A Review of LED Driver Topologies and Control Methods for Energy-Efficient Smart Farming Application

In order to feed the ever-increasing global population, current food production must increase significantly in the near future. Increasing food production by expanding farmland or by farming intensification would lead to increasing land-use demand, which comes at the cost of biodiversity, increasing pressure on vulnerable ecosystems, and requiring large volumes of water and mineral fertilizer. Smart farming has been identified as an emerging solution to help address the need for increasing food production without an increase in land-use demand. In smart farming, crops are grown in vertical arrangements using artificial lighting and are fed hydroponically using nutrient solutions. With greatly improved water and nutrient use efficiency, it has been demonstrated that increases in crop yield and quality can be achieved by manipulating the properties, such as photoperiod, wavelength, and intensity of the artificial light through the use of light-emitting diodes (LEDs). LEDs require DC power supply, whereas the electric grid generates AC power, thereby requiring an LED driver to convert AC to DC power. Energy-efficient LED drivers can significantly reduce the operational cost of smart farming. This chapter presents a review of power electronic circuits and their control methods for driving LEDs from the grid. First, a short summary of the conventional circuit topologies is presented. Then, different control methods are critically reviewed. Finally, some potential research directions are provided to enhance the efficiency of LED drivers through control system improvement. The review presented in this chapter will assist researchers in making informed decisions when choosing or designing LED circuit topologies and control methods to improve the overall energy efficiency in smart farming systems.