English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In order to estimate the critical temperature ratio (CTR) of thermoacoustic engines experimentally, a constant oscillation control method which regulates the pressure amplitude to a reference (constant) value has been proposed: the control system has a non-negative state variable of the pressure amplitude; the control law is of a proportional-integral (PI) controller driven by the tracking error; the output of the PI controller is utilized as a time-varying gain in driving signal of a loudspeaker to absorb or inject a power in the acoustic tube. A condition on PI gains for the equilibrium point to be asymptotically stable has been derived, which was agreed with the stability condition in experiments. In this paper, we focus on the fact that the closed-loop system with the zero P-gain becomes a marginal stable system of which differential equation is in separation of variables, a Lyapunov function candidate is constructed by modifying the initial-condition dependent constant of the system. As a result, global asymptotic stability is shown on the basis of the Lyapunov stability criterion without linear approximation.

Stability Analysis of Constant Oscillation Control System of which Proportional-Integral Controller's Output is used as Time-Varying Gain