A New Hydro-Compressed Air Storage System Using Repetitive-Controlled Technique

Abstract

A new method for adiabatic compressed air energy storage system is presented, this clean energy solution incorporates compressed ambient air with hydraulic oil in to improve the overall system's efficiency. The approach is based on a new technique of small-scale Compressed Air Energy Storage (CAES) systems; it is implemented using a new design of a Repetitive Controlled Compressed Air Hydro Energy Storage (RC-CAHES) system. The energy is charged using hydraulic pump, which is more efficient than pneumatic compressor in energy conversion. This proposed technique is adequate for residential applications as it is designed for small energy storage systems, with energy of 12kWh and maximum discharging power of 4kW. In addition, the system is simulated using MATLAB/SIMULINK with a 36 cubic meters storage tank and 3000-6000 kPa operating storage pressure. Furthermore, the performance of RC-CAHES system is studied from energy conversion perspective during charging phase. The feasibility of such energy storage system is demonstrated, and it has been verified that all system parameters such as pressure, temperature, work, and enthalpy have similar final results using both analytic and simulation analyses. The main contribution of this paper is that a new storage technique is introduced, and the performance of this technique has been studied and mathematically analyzed from the perspective of energy conversion efficiency, in addition, the instantaneous and continuous performance of power conversion and thermodynamic parameters are studied. By comparing the performance of new CAHES technique with a typical CAES technique that has a similar input power and operational parameters, the results showed that CAHES technique has better performance than typical CAES technique.