Investigation of the three-phase heat pump drying system's impact on power quality of the electrical grid

Abstract

In this study, the impact of an experimentally designed Heat Pump Drying (HPD) system on the electrical grid was evaluated. For this purpose, eggplant slices were dried in the experimental HPD system under controlled humidity and temperature conditions. In the HPD system, condenser of heat pump and an external electric heater with a power rating of 550 W were placed at the inlet of the drying chamber. A controller was used in the drying chamber to maintain a constant air temperature of 35 °C and humidity levels between 20% and 40%. This controller effectively activated the compressor and the external heater individually or in groups to achieve the desired drying conditions. Throughout the experiment, a Fluke 435 II power analyzer was employed to examine the impact of the HPD system on the electrical grid. Parameters such as active power, reactive power, power factor, displacement power factor, harmonics, imbalances, and energy consumption were recorded for the system. The obtained data were analyzed in accordance with energy quality standards, and issues were identified. Suggestions for improving the energy quality of the system were subsequently proposed.