# Modular Clamping Circuit for High Speed Solid State Circuit Breakers

Florian Kapaun, Christopher Dahmen, Gerhard Steiner, Michael Witti

► To cite this version:

Florian Kapaun, Christopher Dahmen, Gerhard Steiner, Michael Witti. Modular Clamping Circuit for High Speed Solid State Circuit Breakers. The 26th European Conference on Power Electronics and Applications, GDR SEEDS France & EPE Association, Mar 2025, Paris, France. 10.34746/epe2025-0240. hal-05088466

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Submitted on 28 May 2025

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# Modular Clamping Circuit for High Speed Solid State Circuit Breakers

Florian Kapaun

Central Research & Technology
Airbus

Taufkirchen, Germany
florian.kapaun@airbus.com

Christopher Dahmen

Central Research & Technology
Airbus

Taufkirchen, Germany
christopher.dahmen@airbus.com

Gerhard Steiner

Central Research & Technology
Airbus

Taufkirchen, Germany
gerhard.steiner@airbus.com

Michael Witti

Central Research & Technology
Airbus

Taufkirchen, Germany
michael.witti@airbus.com

**Abstract**—The aviation industry is on the cusp of a revolutionary transformation with the advent of zero-emission aircraft. These innovative aircraft, powered by cutting-edge technologies such as electric propulsion and hydrogen fuel cells, promise to significantly reduce the environmental impact of air travel. As global awareness of climate change and sustainability grows, the development and adoption of zero-emission aircraft are becoming increasingly vital.

However, the integration of these advanced technologies necessitates robust electrical network protection to ensure safety and reliability. This leads to the need for advanced protection circuits, such as Solid-State Circuit Breakers (SSCBs) and clamping circuits, which are essential for managing the complexities of modern electrical systems.

This paper focuses on an advanced clamping circuit that enables efficient voltage clamping for high-speed SSCBs. The method effectively clamps overvoltage in failure cases, realizing almost no voltage overshoot and a minimum time to clear the fault current. Due to its complete analog nature it is very suitable for safety critical applications where active digital control circuits have to be avoided. The proposed method is very efficient, ensuring the stability and safety of electrical networks in zero-emission aircraft.

**Index Terms**—SSCB, voltage clamping, dc-network, electric propulsion

## I. INTRODUCTION

The implementation of DC microgrids is poised to become a cornerstone of future electric aircraft systems (EAS). A critical function within DC microgrids is the ability to disconnect grid nodes that connect sub-grids, power sources, or potential sinks, either due to component failures (such as short circuits) or to facilitate the intentional shutdown of part of the system [1]. Due to the inherently low-impedance structure of DC microgrids, faults can result in extremely steep current slopes resulting in high short circuit currents. In the context of EAS, where weight is a paramount consideration, oversizing components is not a feasible solution. Furthermore, current values exceeding the nominal range by more than a factor of four are intolerable. This necessitates the ability to interrupt fault

currents within an exceptionally short timeframe, typically below 10 microseconds [2].

Given these stringent requirements, mechanical switchgear or conventional hybrid topologies are insufficient as they cannot interrupt fault loops quickly enough to prevent damage to other components in the microgrid [3]. This limitation has brought solid-state circuit breakers (SSCBs) into focus as a viable solution [4].

SSCBs are advanced protective devices designed to interrupt current flow rapidly in the event of a fault [5]. Unlike traditional mechanical circuit breakers, SSCBs utilize power semiconductor devices - such as silicon carbide (SiC) MOS-FETs - that enable ultra-fast fault isolation without producing arcing. This characteristic makes SSCBs highly efficient and reliable, particularly for modern electrical systems such as DC microgrids, electric vehicles, and renewable energy applications.

A significant challenge in deploying SSCBs is mitigating the overvoltage transients that occur during rapid current interruption [6]. When fault currents are interrupted, the energy stored in the inductive components of the system induces high voltage spikes across the semiconductor switch. To safeguard both the SSCB and other components in the network from over-voltage damage, specialized voltage-clamping circuits must be employed [7], [8].

## II. SOLID-STATE CIRCUIT BREAKERS AND CLAMPING CIRCUITS

### A. General structure of Solid-state circuit breakers

A solid-state circuit breaker (see Fig. 1) is composed of several fundamental functional blocks, each playing a critical role in providing fast and reliable protection in electrical systems. These blocks work together to ensure the system's safety and efficiency. The central element of the SSCB is the power semiconductor, such as a MOSFET, IGBT, or wide-bandgap devices like SiC or GaN. This component manages
<figure><img src="image_2.png" /><figcaption>Fig. 1. Function blocks of a common solid-state circuit breaker</figcaption></figure>

the switching and current interruption, allowing for precise control during fault events.

The **gate drive unit** is responsible for controlling the power semiconductor. It converts control signals into the appropriate gate commands, enabling the semiconductor to switch rapidly between states, ensuring quick fault response.

To protect the system from potential overvoltage during faults, a **voltage clamping circuit** has to be implemented. This block safeguards the power semiconductor and other key components from damage caused by voltage spikes.

The **sense and trip electronics** continuously monitors the system for irregularities, such as overcurrent or short circuits. Once a fault is detected, it signals the gate drive unit to open the breaker, quickly isolating the fault to prevent further damage.

Finally, the **auxiliary power** ensures that the gate driver, sensing circuits, and control electronics have a stable low-voltage power supply. This guarantees that the SSCB remains operational and responsive under various operating conditions.

## B. State of the art for clamping circuits

Power electronics clamping circuits play a crucial role in protecting electronic devices from voltage spikes and transients [9]. These circuits are designed to limit or “clamp” the voltage to a safe level, preventing damage to sensitive components. Clamping circuits are commonly used in various applications, including power supplies, motor drives, and communication systems.

The primary function of a clamping circuit is to keep away excess voltage from the all electronic circuit components, ensuring that the voltage remains within a specified range. This is achieved using components and technologies such as:

* **Metal Oxide Varistors (MOVs)**: MOVs are widely used for their ability to handle high energy transients [10]. They exhibit high impedance at low voltages and rapidly decrease in impedance when the voltage exceeds a certain threshold, allowing them to absorb and dissipate the excess energy.

* **Transient Voltage Suppressor (TVS) Diodes**: TVS diodes provide precise clamping voltage and fast response time, making them suitable for protecting sensitive electronic components from transient voltage spikes.

* **Snubber Circuits**: Snubber circuits, such as resistor-capacitor (RC) and resistor-capacitor-diode (RCD) snubbers, are used to control the rate of voltage rise and limit the peak voltage across the semiconductor switch. These circuits help dissipate the energy stored in the inductive elements and reduce the stress on the SSCB [11].

* **Gas Discharge Tubes (GDT)**: These are used in high-energy applications to protect against surges and lightning e.g. in avionics [12] by diverting the excess energy away from the protected circuit.

* **Active voltage clamping (AVC)**: In comparison to the above mentioned types of clamping, active voltage clamping is a technique where the clamping is actively controlled e.g. via a clamping element in combination with a semiconductor switch [13].

All the mentioned clamping components and technologies show different properties and capabilities. Not just the single component itself but also a combination of multiple components or combination of different technologies can be used to achieve the desired clamping performance for a specific application.

## C. Choice of the most promising technology

To gain a better understanding of the most promising components and technologies, a literature review was conducted and verified through simulations. Given that GDTs do not offer high energy capability and introduce a very low ohmic path [14], they are not considered in this paper. The remaining components have been compared based on their pros and cons. A brief classification and assessment are shown in Table I, with evaluations ranging from “++” for very high to “- -” for very low. The color code indicates advantageous (green) or disadvantageous (red) behavior.

<table><caption>TABLE I
COMPARISON OF MOST PROMISING CLAMPING TECHNOLOGIES</caption><thead><tr><th>Property</th><th>MOV</th><th>TVS</th><th>AVC</th><th>Snubber</th></tr></thead><tbody><tr><td>Complexity</td><td>■</td><td>■</td><td>■</td><td>0</td></tr><tr><td>Clamping factor</td><td>0</td><td>+</td><td>+</td><td>■</td></tr><tr><td>Energy capability</td><td>■</td><td>■</td><td>0</td><td>■</td></tr><tr><td>Weight</td><td>■</td><td>■</td><td>0</td><td>0</td></tr></tbody></table>

For aircraft applications, safety is paramount [15], therefore active solutions should be avoided whenever possible. Due to its low energy capability, classical snubber circuits are not further considered. As shown in Table I, none of the mentioned options provide a perfect solution in all aspects. Therefore, further research is needed to optimize the clamping performance with the help of additional circuits. Considering degradation, simplicity, adaptability, and maximum energy consumption, the TVS diode offers a solid foundation. Thus, this technology was selected for further investigation in this paper.
### III. VOLTAGE CLAMPING CIRCUIT

#### A. Energetic considerations

The targeted system to demonstrate the use of SSCB and clamping circuit is modeled according to a typical aircraft scenario. The operating voltage is specified as $V_{DC} = 800$ V DC, and the nominal operating current is defined as $I_{nom} = 400$ A. Due to the network expansion ($\approx 75$m), the maximum line inductance is roughly $150 \mu H$. During turn-on and reconfiguration, higher current values are typically required, allowing an increased current of up to $I_{inrush} = 2 \cdot I_{nom} = 800$ A for a specific period of up to half a second. A current value above $I_{SC} = 1$ kA is desired as the short circuit current, which directly triggers the turn-off of the SSCB. Therefore, 1 kA is used for the energy calculation that must be dissipated in the event of a failure.

The energy stored in the network is primarily due to the line inductance and can be calculated using the following equation:

$$E_L = \frac{1}{2} \cdot L \cdot I_{SC}^2 \quad (1)$$

In the event of a failure, the source continues to feed power into the circuit. This additional power contributes significantly to the overall energy that must be dissipated by the clamping circuit. The energy delivered by the source can be calculated using the following equation:

$$E_S = V_{DC} \cdot \int_{0}^{t_{clamp}} i_{SC}(t) dt \quad (2)$$

During the timespan of $t_{clamp}$, the SSCB is turned off, and the current is completely taken by the clamping circuit. The current decreases linearly until it reaches 0 A. $V_{DC}$ is considered constant during this period. The integral can be calculated as follows:

$$E_S = \frac{1}{2} \cdot V_{DC} \cdot I_{SC} \cdot t_{clamp} \quad (3)$$

Combining the energies, results in:

$$E = E_L + E_S = \frac{1}{2} \cdot I_{SC} \cdot (L \cdot I_{SC} + V_{DC} \cdot t_{clamp}) \quad (4)$$

Assuming the values given above, and an experimental determined value $t_{clamp} = 312 \mu s$, the energy dissipation in case of failure is:

$$E = E_L + E_S = 75 J + 125 J = 200 J \quad (5)$$

This means that only 20% of the total energy is stored in the line inductance, which can only be reduced by lowering the cut-off current or reducing parasitic network effects. However, 80% of the energy comes from the source. This value can be significantly reduced by increasing the clamping voltage and therefore the clamping factor. This measure decreases the total time $t_{clamp}$ during which the transient event occurs, thereby reducing the drawn energy.

#### B. TVS-Diodes

When designing a clamping circuit with TVS diodes, several key parameters must be considered. The most important ones are listed below:

* **Standoff Voltage ($V_{standoff}$):** The voltage at which the TVS diode begins to conduct ($\approx 10 \mu A$)

* **Transition Voltage ($V_t$):** The maximum voltage reached by the TVS during the initial clamping before it decreases to $V_{clamp}$

* **Clamping Voltage ($V_{clamp}$):** The voltage level at which the TVS diode clamps the transient voltage to a safe level

* **Peak Pulse Power ($P_{PP}$):** The maximum power the TVS diode can dissipate during a transient event without being damaged

* **Max. Energy Dissipation ($E_{TVS}$):** The maximum energy dissipation of the TVS diode

* **Foldback characteristic (see Fig 2):** A feature of some TVS diodes, particularly high-power ones, where after an initial peak $V_t$, the clamping voltage $V_{clamp}$ decreases to a lower level and remains relatively constant as the current through the device increases. This behavior provides more stable and effective protection against voltage transients by ensuring the voltage does not rise excessively even at high currents. This characteristic allows the TVS diode to handle higher surge currents without significantly increasing the clamping voltage, thereby offering better protection for sensitive electronic components.

* **Clamping Factor (CF):**

$$CF = \frac{V_{clamp}}{V_{standoff}}$$

<figure><img src="image_3.png" /><figcaption>Fig. 2. VI-characteristic of standard TVS diode and version with foldback behavior</figcaption></figure>

An essential point for dimensioning the clamping circuit is the maximum energy $E_{TVS}$ that can be dissipated by one single TVS diode. This value is not directly provided in the datasheet but can be estimated from the pulse waveform specification shown in Fig. 3. In a first-order approximation, the waveform can be represented by the triangular function, shown in pink. The enclosed area represents the total charge flowing through the diode. For the chosen AK10 diode $I_{pp}$ is given with 10 kA.
<figure><img src="image_4.png" /><figcaption>Fig. 3. Standardized 8/20µs pulse waveform</figcaption></figure>

Applying the standardized ($\frac{t_r}{t_d} = \frac{8 \mu s}{20 \mu s}$) pulse $Q_{TVS}$ can be estimated:

$$ 
\begin{aligned}
Q_{TVS} &= \int_{0}^{t_{clamp}} i_{TVS}(t)dt \\
&\approx \frac{1}{2} \cdot I_{PP} \cdot (t_r + 2 \cdot (t_d - t_r)) \\
&= \frac{1}{2} \cdot 10 \, \mu\text{A} \cdot (8 \, \mu\text{s} + 2 \cdot (20 \, \mu\text{s} - 8 \, \mu\text{s})) = 160 \, \text{mC}
\end{aligned}
\quad (6) $$

This means that at an average clamping voltage of $V_{clamp} \approx 500 \text{ V}$, the maximum energy dissipation for an AK10-430 is:

$$ E_{TVS} = V_{clamp} \cdot Q_{TVS} \approx 500 \text{ V} \cdot 160 \, \text{mC} = 80 \text{ J} \quad (7) $$

To achieve the desired energy dissipation of 200 J, a combination of multiple TVS diodes is required.

### C. Series and parallel connection of TVS diodes

Typical TVS diodes are limited to voltages up to 500 V. Standard applications, especially when realized with 2 level inverters equipped with SiC semiconductors, are operating in the voltage range of $V_{DC} \approx 800 \text{ V}$. To avoid interaction between the inverter and the clamping circuit during normal operation, the following condition has to be fulfilled:

$$ \sum V_{standoff} > V_{DC} \quad (8) $$

If the SSCB and therefore also the clamping circuit becomes active it must be granted that

$$ \sum V_t \le V_{DS} \quad (9) $$

to avoid a destructive overvoltage of the SSCB. Designing and selecting optimal TVS diodes involves balancing the risk of exceeding $V_{DC}$, staying within the maximum permissible $V_{DS}$, and minimizing the clamping voltage to approach $V_{DS}$ as closely as possible. Additionally to the voltage requirements, also the maximum energy that has to be dissipated must be considered. In many applications the arising energy is exceeding values that can be handled by single TVS diodes. Therefore it becomes necessary to connect multiple TVS diodes in

parallel. In these cases, a symmetric current distribution is essential to achieve the desired clamping performance with a minimum amount of components. Practical measurements performed at a short current of $I_{SC} = 1 \text{ kA}$ have shown that a direct parallelization of TVS diodes can lead to unequal current and therefore energy distribution (see Fig. 4). A simple

<figure><img src="image_5.png" /><figcaption>Fig. 4. Parallelization of 2 TVS diodes without balancing resistors (● = $i_{total}$, ● = $i_{D1}$, ● = $i_{D2}$)</figcaption></figure>

and effective improvement can be achieved by adding a small balancing resistor, $R_b = 20 \text{ m}\Omega$, in series with each TVS diode or each branch when multiple TVS diodes are connected in series and/or parallel. This leads to the behavior shown in Fig. 5, where the current distribution becomes significantly more balanced, and energy dissipation is evenly shared among the TVS diodes. This symmetry is crucial for optimal utilization of the paralleled TVS diodes.

<figure><img src="image_6.png" /><figcaption>Fig. 5. Parallelization of 2 TVS diodes with series balancing resistances $R_b = 20 \text{ m}\Omega$ (● = $i_{total}$, ● = $i_{D1}$, ● = $i_{D2}$)</figcaption></figure>

### D. TVS diode shift circuit

When multiple TVS diodes are connected in series to achieve higher blocking voltages, it is essential that conditions according to equations (8) and (9) are satisfied. Additionally, $V_{clamp}$ should be as close as possible to $V_{DS}$, as this directly impacts the amount of energy drawn from the DC-grid. Therefore,

$$ \sum (V_t - V_{standoff}) \quad (10) $$

must be minimized. Since TVS diode parameters are fixed during manufacturing, the only way to optimize performance is to prevent all diodes from conducting simultaneously at startup. Figure 6 illustrates a simplified simulation of three TVS diodes in series, where each diode begins conducting at a different time. This results in an overall voltage, $V_{TVS1+2+3}$, showing significantly reduced overvoltage during the transition phase. Due to the time shift of the individual $V_t$, the circuit's absolute voltage can be limited to approximately 700 V, compared to 900 V when all three diodes start to conduct simultaneously. This behavior can be achieved by placing capacitors in parallel to at least $n-1$ TVS diodes ($n$ being the number of TVS
<figure><img src="image_7.png" /><figcaption>Fig. 6. Simulation of diode shift circuit with 3 TVS diodes in series</figcaption></figure>

diodes in series). By selecting appropriate capacitance values, the activation time of each TVS diode can be adjusted. Further improvement can be achieved by using different TVS diode types (e.g. different blockings voltages) in series to optimally adapt $V_t$ and $V_{clamp}$.

An essential safety requirement for optimal circuit behavior is ensuring that the capacitors are fully discharged when the SSCB turns off. This is critical in applications such as aircraft, where the SSCB may need to be triggered multiple times in quick succession. Therefore, it is vital to rapidly discharge the capacitors after clearing the fault current. To address this, a passive discharge circuit was designed, significantly reducing discharge time and ensuring safe operation.

### E. TVS diode discharge circuit

To overcome a very slow discharge behavior and therefore a long time span in which the SSCB is not able to absorb the maximum amount of energy, a method was developed that allows rapid discharging of the diode shift capacitors.

The complete clamping circuit containing clamping elements (TVS diodes) diode shift circuit and discharge circuit is shown in Fig. 7.

## IV. TEST-SETUP AND MEASUREMENT RESULTS

### A. Component dimensioning

To achieve the desired clamping behavior with minimal overshoot, a clamping voltage close to the operating voltage, a fast recovery time after a fault and careful design of each component is essential. The clamping circuit is divided into three functional parts:

* **TVS Diode Circuit:** Responsible for voltage clamping and power dissipation.

* **Diode Shift Circuit:** Time-shifts the voltage across the diodes during fault conditions to minimize overshoot.

* **Discharge Circuit:** Enables rapid discharge of the diode shift circuit, ensuring quick recovery.

The TVS diodes are selected based on their energy ratings and VI characteristics (see section III). Once the appropriate TVS diodes are chosen, the remaining components can be dimensioned. The capacitors $C_1$ and $C_2$ determine the diode shift characteristics. Larger values of these capacitors increase

<figure><img src="image_8.png" /><figcaption>Fig. 7. Clamping circuit composed of TVS diodes, diode shift circuit and discharge circuit</figcaption></figure>

the charging time, thereby delaying the transition to the clamping state. The transition time per stage can be approximated as:

$$t_{1,2} = \frac{C_{1,2} \cdot V_{standoff}}{I_{SC}} \quad (11)$$

where $I_{SC}$ is the fault current charging the capacitor. Next, the balancing resistors $R_6$ to $R_9$ are calculated. Their values should be proportional to the standoff voltages of the parallel-connected TVS diodes, ensuring proper voltage balancing across the capacitors. Typically, these resistors have high resistance values, often in the single-digit megaohm range, for an 800 V bus system. Higher resistances reduce leakage current but increase balancing time.

The resistors $R_1$ to $R_5$ are decoupling resistors that isolate the main capacitors from the discharge capacitors during clamping. Typical values are in the range of 10 Ω. A balance must be struck between clamping quality and discharging speed, as higher resistance slows down discharging, while lower resistance allows the discharge capacitors to influence the diode shift process.

Finally, the values of the remaining capacitors ($C_3$ to $C_6$) are chosen to ensure an equal charge distribution among
the diode segments. All series-connected capacitors must be dimensioned to maintain charge balance:

$$C_3 = C_1 + C_4 = C_2 + C_5 = C_6 \quad (12)$$

## B. Clamping PCB

To verify the theoretical considerations and simulation results, a test setup was built. The clamping circuit was realized on a PCB, which is shown in Fig. 8. The TVS diodes are

<figure><img src="image_9.png" /><figcaption>Fig. 8. Clamping PCB board</figcaption></figure>

mounted on the top layer, while the capacitors, the balancing resistors, and the discharge circuit are placed on the bottom layer. The board is designed to be compact and easy to handle for testing purposes, with a direct connection to the SSCB terminals to minimize additional loop inductance.

During a clamping event, the fault current mainly flows through the TVS diodes rather than the PCB. Therefore, additional PCB layers to reduce inductance were deemed unnecessary. A copper thickness of 70 µm is sufficient to accommodate the expected clamping currents.

For the PCB, the following component values were chosen and tested (see table II). To achieve improved performance,

<table><caption>TABLE II
COMPONENTS OF THE VOLTAGE CLAMPING CIRCUIT</caption><thead><tr><th>Diode</th><th>Type</th><th>Capacitor</th><th>[µF]</th><th>Resistor</th><th>[Ω]</th></tr></thead><tbody><tr><td>D<sub>1</sub></td><td>AK10-076C</td><td>C<sub>1</sub></td><td>6</td><td>R<sub>1</sub></td><td>4,7</td></tr><tr><td>D<sub>2</sub></td><td>AK10-240C</td><td>C<sub>2</sub></td><td>2</td><td>R<sub>2</sub></td><td>10</td></tr><tr><td>D<sub>3</sub></td><td>AK10-076C</td><td>C<sub>3</sub></td><td>17</td><td>R<sub>3</sub></td><td>10</td></tr><tr><td>D<sub>4</sub></td><td>AK10-240C</td><td>C<sub>4</sub></td><td>2</td><td>R<sub>4</sub></td><td>10</td></tr><tr><td>D<sub>5</sub></td><td>AK10-430C</td><td>C<sub>5</sub></td><td>6</td><td>R<sub>5</sub></td><td>4,7</td></tr><tr><td></td><td></td><td>C<sub>6</sub></td><td>10</td><td>R<sub>6</sub></td><td>390k</td></tr><tr><td></td><td></td><td></td><td></td><td>R<sub>7</sub></td><td>1,2M</td></tr><tr><td></td><td></td><td></td><td></td><td>R<sub>8</sub></td><td>1,2M</td></tr><tr><td></td><td></td><td></td><td></td><td>R<sub>9</sub></td><td>2,2M</td></tr><tr><td></td><td></td><td></td><td></td><td>R<sub>10</sub></td><td>100m</td></tr></tbody></table>

the values for $C_3$ and $C_3$ were slightly adjusted compared to equation (12).

## C. Measurement results

To validate the theoretical calculations, the aforementioned PCB was tested under realistic conditions. The test setup

consisted of an SSCB with a 1 kA current rating and a 150 µH inductive load to simulate the network. This configuration results in a clamping energy calculated according to equation (1):

$$E_L = 75 \text{ J} \quad (13)$$

To dissipate this energy and the additional energy supplied by the source, two of the described PCB boards were connected in parallel.

Figure 9 shows the measurement results of the clamping tests ($V_{DC}$ = 800 V, $L$ = 150 µH, $I$ = 1 kA). The results indicate that the overall clamping voltage ($V_{clamp}$ = 1157 V) is only slightly higher than the summed standoff voltage of the individual TVS diodes ($V_{standoff}$ = 1062 V), resulting in a ratio of only 1.09.

Furthermore, it can be observed that the current, and consequently the energy distribution, across the two PCBs is nearly equal. This balance is achieved by placing a resistor ($R_{10}$ = 100 mΩ). On the PCB, this is realized by using a short resistance wire.

In this test, a total energy of $E$ = 197 J was dissipated by the two PCBs, of which approximately 37% originated from the energy stored in the lines. The remaining energy was supplied by the source, highlighting the critical importance of achieving the fastest possible clamping response.

## V. CONCLUSION

The presented paper introduces a novel clamping circuit for SSCBs that offers exceptional performance without the need for control or supply, using only a minimal number of non-degrading components. The circuit is composed of TVS diodes, a diode shift circuit, and a discharge circuit. The diode shift circuit allows for precise timing when triggering each TVS diode, effectively preventing the initial overshoot from accumulating across all series-connected TVS diodes. This ensures a nearly constant voltage throughout the clamping process, eliminating the need for overdimensioned components and achieving optimal clamping performance.

The circuit's precise voltage adjustability (when multiple diodes are connected) makes it highly flexible and adaptable to a wide range of applications. Furthermore, the rapid and fully passive discharging circuit guarantees minimal downtime and consistently high performance, making it particularly well-suited for safety-critical scenarios, such as in aviation.
<figure><img src="image_10.png" /><figcaption>Fig. 9. Clamping circuit performance ($V_{DC}$ = 800 V, L = 150 μH, $I_{SC}$ = 1 kA)</figcaption></figure>

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