Redução da capacitância de barramento em driver para alimentação de leds

Abstract

This work presents the contextualization, problem definition and LED driver solution reducing the effect of circuit bus capacitance. Through the active control of the driver output current, the ripple from the PFC stage of the current can be controlled, keeping it at levels appropriate to the technical standards, being IEC 61000-3-2 Class C and IEEE 1789. This control allows the output voltage ripple to vary at higher amplitude levels, allowing the use of a lower capacitance bus capacitor and longer life. An analysis of the Buck-Boost converter was performed at the power stage for different bus voltages and output power. Analyzing cases where different controllers were applied, in order to obtain an analysis of the influence of these controllers in the reduction of bus capacitance. Thus obtaining a greater ripple in the bus voltage, ensuring to meet the IEEE 1789 standard.