Method of delivering a diffuse duty cycle
US6028416A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 30, 1998 |
| Grant date | Feb 22, 2000 |
| Priority date | — |
| Expiry date | Sep 30, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/92
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for controlling the duty cycle of a pulse width modulated (PWM) output signal applied to a field winding of an alternator of a motor vehicle. The PWM signal is generated from a controller associated with a vehicle engine to control the output current from a vehicle alternator during engine operation. The method involves determining a desired duty cycle for the PWM signal to be applied to the field winding of the alternator. The method then involves determining the PWM signal's "ON" and "OFF" pattern to deliver the desired duty cycle. This is accomplished by adding the value corresponding to the desired duty cycle to a running sum value. The PWM signal to the alternator is turned "ON" if the new running sum value exceeds or is equal to 100. One-hundred is then subtracted from the running sum value before it is stored. However, if the new running sum value is less than 100, then the PWM signal is turned "OFF" and the new running sum value is then stored without subtracting 100. On the next cycle, the desired duty cycle is again added to the presently stored running sum value to produce a new value which is again checked to determine if it is greater than or equal to 100, and…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.