Integrated brushless starter generator
View Patent ↗A brushless starter-generator system is contained within a single housing. The housing has a first end with an opening to receive a drive spline from a motive source and an opposing second end. A brushless, rotating machine is located adjacent the first end and is kinetically connectable to the drive spline. A power control unit is adjacent the second end and electrically coupled to the brushless, rotating machine. The brushless, rotating machine is selected from the group consisting of a synchronous machine, a permanent magnet machine, and an induction machine. Electrical and mechanical interfaces are identical to a like-rated brushed version for a true “drop-in” replacement capability to facilitate replacements and up-grades.
1. A starter-generator system contained within a single housing disposed within a nacelle of an aircraft, the starter-generator system comprising:
said housing having first and second ends, wherein the first end includes a first end opening to receive a drive spline from a motive source, and wherein the second end includes a second end opening that is opposite the first end, the second end opening terminating at an air inlet duct;
a brushless starter-generator unit adjacent the first end and kinetically connectable to the drive spline; and
a power control unit adjacent the second end and electrically coupled to the brushless starter-generator unit, the power control unit including
a terminal block configured to transmit DC electrical power to and from the starter-generator; and
a field effect transistor module interconnecting the terminal block and a circuit card assembly configured to provide timing signals to the field effect transistor module;
wherein in a start mode, the power control unit receives DC power via the terminal block, controls the FET module to invert the DC power to AC power at timing controlled by the circuit card assembly, and supplies the AC power to the starter-generator unit, and in a generate mode, the power control unit rectifies AC power received from the starter-generator unit to DC power and provides the DC power via the terminal block.
2. The starter-generator system of claim 1 , wherein the brushless starter-generator unit is a brushless rotating machine that is selected from the group consisting of a synchronous machine, a permanent magnet machine, and an induction machine.
3. The starter-generator system of claim 2 , wherein the motive source is a turbine engine or a piston engine of an aircraft.
4. The starter-generator system of claim 2 , wherein the brushless rotating machine is synchronous, wherein the power control unit is used primarily in the start mode to motor the engine, and wherein the power control unit is used in the generate mode to synchronously rectify the AC output to DC for maximum rectification efficiency.
5. The starter-generator of claim 2 , wherein the housing has external electrical and mechanical interfaces and physical proportions similar to those of a brushed starter-generator for small to medium size aircraft.
6. The starter-generator of claim 5 , wherein the power control unit components are contained within environmentally sealed compartments within the housing for effective protection against the elements.
7. The starter-generator of claim 6 , wherein a set of major heat producing components of the power control unit are connected to a heatsink placed in line with a cooling airstream, for effective cooling while protected from the environments.
8. The starter-generator system of claim 5 , said starter-generator system configured to be deployed as a true drop-in replacement for a like-rated brushed starter-generator, wherein the housing has a substantially barrel shape, with a nominal outside diameter of 6 inches, the barrel diameter tapering at the second end to be approximately 3 inches in diameter at the air inlet duct, and a length, exclusive of the air inlet duct, of approximately 11 inches.