A Less Conservative Stability Criterion on Amplidyne Electrical Systems via a Generalized Quadratic Function Negative-Definiteness Approach

When it comes to amplidyne electrical systems (AESs), signals are transmitted through the network transmission channels, inevitably generating time-varying delay. When assessing the stability of such AESs with respect to the Lyapunov-Krasovskii functional, the quadratic polynomial function is always generated that takes into account the time-varying delay. This paper presents an approach for segmenting delay intervals by proposing a method for tangent intersection. The method utilizes the cross point between every two tangent lines to produce negative-definiteness conditions for the generalized quadratic function. This reduces the conservatism of existing conditions without the need for unexplained adjustable parameters or additional decision variables. Additionally, a less conservative approach is used to derive the stability criterion for AESs with time-varying delay. Simulation results demonstrate the superiority of the proposed method.