Highly efficient semi‐active oil damper with energy recovery system

This paper presents a novel semi‐active oil damper developed to overcome the limitations of existing oil dampers by introducing a unique energy recovery system. The proposed device is equipped with an auxiliary oil tank outside its main cylinder, and solenoid valves control the oil flow between the main cylinder and the tank. Conventional oil dampers convert all the vibration energy to heat. However, the proposed device recovers the vibration energy as the strain energy of oil in the tank and reuses it at an optimum timing to enhance damper stroke. The proposed damper is expressed as a four‐element model consisting of a Maxwell model and a Voigt model in series. First, we describe the basic configuration of the device, and show how the energy recovery system works in accordance with the control algorithm. Second, we show the results of dynamic loading tests conducted on a full‐scale specimen and the results of simulation analyses using the four‐element model. Finally, we demonstrate the results of seismic response analyses using a high‐rise building model, and discuss the control effect in comparison with the results of existing oil dampers. This paper presents a novel semi‐active oil damper developed to break through the limitations of existing oil dampers by introducing a unique energy recovery system. This proposed damper recovers the vibration energy in the tank as oil strain energy and reuses it at an optimum timing to enhance damper stroke.