TY - JOUR
T1 - Self-Configurable Current-Mirror Circuit With Short-Circuit and Open-Circuit Fault Tolerance for Balancing Parallel Light-Emitting Diode (LED) String Currents
AU - Li, Sinan
AU - Hui, S. Y. Ron
PY - 2014/10/1
Y1 - 2014/10/1
N2 - Current imbalance among parallel light-emitting diode (LED) strings could put excessive current and thermal stress on some of the LEDs in the systems, resulting in reduction in system lifetime. For LED road lighting systems, reliability is the paramount factor. This paper first explains how existing current-mirror (CM) circuits cannot cope with LED open-circuit faults and then describes a self-configurable CM circuit that can withstand open-circuit faults in LED systems with parallel LED strings. The ability to withstand open-circuit faults means that the LED systems can still function with reduced luminous output even if one LED string is cut off. The proposed circuit, which retains the feature of not requiring an auxiliary dc power supply, has been practically implemented and successfully tested in a 70-W LED system with three parallel strings
AB - Current imbalance among parallel light-emitting diode (LED) strings could put excessive current and thermal stress on some of the LEDs in the systems, resulting in reduction in system lifetime. For LED road lighting systems, reliability is the paramount factor. This paper first explains how existing current-mirror (CM) circuits cannot cope with LED open-circuit faults and then describes a self-configurable CM circuit that can withstand open-circuit faults in LED systems with parallel LED strings. The ability to withstand open-circuit faults means that the LED systems can still function with reduced luminous output even if one LED string is cut off. The proposed circuit, which retains the feature of not requiring an auxiliary dc power supply, has been practically implemented and successfully tested in a 70-W LED system with three parallel strings
UR - https://ieeexplore.ieee.org/abstract/document/6670759
U2 - 10.1109/TPEL.2013.2291392
DO - 10.1109/TPEL.2013.2291392
M3 - Article
SN - 0885-8993
VL - 29
SP - 5498
EP - 5507
JO - IEEE Transactions on Power Electronics
JF - IEEE Transactions on Power Electronics
IS - 10
ER -