High power permanent magnet alternator with improved controlled output
Apparatus, systems, and methods are provided for reducing a potentially damaging high voltage fault condition in an alternator system. The apparatus comprises a motor, a rectifier coupled to the motor, an output node coupled to the rectifier, and a switch coupled between the rectifier and the output node, wherein the switch is a normally “on” switch. The system includes the apparatus implemented into a vehicle comprising an engine to drive the apparatus and a battery coupled to the apparatus, wherein the apparatus provides current to the battery. The method includes the steps of providing current from a rectifier of the alternator to a battery coupled to the rectifier and ceasing to provide current to the battery if a damaging event occurs, wherein the ceasing step comprises the step of switching OFF a normally “on” switch coupled between the rectifier and the battery if a damaging event occurs.
1. An alternator system, comprising:
a motor;
a rectifier coupled to the motor;
an output node coupled to the rectifier;
a switch coupled between the rectifier and the output node, wherein the switch is a normally ON switch configured to switch OFF and to thereby prevent current from the rectifier from flowing to the output node in response to a damaging event; and
a battery coupled to the output node, wherein the rectifier ceases to provide current to the battery if a damaging event occurs by switching OFF the switch.
2. The alternator system of claim 1 , wherein the motor is a permanent magnet motor.
3. The alternator system of claim 2 , wherein the switch is a semiconductor device.
4. The alternator system of claim 3 , wherein the semiconductor device is a junction gate field effect transistor (JFET).
5. The alternator system of claim 4 , wherein the silicon-based semiconductor device is a silicon carbide JFET.
6. The alternator system of claim 2 , wherein the alternator is an inverterless high power PM alternator.
7. A vehicle, comprising:
an engine;
an alternator coupled to the engine, wherein the alternator comprises:
a permanent magnet motor,
a diode rectifier coupled to the motor, and
a switch coupled to the rectifier, wherein the switch is a normally ON switch; and
a battery coupled between the rectifier and the switch.
8. The vehicle of claim 7 , further comprising:
a 42 volt electrical system coupled to the alternator, wherein the alternator provides power to the 42 volt electrical system.
9. The vehicle of claim 7 , further comprising:
a 12 volt electrical system coupled to the alternator, wherein the alternator provides power to the 12 volt electrical system.
10. The vehicle of claim 7 , wherein the switch is a semiconductor device.
11. The vehicle of claim 10 , wherein the semiconductor device is a junction gate field effect transistor (JFET).
12. The vehicle of claim 11 , wherein the silicon-based semiconductor device is a silicon carbide JFET.
13. The vehicle of claim 7 , wherein the switch is configured to be OFF if at least one of an error and a failure occurs.
14. A method to reduce a potentially damaging high voltage fault condition in an alternator system, comprising the steps of:
providing current from a rectifier of the alternator to a battery coupled to the rectifier; and
ceasing to provide current to the battery if a damaging event occurs, wherein the ceasing step comprises the step of:
switching OFF a normally on switch coupled between the rectifier and the battery if a damaging event occurs.
15. The method of claim 14 , wherein the ceasing step comprises the steps of:
ceasing to provide current to the battery; and
providing current through the switch instead of to the battery if a control error occurs.
16. The method of claim 14 , wherein the ceasing step comprises the steps of:
ceasing to provide current to the battery; and
providing current through the switch instead of to the battery if a switch failure occurs.
17. The method of claim 14 , wherein the switching OFF step comprises:
switching OFF a normally on semiconductor device such that current flow through the switch instead of to the battery.
18. The method of claim 14 , wherein the switching OFF step comprises:
switching OFF a normally on junction gate field effect transistor (JFET) such that current flow through the switch instead of to the battery.
19. The method of claim 14 , wherein the switching OFF step comprises:
switching OFF a normally on silicon carbide JFET such that current flow through the switch instead of to the battery.