Study on safety performance evaluation of stationary SOFC stack

건물용 고체산화물연료전지 스택 안전성능평가 연구

Abstract

The code and standards related to fuel cells were analyzed to derive the SOFC(Solid Oxide Fuel Cell) stack safety performance evaluation items and evaluation methode. Safety performance evluation of the SOFC stack was tested by quoting derived test items. The stack used in the test is an anode-supported type 2 Cell stack (Active surface area : 220cm) manufactured by MICO Inc, and SOFC stack safety performance evaluation system used for the test is self-manufactured. We conducted a leakage test, current voltage characteristic test, rated output test, and power response characteristics test. In the safety performance evaluation test, the stack showed no gas leakage, the maximum output and rated output was recorded to 65.6 W(1.41 V, 46.5 A, $422mA/cm^2$), 62.3 W(1.57 V, 40 A, $363mA/cm^2$). In the power response characteristics test verified that the output is kept stable within two seconds. At the maximum load (40 A) and the minimum load (8 A), the output was recorded 62 W and 16W in $750^{\circ}C$. This study will contribute to the universalization and to provide much safe environment of operating the solid oxide fuel cell system.

SOFC (Solid Oxide Fuel Cell) stack 안전성능 평가항목 및 평가절차 도출을 위하여 국내 외 연료전지 관련 규격들을 분석하였으며, 분석을 통해 도출된 시험항목으로 SOFC stack 안전성능 시험을 실시하였다. 시험에 사용된 SOFC stack은 (주)미코사(社)에서 제작된 음극 지지형 2 cell stack(활성면적: $110.25cm^2/cell$)이고, 평가장치는 자체 제작한 SOFC stack 안전성능 평가 장치를 사용하였다. 기밀성능 시험, 전류전압특성 시험, 정격출력 시험 및 부하변동 시험을 실시하였으며, 그 결과 해당 stack의 최대출력은 65.6 W(1.41 V, 46.5 A, $422mA/cm^2$), 정격출력은 62.3 W(1.57 V, 40 A, $363mA/cm^2$)로 나타났으며 가스누출이 없음을 확인하였다. 또한, 부하변동에 대하여 2초 이내에 안정적으로 출력이 유지되는 것을 확인하였다. 이때 운전 온도 $750^{\circ}C$에서 최대부하(40 A) 및 최소부하(8 A)에서의 출력은 각 62 W와 16 W로 측정되었다. 본 연구를 통하여 고체산화물연료전지의 보급화와 안전한 사용 환경을 제공하는데 기여하고자 한다.

Fig. 1. SOFC stack safety performance evaluation system

Fig. 2. SOFC stack safety performance evaluation system P&ID flowchart

Fig. 3. SOFC 2 cell stack

Fig. 4. Leak test for SOFC 2 cell stack

Fig. 5. I-V test for SOFC 2 cell stack

Fig. 6. Rated output test for SOFC 2 cell stack

Fig. 7. Power response characteristics test for SOFC2 cell stack

Table 1. Comparing installation area of solar, wind and fuel cells

Table 2. Types of fuel cells according to operating temperature

Table 3. The list of solid oxide fuel cell codes and standards

Table 4. SOFC stack test items by stage

Table 5. Test operation condition by stage-1

Table 6. Test operation condition by stage–2

Table 7. Test operation condition by stage–3-1

Table 8. Test operation condition by stage–3-2

Table 9. Operation condition of SOFC stack