1
Jooyeong So 1 , Seyeon Lee 1 , Woo-Seok Kim 1 , Ji-Kwang Lee 2 , Kyeongdal Choi 1 1: Korea Polytechnic University, 2: Woosuk University Design of an HTS Fault Current Limiting Module for an MVDC Power Grid 1. Introduction Thu-Mo-Po4.11-07 [80] We have studied a DC circuit breaker with an HTS fault current limiting module for an MVDC power grid. Among several 2G REBCO conductors from different suppliers, we selected the most suitable conductor based on the short circuit tests with sample conductors. A stabilizer-free REBCO conductor was chosen for a fast reaction to the fault current. A design work for an MVDC class FCL module was carried out and verified by simulation. 2. SFCL for DCCB 0 5 10 15 20 25 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 300 [K] Resistance [Ohm/m] Time [ms] 50[V/m] 45[V/m] 40[V/m] 35[V/m] 30[V/m] 25[V/m] 20[V/m] 0 5 10 15 20 25 0.00 0.05 0.10 0.15 0.20 0.25 0.30 Resistance [Ohm/m] Time [ms] 50[V/m] 45[V/m] 40[V/m] 35[V/m] 30[V/m] 25[V/m] 20[V/m] 300 [K] 0 5 10 15 20 25 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Resistance [Ohm/m] Time [ms] 50[V/m] 45[V/m] 40[V/m] 35[V/m] 30[V/m] 25[V/m] 300 [K] 0 5 10 15 20 25 0.00 0.05 0.10 0.15 0.20 0.25 0.30 300 [K] Resistance [Ohm/m] Time [ms] 150[V/m] 145[V/m] 140[V/m] 135[V/m] 130[V/m] 125[V/m] 120[V/m] 115[V/m] 110[V/m] 105[V/m] 0 5 10 15 20 25 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 300 [K] Resistance [Ohm/m] Time [ms] 150[V/m] 145[V/m] 140[V/m] 135[V/m] 130[V/m] 125[V/m] 120[V/m] 115[V/m] 110[V/m] 105[V/m] 100[V/m] We prepared the DC overcurrent test system with a supercapacitor of 500 F for the short circuit test with the selected sample HTS conductors. The maximum applied voltage on the supercapacitor was 14 V, which generated the fault current of 1,750 A. The sample HTS conductors were attached on the FRP holder and immersed in the liquid nitrogen vessel for the short circuit test. 4. DC overcurrent test system 5. Overcurrent test Result 3. 2G HTS sample conductors 6. Design of fault current limiting module The amount of the stabilizer will affect the resistivity of the HTS conductor, so that it will define the general performance of the HTS fault current limiting module and the total amount of the HTS conductor. We selected five different kind of the HTS conductors to be tested for their overcurrent performances. A resistive type HTS current limiting module in series to the DCCB would reduce the burden of the DCCB when the fault occurs. 7. Conclusion (a) AMSC 4 mm (b) AMSC 12 mm (b) Superpower 12 mm (b) SuNAM 12 mm (b) SuNAM(SF) 12 mm [ Fig. 1. Circuit diagram of the DC circuit breaking system with an SFCL module ] [ TABLE I. Specifications for each conductor ] [ Fig. 2. Cross-section diagrams of each sample HTS conductor ] [ Fig. 3. DC overcurrent test system ] [ Fig. 4. circuit of the test system ] [ Fig. 6. HTS sample and holder ] [ Fig. 7. Overcurrent test result for the HTS samples] [ Fig. 8. non-inductive bifilar coil ] [ TABLE II. DC circuit breaker for FCL ] [ TABLE III. SFCL module design parameters ] [ TABLE IV. Design parameters of SFCL module with non-inductive bifilar coil] [ Fig. 9. simulated fault current limitation in 15 kV DC grid] [ Fig. 10. Magnetic field calculation for the HTS FCL module ] A resistive type SFCL module to reduce the burden of a 15 kV class DC circuit breaker was designed with various kind of 2G REBCO conductors and the current limiting performance was verified by simulation. The SFCL module with Stabilizer-free HTS conductor shows faster reaction to the fault current and shorter duration time. A scale-down SFCL module will be fabricated and tested in near future.
![Page 1: [ TABLE III. SFCL module design parameters ] Time [ms] · A resistive type SFCL module to reduce the burden of a 15 kV class DC circuit breaker was designed with various kind of 2G](https://reader035.documents.pub/reader035/viewer/2022071502/612226cadc3b1b5e0412a343/html5/thumbnails/1.jpg)
