No output from primary hampering power source(s). mission goal(s). Internal failure in DCLL. 3 Faulty or Faulty power output from at Cannot High Similar reasoning to case-1. Further, faults in – inadequate least one DCDC device. operate the PEC (in this case DC-AC converter device) of power input ACLL and zones may cause disturbances within its zone Power quality issues in DC to ACLL. may affect (propagation of fault to busses and in turn other zones busses. achieving is evaded owing to isolation provided by the DCDC Internal fault with DCDC mission devices) owing to factors such as switching harmonics device. objective. because of the added DC-AC inversion. Faulty power output from ACDC devices. Faulty power output from primary power source(s). Faulty power output from DCAC device. Internal fault in ACLL. 4 No power No power output from at Cannot High Similar reasoning to case-2 with respect to – input to least one DCDC device. operate inability of being able to operate ACLL for a particular ACLL No power flow in DC ACLL and mission. very likely busses. that entire Internal fault with DCDC zone is devices. without No power output from ACDC devices. No power output from primary power source(s). No power output from DCAC device. Internal failure in ACLL. Table : DC power ring F-FMEA DC ring subsection Function: To provide continuous power at required rating and quality to DC busses. Constituents: MTG1, MTG2, ATG1, ATG2, ACDC_P_MTG1, ACDC_S_MTG2, ACDC_P_ATG1, ACDC_S_ATG2, DCD No. Constituent Quantity Type devices (general) 1 MTG 2 Primary power source 2 ATG 2 Primary power source 3 ACDC 4 Power delivery device (specific PEC) No. Failure Cause Effect Severity and remarks mode 1 Faulty Faulty or Faulty High System wide issue which would have – inadequate and and loads. output input to DC from bus. quality ACDC power device flow in due to DC internal busses. fault. Faulty power output from primary power source(s) due to internal fault.
hampering mission goal(s). No output from primary power source(s). Internal failure in DCLL. 3 Faulty or inadequate power input to ACLL. Faulty power output from at least one DCDC device. Cannot operate ACLL and may affect achieving mission objective. High – Similar reasoning to case-1. Further, faults in the PEC (in this case DC-AC converter device) of zones may cause disturbances within its zone (propagation of fault to busses and in turn other zones is evaded owing to isolation provided by the DCDC devices) owing to factors such as switching harmonics because of the added DC-AC inversion. Power quality issues in DC busses. Internal fault with DCDC device. Faulty power output from ACDC devices. Faulty power output from primary power source(s). Faulty power output from DCAC device. Internal fault in ACLL. 4 No power input to ACLL No power output from at least one DCDC device. Cannot operate ACLL and very likely that entire zone is without High – Similar reasoning to case-2 with respect to inability of being able to operate ACLL for a particular mission. No power flow in DC busses. Internal fault with DCDC devices. No power output from ACDC devices. No power output from primary power source(s). No power output from DCAC device. Internal failure in ACLL. Table : DC power ring F-FMEA DC ring subsection Function: To provide continuous power at required rating and quality to DC busses. Constituents: MTG1, MTG2, ATG1, ATG2, ACDC_P_MTG1, ACDC_S_MTG2, ACDC_P_ATG1, ACDC_S_ATG2, DCD No. Constituent devices (general) Quantity Type 1 MTG 2 Primary power source 2 ATG 2 Primary power source 3 ACDC 4 Power delivery device (specific PEC) No. Failure mode Cause Effect Severity and remarks 1 Faulty or inadequate input to DC bus. Faulty output from ACDC device due to internal fault. Faulty and quality power flow in DC busses. High – System wide issue which would have and loads. Faulty power output from primary power source(s) due to internal fault.