Feasibility of a Power and Control System for an Autonomous Photovoltaic Hot Plate Type Cooker (600 Wp)

This chapter provides the experimenting, results, and findings related to the design of a new autonomous solar cooking using photovoltaic energy. The proposed architecture is composed of a PV panel of 600 W/peak, a power bloc containing a DC/DC boost converter, a load in the form of two identical heating plates, and a control bloc to supervise the system, collect, and display the electrical quantities. A 20 kHz PWM signal is used to control the boost with a variable duty cycle. The variation of duty cycle is realized either manually via an analog circuit or automatically via a digital circuit built around the Raspberry Pi Pico microcontroller. The microcontroller is also responsible for the acquisition and display of the electrical quantities (voltage, current, power, efficiency, etc.). The irradiation and ambient temperature are retrieved from a meteorological station in real time. Also, to prevent the malfunction caused by open load problems, we added a switch to cut the line in case of any fault detected problem. The results for both analog and digital control circuits are presented, and experimentation on boiling, respectively, 1 L of water and ½ liter of oil is done. For irradiation between 400 W/m2 and 820 W/m2, and an ambient temperature of around 24 °C, the proposed system delivers an output power reaching 310 W with an efficiency of up to 95%. The experience with heating water and oil shows that the temperature increases rapidly and attains a boiling temperature of 98 °C in just 25 min in the case of water, and a temperature of 239 °C in 20 min in the case of oil. Comparing our system to other existing architecture shows an improvement in efficiency, maximum temperature, and heating speed, which proves its feasibility in both rural and urban households.