Abstract
It is sometimes unavoidable to have light-emitting-diode (LED) light sources and their pulsewidth modulation (PWM) drivers connected by long cables in large-scale illuminations. However, long-cable inductance delays the rate of rise of the driving current pulses and thus leads to the reduction of luminous flux output. It also causes the off-state voltage across the light sources negative, which would deteriorate the life expectancy of the LEDs. A switched-capacitor-based current compensator for correcting the wave shape of the driving current pulses is presented. The methodology is based on transferring the energy stored in the cable to a capacitor at the end of the current pulse and then momentarily boosting the voltage with the capacitor applying to the cable at the beginning of the next current pulse. Thus, the rise time of the current pulses can be shortened. The topological states and operations of the compensator will be described. A simplified design procedure will be given. A prototype for a 12-V, 3-A PWM driver has been built and evaluated. Performance comparisons between the proposed current compensator and prior art and between the systems with and without the compensators will be conducted.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
