A switched inertance hydraulic system uses a fast switching valve to control flow or pressure and is potentially very efficient as it does not rely on dissipation of power by throttling. This article studies its performance using an analytical method which efficiently describes the system in the time domain and frequency domain. A lumped parameter model and a distributed parameter model have been used for investigation using different parameters and conditions. The analytical models have been validated in experiments and the results on a prototype device show a very promising performance. The proposed analytical models are effective for understanding, analysing and optimizing the characteristics and performance of a switched inertance hydraulic system.
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