A buck‐boost integrated high gain non‐isolated half‐bridge series resonant converter for solar PV/battery fed multiple load LED lighting applications

Abstract

Summary Solar photovoltaic (SPV) or battery fed multiple load LED lighting applications are gaining importance these days, which require independent voltage regulation and dimming control. Half‐bridge resonant converters are mostly used due to their simple structure. In this paper, a buck‐boost integrated high gain non‐isolated symmetrical half‐bridge series resonant converter is proposed for multiple load LED lighting applications. With the aid of integrated buck‐boost operation, the output voltage can be regulated below and above the nominal input voltage effectively and can produce twice the gain as compared with classical half‐bridge converters. Frequency modulation is implemented for output voltage regulation. Pulse width modulation (PWM) dimming has been adopted for illumination control. The proposed driver results in several advantages such as low cost, compact size, improved efficiency due to soft‐switching, simple control, independent dimming, and effective operation for multiple loads. Thus, the proposed non‐isolated driver configuration is well suited for SPV/battery fed multiple load LED lighting applications. The proposed configuration is tested with single LED load of 22 W and dual‐LED loads of 22 W and 43 W. There is an excellent consensus between the simulation and the experimental outcomes.

Electrical model formulation for multicolor light‐emitting diode modules and its application to design dimmable driver

“…The design of LED drivers for modules made of LED chips of same type can be found in the literature. [2][3][4][5][6][7] However, none of the existing works present the design methodology for multicolor LED modules, which are relevant nowadays for color-tuning applications of lighting. Moreover, in most of the existing works, designers consider the linear model, which fails to reproduce the entire electrical characteristics of a real LED.…”

“…1 A number of LED devices are fabricated in a module in series-parallel combination to realize the desired lumen output. 2,3 In most of the functional indoor and outdoor lighting applications, LED chips of same type or spectral composition are fabricated in a module. Electrical modeling of such modules is available in the existing works, [4][5][6][7] some of which are specifically applied in various applications such as (i) design and analysis of LED drivers, (ii) optimum sizing of the LED array, and (iii) design of string current-balancing elements.…”

“…Electrical characteristics of LED can be simulated using any one of the (i) linear, [2][3][4]7,14 (ii) parabolic, 1,15 (iii) exponential, [16][17][18] and (iv) modified Shockley 5,6,19 model. The corresponding model equations for a single LED chip are given below in 1-4.…”

“…Recent LED driver prototypes attempt to incorporate dimming feature for the sake of power-saving and task-tuning. 2,3,20 As the average forward current is reduced under dimming condition, the electrical operating point of the LED may get shifted to the nonlinear region. 21 In this nonlinear region, the linear model produces unacceptably higher deviations from the practical data 5 and therefore is considered invalid.…”

“…Design and analysis of such drivers for modules made of LED chips of same type or color can be found in the literature. 2,7 However, none of these existing works considers multicolor LED module as the electrical load of the driver. In the present work, multicolor (R-G-B) LED modules bearing both conventional and nonconventional configurations are taken into account.…”