ABSTRACT:

The authors have investigated the effect of thermal cycling on the output intensity, peak position and chromaticity coordinates of a high-power AlGaInP light-emitting diode (LED) driven under pulse-width modulation (PWM; pulse width of 200 s to 20 ms at a constant repetition frequency of 50 Hz) and pulse-frequency modulation (PFM; repetition frequency of 50 5000 Hz at a constant pulse width of 200 s) modes. Experimental data on the junction temperature oscillation were obtained by using the transient forward voltage method and accounted for by a thermal model of a repetitive-pulse-driven LED with multi-exponent relaxation of the junction temperature. Compared to the PWM driving mode, the PFM mode, which causes a reduced junction temperature oscillation, was shown to offer an efficiency gain (5 at a 50 duty cycle) and a reduced non-linearity of output characteristics (deviation of the output intensity dependence on duty cycle from a self-heating-free one, as well as electroluminescence (EL) band peak position and chromaticity coordinates dependences on duty cycle). Based on the results of the investigation, the PFM driving mode is suggested as an advantageous alternative for controlling polychromatic LED clusters by temperature feed-forward compensation loops and dimming LEDs in lighting applications.


Did you like this research project?

To get this research project Guidelines, Training and Code... Click Here


PROJECT TITLE : Impact of Cell Association on Energy-Efficiency and Hit Rate of Femto-Caching ABSTRACT: The user experience is improved thanks to the caching of content at femto base stations (F-BSs). In actuality, the amount
PROJECT TITLE : Multiview Subspace Clustering With Grouping Effect ABSTRACT: Multiview subspace clustering, also known as MVSC, is a relatively new method that was developed with the intention of finding the underlying subspace
PROJECT TITLE : Impact of Wireless Energy Transfer Strategies on the Secrecy Performance of Untrustworthy Relay Networks ABSTRACT: The purpose of this study is to investigate the performance of a dual-hop relaying network that
PROJECT TITLE : Impact of Block Data Components on the Performance of Blockchain-Based VANET Implemented on Hyperledger Fabric ABSTRACT: The way in which we share, manage, and trade our data has shifted from a centralized to
PROJECT TITLE : Impact of Block Data Components on the Performance of Blockchain-based VANET Implemented on Hyperledger Fabric ABSTRACT: The way in which we share, manage, and trade our data has shifted from a centralized to

Ready to Complete Your Academic MTech Project Work In Affordable Price ?

Project Enquiry