Patent · US Expired

AC Motor-starting for aircraft engines using APU free turbine driven generators

US4456830A · kind A · utility

65Cited by
2References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 22, 1982
Grant dateJun 26, 1984
Priority date
Expiry dateApr 22, 2002

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF05B2220/50
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

The invention is an electric starting system for starting aircraft jet engines (32), (34) and (36) using an APU (10) free turbine driven generator (12). The operating power factor of the starter-generator (12) is controlled during start mode operation of the APU (10) by monitoring the line current via a current transformer (58). Contactors (14) and (16) connect the generator (12) into the aircraft's ac power system and ac starting system, respectively. A master start relay (22) is provided, and is closed in the `start` mode such that a power electronics inverter (24) may be powered from external power via contactors (18). The variable-voltage/variable-frequency output of inverter (24) is controlled via a logic controller (26) and can be applied sequentially to the three engine driven generators (32), (34) and (36) via start relays (42), (44) and (46) to start the engines (32), (34) and (36) respectively. An alternative embodiment of the APU generator/power electronics/starter-generator start system is the utilization of a separate induction motor starter than can operate with or without the use of power electronics.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.