A direct battery-driven LED lighting technique using constant-power control is proposed in the present study. A system dynamics
model of LED luminaire was derived and used in the design of the feedback constant-power control system. The test result has shown
that the power of 18 W and 100 W LED luminaires can be controlled accurately with error at 2–5%. A solar LED street lighting system
using constant-power and dimming control was designed and built for field test in a remote area. The long-term performance was satisfactory
and no any failure since the installation. Since no high-power capacitor is used in the present constant-power control circuit, a
longer lifetime is expected.