No abstract

Intermittency characteristic of renewable energy sources can be resolved using an energy storage technology. The function of the energy storage system is to store the excess energy that is produced from various renewable energy sources during the off‐peak hours and releases the same energy during the peak hours. The energy that is produced from the renewable energy sources can be stored in different forms such as Mechanical, Electrical, Electrochemical, Thermal, Chemical energy etc. Among all these forms of stored energy, a CAES technology under the Mechanical form of energy is the most cost effective for the bulk energy storage purpose. It involves a combined operation of various components such as Compressor/Expander, Gas turbine, combustion chambers, heat exchangers, generator unit, and underground compressed air storage. This article focuses to review the detail of various CAES systems such as D‐CAES, A‐CAES, I‐CAES etc. Additionally, it presents various technologies that are used to improve the energy efficiency and applicability of the CAES system. It is found that a maximum RTE of the C‐CAES, A‐CAES, and I‐CAES are 54%, 71%, and 80%, respectively. In addition, the RTE of the modified CAES systems such as LP‐CAES, PH‐CAES, and SC‐CAES are about 90%, 80%, and 60 to 80%, respectively.

No abstract

Abstract. The priority flow divider valve (PFDV) is used in power hydraulic system to split the supply flow in dual paths, i.e., primary path and secondary path. The flow ratio in each path is either predetermined or can be adjustable as per the loading conditions. The stated properties of the valve can be applied in a steering mechanism in automobile and a hydrostatic power transmission unit in a wind turbine. In a steering mechanism, it helps the system to perform two different functions against two different loads simultaneously, whereas, in a wind turbine, it can be used in hydrostatic power transmission unit to reduce the power fluctuation obtained from it. The hydrostatic power transmission system with PFDV (SMHPTSPFDV) used in a steering mechanism and the hydrostatic power transmission system with PFDV (WTHPTSPFDV) used in a wind turbine are modeled using the bond graph technique, and simulated in SYMBOLS Shakti software to analyze the steady and dynamic performance of the PFDV. The user-defined rectangular and sinusoidal variable pump speed has been used as inputs for system performance analysis. It is found that the PFDV may handle dual loads simultaneously, and it eliminates the use of multiple control valves to operate the same dual loads. Hence, it not only improves the system stability but also reduces the maintenance cost of the system. Moreover, the power and energy loss through the PFDV have been analyzed for both applications. It has been found that the power loss through the PFDV is higher when it is connected with SMHPTSPFDV. Also, the influences on the power and energy loss through PFDV are analyzed under various loading conditions.

No abstract