## 1 Introduction  
Recently, more and more dispersed energy sources, such as photovoltaic solar power and wind power, have been installed into DC systems. More energy power causes higher short-circuit fault currents in DC systems. Traditional methods of limiting short-circuit fault currents in DC systems, such as adding reactors or partition run of the DC system, have great effects on the flexibility and security of the systems [1]. A DC Resistive Type Superconducting Fault Current Limiter (R-SFCL) can significantly improve the stability of DC systems, especially for the high-power DC network, and helpful to reduce the requirement on a DC circuit breaker for interruption time and dissipated energy stress [2; 3; 4; 5; 6; 7; 8]. A resistive SFCL has a simple structure and excellent performance, so it has a great application value for DC fault current limiting technology [9]. The response time of R-SFCL is within 1 ms [5]. When a short-circuit occurs, the quenching resistance increases quickly to limit the fault current to a very low level [6].  
In the normal state, the self-field of superconducting tape coils will influence the critical current of the tapes. [PERSON] considered the influence of the self-field on the critical current of the tapes [10]. [PERSON] said the superconductor's critical current density largely depends on the local magnetic field [11]. [PERSON] studied the magnetic field on the characteristics of YBa2 Cu3O7-\(\delta\) (YBCO) tapes of a Flux-Coupling type SFCL [12]. A lot of researchers have investigated the effects of magnetic fields on the critical current of superconducting tapes. Furthermore, it is not easy for the R-SFCL to achieve a simultaneous quench when the superconducting tapes have in-homogeneities caused by manufacturing imperfections. For that reason, [PERSON] [13], [PERSON] [14] and [PERSON] [15] performed studies to achieve uniform quench distribution with a magnetic field. [PERSON] [16] examined the quench behavior of YBCO bulk elements for AC R-SFCL devices with and without an external magnetic field. The experiments showed that the sample element quenched more homogeneously with the quench assist magnet, even if the sample had inhomogeneity along its length. [PERSON] and [PERSON] [17; 18] investigated the quench behavior of YBCO films under magnetic fields. It was revealed that applied magnetic field could induce simultaneous quenches in all YBCO elements when the fault current limiting units connected in series. [PERSON] [19] applied AC magnetic field to the AC SFCL to get higher resistance only in a current limiting phase. [PERSON] and [PERSON] reported the resistance of the superconducting tapes element and the limiting current capacity of the flux-lock type Superconducting fault current limiter (SFCL) increased by applying the magnetic field into the superconducting tapes' element and adjusting the inductance ratio between the two coils, which was related with the initial limiting current level [20; 21]. [PERSON] applied magnetic fields to high temperature superconducting elements to increase both the resistance of superconducting tapes and the current limiting capacity of the flux-lock type SFCL [22; 23]. Until now, few researchers have investigated the effects of magnetic fields on the quench characteristics of superconducting tapes for DC R-SFCL. However, the studies mentioned above are under AC. Few studies concerned the current limiting properties of superconducting tapes with magnetic fields for DC.  
The objective of this paper is to obtain the effects of static magnetic fields on the quench characteristics of superconducting tapes for DC R-SFCL. Three pairs of permanent magnets were installed between the testing superconducting tapes to generate transverse magnetic fields. The quenched resistance of the superconducting tapes under the transverse magnetic fields of 0, 42.4, 75.9, and 122.9 mT were tested. The magnetic field distribution around the superconducting tapes was simulated by software.