Adaptive compressor speed control of photovoltaic-driven air conditioner: Operational characteristics, system performance, and economic analysis

Photovoltaic-driven Air Conditioner (PVAC) systems suffer from a dynamic mismatch between Photovoltaic (PV) generation and Air conditioner (AC) consumption power. To address this challenge and investigate the potential in achieving carbon neutrality, this study proposed an adaptive control method for a PVAC system. An experimental facility and a numerical model were developed. This paper evaluated the energy characteristic and decarbonization potential of the system using four evaluation indices: the Self-Satisfy Ratio, Self-Consumption Ratio, Net Present Value, and Levelized Cost of Carbon Abatement. The results showed that the adaptive control system could effectively adjust the compressor speed based on the difference between the PV generation and AC power. The dynamic performance of the adaptive control was investigated experimentally. The compressor operated at maximal speed when the PV generation was higher than AC maximal power. When the PV generation fluctuated, the compressor speed was adjusted accordingly. The simulation results presented that a proper configuration of PV and AC capacities could reach a fundamental energy match, while excess photovoltaic energy was supplied back to the grid, contributing to carbon neutrality. Carbon neutrality could be achieved by installing a large PV capacity. However, increasing the PV capacity could impact the performance of the PVAC system. The indoor temperature was lower with a larger PV capacity, and thus the COP of the AC was lower. The study proved the feasibility of the adaptive control strategy and the potential of carbon neutrality of PVAC systems.