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It is necessary to elucidate the mechanism of atmospheric arc plasma movement and the variation in its physical properties for constructing an accurate virtual model while using digital twin technology to design a next‐generation direct current circuit breaker. In this study, the calculation setting for considering the thermal nonequilibrium effect on an electrode surface was established. Moreover, the thermal field theory was employed for simulating the cathode spot movement and a thermal nonequilibrium model was implemented for analyzing the triggering factor of the re‐strike phenomenon occurrence on the anode surface. It was found that heavy particles (ions and neutral particles) were transported forward by the cathode jet and not only caused an increment in the electrical conductivity on the anode surface, but also increased the electric field between the arc column and the anode surface. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Hybrid direct current circuit breakers (DCCBs) have become prominent because of their low on‐state power dissipation and small arc erosion compared with conventional semiconductor and mechanical circuit breakers (CBs). After a fault occurs in a DC circuit, the current commutates from the mechanical contacts to the semiconductor devices of the hybrid DCCB, and finally, the current is interrupted by the semiconductor devices. Thus, a low turn‐on voltage or a low on‐state resistance of the devices is needed to reduce the commutation time and power dissipation of the current interruption. This paper presents a comparison of DCCB performances metrics, such as the maximum interruption current, power dissipation, and junction temperature, using a silicon carbide metal‐oxide‐field‐effect transistor (SiC‐MOSFET) and silicon insulated‐gate‐bipolar transistor (Si‐IGBT) module. An interruption of 1.1 kA was achieved in 4.3 ms using the SiC‐MOSFET module of which rated current was 444 A. The junction temperature after the interruption was determined to be 275°C, which exceeded the maximum junction temperature of 175°C. In the case of the Si‐IGBT module of which rated current was 1110 A, the maximum interrupting current was limited to 900 A; however, the maximum junction temperature was 41°C. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

For realizing the widespread application of fast charging of electric vehicles, a direct current circuit breaker (DCCB) is required to interrupt a large charging current. For developing a next‐generation DCCB that can satisfy this requirement, a three‐dimensional electromagnetic thermal fluid simulation was developed to mimic the interruption process of the DCCB, and an artificial intelligence (AI) model was constructed for differentiating the simulation result. As a result, successful and failed interruption of the DCCB were both simulated, and the constructed AI model successfully differentiated the interruption result and located the extinguish timing of arc plasma in case of a successful interruption. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

To simulate the arc plasma movement and its physical properties during the interruption process of a direct current circuit breaker (DCCB), a numerical method was established in this study for applying recovery voltage during this interruption process considering the molten metal bridge, electrode opening process, and external magnetic field. The results reveal that the re‐strike phenomenon was triggered by either the residue of high‐temperature gas between the electrodes or the rebound flow velocity distribution at the periphery of arc plasma. Furthermore, suggestions for improving the DCCB design are provided herein. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

A high‐voltage direct‐current circuit breaker is a key equipment to construct a flexible direct current transmission system. Most of the existing design schemes have some shortcomings such as slow fault‐breaking speed, poor current‐limiting effect, large capacity of the arrester, and long reclosing operation time. To solve the above problems, this paper proposes an H‐type high‐voltage direct current circuit breaker with a current‐limiting function. The current‐limiting inductance is put into operation by judging the fault condition. It has good current‐limiting ability in the process of fault‐breaking and can maintain the dynamic performance of the power grid in the normal operation of the system. It has the advantages of fast fault‐breaking speed, buffered energy consumption, early separation of fault points, and small capacity of the arrester. During reclosing operation, the transfer branch can be turned on at no‐voltage. The different working states in the process of fault‐breaking are analyzed theoretically based on the description of the topological structure and working principle. Finally, using the PSCAD/EMTDC simulation platform, the functional verification and system verification of fault‐breaking and the reclosing operation process is conducted. Compared with the typical scheme, the simulation analysis shows the effectiveness and applicability of the function of fast fault‐breaking and fault current‐limiting. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]