A novel model of superconducting tape-based hybrid DC circuit breaker for monopolar and bipolar HVDC grid

• In this paper, a new structure of hybrid DC circuit breaker based on superconducting tape called ST-HCB is presented. • The main goals are to improve reliability and reduce costs compared to similar models. ST-HCB. • In this configuration conduction losses and reliability are significantly improved. In this paper, a new structure of hybrid DC circuit breaker based on superconducting tape called ST-HCB is presented, whose main goals are to improve reliability and reduce costs compared to similar superconducting models. ST-HCB, unlike other HCBs, uses thyristor-valves instead of LCS. Therefore, conduction losses and reliability are significantly improved. Since the pre-charged capacitor is utilized for the commutation process and thyristor disconnection, there is no need for a separate energy source to charge the capacitor, and this operation is done through the system itself. Ground resistance is used in the structure of the auxiliary circuit of the capacitor so that it does not affect the system's steady state in charging mode. Also, the placement of the superconducting coils is such that the current is divided between them, the reactor inductance, and the arrester. Thus, the superconducting tape and the arrester do not experience thermal stress. The operation of ST-HCB in different time intervals has been studied through circuit analysis. The correctness of the theoretical analysis is confirmed by evaluating the simulation outputs in COMSOL and PSCAD software.