The need for efficient power transfer at lower cost is a common requisite for any power con­verter system. When considering the application of wireless power transfer for Electric Vehicle(EV) charging, higher efficiency and lower cost can be achieved by reducing the number of stages of the system at the grid side. This thesis explores the feasibility of an AC/AC matrix converter for wireless power transfer application. To begin with, different existing topologies of the converter module are discussed and qualita­tively compared to the matrix converter. Subsequently, the plausibility of single stage matrix converter is verified through simulation. Due to the converter’s high switching frequency, this configuration results in injection of higher than permitted harmonic content into the grid. Fur­thermore, the feasibility of three phase matrix converter and its advantages are studied. The converter working is verified through simulation. To make the grid current less distorted, closed­ loop control is introduced. This control con­sists of an inner current loop and an outer voltage loop which are both implemented using a PI controller. To conclude, three phase matrix converter acts as a plausible solution for the desired applica­tion. Furthermore, the control ensures balanced grid current and desired output power.

The effectiveness of ultraviolet (UV) irradiation for disinfection has been well-known for more than a century. Recent advances in light­-emitting diode (LED) technology have brought UV LEDs to the consumer market. These offer many advantages over traditional gas­-discharge lamps, allowing UV radiation to be generated with higher reliability in a much smaller form factor. In this thesis, the design of a portable battery­-powered sterilizer based on UV LEDs is described. The sterilizer is intended for the sterilization of personal items such as mobile phones, face masks, and keys.

The design of the sterilizer consisted of two parts: the LED array and the LED driver. For their design, a model­-based approach was taken to ensure high performance and low cost. For the LED array, a radiometric model was developed and applied in an optimization procedure. The design of the LED driver was based on an analytical loss model in MATLAB and LTspice simulations.

The UV LED array provides a radiant power of 113 mW to the disinfection area, resulting in an irradiation dose of 195 μW/cm2. This allows for more than 99.9% disinfection in less than 15 min. The LED driver is a boost converter operating at 750 kHz in the discontinuous conduction mode. This converter supplies the array with a nominal input power of 4.3 W at a simulated efficiency of 91%.

The design of the LED driver is verified with a prototype. Measurements show efficiencies around 83% at 4.1 W output power. Incorporating several improvements over the prototype, efficiencies between 85–87% can be expected for the LED driver in the sterilizer.