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This paper proposes a analysis of a LED driver. The driver consists of a resonant switched capacitor converter designed to operate in CCM and fed from nanogrid. This mode of operation allows the reduction of current peaks and, consequently, reduction of conduction losses. There is ZVS in the turn-off of the switches due to the full charge and discharge of the switched capacitor. Therefore, switching losses are also reduced. The inductor operates at twice the switching frequency, contributing to the reduction of the magnetic elements. In addition, this converter has the advantage of stabilizing the power of the LED by adjusting the switching frequency, without the needing sensors and control circuit, which reduces the cost of the circuit. In order to validate the comparative analysis, a 10W prototype was designed in a laboratory, operating with a switching frequency of approximately 58 KHz, and presenting an overall efficiency of 92.8% in nominal conditions.

This paper proposes a design and analysis of output filter with long lifetime electrolytic capacitor for a single stage resonant converter based on a switched capacitor for LED driver. A study about conventional capacitors and long life capacitors is presented. Furthermore, the parameters that degrade the electrolytic capacitors lifetime and the effect of current ripple and of LED intrinsic series resistance on the output filter capacitor C o are discussed. Experimental results are presented in order to validate the methodology proposed for the output filter sizing.

This paper presents the LED driver with power factor correction (PFC) and low current harmonic distortion. The structure provides low current ripple, low percent flicker and zero voltage switching (ZVS). The converter output power is varied by reducing the switching frequency, and it does not use electrolytic capacitors (E-cap), what increase the LED driver lifetime. A prototype was developed to evaluate the performance of the proposal, while results are properly presented and discussed. The experimental results presented power factor is 0.996, 3.19% current total harmonic distortion, 9.5% low frequency current ripple and a percent flicker in accordance with the IEEE Std 1789-2015.

This paper presents the evaluation of a single-phase topology and a three-phase topology. Photometric and flicker characteristics were compared. To validate the results, a single-phase charge-pump driver for power LEDs driving a 22 W luminaire, and a three-phase driver with a switched capacitor was used for power LEDs driving a 216 W luminaire. The obtained results were compared with the actual norms. The three-phase driver is operating within the recommended operating region in Std. 1789-2015, while the single-phase driver is operating outside the recommended region.

This paper presents a dimmable charge-pump driver to power light-emitting diodes (LEDs) with power factor correction (PFC) and Zero Voltage Switching (ZVS). The proposed LED driver does not utilize electrolytic capacitors, providing a high useful lifetime, and it can stabilize the output current in open loop control without needing current sensors, which reduces the cost. The output power is proportional to the switching frequency, which allows the LEDs dimming. A prototype with 22 W was implemented and experimental results were discussed. The prototype presented a power factor of 0.996 and an efficiency of 89.5 %. The driver output power was reduced by more than 40% through the switching frequency while varying of 53 kHz to 30 kHz and the converter has continues to operate in ZVS.

This paper presents a switched capacitor-based converter to drive high power light emitting diodes (LEDs). Unlike the traditional switched capacitor based one, the proposed converter uses an inductor to avoid the forced charging and discharging operation reducing stress current in circuit. The proposed converter provides inherent power factor correction (PFC) and the switched capacitors are used as isolation capacitors. The proposed converter also uses a LC filter to reduce the output current ripple through LED array instead using a bulk electrolytic capacitor. The basic description of the topology is presented and a laboratory prototype of 48 W has been implemented. The experimental results presented demonstrate the technical feasibility of the proposed converter applied as LED driver.

This paper proposes a resonant switched capacitor-based converter to driver high power light emitting diodes (LEDs). Unlike the traditional switched capacitor based one, the proposed converter uses an inductor to avoid the forced charging and discharging operation reducing stress current in circuit. The proposed converter provides inherent power factor correction (PFC) and the switched capacitors are used as isolation capacitors. The basic description of the topology is presented and a 49 W, 220 V ac grid laboratory prototypes has been implemented. The experimental results presented demonstrate the technical feasibility of the proposed converter applied as LED driver.