and reused, ultimately benefiting the capacitor. C The voltage returns to V DC .

[0049] (2) Analysis of BSCCB response process under power supply side short circuit fault

[0050] When a short-circuit fault occurs on the power supply side, its simplified short-circuit fault model is as follows: Figure 7 As shown. The BSSCB response process includes 7 stages, as follows: Figure 8 As shown; Figure 9 The entire process of BSSCB clearing fault current is described in detail.

[0051] Phase I (0- t 0): such as Figure 9 As shown in (a), when the DC system is operating normally, the circuit in the line changes according to the power flow. If the threshold is within the safe range, the BSSCB will not be triggered.

[0052] Phase II ( t 0- t 1): For example Figure 9 As shown in (b), when a short-circuit fault occurs on the busbar, the short-circuit current is generated by the voltage source. V 2. Through line inductance and capacitor C The line-side current discharges to the short-circuit fault through the RC circuit. Busbar side current and capacitor C Voltage at both ends For example, equation (8);

[0053] (8)

[0054] Phase III t 1- t 2): Similar to line-side faults, this stage is the time for the BSSCB to respond to the threshold current, and it is a continuation of the previous stage.

[0055] Phase IV t 2- t 3): For example Figure 9 As shown in (c), this stage is similar to a line fault, but with different grounding resistance. R The capacitor does not participate in this process. C Absorbing fault current, current changes in the system and The changes are as shown in equation (9);

[0056] (9)

[0057] Stage V ( t 3- t 4): For example Figure 9 As shown in (d), this stage is similar to a line fault, but the resistance... R Not participating in this process, the fault current is transferred to the varistor MOV branch, and the current change in the system and The changes are as shown in equation (10);

[0058] (10)

[0059] Stage VI ( t 4- t 5): For example Figure 9 As shown in (e), similar to a line fault, power switch J2 blocked the capacitor. C to voltage source V 2. The current drawn in, and the voltage across the power switch J1 are: However, due to the line inductance There is no current flowing through it, so no resistor is needed. R Continuous streaming.

[0060] Phase VII ( t 5- t 6): For example Figure 9 As shown in (e), the detection unit, control unit, and drive unit all use self-powered capacitors. C To provide power, the capacitor C The absorbed fault current energy is absorbed and reused, ultimately benefiting the capacitor. C Voltage return to .

[0061] Based on the aforementioned short-circuit fault analysis, the design of some important circuit parameters in this invention is as follows.

[0062] 1) Grounding resistance R

[0063] Based on the above analysis of the line fault process, it can be seen that the grounding resistance... R This will affect the fault current clearing speed on both the bus and line sides. If the grounding resistance... R If the grounding resistance is relatively small, the fault current clearing speed on the bus side will be extremely fast, while the fault current clearing speed on the line side will be slow, seriously affecting the safety of the line-side equipment. Therefore, it can be concluded that the grounding resistance... R The value of should be chosen to ensure that the fault currents on both sides are disconnected synchronously as much as possible. Therefore, the maximum allowable difference between the fault currents on both sides of the bidirectional DC solid-state circuit breaker is first set to . Analysis of the line fault clearing process shows that the maximum difference in fault current between the two sides occurs at... t 4 moments, that is ,like Figure 5 As shown; therefore, combining equation (7), it can be seen that the resistance R The value of should satisfy the following equation (1);

[0064] (1)

[0065] 2) Varistor MOV

[0066] Clamping voltage of varistor MOV This directly relates to the fault current clearing speed. From equations (7) and (10), it can be seen that when the varistor MOV is equivalent to a constant voltage source model, the rate of decrease of the fault current on the line inductance is related to the clamping voltage. Voltage source The difference is proportional to the clamping voltage. Higher voltage ratings result in faster fault clearing speeds, but also higher drain-source voltages that the SiC JFET switching device must withstand. When this voltage exceeds the drain-source breakdown voltage... It can even break down SiCJFETs, so the clamping voltage needs to be controlled. Limit it; same capacitor C Voltage range ( , These represent the maximum and minimum safe input voltages of the DC / DC converter, respectively, and the clamping voltage. There are also limitations. Therefore, the clamping voltage of the varistor MOV... It should satisfy the following equation (2);

[0067] (2)

[0068] 3) Self-powered capacitors C

[0069] First, based on the above analysis of the busbar fault process, it can be seen that when a short-circuit fault occurs on the busbar, not only will the line side release short-circuit current to the fault point, but the grounding resistance in the BSSCB will also be affected. R and self-generated capacitors C The formation of an RC circuit will also release short-circuit current to the fault point, which will cause the capacitor to... C The voltage will drop exponentially, and the power supply for both the BSSCB detection unit and the control unit is drawn from the capacitor. C Therefore, capacitor C The value should be chosen to ensure that the fault current reaches Maintain at minimum input voltage Above, that is Combining equation (8), it can be seen that the capacitance C The value of should satisfy the following equation (3);

[0070] (3)

[0071] Secondly, capacitors C The value of is related to the speed at which the BSCB clears short-circuit faults, especially when a line fault occurs and the fault point is close to the BSCB, and the line inductance L L The value is essentially zero if the capacitance is low. C If the capacitor is too large, it will affect the turn-off speed of the BSSCB, so the capacitor... C The value of is as small as possible while satisfying equation (3).

[0072] This invention ensures a continuous and stable power supply to all units within the BSCB when responding to short-circuit faults occurring on either side of it, thus providing support for the BSCB to clear the short-circuit fault and ensure the safe and stable operation of the system. Furthermore, after isolating the fault area, the BSCB can still stably self-power itself to ensure its normal operation, providing a basis for subsequent system communication and guiding the BSCB to reclose and restore normal system power supply.

[0073] To verify the effectiveness of the BSSCB self-powered scheme proposed in this invention, this embodiment establishes the following... Figure 10 The experimental platform shown includes a voltage source. V 1. V 2 is a 400V DC power supply, capacitor C DC It is a 3.3mF large capacitor formed by cascading capacitors; switch K Switching 1 enables the DC source to charge and discharge the large capacitor, while the switch... K The closing of 2 simulates a short-circuit fault. Figure 10 (a) Simulating a line-side short-circuit fault, the line inductance L L The value (0~5mH) will vary depending on the location of the fault. Figure 10 (b) Simulating a short-circuit fault on the power supply side, the line inductance L L The maximum value (5mH); the parameters of each device used in the BSCB, the DC / DC converter parameters, and the fault current setting threshold. I th As shown in Table 1 below:

[0074] ;

[0075] This implementation method uses a 400V / 20A BSCB prototype for short-circuit fault testing, and the experimental waveform is as follows. Figure 11 As shown, This refers to the short-circuit fault current in the line. This is the gate drive voltage of the SiC JFET. For capacitor C Voltage at both ends, This refers to the output voltage of the DC / DC converter.

[0076] Depend on Figure 11 (a) It can be seen that when simulating a short-circuit fault on the line side, the line inductance is taken. L L When the threshold current is 0, the fault current rises linearly. After reaching the threshold current of 40A, the BSSCB, after a 500ns response time, interrupts the fault current when it reaches 68A, and cuts off the fault current within 2µs. The capacitor... C The voltage is stable within the normal supply voltage range; by Figure 11 (b) It can be seen that when simulating a short-circuit fault on the line side, the line inductance is taken. L L When the capacitance is 5mH, the BSSCB can quickly cut off the fault current when the fault current reaches the threshold current of 40A, and the capacitor... C The voltage is stable within the normal supply voltage range; by Figure 11 (c) It can be seen that during a simulated short-circuit fault on the power supply side, the fault current rises rapidly while the capacitor... C The voltage decreases due to the discharge of the RC circuit, but it still maintains 330V when the BSCB cuts off the fault current, which is higher than the minimum safe supply voltage of 210V. Therefore, this experiment effectively demonstrates that the BSCB provided by this invention can stably self-power under various fault conditions, ensuring rapid fault clearance and safe and stable system operation.

[0077] The above embodiments are preferred implementations of the present invention. In addition, the present invention can be implemented in other ways. Any obvious substitutions without departing from the concept of the present technical solution are within the protection scope of the present invention.

[0078] To facilitate understanding by those skilled in the art of the improvements of this invention over the prior art, some of the accompanying drawings and descriptions have been simplified, and for clarity, some other elements have been omitted from this application. Those skilled in the art should realize that these omitted elements may also constitute the content of this invention.

Claims

1. A bidirectional DC solid-state circuit breaker with dual-sided self-powered operation, comprising a bidirectional solid-state switch, a detection unit, a control unit, and a drive unit, wherein the bidirectional solid-state switch is composed of SiC power switching transistors J1 and J2 connected in reverse series with a common drain, characterized in that: Also included are a DC / DC converter and an energy absorption circuit, the energy absorption circuit including a capacitor C , a varistor MOV, a diode D 1, D 2 and a ground resistor R ; The source of the SiC power switch J1 is connected to the power supply side, and a voltage source is connected to the power supply side. V 1. The source of the SiC power switch J2 is connected to the line side after passing through the detection unit, and a voltage source is connected to the line side. V 2; the capacitor C One end is connected to the drain of SiC power switching transistors J1 and J2, and the other end is pulled down to ground by a resistor. R The varistor MOV and capacitor C Parallel connection; the diodes D 1. D 2. Using a common anode configuration in anti-series connection, diodes D 1. D The cathodes of transistors 2 are connected to the sources of SiC power switches J1 and J2, respectively; the input terminal of the DC / DC converter is connected to the capacitor. C The two ends are connected, and the DC / DC converter will connect the capacitor. C The voltage on the device is stepped down and isolated to power the detection unit, control unit, and drive unit. The output of the detection unit is connected to the input of the control unit, the output of the control unit is connected to the input of the drive unit, and the output of the drive unit is connected to the gates of the SiC power switches J1 and J2.

2. The bidirectional DC solid-state circuit breaker with dual-sided self-powered operation according to claim 1, characterized in that: The grounding resistance R The value constraints are: (1) (2) In the formula, This is the clamping voltage of the varistor MOV; This refers to the drain-source breakdown voltages of SiC power switching transistors J1 and J2. This is the maximum safe input voltage for the DC / DC converter. This refers to the power supply voltage. This is the maximum allowable difference in fault current between the two sides of a bidirectional DC solid-state circuit breaker.

3. The bidirectional DC solid-state circuit breaker with dual-sided self-powered operation according to claim 2, characterized in that: The value of the capacitor C is subject to the following constraints: (3) In the formula, Set a threshold for short-circuit current; For line inductance; This is the minimum safe input voltage for the DC / DC converter.

4. The bidirectional DC solid-state circuit breaker with dual-sided self-powered operation according to claim 3, characterized in that: The bidirectional DC solid-state circuit breaker also includes a communication unit connected to the control unit, which is powered by a DC / DC converter.

5. The bidirectional DC solid-state circuit breaker with dual-sided self-powered operation according to claim 4, characterized in that: The SiC power switches J1 and J2 are SiC JFET type switches.

6. The bidirectional DC solid-state circuit breaker with dual-sided self-powered operation according to claim 1, characterized in that: The varistor MOV can be replaced with a TVS transient voltage suppressor or a GDT ceramic gas discharge tube.

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